Molecular cloning of the Coch gene of guinea pig inner ear and its expression analysis in cultured fibrocytes of the spiral ligament.

Science.gov (United States)

Li, Lishu; Ikezono, Tetsuo; Sekine, Kuwon; Shindo, Susumu; Matsumura, Tomohiro; Pawankar, Ruby; Ichimiya, Issei; Yagi, Toshiaki

2010-08-01

We have cloned guinea pig Coch cDNA and the sequence information will be useful for future molecular study combined with physiological experiments. Proper Coch gene expression appears to be dependent on the unique extracellular micro-environment of the inner ear in vivo. These results provide insight into the Coch gene expression and its regulation. To characterize the guinea pig Coch gene, we performed molecular cloning and expression analysis in the inner ear and cultured fibrocytes of the spiral ligament. The Coch cDNA was isolated using RACE. Cochlin isofoms were studied by Western blot using three different types of mammalian inner ear. The cochlear fibrocytes were cultured and characterized by immunostaining. Coch gene expression in the fibrocytes was investigated and the influence of cytokine stimulation was evaluated. The full-length 1991 bp Coch cDNA that encodes a 553 amino acid protein was isolated. The sequence had significant homology with other mammals, and the sizes of the Cochlin isoforms were identical. In the cultured fibrocytes, Coch mRNA was expressed in a very small amount and the isoform production was different, compared with the results in vivo. Cytokine stimulation did not alter the level of mRNA expression or isoform formation.

Fibrocytes: A Novel Stromal Cells to Regulate Resistance to Anti-Angiogenic Therapy and Cancer Progression.

Science.gov (United States)

Goto, Hisatsugu; Nishioka, Yasuhiko

2017-12-29

An adequate blood supply is essential for cancer cells to survive and grow; thus, the concept of inhibiting tumor angiogenesis has been applied to cancer therapy, and several drugs are already in clinical use. It has been shown that treatment with those anti-angiogenic drugs improved the response rate and prolonged the survival of patients with various types of cancer; however, it is also true that the effect was mostly limited. Currently, the disappointing clinical results are explained by the existence of intrinsic or acquired resistance to the therapy mediated by both tumor cells and stromal cells. This article reviews the mechanisms of resistance mediated by stromal cells such as endothelial cells, pericytes, fibroblasts and myeloid cells, with an emphasis on fibrocytes, which were recently identified as the cell type responsible for regulating acquired resistance to anti-angiogenic therapy. In addition, the other emerging role of fibrocytes as mediator-producing cells in tumor progression is discussed.

The pathway to muscle fibrosis depends on myostatin stimulating the differentiation of fibro/adipogenic progenitor cells in chronic kidney disease.

Science.gov (United States)

Dong, Jiangling; Dong, Yanjun; Chen, Zihong; Mitch, William E; Zhang, Liping

2017-01-01

Fibrosis in skeletal muscle develops after injury or in response to chronic kidney disease (CKD), but the origin of cells becoming fibrous tissue and the initiating and sustaining mechanisms causing muscle fibrosis are unclear. We identified muscle fibro/adipogenic progenitor cells (FAPs) that potentially differentiate into adipose tissues or fibrosis. We also demonstrated that CKD stimulates myostatin production in muscle. Therefore, we tested whether CKD induces myostatin, which stimulates fibrotic differentiation of FAPs leading to fibrosis in skeletal muscles. We isolated FAPs from mouse muscles and found that myostatin stimulates their proliferation and conversion into fibrocytes. In vivo, FAPs isolated from EGFP-transgenic mice (FAPs-EGFP) were transplanted into muscles of mice with CKD or into mouse muscles that were treated with myostatin. CKD or myostatin stimulated FAPs-EGFP proliferation in muscle and increased α-smooth muscle actin expression in FAP-EGFP cells. When myostatin was inhibited with a neutralizing peptibody (a chimeric peptide-Fc fusion protein), the FAP proliferation and muscle fibrosis induced by CKD were both suppressed. Knocking down Smad3 in cultured FAPs interrupted their conversion into fibrocytes, indicating that myostatin directly converts FAPs into fibrocytes. Thus, counteracting myostatin may be a strategy for preventing the development of fibrosis in skeletal muscles of patients with CKD. Copyright © 2016 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.

Differentiation state of skin fibroblast cultures versus risk of subcutaneous fibrosis after radiotherapy

International Nuclear Information System (INIS)

Herskind, C.; Bamberg, M.; Rodemann, H.P.; Bentzen, S.M.; Overgaard, J.; Overgaard, M.

1998-01-01

Background and purpose: There is increasing evidence for patient-to-patient variation in the response of normal tissue to radiotherapy. Recently, it has been suggested that accumulation of functional fibrocytes may be a key step in the development of radiation-induced fibrosis. Therefore, we have examined a possible relationship between the differentiation state of untreated fibroblasts and the risk of radiation-induced subcutaneous fibrosis in individual patients. Materials and methods: We used skin fibroblast cultures isolated from eight postmastectomy radiotherapy patients whose individual clinical radiosensitivity was assessed by the mean excess risk of fibrosis. Different types of potentially mitotic progenitor fibroblasts (MF) and postmitotic functional fibrocytes (PMF) in the terminal differentiation lineage (MFI approaches MFII approaches MFIII approaches PMF) were scored morphologically in clonal culture. Progression of differentiation was quantified by the ratio L/E of colony-forming late (MFIII and late MFII) and early (MFI and early MFII) progenitors. Results: We observed a correlation between the ratio L/E and the mean risk of fibrosis (r S =0.743, P=0.03), indicating an approximately 10-fold increase in L/E with an increasing risk of fibrosis. This was paralleled by a decreasing trend in the absolute numbers of early progenitor types. By contrast, there was no significant correlation between the plating efficiency and the risk of fibrosis. Conclusions: The data suggest that the risk of fibrosis increases with the progression of the differentiation of untreated progenitor fibroblasts, indicating that the progression of fibroblast differentiation may be a co-factor in the development of radiation-induced fibrosis. If this hypothesis is validated, it provides a rationale for a novel predictive test to identify patients with an increased risk of subcutaneous fibrosis. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

A UNIFYING DIFFERENTIAL GAME OF ADVERTISING AND PROMOTIONS

OpenAIRE

HASSAN BENCHEKROUN

2007-01-01

The literature on advertising and promotions can be divided in two categories. A first group of models assume that promotion contributes (positively) to the goodwill towards the product, and a second group assumes that promotions reduce that goodwill. In this paper we build a differential game model where the impact of promotion on goodwill is endogenously determined. We conduct a comparative dynamics exercise. An unexpected result is that an increase in the sensitivity of sales to goodwill c...

Effects of Internet Sales Promotion on a Differential Advertising Model

Directory of Open Access Journals (Sweden)

Hui Jiang

2018-01-01

Full Text Available Advertising and sales promotion are two important specific marketing communications tools. In this paper, Internet sales promotion is introduced into a differential advertising model and investigated quantitatively. The conditions for the existence and stability of periodic solutions are obtained. Flip bifurcation of periodic solution is investigated analytically. The results show that the sales promotion parameter can modify the stability of the differential advertising model and lead to chaos through flip bifurcation, the sales level will eventually be no less than a given value by adjusting the value of the sales promotion parameter, and the optimal sales promotion strategy can lead to maximum profit. Numerical results for periodic solutions, bifurcation diagrams, and the effects of sales promotion strategies, which are illustrated with an example, are in good agreement with the theoretical analysis. These results have certain significant theoretical and practical value in related markets.

Three-dimensional piezoelectric fibrous scaffolds selectively promote mesenchymal stem cell differentiation.

Science.gov (United States)

Damaraju, Sita M; Shen, Yueyang; Elele, Ezinwa; Khusid, Boris; Eshghinejad, Ahmad; Li, Jiangyu; Jaffe, Michael; Arinzeh, Treena Livingston

2017-12-01

The discovery of electric fields in biological tissues has led to efforts in developing technologies utilizing electrical stimulation for therapeutic applications. Native tissues, such as cartilage and bone, exhibit piezoelectric behavior, wherein electrical activity can be generated due to mechanical deformation. Yet, the use of piezoelectric materials have largely been unexplored as a potential strategy in tissue engineering, wherein a piezoelectric biomaterial acts as a scaffold to promote cell behavior and the formation of large tissues. Here we show, for the first time, that piezoelectric materials can be fabricated into flexible, three-dimensional fibrous scaffolds and can be used to stimulate human mesenchymal stem cell differentiation and corresponding extracellular matrix/tissue formation in physiological loading conditions. Piezoelectric scaffolds that exhibit low voltage output, or streaming potential, promoted chondrogenic differentiation and piezoelectric scaffolds with a high voltage output promoted osteogenic differentiation. Electromechanical stimulus promoted greater differentiation than mechanical loading alone. Results demonstrate the additive effect of electromechanical stimulus on stem cell differentiation, which is an important design consideration for tissue engineering scaffolds. Piezoelectric, smart materials are attractive as scaffolds for regenerative medicine strategies due to their inherent electrical properties without the need for external power sources for electrical stimulation. Copyright © 2017 Elsevier Ltd. All rights reserved.

Tridax procumbens flavonoids promote osteoblast differentiation and bone formation

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Md. Abdullah Al Mamun

Full Text Available BACKGROUND: Tridaxprocumbens flavonoids (TPFs are well known for their medicinal properties among local natives. Besides traditionally used for dropsy, anemia, arthritis, gout, asthma, ulcer, piles, and urinary problems, it is also used in treating gastric problems, body pain, and rheumatic pains of joints. TPFs have been reported to increase osteogenic functioning in mesenchymal stem cells. Our previous study showed that TPFs were significantly suppressed the RANKL-induced differentiation of osteoclasts and bone resorption. However, the effects of TPFs to promote osteoblasts differentiation and bone formation remain unclear. TPFs were isolated from Tridax procumbens and investigated for their effects on osteoblasts differentiation and bone formation by using primary mouse calvarial osteoblasts RESULTS: TPFs promoted osteoblast differentiation in a dose-dependent manner demonstrated by up-regulation of alkaline phosphatase and osteocalcin. TPFs also upregulated osteoblast differentiation related genes, including osteocalcin, osterix, and Runx2 in primary osteoblasts. TPFs treated primary osteoblast cells showed significant upregulation of bone morphogenetic proteins (BMPs including Bmp-2, Bmp-4, and Bmp-7. Addition of noggin, a BMP specific-antagonist, inhibited TPFs induced upregulation of the osteocalcin, osterix, and Runx2 CONCLUSION: Our findings point towards the induction of osteoblast differentiation by TPFs and suggested that TPFs could be a potential anabolic agent to treat patients with bone loss-associated diseases such as osteoporosis

Dynamic Rewiring of Promoter-Anchored Chromatin Loops during Adipocyte Differentiation

DEFF Research Database (Denmark)

Siersbæk, Rasmus; Madsen, Jesper Grud Skat; Javierre, Biola Maria

2017-01-01

-C to demonstrate a rapid reorganization of promoter-anchored chromatin loops within 4 hr after inducing differentiation of 3T3-L1 preadipocytes. The establishment of new promoter-enhancer loops is tightly coupled to activation of poised (histone H3 lysine 4 mono- and dimethylated) enhancers, as evidenced...

Carnosol promotes endothelial differentiation under H2O2-induced oxidative stress

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Ou Shulin

2017-01-01

Full Text Available Oxidative stress causes deregulation of endothelial cell differentiation. Carnosol is a potent antioxidant and antiinflammatory compound. In the present study, we examined whether the antioxidant effect of carnosol might protect bone marrow stem cells against H2O2-induced oxidative stress and promote endothelial differentiation. We examined cell viability by the MTT assay; oxidative stress and apoptosis were analyzed through changes in ROS levels, apoptotic ratio and caspase-3 activity; changes in protein expression of OCT-4, Flk-1, CD31 and Nrf-2 were assessed by Western blot analysis. H2O2 treatment increased oxidative stress and reduced cell viability, while the stem cell marker OCT-4 and endothelial markers Flk-1, CD31 were significantly downregulated as a result of the treatment with H2O2. Treatment with carnosol improved the antioxidant status, increased OCT-4 expression and promoted endothelial differentiation. This study provides evidence that carnosol could increase the antioxidant defense mechanism and promote endothelial differentiation.

Heparin-binding epidermal growth factor-like growth factor promotes neuroblastoma differentiation.

Science.gov (United States)

Gaviglio, Angela L; Knelson, Erik H; Blobe, Gerard C

2017-05-01

High-risk neuroblastoma is characterized by undifferentiated neuroblasts and low schwannian stroma content. The tumor stroma contributes to the suppression of tumor growth by releasing soluble factors that promote neuroblast differentiation. Here we identify heparin-binding epidermal growth factor-like growth factor (HBEGF) as a potent prodifferentiating factor in neuroblastoma. HBEGF mRNA expression is decreased in human neuroblastoma tumors compared with benign tumors, with loss correlating with decreased survival. HBEGF protein is expressed only in stromal compartments of human neuroblastoma specimens, with tissue from high-stage disease containing very little stroma or HBEGF expression. In 3 human neuroblastoma cell lines (SK-N-AS, SK-N-BE2, and SH-SY5Y), soluble HBEGF is sufficient to promote neuroblast differentiation and decrease proliferation. Heparan sulfate proteoglycans and heparin derivatives further enhance HBEGF-induced differentiation by forming a complex with the epidermal growth factor receptor, leading to activation of the ERK1/2 and STAT3 pathways and up-regulation of the inhibitor of DNA binding transcription factor. These data support a role for loss of HBEGF in the neuroblastoma tumor microenvironment in neuroblastoma pathogenesis.-Gaviglio, A. L., Knelson, E. H., Blobe, G. C. Heparin-binding epidermal growth factor-like growth factor promotes neuroblastoma differentiation. © FASEB.

Alteration of keratinocyte differentiation and senescence by the tumor promoter dioxin

International Nuclear Information System (INIS)

Ray, Soma S.; Swanson, Hollie I.

2003-01-01

Exposure to the environmental contaminant dioxin, elicits a variety of responses, which includes tumor promotion, embryotoxicity/teratogenesis, and carcinogenesis in both animals and humans. Many of the effects of dioxin are mediated by the aryl hydrocarbon receptor (AHR), a ligand-activated bHLH (basic helix-loop-helix)/PAS transcription factor. We initiated this study to determine whether dioxin's tumor-promoting activities may lie in its ability to alter proliferation, differentiation, and/or senescence using normal human epidermal keratinocytes (HEKs). Here, we report that dioxin appears to accelerate differentiation as measured by flow cytometry and by increased expression of the differentiation markers involucrin and filaggrin. In addition, dioxin appears to increase proliferation as indicated by an increase in NADH/NADPH production and changes in cell cycle. Finally, dioxin decreases SA (senescence associated) β-galactosidase staining, an indicator of senescence, in the differentiating keratinocytes. These changes were accompanied by decreases in the expression levels of key cell cycle regulatory proteins p53, p16 INK4a , and p14 ARF . Our findings support the idea that dioxin may exert its tumor-promoting actions, in part, by downregulating the expression levels of key tumor suppressor proteins, which may impair the cell's ability to maintain its appropriate cellular status

Secreted Frizzled related protein-4 (sFRP4) promotes epidermal differentiation and apoptosis

International Nuclear Information System (INIS)

Maganga, Richard; Giles, Natalie; Adcroft, Katharine; Unni, Ambili; Keeney, Diane; Wood, Fiona; Fear, Mark; Dharmarajan, Arunasalam

2008-01-01

The skin provides vital protection from infection and dehydration. Maintenance of the skin is through a constant program of proliferation, differentiation and apoptosis of epidermal cells, whereby proliferating cells in the basal layer differentiating to form the keratinized, anucleated stratum corneum. The WNT signalling pathway is known to be important in the skin. WNT signalling has been shown to be important both in epidermal development and in the maintenance and cycling of hair follicles and epidermal stem cells. However, the precise role for this pathway in epidermal differentiation remains unknown. We investigated the role of the WNT signalling inhibitor sFRP4 in epidermal differentiation. sFRP4 is expressed in both normal skin and keratinocytes in culture. Expression of sFRP4 mRNA and protein increases with keratinocyte differentiation and apoptosis, whilst exposure of keratinocytes to exogenous sFRP4 promotes apoptosis and expression of the terminal differentiation marker Involucrin. These data suggest sFRP4 promotes epidermal differentiation.

The canonical Wnt signaling pathway promotes chondrocyte differentiation in a Sox9-dependent manner

International Nuclear Information System (INIS)

Yano, Fumiko; Kugimiya, Fumitaka; Ohba, Shinsuke; Ikeda, Toshiyuki; Chikuda, Hirotaka; Ogasawara, Toru; Ogata, Naoshi; Takato, Tsuyoshi; Nakamura, Kozo; Kawaguchi, Hiroshi; Chung, Ung-il

2005-01-01

To better understand the role of the canonical Wnt signaling pathway in cartilage development, we adenovirally expressed a constitutively active (Canada) or a dominant negative (dn) form of lymphoid enhancer factor-1 (LEF-1), the main nuclear effector of the pathway, in undifferentiated mesenchymal cells, chondrogenic cells, and primary chondrocytes, and examined the expression of markers for chondrogenic differentiation and hypertrophy. caLEF-1 and LiCl, an activator of the canonical pathway, promoted both chondrogenic differentiation and hypertrophy, whereas dnLEF-1 and the gene silencing of β-catenin suppressed LiCl-promoted effects. To investigate whether these effects were dependent on Sox9, a master regulator of cartilage development, we stimulated Sox9-deficient ES cells with the pathway. caLEF-1 and LiCl promoted both chondrogenic differentiation and hypertrophy in wild-type, but not in Sox9-deficient, cells. The response of Sox9-deficient cells was restored by the adenoviral expression of Sox9. Thus, the canonical Wnt signaling pathway promotes chondrocyte differentiation in a Sox9-dependent manner

Indian hedgehog (Ihh) both promotes and restricts thymocyte differentiation.

Science.gov (United States)

Outram, Susan V; Hager-Theodorides, Ariadne L; Shah, Divya K; Rowbotham, Nicola J; Drakopoulou, Ekati; Ross, Susan E; Lanske, Beate; Dessens, Johannes T; Crompton, Tessa

2009-03-05

We show that Indian Hedgehog (Ihh) regulates T-cell development and homeostasis in both fetal and adult thymus, controlling thymocyte number. Fetal Ihh(-/-) thymi had reduced differentiation to double-positive (DP) cell and reduced cell numbers compared with wild-type littermates. Surprisingly, fetal Ihh(+/-) thymi had increased thymocyte numbers and proportion of DP cells relative to wild type, indicating that Ihh also negatively regulates thymocyte development. In vitro treatment of thymus explants with exogenous recombinant Hedgehog protein promoted thymocyte development in Ihh(-/-) thymi but inhibited thymocyte development in Ihh(+/-), confirming both positive and negative regulatory functions of Ihh. Analysis of Rag(-/-)Ihh(+/-) thymi showed that Ihh promotes T-cell development before pre-T-cell receptor (pre-TCR) signaling, but negatively regulates T-cell development only after pre-TCR signaling has taken place. We show that Ihh is most highly expressed by the DP population and that Ihh produced by DP cells feeds back to negatively regulate the differentiation and proliferation of their double-negative progenitors. Thus, differentiation from double-negative to DP cell, and hence the size of the DP population, is dependent on the concentration of Ihh in the thymus. Analysis of Ihh conditional knockout and heterozygote adult mice showed that Ihh also influences thymocyte number in the adult.

Vascular Mural Cells Promote Noradrenergic Differentiation of Embryonic Sympathetic Neurons

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Vitor Fortuna

2015-06-01

Full Text Available The sympathetic nervous system controls smooth muscle tone and heart rate in the cardiovascular system. Postganglionic sympathetic neurons (SNs develop in close proximity to the dorsal aorta (DA and innervate visceral smooth muscle targets. Here, we use the zebrafish embryo to ask whether the DA is required for SN development. We show that noradrenergic (NA differentiation of SN precursors temporally coincides with vascular mural cell (VMC recruitment to the DA and vascular maturation. Blocking vascular maturation inhibits VMC recruitment and blocks NA differentiation of SN precursors. Inhibition of platelet-derived growth factor receptor (PDGFR signaling prevents VMC differentiation and also blocks NA differentiation of SN precursors. NA differentiation is normal in cloche mutants that are devoid of endothelial cells but have VMCs. Thus, PDGFR-mediated mural cell recruitment mediates neurovascular interactions between the aorta and sympathetic precursors and promotes their noradrenergic differentiation.

Exogenous hydrogen sulfide promotes cell proliferation and differentiation by modulating autophagy in human keratinocytes

International Nuclear Information System (INIS)

Xie, Xin; Dai, Hui; Zhuang, Binyu; Chai, Li; Xie, Yanguang; Li, Yuzhen

2016-01-01

The effects and the underlying mechanisms of hydrogen sulfide (H 2 S) on keratinocyte proliferation and differentiation are still less known. In the current study, we investigated the effects and the underlying mechanisms of exogenous H 2 S on keratinocyte proliferation and differentiation. Human keratinocytes (HaCaT cells) were treated with various concentrations (0.05, 0.25, 0.5 and 1 mM) of sodium hydrosulfide (NaHS, a donor of H 2 S) for 24 h. A CCK-8 assay was used to assess cell viability. Western blot analysis was performed to determine the expression levels of proteins associated with differentiation and autophagy. Transmission electron microscopy was performed to observe autophagic vacuoles, and flow cytometry was applied to evaluate apoptosis. NaHS promoted the viability, induced the differentiation, and enhanced autophagic activity in a dose-dependent manner in HaCaT cells but had no effect on cell apoptosis. Blockage of autophagy by ATG5 siRNA inhibited NaHS-induced cell proliferation and differentiation. The current study demonstrated that autophagy in response to exogenous H 2 S treatment promoted keratinocyte proliferation and differentiation. Our results provide additional insights into the potential role of autophagy in keratinocyte proliferation and differentiation. - Highlights: • Exogenous H 2 S promotes keratinocyte proliferation and differentiation. • The effects of H 2 S on proliferation and differentiation is modulated by autophagy. • Exogenous H 2 S has no effect on keratinocyte apoptosis.

Interleukin-33 promoting Th1 lymphocyte differentiation dependents on IL-12.

Science.gov (United States)

Komai-Koma, Mousa; Wang, Eryi; Kurowska-Stolarska, Mariola; Li, Dong; McSharry, Charles; Xu, Damo

2016-03-01

The pro-Th2 cytokine IL-33 is now emerging as an important Th1 cytokine-IFN-γ inducer in murine CD4(+) T cells that is essential for protective cell-mediated immunity against viral infection in mice. However, whether IL-33 can promote human Th1 cell differentiation and how IL-33 polarizes Th1 cells is less understood. We assessed the ability of IL-33 to induce Th1 cell differentiation and IFN-γ production in vitro and in vivo. We report here that IL-33 alone had no ability in Th1 cell polarization. However it potentiated IL-12-mediated Th1 cell differentiation and IFN-γ production in TCR-stimulated murine and human CD4(+) T cells in vitro and in vivo. IL-33 promoted Th1 cell development via MyD88 and synergized with IL-12 to enhance St2 and IL-12R expression in CD4(+) T cells. These data therefore provide a novel mechanism for Th1 cell differentiation and optimal induction of a Type 1 response. Thus, IL-33 is capable of inducing IL-12-dependent Th1 cell differentiation in human and mouse CD4(+) T cells. Copyright © 2015 The Authors. Published by Elsevier GmbH.. All rights reserved.

Vascular Mural Cells Promote Noradrenergic Differentiation of Embryonic Sympathetic Neurons.

Science.gov (United States)

Fortuna, Vitor; Pardanaud, Luc; Brunet, Isabelle; Ola, Roxana; Ristori, Emma; Santoro, Massimo M; Nicoli, Stefania; Eichmann, Anne

2015-06-23

The sympathetic nervous system controls smooth muscle tone and heart rate in the cardiovascular system. Postganglionic sympathetic neurons (SNs) develop in close proximity to the dorsal aorta (DA) and innervate visceral smooth muscle targets. Here, we use the zebrafish embryo to ask whether the DA is required for SN development. We show that noradrenergic (NA) differentiation of SN precursors temporally coincides with vascular mural cell (VMC) recruitment to the DA and vascular maturation. Blocking vascular maturation inhibits VMC recruitment and blocks NA differentiation of SN precursors. Inhibition of platelet-derived growth factor receptor (PDGFR) signaling prevents VMC differentiation and also blocks NA differentiation of SN precursors. NA differentiation is normal in cloche mutants that are devoid of endothelial cells but have VMCs. Thus, PDGFR-mediated mural cell recruitment mediates neurovascular interactions between the aorta and sympathetic precursors and promotes their noradrenergic differentiation. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

Exogenous hydrogen sulfide promotes cell proliferation and differentiation by modulating autophagy in human keratinocytes

Energy Technology Data Exchange (ETDEWEB)

Xie, Xin [Department of Dermatology, The Second Affiliated Hospital of Harbin Medical University, Harbin, 150086, Heilongjiang Province (China); Dai, Hui [Department of Cardiology, The First Affiliated Hospital of Harbin Medical University, Harbin, 150001, Heilongjiang Province (China); Zhuang, Binyu [Department of Dermatology, The Second Affiliated Hospital of Harbin Medical University, Harbin, 150086, Heilongjiang Province (China); Chai, Li; Xie, Yanguang [Institute of Dermatology of Heilongjiang Province, Harbin, 150001, Heilongjiang Province (China); Li, Yuzhen, E-mail: liyuzhen@medmail.com.cn [Department of Dermatology, The Second Affiliated Hospital of Harbin Medical University, Harbin, 150086, Heilongjiang Province (China)

2016-04-08

The effects and the underlying mechanisms of hydrogen sulfide (H{sub 2}S) on keratinocyte proliferation and differentiation are still less known. In the current study, we investigated the effects and the underlying mechanisms of exogenous H{sub 2}S on keratinocyte proliferation and differentiation. Human keratinocytes (HaCaT cells) were treated with various concentrations (0.05, 0.25, 0.5 and 1 mM) of sodium hydrosulfide (NaHS, a donor of H{sub 2}S) for 24 h. A CCK-8 assay was used to assess cell viability. Western blot analysis was performed to determine the expression levels of proteins associated with differentiation and autophagy. Transmission electron microscopy was performed to observe autophagic vacuoles, and flow cytometry was applied to evaluate apoptosis. NaHS promoted the viability, induced the differentiation, and enhanced autophagic activity in a dose-dependent manner in HaCaT cells but had no effect on cell apoptosis. Blockage of autophagy by ATG5 siRNA inhibited NaHS-induced cell proliferation and differentiation. The current study demonstrated that autophagy in response to exogenous H{sub 2}S treatment promoted keratinocyte proliferation and differentiation. Our results provide additional insights into the potential role of autophagy in keratinocyte proliferation and differentiation. - Highlights: • Exogenous H{sub 2}S promotes keratinocyte proliferation and differentiation. • The effects of H{sub 2}S on proliferation and differentiation is modulated by autophagy. • Exogenous H{sub 2}S has no effect on keratinocyte apoptosis.

Induction of NFATc2 expression by interleukin 6 promotes T helper type 2 differentiation.

Science.gov (United States)

Diehl, Sean; Chow, Chi-Wing; Weiss, Linda; Palmetshofer, Alois; Twardzik, Thomas; Rounds, Laura; Serfling, Edgar; Davis, Roger J; Anguita, Juan; Rincón, Mercedes

2002-07-01

Interleukin (IL)-6 is produced by professional antigen-presenting cells (APCs) such as B cells, macrophages, and dendritic cells. It has been previously shown that APC-derived IL-6 promotes the differentiation of naive CD4+ T cells into effector T helper type 2 (Th2) cells. Here, we have studied the molecular mechanism for IL-6-mediated Th2 differentiation. During the activation of CD4+ T cells, IL-6 induces the production of IL-4, which promotes the differentiation of these cells into effector Th2 cells. Regulation of IL-4 gene expression by IL-6 is mediated by nuclear factor of activated T cells (NFAT), as inhibition of NFAT prevents IL-6-driven IL-4 production and Th2 differentiation. IL-6 upregulates NFAT transcriptional activity by increasing the levels of NFATc2. The ability of IL-6 to promote Th2 differentiation is impaired in CD4+ T cells that lack NFATc2, demonstrating that NFATc2 is required for regulation of IL-4 gene expression by IL-6. Regulation of NFATc2 expression and NFAT transcriptional activity represents a novel pathway by which IL-6 can modulate gene expression.

Methylation of miR-145a-5p promoter mediates adipocytes differentiation

Energy Technology Data Exchange (ETDEWEB)

Du, Jingjing; Cheng, Xiao; Shen, Linyuan; Tan, Zhendong; Luo, Jia; Wu, Xiaoqian; Liu, Chendong [College of Animal Science and Technology, Sichuan Agricultural University, Chengdu 611130 (China); Yang, Qiong [Department of Animal Husbandry and Veterinary Medicine, Chengdu Agricultural College, Chengdu 611100, Sichuan (China); Jiang, Yanzhi [College of Life and Science, Sichuan Agricultural University, Chengdu 611130 (China); Tang, Guoqing; Li, Xuewei [College of Animal Science and Technology, Sichuan Agricultural University, Chengdu 611130 (China); Zhang, Shunhua, E-mail: zhangsh1919@163.com [College of Animal Science and Technology, Sichuan Agricultural University, Chengdu 611130 (China); Zhu, Li, E-mail: zhuli7508@163.com [College of Animal Science and Technology, Sichuan Agricultural University, Chengdu 611130 (China)

2016-06-17

MicroRNAs (miRNAs, miR) play important roles in adipocyte development. Recent studies showed that the expression of several miRNAs is closely related with promoter methylation. However, it is not known whether miRNA mediates adipocytes differentiation by means of DNA methylation. Here, we showed that miR-145a-5p was poorly expressed in adipose tissue from mice fed a high fat diet (HFD). Overexpression or inhibition of miR-145a-5p was unfavorable or beneficial, respectively, for adipogenesis, and these effects were achieved by regulating adipocyte-specific genes involved in lipogenic transcription, fatty acid synthesis, and fatty acid transportation. Particularly, we first suggested that miR-145a-5p mimics or inhibitors promoted or repressed adipocytes proliferation by regulating p53 and p21, which act as cell cycle regulating factors. Surprisingly, the miR-145a-5p-repressed adipocyte differentiation was enhanced or rescued when cells treated with 5-Aza-dC were transfected with miR-145a-5p mimics or inhibitors, respectively. These data indicated that, as a new mean to positively regulate adipocyte proliferation, the process of miR-145a-5p-inhibited adipogenesis may be regulated by DNA methylation. -- Highlights: •MiR-145a-5p promotes adipocytes proliferation. •MiR-145a-5p is negatively correlated with obesity. •MiR-145a-5p mediates adipocytes differentiation via regulating pathway related adipocytes differentiation. MiR-145a-5p mediating adipocytes differentiation was regulated by DNA methylation.

Arctigenin protects against neuronal hearing loss by promoting neural stem cell survival and differentiation.

Science.gov (United States)

Huang, Xinghua; Chen, Mo; Ding, Yan; Wang, Qin

2017-03-01

Neuronal hearing loss has become a prevalent health problem. This study focused on the function of arctigenin (ARC) in promoting survival and neuronal differentiation of mouse cochlear neural stem cells (NSCs), and its protection against gentamicin (GMC) induced neuronal hearing loss. Mouse cochlea was used to isolate NSCs, which were subsequently cultured in vitro. The effects of ARC on NSC survival, neurosphere formation, differentiation of NSCs, neurite outgrowth, and neural excitability in neuronal network in vitro were examined. Mechanotransduction ability demonstrated by intact cochlea, auditory brainstem response (ABR), and distortion product optoacoustic emissions (DPOAE) amplitude in mice were measured to evaluate effects of ARC on GMC-induced neuronal hearing loss. ARC increased survival, neurosphere formation, neuron differentiation of NSCs in mouse cochlear in vitro. ARC also promoted the outgrowth of neurites, as well as neural excitability of the NSC-differentiated neuron culture. Additionally, ARC rescued mechanotransduction capacity, restored the threshold shifts of ABR and DPOAE in our GMC ototoxicity murine model. This study supports the potential therapeutic role of ARC in promoting both NSCs proliferation and differentiation in vitro to functional neurons, thus supporting its protective function in the therapeutic treatment of neuropathic hearing loss in vivo. © 2017 Wiley Periodicals, Inc.

Alternans promotion in cardiac electrophysiology models by delay differential equations.

Science.gov (United States)

Gomes, Johnny M; Dos Santos, Rodrigo Weber; Cherry, Elizabeth M

2017-09-01

Cardiac electrical alternans is a state of alternation between long and short action potentials and is frequently associated with harmful cardiac conditions. Different dynamic mechanisms can give rise to alternans; however, many cardiac models based on ordinary differential equations are not able to reproduce this phenomenon. A previous study showed that alternans can be induced by the introduction of delay differential equations (DDEs) in the formulations of the ion channel gating variables of a canine myocyte model. The present work demonstrates that this technique is not model-specific by successfully promoting alternans using DDEs for five cardiac electrophysiology models that describe different types of myocytes, with varying degrees of complexity. By analyzing results across the different models, we observe two potential requirements for alternans promotion via DDEs for ionic gates: (i) the gate must have a significant influence on the action potential duration and (ii) a delay must significantly impair the gate's recovery between consecutive action potentials.

Alternans promotion in cardiac electrophysiology models by delay differential equations

Science.gov (United States)

Gomes, Johnny M.; dos Santos, Rodrigo Weber; Cherry, Elizabeth M.

2017-09-01

Cardiac electrical alternans is a state of alternation between long and short action potentials and is frequently associated with harmful cardiac conditions. Different dynamic mechanisms can give rise to alternans; however, many cardiac models based on ordinary differential equations are not able to reproduce this phenomenon. A previous study showed that alternans can be induced by the introduction of delay differential equations (DDEs) in the formulations of the ion channel gating variables of a canine myocyte model. The present work demonstrates that this technique is not model-specific by successfully promoting alternans using DDEs for five cardiac electrophysiology models that describe different types of myocytes, with varying degrees of complexity. By analyzing results across the different models, we observe two potential requirements for alternans promotion via DDEs for ionic gates: (i) the gate must have a significant influence on the action potential duration and (ii) a delay must significantly impair the gate's recovery between consecutive action potentials.

Osteogenic differentiation of mouse mesenchymal progenitor cell, Kusa-A1 is promoted by mammalian transcriptional repressor Rbpj

International Nuclear Information System (INIS)

Wang, Shengchao; Kawashima, Nobuyuki; Sakamoto, Kei; Katsube, Ken-ichi; Umezawa, Akihiro; Suda, Hideaki

2010-01-01

Research highlights: → High Rbpj mRNA expression was observed in mesenchymal cells surrounding the bone of mouse embryos. → Overexpression of Rbpj depressed Notch-Hes1/Hey1 signaling. → Rbpj upregulated promoter activities of Runx2 and Ose2. → Rbpj promoted osteoblastic differentiation/maturation in Kusa-A1 cells. -- Abstract: Pluripotent mesenchymal stem cells possess the ability to differentiate into many cell types, but the precise mechanisms of differentiation are still unclear. Here, we provide evidence that Rbpj (recombination signal-binding protein for immunoglobulin kappa j region) protein, the primary nuclear mediator of Notch, is involved in osteogenesis. Overexpression of Rbpj promoted osteogenic differentiation of mouse Kusa-A1 cells in vitro and in vivo. Transient transfection of an Rbpj expression vector into Kusa-A1 cells upregulated promoter activities of Runx2 and Ose2. Enhanced osteogenic potentials including high alkaline phosphatase activity, rapid calcium deposition, and increased calcified nodule formation, were observed in established stable Rbpj-overexpressing Kusa-A1 (Kusa-A1/Rbpj) cell line. In vivo mineralization by Kusa-A1/Rbpj was promoted compared to that by Kusa-A1 host cells. Histological findings revealed that expression of Rbpj was primarily observed in osteoblasts. These results suggest that Rbpj may play essential roles in osteoblast differentiation.

Osteogenic differentiation of mouse mesenchymal progenitor cell, Kusa-A1 is promoted by mammalian transcriptional repressor Rbpj

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Wang, Shengchao [Department of Preventive Dentistry, School of Stomatology, The Fourth Military Medical University, 145 West Changle Road, 710032 Xi' an (China); Kawashima, Nobuyuki, E-mail: kawashima.n.endo@tmd.ac.jp [Department of Pulp Biology and Endodontics, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8549 (Japan); Sakamoto, Kei; Katsube, Ken-ichi [Department of Oral Pathology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8549 (Japan); Umezawa, Akihiro [Department of Reproductive Biology and Pathology, National Institute for Child Health and Development, 2-10-4 Ohkura, Setagaya-ku, Tokyo 157-8535 (Japan); Suda, Hideaki [Department of Pulp Biology and Endodontics, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8549 (Japan); GCOE Program, International Research Center for Molecular Science in Tooth and Bone Diseases, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8549 (Japan)

2010-09-10

Research highlights: {yields} High Rbpj mRNA expression was observed in mesenchymal cells surrounding the bone of mouse embryos. {yields} Overexpression of Rbpj depressed Notch-Hes1/Hey1 signaling. {yields} Rbpj upregulated promoter activities of Runx2 and Ose2. {yields} Rbpj promoted osteoblastic differentiation/maturation in Kusa-A1 cells. -- Abstract: Pluripotent mesenchymal stem cells possess the ability to differentiate into many cell types, but the precise mechanisms of differentiation are still unclear. Here, we provide evidence that Rbpj (recombination signal-binding protein for immunoglobulin kappa j region) protein, the primary nuclear mediator of Notch, is involved in osteogenesis. Overexpression of Rbpj promoted osteogenic differentiation of mouse Kusa-A1 cells in vitro and in vivo. Transient transfection of an Rbpj expression vector into Kusa-A1 cells upregulated promoter activities of Runx2 and Ose2. Enhanced osteogenic potentials including high alkaline phosphatase activity, rapid calcium deposition, and increased calcified nodule formation, were observed in established stable Rbpj-overexpressing Kusa-A1 (Kusa-A1/Rbpj) cell line. In vivo mineralization by Kusa-A1/Rbpj was promoted compared to that by Kusa-A1 host cells. Histological findings revealed that expression of Rbpj was primarily observed in osteoblasts. These results suggest that Rbpj may play essential roles in osteoblast differentiation.

Novel hydrated graphene ribbon unexpectedly promotes aged seed germination and root differentiation

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Hu, Xiangang; Zhou, Qixing

2014-01-01

It is well known that graphene (G) induces nanotoxicity towards living organisms. Here, a novel and biocompatible hydrated graphene ribbon (HGR) unexpectedly promoted aged (two years) seed germination. HGR formed at the normal temperature and pressure (120 days hydration), presented 17.1% oxygen, 0.9% nitrogen groups, disorder-layer structure, with 0.38 nm thickness ribbon morphology. Interestingly, there were bulges around the edges of HGR. Compared to G and graphene oxide (GO), HGR increased seed germination by 15% root differentiation between 52 and 59% and enhanced resistance to oxidative stress. The metabonomics analysis discovered that HGR upregulated carbohydrate, amino acid, and fatty acids metabolism that determined secondary metabolism, nitrogen sequestration, cell membrane integrity, permeability, and oxidation resistance. Hexadecanoic acid as a biomarker promoted root differentiation and increased the germination rate. Our discovery is a novel HGR that promotes aged seed germination, illustrates metabolic specificity among graphene-based materials, and inspires innovative concepts in the regulation of seed development.

Surface topography of hydroxyapatite promotes osteogenic differentiation of human bone marrow mesenchymal stem cells.

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Yang, Wanlei; Han, Weiqi; He, Wei; Li, Jianlei; Wang, Jirong; Feng, Haotian; Qian, Yu

2016-03-01

Effective and safe induction of osteogenic differentiation is one of the key elements of bone tissue engineering. Surface topography of scaffold materials was recently found to promote osteogenic differentiation. Utilization of this topography may be a safer approach than traditional induction by growth factors or chemicals. The aim of this study is to investigate the enhancement of osteogenic differentiation by surface topography and its mechanism of action. Hydroxyapatite (HA) discs with average roughness (Ra) of surface topography ranging from 0.2 to 1.65 μm and mean distance between peaks (RSm) ranging from 89.7 to 18.6 μm were prepared, and human bone-marrow mesenchymal stem cells (hBMSCs) were cultured on these discs. Optimal osteogenic differentiation was observed on discs with surface topography characterized by Ra ranging from 0.77 to 1.09 μm and RSm ranging from 53.9 to 39.3 μm. On this surface configuration of HA, hBMSCs showed oriented attachment, F-actin arrangement, and a peak in the expression of Yes-associated protein (YAP) and PDZ binding motif (TAZ) (YAP/TAZ). These results indicated that the surface topography of HA promoted osteogenic differentiation of hBMSCs, possibly by increasing cell attachment and promoting the YAP/TAZ signaling pathway. Copyright © 2015 Elsevier B.V. All rights reserved.

Combinatorial polymer electrospun matrices promote physiologically-relevant cardiomyogenic stem cell differentiation.

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Mukesh K Gupta

Full Text Available Myocardial infarction results in extensive cardiomyocyte death which can lead to fatal arrhythmias or congestive heart failure. Delivery of stem cells to repopulate damaged cardiac tissue may be an attractive and innovative solution for repairing the damaged heart. Instructive polymer scaffolds with a wide range of properties have been used extensively to direct the differentiation of stem cells. In this study, we have optimized the chemical and mechanical properties of an electrospun polymer mesh for directed differentiation of embryonic stem cells (ESCs towards a cardiomyogenic lineage. A combinatorial polymer library was prepared by copolymerizing three distinct subunits at varying molar ratios to tune the physicochemical properties of the resulting polymer: hydrophilic polyethylene glycol (PEG, hydrophobic poly(ε-caprolactone (PCL, and negatively-charged, carboxylated PCL (CPCL. Murine ESCs were cultured on electrospun polymeric scaffolds and their differentiation to cardiomyocytes was assessed through measurements of viability, intracellular reactive oxygen species (ROS, α-myosin heavy chain expression (α-MHC, and intracellular Ca(2+ signaling dynamics. Interestingly, ESCs on the most compliant substrate, 4%PEG-86%PCL-10%CPCL, exhibited the highest α-MHC expression as well as the most mature Ca(2+ signaling dynamics. To investigate the role of scaffold modulus in ESC differentiation, the scaffold fiber density was reduced by altering the electrospinning parameters. The reduced modulus was found to enhance α-MHC gene expression, and promote maturation of myocyte Ca(2+ handling. These data indicate that ESC-derived cardiomyocyte differentiation and maturation can be promoted by tuning the mechanical and chemical properties of polymer scaffold via copolymerization and electrospinning techniques.

Mussel-inspired alginate gel promoting the osteogenic differentiation of mesenchymal stem cells and anti-infection

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Zhang, Shiwen [Department of Mechanical Engineering, Faculty of Engineering and Department of Biochemistry & Genetics, Faculty of Medicine and Manitoba Institute of Child Health, The University of Manitoba, Winnipeg, Manitoba (Canada); Children Hospital Research Institute of Manitoba, Winnipeg (Canada); Sichuan University, Chengdu (China); Xu, Kaige; Darabi, Mohammad Ali [Children Hospital Research Institute of Manitoba, Winnipeg (Canada); Yuan, Quan [Sichuan University, Chengdu (China); Xing, Malcolm [Department of Mechanical Engineering, Faculty of Engineering and Department of Biochemistry & Genetics, Faculty of Medicine and Manitoba Institute of Child Health, The University of Manitoba, Winnipeg, Manitoba (Canada)

2016-12-01

Alginate hydrogels have been used in cell encapsulation for many years but a prevalent issue with pure alginates is that they are unable to provide enough bioactive properties to interact with mammalian cells. This paper discusses the modification of alginate with mussel-inspired dopamine for cell loading and anti-infection. Mouse bone marrow stem cells were immobilized into alginate and alginate-dopamine beads and fibers. Through live-dead and MTT assay, alginates modified by dopamine promoted cell viability and proliferation. In vitro cell differentiation results showed that such an alginate-dopamine gel can promote the osteogenic differentiation of mesenchymal stem cell after PCR and ALP assays. In addition to that, the adhesive prosperities of dopamine allowed for coating the surface of alginate-dopamine gel with silver nanoparticles, which provided the gel with significant antibacterial characteristics. Overall, these results demonstrate that a dopamine-modified alginate gel can be a great tool for cell encapsulation to promote cell proliferation and can be applied to bone regeneration, especially in contaminated bone defects. - Highlights: • Dopamine modified alginate bead and fiber promote cell viability and proliferation. • Alginate-dopamine gel promotes osteogenic differentiation of MSCs. • Dopamine reduced nanosilver for anti-infection. • Alginate-dopamine bead and fiber for delivery of mesenchymal stem cells (MSCs)

Mussel-inspired alginate gel promoting the osteogenic differentiation of mesenchymal stem cells and anti-infection

International Nuclear Information System (INIS)

Zhang, Shiwen; Xu, Kaige; Darabi, Mohammad Ali; Yuan, Quan; Xing, Malcolm

2016-01-01

Alginate hydrogels have been used in cell encapsulation for many years but a prevalent issue with pure alginates is that they are unable to provide enough bioactive properties to interact with mammalian cells. This paper discusses the modification of alginate with mussel-inspired dopamine for cell loading and anti-infection. Mouse bone marrow stem cells were immobilized into alginate and alginate-dopamine beads and fibers. Through live-dead and MTT assay, alginates modified by dopamine promoted cell viability and proliferation. In vitro cell differentiation results showed that such an alginate-dopamine gel can promote the osteogenic differentiation of mesenchymal stem cell after PCR and ALP assays. In addition to that, the adhesive prosperities of dopamine allowed for coating the surface of alginate-dopamine gel with silver nanoparticles, which provided the gel with significant antibacterial characteristics. Overall, these results demonstrate that a dopamine-modified alginate gel can be a great tool for cell encapsulation to promote cell proliferation and can be applied to bone regeneration, especially in contaminated bone defects. - Highlights: • Dopamine modified alginate bead and fiber promote cell viability and proliferation. • Alginate-dopamine gel promotes osteogenic differentiation of MSCs. • Dopamine reduced nanosilver for anti-infection. • Alginate-dopamine bead and fiber for delivery of mesenchymal stem cells (MSCs)

Zinc Promotes Adipose-Derived Mesenchymal Stem Cell Proliferation and Differentiation towards a Neuronal Fate.

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Moon, Mi-Young; Kim, Hyun Jung; Choi, Bo Young; Sohn, Min; Chung, Tae Nyoung; Suh, Sang Won

2018-01-01

Zinc is an essential element required for cell division, migration, and proliferation. Under zinc-deficient conditions, proliferation and differentiation of neural progenitors are significantly impaired. Adipose-derived mesenchymal stem cells (AD-MSCs) are multipotent stem cells that can differentiate into neurons. The aim of this study was to evaluate the effect of zinc on AD-MSC proliferation and differentiation. We initially examined the effect of zinc on stem cell proliferation at the undifferentiated stage. AD-MSCs showed high proliferation rates on day 6 in 30  μ M and 100  μ M of ZnCl 2 . Zinc chelation inhibited AD-MSC proliferation via downregulation of ERK1/2 activity. We then assessed whether zinc was involved in cell migration and neurite outgrowth during differentiation. After three days of neuronal differentiation, TUJ-1-positive cells were observed, implying that AD-MSCs had differentiated into early neuron or neuron-like cells. Neurite outgrowth was increased in the zinc-treated group, while the CaEDTA-treated group showed diminished, shrunken neurites. Furthermore, we showed that zinc promoted neurite outgrowth via the inactivation of RhoA and led to the induction of neuronal gene expression (MAP2 and nestin) in differentiated stem cells. Taken together, zinc promoted AD-MSC proliferation and affected neuronal differentiation, mainly by increasing neurite outgrowth.

Zinc Promotes Adipose-Derived Mesenchymal Stem Cell Proliferation and Differentiation towards a Neuronal Fate

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Mi-Young Moon

2018-01-01

Full Text Available Zinc is an essential element required for cell division, migration, and proliferation. Under zinc-deficient conditions, proliferation and differentiation of neural progenitors are significantly impaired. Adipose-derived mesenchymal stem cells (AD-MSCs are multipotent stem cells that can differentiate into neurons. The aim of this study was to evaluate the effect of zinc on AD-MSC proliferation and differentiation. We initially examined the effect of zinc on stem cell proliferation at the undifferentiated stage. AD-MSCs showed high proliferation rates on day 6 in 30 μM and 100 μM of ZnCl2. Zinc chelation inhibited AD-MSC proliferation via downregulation of ERK1/2 activity. We then assessed whether zinc was involved in cell migration and neurite outgrowth during differentiation. After three days of neuronal differentiation, TUJ-1-positive cells were observed, implying that AD-MSCs had differentiated into early neuron or neuron-like cells. Neurite outgrowth was increased in the zinc-treated group, while the CaEDTA-treated group showed diminished, shrunken neurites. Furthermore, we showed that zinc promoted neurite outgrowth via the inactivation of RhoA and led to the induction of neuronal gene expression (MAP2 and nestin in differentiated stem cells. Taken together, zinc promoted AD-MSC proliferation and affected neuronal differentiation, mainly by increasing neurite outgrowth.

Differentiation-promoting activity of pomegranate (Punica granatum) fruit extracts in HL-60 human promyelocytic leukemia cells.

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Kawaii, Satoru; Lansky, Ephraim P

2004-01-01

Differentiation refers to the ability of cancer cells to revert to their normal counterparts, and its induction represents an important noncytotoxic therapy for leukemia, and also breast, prostate, and other solid malignancies. Flavonoids are a group of differentiation-inducing chemicals with a potentially lower toxicology profile than retinoids. Flavonoid-rich polyphenol fractions from the pomegranate (Punica granatum) fruit exert anti-proliferative, anti-invasive, anti-eicosanoid, and pro-apoptotic actions in breast and prostate cancer cells and anti-angiogenic activities in vitro and in vivo. Here we tested flavonoid-rich fractions from fresh (J) and fermented (W) pomegranate juice and from an aqueous extraction of pomegranate pericarps (P) as potential differentiation-promoting agents of human HL-60 promyelocytic leukemia cells. Four assays were used to assess differentiation: nitro blue tetrazolium reducing activity, nonspecific esterase activity, specific esterase activity, and phagocytic activity. In addition, the effect of these extracts on HL-60 proliferation was evaluated. Extracts W and P were strong promoters of differentiation in all settings, with extract J showing only a relatively mild differentiation-promoting effect. The extracts had proportional inhibitory effects on HL-60 cell proliferation. The results highlight an important, previously unknown, mechanism of the cancer preventive and suppressive potential of pomegranate fermented juice and pericarp extracts.

Wnt-10b secreted from lymphocytes promotes differentiation of skin epithelial cells

International Nuclear Information System (INIS)

Ouji, Yukiteru; Yoshikawa, Masahide; Shiroi, Akira; Ishizaka, Shigeaki

2006-01-01

Wnt-10b was originally isolated from lymphoid tissue and is known to be involved in a wide range of biological actions, while recently it was found to be expressed early in the development of hair follicles. However, few studies have been conducted concerning the role of Wnt-10b with the differentiation of skin epithelial cells. To evaluate its role in epithelial differentiation, we purified Wnt-10b from the supernatant of a concanavalin A-stimulated lymphocyte culture using an affinity column and investigated its effects on the differentiation of adult mouse-derived primary skin epithelial cells (MPSEC). MPSEC cultured with Wnt-10b showed morphological changes from cuboidal to spindle-shaped with inhibited proliferation, and also obtained characteristics of the hair shaft and inner root sheath of the hair follicle, represented by red-colored Ayoub Shklar staining, and reactions to AE-13 and AE-15 as seen with immunocytology. Further, RT-PCR analysis demonstrated the expression of mRNA for keratin 1, keratin 2, loricrin, mHa5, and mHb5, in association with a decreased expression of the basal cell marker keratin 5, in Wnt-10b-treated MPSEC. In addition, involvement of the canonical Wnt signal pathway was demonstrated by a TCF reporter (pTOPFLASH) assay. These results suggest that Wnt-10b promotes the differentiation of MPSEC and may play an important role in hair follicle development by promoting differentiation of epithelial cells

[Phenotype-based primary screening for drugs promoting neuronal subtype differentiation in embryonic stem cells with light microscope].

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Gao, Yi-ning; Wang, Dan-ying; Pan, Zong-fu; Mei, Yu-qin; Wang, Zhi-qiang; Zhu, Dan-yan; Lou, Yi-jia

2012-07-01

To set up a platform for phenotype-based primary screening of drug candidates promoting neuronal subtype differentiation in embryonic stem cells (ES) with light microscope. Hanging drop culture 4-/4+ method was employed to harvest the cells around embryoid body (EB) at differentiation endpoint. Morphological evaluation for neuron-like cells was performed with light microscope. Axons for more than three times of the length of the cell body were considered as neuron-like cells. The compound(s) that promote neuron-like cells was further evaluated. Icariin (ICA, 10(-6)mol/L) and Isobavachin (IBA, 10(-7)mol/L) were selected to screen the differentiation-promoting activity on ES cells. Immunofluorescence staining with specific antibodies (ChAT, GABA) was used to evaluate the neuron subtypes. The cells treated with IBA showed neuron-like phenotype, but the cells treated with ICA did not exhibit the morphological changes. ES cells treated with IBA was further confirmed to be cholinergic and GABAergic neurons. Phenotypic screening with light microscope for molecules promoting neuronal differentiation is an effective method with advantages of less labor and material consuming and time saving, and false-positive results derived from immunofluorescence can be avoided. The method confirms that IBA is able to facilitate ES cells differentiating into neuronal cells, including cholinergic neurons and GABAergic neurons.

The flavonoid fisetin promotes osteoblasts differentiation through Runx2 transcriptional activity.

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Léotoing, Laurent; Davicco, Marie-Jeanne; Lebecque, Patrice; Wittrant, Yohann; Coxam, Véronique

2014-06-01

Flavonoids represent a group of polyphenolic compounds commonly found in daily nutrition with proven health benefits. Among this group, the flavonol fisetin has been previously shown to protect bone by repressing osteoclast differentiation. In the present study, we investigated the role of fisetin in regulating osteoblasts physiology. In vivo mice treated with LPSs exhibited osteoporosis features associated with a dramatic repression of osteoblast marker expression. In this model, inhibition of osteocalcin and type I collagen alpha 1 transcription was partially countered by a daily consumption of fisetin. Interestingly, in vitro, fisetin promoted both osteoblast alkaline phosphatase activity and mineralization process. To decipher how fisetin may exert its positive effect on osteoblastogenesis, we analyzed its ability to control the runt-related transcription factor 2 (Runx2), a key organizer in developing and maturing osteoblasts. While fisetin did not impact Runx2 mRNA and protein levels, it upregulated its transcriptional activity. Actually, fisetin stimulated the luciferase activity of a reporter plasmid driven by the osteocalcin gene promoter that contains Runx2 binding sites and promoted the mRNA expression of osteocalcin and type I collagen alpha 1 targets. Bone sparing properties of fisetin also rely on its positive influence on osteoblast differentiation and activity. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Survey of Differentially Methylated Promoters in Prostate Cancer Cell Lines

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Yipeng Wang

2005-08-01

Full Text Available DNA methylation, copy number in the genomes of three immortalized prostate epithelial, five cancer cell lines (LNCaP, PC3, PC3M, PC3M-Pro4, PC3MLN4 were compared using a microarray-based technique. Genomic DNA is cut with a methylation-sensitive enzyme Hpall, followed by linker ligation, polymerase chain reaction (PCR amplification, labeling, hybridization to an array of promoter sequences. Only those parts of the genomic DNA that have unmethylated restriction sites within a few hundred base pairs generate PCR products detectable on an array. Of 2732 promoter sequences on a test array, 504 (18.5% showed differential hybridization between immortalized prostate epithelial, cancer cell lines. Among candidate hypermethylated genes in cancer-derived lines, there were eight (CD44, CDKN1A, ESR1, PLAU, RARB, SFN, TNFRSF6, TSPY previously observed in prostate cancer, 13 previously known methylation targets in other cancers (ARHI, bcl-2, BRCA1, CDKN2C, GADD45A, MTAP, PGR, SLC26A4, SPARC, SYK, TJP2, UCHL1, WIT-1. The majority of genes that appear to be both differentially methylated, differentially regulated between prostate epithelial, cancer cell lines are novel methylation targets, including PAK6, RAD50, TLX3, PIR51, MAP2K5, INSR, FBN1, GG2-1, representing a rich new source of candidate genes used to study the role of DNA methylation in prostate tumors.

Fibronectin promotes differentiation of neural crest progenitors endowed with smooth muscle cell potential

International Nuclear Information System (INIS)

Costa-Silva, Bruno; Coelho da Costa, Meline; Melo, Fernanda Rosene; Neves, Cynara Mendes; Alvarez-Silva, Marcio; Calloni, Giordano Wosgrau; Trentin, Andrea Goncalves

2009-01-01

The neural crest (NC) is a model system used to investigate multipotency during vertebrate development. Environmental factors control NC cell fate decisions. Despite the well-known influence of extracellular matrix molecules in NC cell migration, the issue of whether they also influence NC cell differentiation has not been addressed at the single cell level. By analyzing mass and clonal cultures of mouse cephalic and quail trunk NC cells, we show for the first time that fibronectin (FN) promotes differentiation into the smooth muscle cell phenotype without affecting differentiation into glia, neurons, and melanocytes. Time course analysis indicated that the FN-induced effect was not related to massive cell death or proliferation of smooth muscle cells. Finally, by comparing clonal cultures of quail trunk NC cells grown on FN and collagen type IV (CLIV), we found that FN strongly increased both NC cell survival and the proportion of unipotent and oligopotent NC progenitors endowed with smooth muscle potential. In contrast, melanocytic progenitors were prominent in clonogenic NC cells grown on CLIV. Taken together, these results show that FN promotes NC cell differentiation along the smooth muscle lineage, and therefore plays an important role in fate decisions of NC progenitor cells

Nuclear Factor I-C promotes proliferation and differentiation of apical papilla-derived human stem cells in vitro

International Nuclear Information System (INIS)

Zhang, Jing; Wang, Zhihua; Jiang, Yong; Niu, Zhongying; Fu, Lei; Luo, Zhirong; Cooper, Paul R.; Smith, Anthony J.; He, Wenxi

2015-01-01

The transcription factor Nuclear Factor I-C (NFIC) has been implicated in the regulation of tooth root development, where it may be anticipated to impact on the behavior of stem cells from the apical papilla (SCAPs) and root odontoblast activity. We hypothesized that NFIC may provide an important target for promoting dentin/root regeneration. In the present study, the effects of NFIC on the proliferation and differentiation of SCAPs were investigated. Over-expression of NFIC increased cell proliferation, mineralization nodule formation and alkaline phosphatase (ALP) activity in SCAPs. Furthermore, NFIC up-regulated the mRNA levels of odontogenic-related markers, ALP, osteocalcin and collagen type I as well as dentin sialoprotein protein levels. In contrast, knockdown of NFIC by si-RNA inhibited the mineralization capacity of SCAPs and down-regulated the expression of odontogenic-related markers. In conclusion, the results indicated that upregulation of NFIC activity in SCAPs may promote osteo/odontoblastic differentiation of SCAPs. - Highlights: • NFIC promotes the proliferation of SCAPs in vitro. • NFIC promotes osteo/odontogenic differentiation of SCAPs in vitro. • Knockdown of NFIC inhibits odontogenic differentiation in SCAPs

Nuclear Factor I-C promotes proliferation and differentiation of apical papilla-derived human stem cells in vitro

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Zhang, Jing [State Key Laboratory of Military Stomatology, Department of Operative Dentistry & Endodontics, School of Stomatology, The Fourth Military Medical University, Xi' an (China); Stomatologic Hospital & College, Anhui Medical University, Key Lab of Oral Diseases Research of Anhui Province, Hefei (China); Wang, Zhihua; Jiang, Yong [State Key Laboratory of Military Stomatology, Department of Operative Dentistry & Endodontics, School of Stomatology, The Fourth Military Medical University, Xi' an (China); Niu, Zhongying [Treatment center of oral diseases, The 306th Hospital of People' s Liberation Army, Beijing (China); Fu, Lei; Luo, Zhirong [State Key Laboratory of Military Stomatology, Department of Operative Dentistry & Endodontics, School of Stomatology, The Fourth Military Medical University, Xi' an (China); Cooper, Paul R.; Smith, Anthony J. [Oral Biology, School of Dentistry, University of Birmingham, B4 6NN (United Kingdom); He, Wenxi, E-mail: hewenxi@fmmu.edu.cn [State Key Laboratory of Military Stomatology, Department of Operative Dentistry & Endodontics, School of Stomatology, The Fourth Military Medical University, Xi' an (China)

2015-03-15

The transcription factor Nuclear Factor I-C (NFIC) has been implicated in the regulation of tooth root development, where it may be anticipated to impact on the behavior of stem cells from the apical papilla (SCAPs) and root odontoblast activity. We hypothesized that NFIC may provide an important target for promoting dentin/root regeneration. In the present study, the effects of NFIC on the proliferation and differentiation of SCAPs were investigated. Over-expression of NFIC increased cell proliferation, mineralization nodule formation and alkaline phosphatase (ALP) activity in SCAPs. Furthermore, NFIC up-regulated the mRNA levels of odontogenic-related markers, ALP, osteocalcin and collagen type I as well as dentin sialoprotein protein levels. In contrast, knockdown of NFIC by si-RNA inhibited the mineralization capacity of SCAPs and down-regulated the expression of odontogenic-related markers. In conclusion, the results indicated that upregulation of NFIC activity in SCAPs may promote osteo/odontoblastic differentiation of SCAPs. - Highlights: • NFIC promotes the proliferation of SCAPs in vitro. • NFIC promotes osteo/odontogenic differentiation of SCAPs in vitro. • Knockdown of NFIC inhibits odontogenic differentiation in SCAPs.

Cell recognition molecule L1 promotes embryonic stem cell differentiation through the regulation of cell surface glycosylation

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Li, Ying [Department of Biochemistry and Molecular Biology, Dalian Medical University, Dalian 116044 (China); Department of Clinical Laboratory, Second Affiliated Hospital of Dalian Medical University, Dalian 116023 (China); Huang, Xiaohua [Department of Biochemistry and Molecular Biology, Dalian Medical University, Dalian 116044 (China); Department of Clinical Biochemistry, College of Laboratory Medicine, Dalian Medical University, Dalian 116044 (China); An, Yue [Department of Clinical Laboratory, Second Affiliated Hospital of Dalian Medical University, Dalian 116023 (China); Ren, Feng [Department of Biochemistry and Molecular Biology, Dalian Medical University, Dalian 116044 (China); Yang, Zara Zhuyun; Zhu, Hongmei; Zhou, Lei [The Key Laboratory of Stem Cell and Regenerative Medicine, Institute of Molecular and Clinical Medicine, Kunming Medical University, Kunming 650228 (China); Department of Anatomy and Developmental Biology, Monash University, Clayton 3800 (Australia); He, Xiaowen; Schachner, Melitta [Keck Center for Collaborative Neuroscience and Department of Cell Biology and Neuroscience, Rutgers University, New Brunswick, NJ (United States); Xiao, Zhicheng, E-mail: zhicheng.xiao@monash.edu [The Key Laboratory of Stem Cell and Regenerative Medicine, Institute of Molecular and Clinical Medicine, Kunming Medical University, Kunming 650228 (China); Department of Anatomy and Developmental Biology, Monash University, Clayton 3800 (Australia); Ma, Keli, E-mail: makeli666@aliyun.com [Department of Biochemistry and Molecular Biology, Dalian Medical University, Dalian 116044 (China); Li, Yali, E-mail: yalilipaper@gmail.com [Department of Biochemistry and Molecular Biology, Dalian Medical University, Dalian 116044 (China); Department of Anatomy, National University of Singapore, Singapore 119078 (Singapore)

2013-10-25

Highlights: •Down-regulating FUT9 and ST3Gal4 expression blocks L1-induced neuronal differentiation of ESCs. •Up-regulating FUT9 and ST3Gal4 expression in L1-ESCs depends on the activation of PLCγ. •L1 promotes ESCs to differentiate into neuron through regulating cell surface glycosylation. -- Abstract: Cell recognition molecule L1 (CD171) plays an important role in neuronal survival, migration, differentiation, neurite outgrowth, myelination, synaptic plasticity and regeneration after injury. Our previous study has demonstrated that overexpressing L1 enhances cell survival and proliferation of mouse embryonic stem cells (ESCs) through promoting the expression of FUT9 and ST3Gal4, which upregulates cell surface sialylation and fucosylation. In the present study, we examined whether sialylation and fucosylation are involved in ESC differentiation through L1 signaling. RNA interference analysis showed that L1 enhanced differentiation of ESCs into neurons through the upregulation of FUT9 and ST3Gal4. Furthermore, blocking the phospholipase Cγ (PLCγ) signaling pathway with either a specific PLCγ inhibitor or knockdown PLCγ reduced the expression levels of both FUT9 and ST3Gal4 mRNAs and inhibited L1-mediated neuronal differentiation. These results demonstrate that L1 promotes neuronal differentiation from ESCs through the L1-mediated enhancement of FUT9 and ST3Gal4 expression.

Cell recognition molecule L1 promotes embryonic stem cell differentiation through the regulation of cell surface glycosylation

International Nuclear Information System (INIS)

Li, Ying; Huang, Xiaohua; An, Yue; Ren, Feng; Yang, Zara Zhuyun; Zhu, Hongmei; Zhou, Lei; He, Xiaowen; Schachner, Melitta; Xiao, Zhicheng; Ma, Keli; Li, Yali

2013-01-01

Highlights: •Down-regulating FUT9 and ST3Gal4 expression blocks L1-induced neuronal differentiation of ESCs. •Up-regulating FUT9 and ST3Gal4 expression in L1-ESCs depends on the activation of PLCγ. •L1 promotes ESCs to differentiate into neuron through regulating cell surface glycosylation. -- Abstract: Cell recognition molecule L1 (CD171) plays an important role in neuronal survival, migration, differentiation, neurite outgrowth, myelination, synaptic plasticity and regeneration after injury. Our previous study has demonstrated that overexpressing L1 enhances cell survival and proliferation of mouse embryonic stem cells (ESCs) through promoting the expression of FUT9 and ST3Gal4, which upregulates cell surface sialylation and fucosylation. In the present study, we examined whether sialylation and fucosylation are involved in ESC differentiation through L1 signaling. RNA interference analysis showed that L1 enhanced differentiation of ESCs into neurons through the upregulation of FUT9 and ST3Gal4. Furthermore, blocking the phospholipase Cγ (PLCγ) signaling pathway with either a specific PLCγ inhibitor or knockdown PLCγ reduced the expression levels of both FUT9 and ST3Gal4 mRNAs and inhibited L1-mediated neuronal differentiation. These results demonstrate that L1 promotes neuronal differentiation from ESCs through the L1-mediated enhancement of FUT9 and ST3Gal4 expression

Electrical Stimulation Promotes Cardiac Differentiation of Human Induced Pluripotent Stem Cells

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Damián Hernández

2016-01-01

Full Text Available Background. Human induced pluripotent stem cells (iPSCs are an attractive source of cardiomyocytes for cardiac repair and regeneration. In this study, we aim to determine whether acute electrical stimulation of human iPSCs can promote their differentiation to cardiomyocytes. Methods. Human iPSCs were differentiated to cardiac cells by forming embryoid bodies (EBs for 5 days. EBs were then subjected to brief electrical stimulation and plated down for 14 days. Results. In iPS(Foreskin-2 cell line, brief electrical stimulation at 65 mV/mm or 200 mV/mm for 5 min significantly increased the percentage of beating EBs present by day 14 after plating. Acute electrical stimulation also significantly increased the cardiac gene expression of ACTC1, TNNT2, MYH7, and MYL7. However, the cardiogenic effect of electrical stimulation was not reproducible in another iPS cell line, CERA007c6. Beating EBs from control and electrically stimulated groups expressed various cardiac-specific transcription factors and contractile muscle markers. Beating EBs were also shown to cycle calcium and were responsive to the chronotropic agents, isoproterenol and carbamylcholine, in a concentration-dependent manner. Conclusions. Our results demonstrate that brief electrical stimulation can promote cardiac differentiation of human iPS cells. The cardiogenic effect of brief electrical stimulation is dependent on the cell line used.

ERG promotes the maintenance of hematopoietic stem cells by restricting their differentiation

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Knudsen, Kasper Jermiin; Rehn, Matilda Carolina; Hasemann, Marie Sigurd

2015-01-01

The balance between self-renewal and differentiation is crucial for the maintenance of hematopoietic stem cells (HSCs). Whereas numerous gene regulatory factors have been shown to control HSC self-renewal or drive their differentiation, we have relatively few insights into transcription factors...... and functional HSCs. Molecularly, we could demonstrate that ERG, in addition to promoting the expression of HSC self-renewal genes, also represses a group of MYC targets, thereby explaining why Erg loss closely mimics Myc overexpression. Consistently, the BET domain inhibitor CPI-203, known to repress Myc...... expression, confers a partial phenotypic rescue. In summary, ERG plays a critical role in coordinating the balance between self-renewal and differentiation of HSCs....

Unlike PPARγ, PPARα or PPARβ/δ activation does not promote human monocyte differentiation toward alternative macrophages

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Bouhlel, Mohamed Amine; Brozek, John; Derudas, Bruno; Zawadzki, Christophe; Jude, Brigitte; Staels, Bart; Chinetti-Gbaguidi, Giulia

2009-01-01

Macrophages adapt their response to micro-environmental signals. While Th1 cytokines promote pro-inflammatory M1 macrophages, Th2 cytokines promote an 'alternative' anti-inflammatory M2 macrophage phenotype. Peroxisome proliferator-activated receptors (PPARs) are ligand-activated transcription factors expressed in macrophages where they control the inflammatory response. It has been shown that PPARγ promotes the differentiation of monocytes into anti-inflammatory M2 macrophages in humans and mice, while a role for PPARβ/δ in this process has been reported only in mice and no data are available for PPARα. Here, we show that in contrast to PPARγ, expression of PPARα and PPARβ/δ overall does not correlate with the expression of M2 markers in human atherosclerotic lesions, whereas a positive correlation with genes of lipid metabolism exists. Moreover, unlike PPARγ, PPARα or PPARβ/δ activation does not influence human monocyte differentiation into M2 macrophages in vitro. Thus, PPARα and PPARβ/δ do not appear to modulate the alternative differentiation of human macrophages.

Selective AR Modulators that Distinguish Proliferative from Differentiative Gene Promoters

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2016-08-01

levels, and in some cases be useful in early stage disease or watchful waiting, and in other cases castration resistant prostate cancer (CRPC...dependent kinase inhibitor p21 gene through an androgen response element in the proximal promoter. Molecular endocrinology 13, 376 (Mar, 1999). 9...analyses and in mouse xenograft experiments, as planned. We will also continue to probe the molecular mechanism by which dox elicits these differential

EZH2 regulates neuroblastoma cell differentiation via NTRK1 promoter epigenetic modifications.

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Li, Zhenghao; Takenobu, Hisanori; Setyawati, Amallia Nuggetsiana; Akita, Nobuhiro; Haruta, Masayuki; Satoh, Shunpei; Shinno, Yoshitaka; Chikaraishi, Koji; Mukae, Kyosuke; Akter, Jesmin; Sugino, Ryuichi P; Nakazawa, Atsuko; Nakagawara, Akira; Aburatani, Hiroyuki; Ohira, Miki; Kamijo, Takehiko

2018-05-01

The polycomb repressor complex 2 molecule EZH2 is now known to play a role in essential cellular processes, namely, cell fate decisions, cell cycle regulation, senescence, cell differentiation, and cancer development/progression. EZH2 inhibitors have recently been developed; however, their effectiveness and underlying molecular mechanisms in many malignancies have not yet been elucidated in detail. Although the functional role of EZH2 in tumorigenesis in neuroblastoma (NB) has been investigated, mutations of EZH2 have not been reported. A Kaplan-Meier analysis on the event free survival and overall survival of NB patients indicated that the high expression of EZH2 correlated with an unfavorable prognosis. In order to elucidate the functional roles of EZH2 in NB tumorigenesis and its aggressiveness, we knocked down EZH2 in NB cell lines using lentivirus systems. The knockdown of EZH2 significantly induced NB cell differentiation, e.g., neurite extension, and the neuronal differentiation markers, NF68 and GAP43. EZH2 inhibitors also induced NB cell differentiation. We performed a comprehensive transcriptome analysis using Human Gene Expression Microarrays and found that NTRK1 (TrkA) is one of the EZH2-related suppression targets. The depletion of NTRK1 canceled EZH2 knockdown-induced NB cell differentiation. Our integrative methylome, transcriptome, and chromatin immunoprecipitation assays using NB cell lines and clinical samples clarified that the NTRK1 P1 and P2 promoter regions were regulated differently by DNA methylation and EZH2-related histone modifications. The NTRK1 transcript variants 1/2, which were regulated by EZH2-related H3K27me3 modifications at the P1 promoter region, were strongly expressed in favorable, but not unfavorable NB. The depletion and inhibition of EZH2 successfully induced NTRK1 transcripts and functional proteins. Collectively, these results indicate that EZH2 plays important roles in preventing the differentiation of NB cells and also

Differentiation-dependent activation of the human intestinal alkaline phosphatase promoter by HNF-4 in intestinal cells

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Olsen, Line; Bressendorff, Simon; Troelsen, Jesper T

2005-01-01

The intestinal alkaline phosphatase gene (ALPI) encodes a digestive brush-border enzyme, which is highly upregulated during small intestinal epithelial cell differentiation. To identify new putative promoter motifs responsible for the regulation of ALPI expression during differentiation of the en...

Senescence from glioma stem cell differentiation promotes tumor growth

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Ouchi, Rie; Okabe, Sachiko; Migita, Toshiro; Nakano, Ichiro; Seimiya, Hiroyuki

2016-01-01

Glioblastoma (GBM) is a lethal brain tumor composed of heterogeneous cellular populations including glioma stem cells (GSCs) and differentiated non-stem glioma cells (NSGCs). While GSCs are involved in tumor initiation and propagation, NSGCs' role remains elusive. Here, we demonstrate that NSGCs undergo senescence and secrete pro-angiogenic proteins, boosting the GSC-derived tumor formation in vivo. We used a GSC model that maintains stemness in neurospheres, but loses the stemness and differentiates into NSGCs upon serum stimulation. These NSGCs downregulated telomerase, shortened telomeres, and eventually became senescent. The senescent NSGCs released pro-angiogenic proteins, including vascular endothelial growth factors and senescence-associated interleukins, such as IL-6 and IL-8. Conditioned medium from senescent NSGCs promoted proliferation of brain microvascular endothelial cells, and mixed implantation of GSCs and senescent NSGCs into mice enhanced the tumorigenic potential of GSCs. The senescent NSGCs seem to be clinically relevant, because both clinical samples and xenografts of GBM contained tumor cells that expressed the senescence markers. Our data suggest that senescent NSGCs promote malignant progression of GBM in part via paracrine effects of the secreted proteins. - Highlights: • Non-stem glioma cells (NSGCs) lose telomerase and eventually become senescent. • Senescent NSGCs secrete pro-angiogenic proteins, such as VEGFs, IL-6, and IL-8. • Senescent NSGCs enhance the growth of brain microvascular endothelial cells. • Senescent NSGCs enhance the tumorigenic potential of glioma stem cells in vivo.

Senescence from glioma stem cell differentiation promotes tumor growth

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Ouchi, Rie [Division of Molecular Biotherapy, Cancer Chemotherapy Center, Japanese Foundation for Cancer Research, 3-8-31 Ariake, Koto-ku, Tokyo 135-8550 (Japan); Laboratory of Molecular Target Therapy of Cancer, Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, 3-8-31 Ariake, Koto-ku, Tokyo 135-8550 (Japan); Okabe, Sachiko; Migita, Toshiro [Division of Molecular Biotherapy, Cancer Chemotherapy Center, Japanese Foundation for Cancer Research, 3-8-31 Ariake, Koto-ku, Tokyo 135-8550 (Japan); Nakano, Ichiro [Department of Neurosurgery, Comprehensive Cancer Center, University of Alabama at Birmingham, 1824 6th Avenue South, Birmingham, AL 35233 (United States); Seimiya, Hiroyuki, E-mail: hseimiya@jfcr.or.jp [Division of Molecular Biotherapy, Cancer Chemotherapy Center, Japanese Foundation for Cancer Research, 3-8-31 Ariake, Koto-ku, Tokyo 135-8550 (Japan); Laboratory of Molecular Target Therapy of Cancer, Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, 3-8-31 Ariake, Koto-ku, Tokyo 135-8550 (Japan)

2016-02-05

Glioblastoma (GBM) is a lethal brain tumor composed of heterogeneous cellular populations including glioma stem cells (GSCs) and differentiated non-stem glioma cells (NSGCs). While GSCs are involved in tumor initiation and propagation, NSGCs' role remains elusive. Here, we demonstrate that NSGCs undergo senescence and secrete pro-angiogenic proteins, boosting the GSC-derived tumor formation in vivo. We used a GSC model that maintains stemness in neurospheres, but loses the stemness and differentiates into NSGCs upon serum stimulation. These NSGCs downregulated telomerase, shortened telomeres, and eventually became senescent. The senescent NSGCs released pro-angiogenic proteins, including vascular endothelial growth factors and senescence-associated interleukins, such as IL-6 and IL-8. Conditioned medium from senescent NSGCs promoted proliferation of brain microvascular endothelial cells, and mixed implantation of GSCs and senescent NSGCs into mice enhanced the tumorigenic potential of GSCs. The senescent NSGCs seem to be clinically relevant, because both clinical samples and xenografts of GBM contained tumor cells that expressed the senescence markers. Our data suggest that senescent NSGCs promote malignant progression of GBM in part via paracrine effects of the secreted proteins. - Highlights: • Non-stem glioma cells (NSGCs) lose telomerase and eventually become senescent. • Senescent NSGCs secrete pro-angiogenic proteins, such as VEGFs, IL-6, and IL-8. • Senescent NSGCs enhance the growth of brain microvascular endothelial cells. • Senescent NSGCs enhance the tumorigenic potential of glioma stem cells in vivo.

Wnt-10b, uniquely among Wnts, promotes epithelial differentiation and shaft growth

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Ouji, Yukiteru; Yoshikawa, Masahide; Moriya, Kei; Nishiofuku, Mariko; Matsuda, Ryosuke; Ishizaka, Shigeaki

2008-01-01

Although Wnts are expressed in hair follicles throughout life from embryo to adult, and considered to be critical for their development and maturation, their roles remain largely unknown. In the present study, we investigated the effects of Wnts (Wnt-3a, Wnt-5a, Wnt-10b, and Wnt-11) on epithelial cell differentiation using adult mouse-derived primary skin epithelial cell (MPSEC) cultures and hair growth using hair follicle organ cultures. Only Wnt-10b showed evident promotion of epithelial cell differentiation and hair shaft growth, in contrast to Wnt-3a, 5a, and 11. Our results suggest that Wnt-10b is unique and plays an important role in differentiation of epithelial cells in the hair follicle

Biphasic electrical currents stimulation promotes both proliferation and differentiation of fetal neural stem cells.

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Keun-A Chang

2011-04-01

Full Text Available The use of non-chemical methods to differentiate stem cells has attracted researchers from multiple disciplines, including the engineering and the biomedical fields. No doubt, growth factor based methods are still the most dominant of achieving some level of proliferation and differentiation control--however, chemical based methods are still limited by the quality, source, and amount of the utilized reagents. Well-defined non-chemical methods to differentiate stem cells allow stem cell scientists to control stem cell biology by precisely administering the pre-defined parameters, whether they are structural cues, substrate stiffness, or in the form of current flow. We have developed a culture system that allows normal stem cell growth and the option of applying continuous and defined levels of electric current to alter the cell biology of growing cells. This biphasic current stimulator chip employing ITO electrodes generates both positive and negative currents in the same culture chamber without affecting surface chemistry. We found that biphasic electrical currents (BECs significantly increased the proliferation of fetal neural stem cells (NSCs. Furthermore, BECs also promoted the differentiation of fetal NSCs into neuronal cells, as assessed using immunocytochemistry. Our results clearly show that BECs promote both the proliferation and neuronal differentiation of fetal NSCs. It may apply to the development of strategies that employ NSCs in the treatment of various neurodegenerative diseases, such as Alzheimer's and Parkinson's diseases.

A natural diarylheptanoid promotes neuronal differentiation via activating ERK and PI3K-Akt dependent pathways.

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Tang, G; Dong, X; Huang, X; Huang, X-J; Liu, H; Wang, Y; Ye, W-C; Shi, L

2015-09-10

Neuronal differentiation is a critical developmental process that determines accurate synaptic connection and circuit wiring. A wide variety of naturally occurring compounds have been shown as promising drug leads for the generation and differentiation of neurons. Here we report that a diarylheptanoid from the plant Alpinia officinarum, 7-(4-hydroxyphenyl)-1-phenyl-4E-hepten-3-one (Cpd 1), exhibited potent activities in neuronal differentiation and neurite outgrowth. Cpd 1 induced differentiation of neuroblastoma Neuro-2a cells into a neuron-like morphology, and accelerated the establishment of axon-dendrite polarization of cultured hippocampal neurons. Moreover, Cpd 1 promoted neurite extension in both Neuro-2a cells and neurons. We showed that the effects of Cpd 1 on neuronal differentiation and neurite growth were specifically dependent on the activation of extracellular signal-regulated kinases (ERKs) and phosphoinositide 3-kinase (PI3K)-Akt signaling pathways. Importantly, intraperitoneal administration of Cpd 1 promoted the differentiation of new-born progenitor cells into mature neurons in the adult hippocampal dentate gyrus. Collectively, this study identifies a naturally occurring diarylheptanoid with beneficial effects on neuronal differentiation and neurite outgrowth in vitro and in vivo. Copyright © 2015 IBRO. Published by Elsevier Ltd. All rights reserved.

Valproic acid promotes neuronal differentiation by induction of proneural factors in association with H4 acetylation.

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Yu, In Tag; Park, Jin-Yong; Kim, Sung Hyun; Lee, Jeong-Sik; Kim, Yong-Seok; Son, Hyeon

2009-02-01

Valproate (VPA) influences the proliferation and differentiation of neuronal cells. However, little is known about the downstream events, such as alterations in gene transcription, that are associated with cell fate choice. To determine whether VPA plays an instructive role in cell fate choice during hippocampal neurogenesis, the expression of genes involved in the cell cycle and neuronal differentiation was investigated. Treatment with VPA during the progenitor stages resulted in strong inhibition of cell proliferation and induction of neuronal differentiation, accompanied by increases in the expression of proneural transcription factors and in neuronal cell numbers. The increased expression of Ngn1, Math1 and p15 points to a shift towards neuronal fate in response to histone deacetylase inhibitors (HDACi). Chromatin immunoprecipitation (ChIP) analysis showed that acetylated histone H4 (Ac-H4) was associated with the Ngn1, Math1 and p15 promoters in cultured hippocampal neural progenitor cells. VPA-induced hippocampal neurogenesis was also accompanied by association of Ac-H4 with the Ngn1 promoter in hippocampal extracts. The discovery of an association between HDACi and the Ngn1, Math1 and p15 promoters extends the importance of HDAC inhibition as a key regulator of neuronal differentiation at the transcriptional level.

Active form Notch4 promotes the proliferation and differentiation of 3T3-L1 preadipocytes

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Lai, Peng-Yeh [Institute of Molecular Biology and Department of Life Science, National Chung Cheng University, Chiayi 621, Taiwan, ROC (China); Tsai, Chong-Bin [Institute of Molecular Biology and Department of Life Science, National Chung Cheng University, Chiayi 621, Taiwan, ROC (China); Department of Ophthalmology, Chiayi Christian Hospital, Chiayi 600, Taiwan, ROC (China); Tseng, Min-Jen, E-mail: biomjt@ccu.edu.tw [Institute of Molecular Biology and Department of Life Science, National Chung Cheng University, Chiayi 621, Taiwan, ROC (China)

2013-01-18

Highlights: ► Notch4IC modulates the ERK pathway and cell cycle to promote 3T3-L1 proliferation. ► Notch4IC facilitates 3T3-L1 differentiation by up-regulating proadipogenic genes. ► Notch4IC promotes proliferation during the early stage of 3T3-L1 adipogenesis. ► Notch4IC enhances differentiation during subsequent stages of 3T3-L1 adipogenesis. -- Abstract: Adipose tissue is composed of adipocytes, which differentiate from precursor cells in a process called adipogenesis. Many signal molecules are involved in the transcriptional control of adipogenesis, including the Notch pathway. Previous adipogenic studies of Notch have focused on Notch1 and HES1; however, the role of other Notch receptors in adipogenesis remains unclear. Q-RT-PCR analyses showed that the augmentation of Notch4 expression during the differentiation of 3T3-L1 preadipocytes was comparable to that of Notch1. To elucidate the role of Notch4 in adipogenesis, the human active form Notch4 (N4IC) was transiently transfected into 3T3-L1 cells. The expression of HES1, Hey1, C/EBPδ and PPARγ was up-regulated, and the expression of Pref-1, an adipogenic inhibitor, was down-regulated. To further characterize the effect of N4IC in adipogenesis, stable cells expressing human N4IC were established. The expression of N4IC promoted proliferation and enhanced differentiation of 3T3-L1 cells compared with those of control cells. These data suggest that N4IC promoted proliferation through modulating the ERK pathway and the cell cycle during the early stage of 3T3-L1 adipogenesis and facilitated differentiation through up-regulating adipogenic genes such as C/EBPα, PPARγ, aP2, LPL and HSL during the middle and late stages of 3T3-L1 adipogenesis.

The ubiquitin ligase ASB4 promotes trophoblast differentiation through the degradation of ID2.

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W H Davin Townley-Tilson

Full Text Available Vascularization of the placenta is a critical developmental process that ensures fetal viability. Although the vascular health of the placenta affects both maternal and fetal well being, relatively little is known about the early stages of placental vascular development. The ubiquitin ligase Ankyrin repeat, SOCS box-containing 4 (ASB4 promotes embryonic stem cell differentiation to vascular lineages and is highly expressed early in placental development. The transcriptional regulator Inhibitor of DNA binding 2 (ID2 negatively regulates vascular differentiation during development and is a target of many ubiquitin ligases. Due to their overlapping spatiotemporal expression pattern in the placenta and contrasting effects on vascular differentiation, we investigated whether ASB4 regulates ID2 through its ligase activity in the placenta and whether this activity mediates vascular differentiation. In mouse placentas, ASB4 expression is restricted to a subset of cells that express both stem cell and endothelial markers. Placentas that lack Asb4 display immature vascular patterning and retain expression of placental progenitor markers, including ID2 expression. Using JAR placental cells, we determined that ASB4 ubiquitinates and represses ID2 expression in a proteasome-dependent fashion. Expression of ASB4 in JAR cells and primary isolated trophoblast stem cells promotes the expression of differentiation markers. In functional endothelial co-culture assays, JAR cells ectopically expressing ASB4 increased endothelial cell turnover and stabilized endothelial tube formation, both of which are hallmarks of vascular differentiation within the placenta. Co-transfection of a degradation-resistant Id2 mutant with Asb4 inhibits both differentiation and functional responses. Lastly, deletion of Asb4 in mice induces a pathology that phenocopies human pre-eclampsia, including hypertension and proteinuria in late-stage pregnant females. These results indicate that

Ferulic acid promotes survival and differentiation of neural stem cells to prevent gentamicin-induced neuronal hearing loss.

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Gu, Lintao; Cui, Xinhua; Wei, Wei; Yang, Jia; Li, Xuezhong

2017-11-15

Neural stem cells (NSCs) have exhibited promising potential in therapies against neuronal hearing loss. Ferulic acid (FA) has been widely reported to enhance neurogenic differentiation of different stem cells. We investigated the role of FA in promoting NSC transplant therapy to prevent gentamicin-induced neuronal hearing loss. NSCs were isolated from mouse cochlear tissues to establish in vitro culture, which were then treated with FA. The survival and differentiation of NSCs were evaluated. Subsequently, neurite outgrowth and excitability of the in vitro neuronal network were assessed. Gentamicin was used to induce neuronal hearing loss in mice, in the presence and absence of FA, followed by assessments of auditory brainstem response (ABR) and distortion product optoacoustic emissions (DPOAE) amplitude. FA promoted survival, neurosphere formation and differentiation of NSCs, as well as neurite outgrowth and excitability of in vitro neuronal network. Furthermore, FA restored ABR threshold shifts and DPOAE in gentamicin-induced neuronal hearing loss mouse model in vivo. Our data, for the first time, support potential therapeutic efficacy of FA in promoting survival and differentiation of NSCs to prevent gentamicin-induced neuronal hearing loss. Copyright © 2017 Elsevier Inc. All rights reserved.

BMS-777607 promotes megakaryocytic differentiation and induces polyploidization in the CHRF-288-11 cells.

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Nurhayati, Retno Wahyu; Ojima, Yoshihiro; Taya, Masahito

2015-04-01

Introduction of a polyploidy inducer is a promising strategy to achieve a high level of polyploidization during megakaryocytic (MK) differentiation. Here, we report that a multi-kinase inhibitor, BMS-777607, is a potent polyploidy inducer for elevating high ploidy cell formation in the MK-differentiated CHRF-288-11 (CHRF) cells. Our result showed that BMS-777607 strongly inhibited cell division without affecting cell viability when detected at day 1 after treatment. As a consequence, the high ploidy (≥8N) cells were accumulated in culture for 8 days, with an increase from 16.2 to 75.2 % of the total cell population. The elevated polyploidization was accompanied by the increased expression level of MK marker, CD41 (platelet glycoprotein IIb/IIIa, GPIIb/IIIa), suggesting that BMS-777607 promoted both polyploidization and commitment of MK-differentiated CHRF cells. Platelet-like fragments (PFs) were released by mature CHRF cells. Based on a flow cytometry assay, it was found that the PFs produced from BMS-777607-treated cells tended to have larger size and higher expression of GPIIb/IIIa, a receptor for platelet adhesion. Taken together, these results suggested that BMS-777607 promoted MK differentiation of CHRF cells and increased the functional property of platelet-like fragments.

Wnt-10b promotes differentiation of skin epithelial cells in vitro

International Nuclear Information System (INIS)

Ouji, Yukiteru; Yoshikawa, Masahide; Shiroi, Akira; Ishizaka, Shigeaki

2006-01-01

To evaluate the role of Wnt-10b in epithelial differentiation, we investigated the effects of Wnt-10b on adult mouse-derived primary skin epithelial cells (MPSEC). Recombinant Wnt-10b protein (rWnt-10b) was prepared using a gene engineering technique and MPSEC were cultured in its presence, which resulted in morphological changes from cuboidal to spindle-shaped and inhibited their proliferation. Further, involvement of the canonical Wnt signal pathway was also observed. MPSEC treated with rWnt-10b showed characteristics of the hair shaft and inner root sheath of the hair follicle, in results of Ayoub Shklar staining and immunocytochemistry. Further, the cells expressed mRNA for differentiated epithelial cells, including keratin 1, keratin 2, loricrin, mHa5, and mHb5, in association with a decreased expression of the basal cell marker keratin 5. These results suggest that Wnt-10b promotes the differentiation of MPSEC

Suppression of autophagy by extracellular vesicles promotes myofibroblast differentiation in COPD pathogenesis

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Yu Fujita

2015-11-01

Full Text Available Extracellular vesicles (EVs, such as exosomes and microvesicles, encapsulate proteins and microRNAs (miRNAs as new modulators of both intercellular crosstalk and disease pathogenesis. The composition of EVs is modified by various triggers to maintain physiological homeostasis. In response to cigarette smoke exposure, the lungs develop emphysema, myofibroblast accumulation and airway remodelling, which contribute to chronic obstructive pulmonary disease (COPD. However, the lung disease pathogenesis through modified EVs in stress physiology is not understood. Here, we investigated an EV-mediated intercellular communication mechanism between primary human bronchial epithelial cells (HBECs and lung fibroblasts (LFs and discovered that cigarette smoke extract (CSE-induced HBEC-derived EVs promote myofibroblast differentiation in LFs. Thorough evaluations of the modified EVs and COPD lung samples showed that cigarette smoke induced relative upregulation of cellular and EV miR-210 expression of bronchial epithelial cells. Using co-culture assays, we showed that HBEC-derived EV miR-210 promotes myofibroblast differentiation in LFs. Surprisingly, we found that miR-210 directly regulates autophagy processes via targeting ATG7, and expression levels of miR-210 are inversely correlated with ATG7 expression in LFs. Importantly, autophagy induction was significantly decreased in LFs from COPD patients, and silencing ATG7 in LFs led to myofibroblast differentiation. These findings demonstrate that CSE triggers the modification of EV components and identify bronchial epithelial cell-derived miR-210 as a paracrine autophagy mediator of myofibroblast differentiation that has potential as a therapeutic target for COPD. Our findings show that stressor exposure changes EV compositions as emerging factors, potentially controlling pathological disorders such as airway remodelling in COPD.

Differentiation-Dependent KLF4 Expression Promotes Lytic Epstein-Barr Virus Infection in Epithelial Cells.

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Dhananjay M Nawandar

2015-10-01

Full Text Available Epstein-Barr virus (EBV is a human herpesvirus associated with B-cell and epithelial cell malignancies. EBV lytically infects normal differentiated oral epithelial cells, where it causes a tongue lesion known as oral hairy leukoplakia (OHL in immunosuppressed patients. However, the cellular mechanism(s that enable EBV to establish exclusively lytic infection in normal differentiated oral epithelial cells are not currently understood. Here we show that a cellular transcription factor known to promote epithelial cell differentiation, KLF4, induces differentiation-dependent lytic EBV infection by binding to and activating the two EBV immediate-early gene (BZLF1 and BRLF1 promoters. We demonstrate that latently EBV-infected, telomerase-immortalized normal oral keratinocyte (NOKs cells undergo lytic viral reactivation confined to the more differentiated cell layers in organotypic raft culture. Furthermore, we show that endogenous KLF4 expression is required for efficient lytic viral reactivation in response to phorbol ester and sodium butyrate treatment in several different EBV-infected epithelial cell lines, and that the combination of KLF4 and another differentiation-dependent cellular transcription factor, BLIMP1, is highly synergistic for inducing lytic EBV infection. We confirm that both KLF4 and BLIMP1 are expressed in differentiated, but not undifferentiated, epithelial cells in normal tongue tissue, and show that KLF4 and BLIMP1 are both expressed in a patient-derived OHL lesion. In contrast, KLF4 protein is not detectably expressed in B cells, where EBV normally enters latent infection, although KLF4 over-expression is sufficient to induce lytic EBV reactivation in Burkitt lymphoma cells. Thus, KLF4, together with BLIMP1, plays a critical role in mediating lytic EBV reactivation in epithelial cells.

Deciphering the Role of Sulfonated Unit in Heparin-Mimicking Polymer to Promote Neural Differentiation of Embryonic Stem Cells.

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Lei, Jiehua; Yuan, Yuqi; Lyu, Zhonglin; Wang, Mengmeng; Liu, Qi; Wang, Hongwei; Yuan, Lin; Chen, Hong

2017-08-30

Glycosaminoglycans (GAGs), especially heparin and heparan sulfate (HS), hold great potential for inducing the neural differentiation of embryonic stem cells (ESCs) and have brought new hope for the treatment of neurological diseases. However, the disadvantages of natural heparin/HS, such as difficulty in isolating them with a sufficient amount, highly heterogeneous structure, and the risk of immune responses, have limited their further therapeutic applications. Thus, there is a great demand for stable, controllable, and well-defined synthetic alternatives of heparin/HS with more effective biological functions. In this study, based upon a previously proposed unit-recombination strategy, several heparin-mimicking polymers were synthesized by integrating glucosamine-like 2-methacrylamido glucopyranose monomers (MAG) with three sulfonated units in different structural forms, and their effects on cell proliferation, the pluripotency, and the differentiation of ESCs were carefully studied. The results showed that all the copolymers had good cytocompatibility and displayed much better bioactivity in promoting the neural differentiation of ESCs as compared to natural heparin; copolymers with different sulfonated units exhibited different levels of promoting ability; among them, copolymer with 3-sulfopropyl acrylate (SPA) as a sulfonated unit was the most potent in promoting the neural differentiation of ESCs; the promoting effect is dependent on the molecular weight and concentration of P(MAG-co-SPA), with the highest levels occurring at the intermediate molecular weight and concentration. These results clearly demonstrated that the sulfonated unit in the copolymers played an important role in determining the promoting effect on ESCs' neural differentiation; SPA was identified as the most potent sulfonated unit for copolymer with the strongest promoting ability. The possible reason for sulfonated unit structure as a vital factor influencing the ability of the copolymers

Six1 overexpression at early stages of HPV16-mediated transformation of human keratinocytes promotes differentiation resistance and EMT

International Nuclear Information System (INIS)

Xu, Hanwen; Pirisi, Lucia; Creek, Kim E.

2015-01-01

Previous studies in our laboratory discovered that SIX1 mRNA expression increased during in vitro progression of HPV16-immortalized human keratinocytes (HKc/HPV16) toward a differentiation-resistant (HKc/DR) phenotype. In this study, we explored the role of Six1 at early stages of HPV16-mediated transformation by overexpressing Six1 in HKc/HPV16. We found that Six1 overexpression in HKc/HPV16 increased cell proliferation and promoted cell migration and invasion by inducing epithelial–mesenchymal transition (EMT). Moreover, the overexpression of Six1 in HKc/HPV16 resulted in resistance to serum and calcium-induced differentiation, which is the hallmark of the HKc/DR phenotype. Activation of MAPK in HKc/HPV16 overexpressing Six1 is linked to resistance to calcium-induced differentiation. In conclusion, this study determined that Six1 overexpression resulted in differentiation resistance and promoted EMT at early stages of HPV16-mediated transformation of human keratinocytes. - Highlights: • Six1 expression increases during HPV16-mediated transformation. • Six1 overexpression causes differentiation resistance in HPV16-immortalized cells. • Six1 overexpression in HPV16-immortalized keratinocytes activates MAPK. • Activation of MAPK promotes EMT and differentiation resistance. • Six1 overexpression reduces Smad-dependent TGF-β signaling

Tributyltin Differentially Promotes Development of a Phenotypically Distinct Adipocyte

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Regnier, Shane M.; El-Hashani, Essam; Kamau, Wakanene; Zhang, Xiaojie; Massad, Nicole L.; Sargis, Robert M.

2015-01-01

Objective Environmental endocrine disrupting chemicals (EDCs) are increasingly implicated in the pathogenesis of obesity. Evidence implicates various EDCs as being pro-adipogenic, including tributyltin (TBT), which activates the peroxisome proliferator activated receptor-γ (PPARγ). However, the conditions required for TBT-induced adipogenesis and its functional consequences are incompletely known. Methods The co-stimulatory conditions necessary for preadipocyte-to-adipocyte differentiation were compared between TBT and the pharmacological PPARγ agonist troglitazone (Trog) in the 3T3-L1 cell line; basal and insulin-stimulated glucose uptake were assessed using radiolabeled 2-deoxyglucose. Results TBT enhanced expression of the adipocyte marker C/EBPα with co-exposure to either isobutylmethylxanthine or insulin in the absence of other adipogenic stimuli. Examination of several adipocyte-specific proteins revealed that TBT and Trog differentially affected protein expression despite comparable PPARγ stimulation. In particular, TBT reduced adiponectin expression upon maximal adipogenic stimulation. Under submaximal stimulation, TBT and Trog differentially promoted adipocyte-specific gene expression despite similar lipid accumulation. Moreover, TBT attenuated Trog-induced adipocyte gene expression under conditions of co-treatment. Finally, TBT-induced adipocytes exhibited altered glucose metabolism, with increased basal glucose uptake. Conclusions TBT-induced adipocytes are functionally distinct from those generated by a pharmacological PPARγ agonist, suggesting that obesogen-induced adipogenesis may generate dysfunctional adipocytes with the capacity to deleteriously affect global energy homeostasis. PMID:26243053

Tributyltin differentially promotes development of a phenotypically distinct adipocyte.

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Regnier, Shane M; El-Hashani, Essam; Kamau, Wakanene; Zhang, Xiaojie; Massad, Nicole L; Sargis, Robert M

2015-09-01

Environmental endocrine disrupting chemicals (EDCs) are increasingly implicated in the pathogenesis of obesity. Evidence implicates various EDCs as being proadipogenic, including tributyltin (TBT), which activates the peroxisome proliferator activated receptor-γ (PPARγ). However, the conditions required for TBT-induced adipogenesis and its functional consequences are incompletely known. The costimulatory conditions necessary for preadipocyte-to-adipocyte differentiation were compared between TBT and the pharmacological PPARγ agonist troglitazone (Trog) in the 3T3-L1 cell line; basal and insulin-stimulated glucose uptake were assessed using radiolabeled 2-deoxyglucose. TBT enhanced expression of the adipocyte marker C/EBPα with coexposure to either isobutylmethylxanthine or insulin in the absence of other adipogenic stimuli. Examination of several adipocyte-specific proteins revealed that TBT and Trog differentially affected protein expression despite comparable PPARγ stimulation. In particular, TBT reduced adiponectin expression upon maximal adipogenic stimulation. Under submaximal stimulation, TBT and Trog differentially promoted adipocyte-specific gene expression despite similar lipid accumulation. Moreover, TBT attenuated Trog-induced adipocyte gene expression under conditions of cotreatment. Finally, TBT-induced adipocytes exhibited altered glucose metabolism, with increased basal glucose uptake. TBT-induced adipocytes are functionally distinct from those generated by a pharmacological PPARγ agonist, suggesting that obesogen-induced adipogenesis may generate dysfunctional adipocytes with the capacity to deleteriously affect global energy homeostasis. © 2015 The Obesity Society.

MiR-217 is down-regulated in psoriasis and promotes keratinocyte differentiation via targeting GRHL2

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Zhu, Haigang; Hou, Liyue; Liu, Jingjing; Li, Zhiming

2016-01-01

MiR-217 is a well-known tumor suppressor, and its down-regulation has been shown in a wide range of solid and leukaemic cancers. However, the biological role of miR-217 in psoriasis pathogenesis, especially in keratinocyte hyperproliferation and differentiation, is not clearly understood. In this study, we found the expression of miR-217 was markedly down-regulated in psoriasis keratinocytes of psoriatic patients. In addition, overexpression of miR-217 inhibited the proliferation and promoted the differentiation of primary human keratinocytes. On the contrary, inhibition of endogenous miR-217 increased cell proliferation and delayed differentiation. Furthermore, Grainyhead-like 2 (GRHL2) was identified as a direct target of miR-217 by luciferase reporter assay. The expression of miR-217 and GRHL2 was inversely correlated in both transfected keratinocytes and in psoriasis lesional skin. Moreover, knocking down GRHL2 expression by siRNA enhanced keratinocyte differentiation. Taken together, our results demonstrate a role for miR-217 in the regulation of keratinocyte differentiation, partially through the regulation of GRHL2. - Highlights: • miR-217 is down-regulated in psoriasis skin lesions. • miR-217 inhibits the proliferation and promotes differentiation of keratinocytes. • GRHL2 is a novel target of miR-217 in keratinocytes. • GRHL2 is up-regulated and inversely correlated with miR-217 in psoriasis skin lesions.

MiR-217 is down-regulated in psoriasis and promotes keratinocyte differentiation via targeting GRHL2

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Zhu, Haigang; Hou, Liyue; Liu, Jingjing; Li, Zhiming, E-mail: lizm_1001@sina.com

2016-02-26

MiR-217 is a well-known tumor suppressor, and its down-regulation has been shown in a wide range of solid and leukaemic cancers. However, the biological role of miR-217 in psoriasis pathogenesis, especially in keratinocyte hyperproliferation and differentiation, is not clearly understood. In this study, we found the expression of miR-217 was markedly down-regulated in psoriasis keratinocytes of psoriatic patients. In addition, overexpression of miR-217 inhibited the proliferation and promoted the differentiation of primary human keratinocytes. On the contrary, inhibition of endogenous miR-217 increased cell proliferation and delayed differentiation. Furthermore, Grainyhead-like 2 (GRHL2) was identified as a direct target of miR-217 by luciferase reporter assay. The expression of miR-217 and GRHL2 was inversely correlated in both transfected keratinocytes and in psoriasis lesional skin. Moreover, knocking down GRHL2 expression by siRNA enhanced keratinocyte differentiation. Taken together, our results demonstrate a role for miR-217 in the regulation of keratinocyte differentiation, partially through the regulation of GRHL2. - Highlights: • miR-217 is down-regulated in psoriasis skin lesions. • miR-217 inhibits the proliferation and promotes differentiation of keratinocytes. • GRHL2 is a novel target of miR-217 in keratinocytes. • GRHL2 is up-regulated and inversely correlated with miR-217 in psoriasis skin lesions.

Micro-Topographies Promote Late Chondrogenic Differentiation Markers in the ATDC5 Cell Line.

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Le, Bach Q; Vasilevich, Aliaksei; Vermeulen, Steven; Hulshof, Frits; Stamatialis, Dimitrios F; van Blitterswijk, Clemens A; de Boer, Jan

2017-05-01

Chemical and mechanical cues are well-established influencers of in vitro chondrogenic differentiation of ATDC5 cells. Here, we investigate the role of topographical cues in this differentiation process, a study not been explored before. Previously, using a library of surface micro-topographies we found some distinct patterns that induced alkaline phosphatase (ALP) production in human mesenchymal stromal cells. ALP is also a marker for hypertrophy, the end stage of chondrogenic differentiation preceding bone formation. Thus, we hypothesized that these patterns could influence end-stage chondrogenic differentiation of ATDC5 cells. In this study, we randomly selected seven topographies among the ALP influencing hits. Cells grown on these surfaces displayed varying nuclear shape and actin filament structure. When stimulated with insulin-transferrin-selenium (ITS) medium, nodule formation occurred and in some cases showed alignment to the topographical patterns. Gene expression analysis of cells growing on topographical surfaces in the presence of ITS medium revealed a downregulation of early markers and upregulation of late markers of chondrogenic differentiation compared to cells grown on a flat surface. In conclusion, we demonstrated that surface topography in addition to other cues can promote hypertrophic differentiation suitable for bone tissue engineering.

Downregulation of adenomatous polyposis coli by microRNA-663 promotes odontogenic differentiation through activation of Wnt/beta-catenin signaling

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Kim, Jae-Sung; Park, Min-Gyeong; Lee, Seul Ah; Park, Sun-Young; Kim, Heung-Joong; Yu, Sun-Kyoung; Kim, Chun Sung; Kim, Su-Gwan; Oh, Ji-Su; You, Jae-Seek; Kim, Jin-Soo; Seo, Yo-Seob [Oral Biology Research Institute, School of Dentistry, Chosun University, Gwangju 501-759 (Korea, Republic of); Chun, Hong Sung [Department of Biomedical Science, Chosun University, Gwangju 501-759 (Korea, Republic of); Park, Joo-Cheol [Department of Oral Histology-Developmental Biology, School of Dentistry and Dental Research Institute, BK 21, Seoul National University, Seoul 110-749 (Korea, Republic of); Kim, Do Kyung, E-mail: kdk@chosun.ac.kr [Oral Biology Research Institute, School of Dentistry, Chosun University, Gwangju 501-759 (Korea, Republic of)

2014-04-18

Highlights: • miR-663 is significantly up-regulated during MDPC-23 odontoblastic cell differentiation. • miR-663 accelerates mineralization in MDPC-23 odontoblastic cells without cell proliferation. • miR-663 promotes odontoblastic cell differentiation by targeting APC and activating Wnt/β-catenin signaling in MDPC-23 cells. - Abstract: MicroRNAs (miRNAs) regulate cell differentiation by inhibiting mRNA translation or by inducing its degradation. However, the role of miRNAs in odontogenic differentiation is largely unknown. In this present study, we observed that the expression of miR-663 increased significantly during differentiation of MDPC-23 cells to odontoblasts. Furthermore, up-regulation of miR-663 expression promoted odontogenic differentiation and accelerated mineralization without proliferation in MDPC-23 cells. In addition, target gene prediction for miR-663 revealed that the mRNA of the adenomatous polyposis coli (APC) gene, which is associated with the Wnt/β-catenin signaling pathway, has a miR-663 binding site in its 3′-untranslated region (3′UTR). Furthermore, APC expressional was suppressed significantly by miR-663, and this down-regulation of APC expression triggered activation of Wnt/β-catenin signaling through accumulation of β-catenin in the nucleus. Taken together, these findings suggest that miR-663 promotes differentiation of MDPC-23 cells to odontoblasts by targeting APC-mediated activation of Wnt/β-catenin signaling. Therefore, miR-663 can be considered a critical regulator of odontoblast differentiation and can be utilized for developing miRNA-based therapeutic agents.

Vitamin K2 promotes mesenchymal stem cell differentiation by inhibiting miR‑133a expression.

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Zhang, Yuelei; Weng, Shiyang; Yin, Junhui; Ding, Hao; Zhang, Changqing; Gao, Youshui

2017-05-01

Vitamin K2 has been demonstrated to promote the osteogenic differentiation of mesenchymal stem cells; however, the mechanisms underlying this effect remain unclear. As microRNA (miR)‑133a has been identified as a negative regulator of osteogenic differentiation, the present study hypothesized that vitamin K2 promoted osteogenesis by inhibiting miR‑133a. Using human bone marrow stromal cells (hBMSCs) overexpressing miR‑133a, or a control, the expression levels of osteogenesis‑associated proteins, including runt‑related transcription factor 2, alkaline phosphatase and osteocalcin, were analyzed. miR‑133a significantly suppressed the osteogenic differentiation of hBMSCs. To determine the effect of vitamin K2 on miR‑133a expression and osteogenesis, hBMSCs were treated with vitamin K2. Vitamin K2 inhibited miR‑133a expression, which was accompanied by enhanced osteogenic differentiation. Furthermore, the expression levels of vitamin K epoxide reductase complex subunit 1, the key protein in γ‑carboxylation, were downregulated by miR‑133a overexpression and upregulated by vitamin K2 treatment, indicating a positive feedback on γ‑carboxylation. The results of the present study suggested that vitamin K2 targets miR‑133a to regulate osteogenesis.

Activation of GLP-1 Receptor Promotes Bone Marrow Stromal Cell Osteogenic Differentiation through β-Catenin

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Jingru Meng

2016-04-01

Full Text Available Glucagon-like peptide 1 (GLP-1 plays an important role in regulating bone remodeling, and GLP-1 receptor agonist shows a positive relationship with osteoblast activity. However, GLP-1 receptor is not found in osteoblast, and the mechanism of GLP-1 receptor agonist on regulating bone remodeling is unclear. Here, we show that the GLP-1 receptor agonist exendin-4 (Ex-4 promoted bone formation and increased bone mass and quality in a rat unloading-induced bone loss model. These functions were accompanied by an increase in osteoblast number and serum bone formation markers, while the adipocyte number was decreased. Furthermore, GLP-1 receptor was detected in bone marrow stromal cells (BMSCs, but not in osteoblast. Activation of GLP-1 receptor by Ex-4 promoted the osteogenic differentiation and inhibited BMSC adipogenic differentiation through regulating PKA/β-catenin and PKA/PI3K/AKT/GSK3β signaling. These findings reveal that GLP-1 receptor regulates BMSC osteogenic differentiation and provide a molecular basis for therapeutic potential of GLP-1 against osteoporosis.

Strontium Promotes Cementoblasts Differentiation through Inhibiting Sclerostin Expression In Vitro

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Xingfu Bao

2014-01-01

Full Text Available Cementogenesis, performed by cementoblasts, is important for the repair of root resorption caused by orthodontic treatment. Based on recent studies, strontium has been applied for osteoporosis treatment due to its positive effect on osteoblasts. Although promising, the effect of strontium on cementoblasts is still unclear. So the aim of this research was to clarify and investigate the effect of strontium on cementogenesis via employing cementoblasts as model. A series of experiments including MTT, alkaline phosphatase activity, gene analysis, alizarin red staining, and western blot were carried out to evaluate the proliferation and differentiation of cementoblasts. In addition, expression of sclerostin was checked to analyze the possible mechanism. Our results show that strontium inhibits the proliferation of cementoblasts with a dose dependent manner; however, it can promote the differentiation of cementoblasts via downregulating sclerostin expression. Taking together, strontium may facilitate cementogenesis and benefit the treatment of root resorption at a low dose.

MicroRNA-9 promotes the neuronal differentiation of rat bone marrow mesenchymal stem cells by activating autophagy

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Guang-yu Zhang

2015-01-01

Full Text Available MicroRNA-9 (miR-9 has been shown to promote the differentiation of bone marrow mesenchymal stem cells into neuronal cells, but the precise mechanism is unclear. Our previous study confirmed that increased autophagic activity improved the efficiency of neuronal differentiation in bone marrow mesenchymal stem cells. Accumulating evidence reveals that miRNAs adjust the autophagic pathways. This study used miR-9-1 lentiviral vector and miR-9-1 inhibitor to modulate the expression level of miR-9. Autophagic activity and neuronal differentiation were measured by the number of light chain-3 (LC3-positive dots, the ratio of LC3-II/LC3, and the expression levels of the neuronal markers enolase and microtubule-associated protein 2. Results showed that LC3-positive dots, the ratio of LC3-II/LC3, and expression of neuron specific enolase and microtubule-associated protein 2 increased in the miR-9 + group. The above results suggest that autophagic activity increased and bone marrow mesenchymal stem cells were prone to differentiate into neuronal cells when miR-9 was overexpressed, demonstrating that miR-9 can promote neuronal differentiation by increasing autophagic activity.

Aryl hydrocarbon receptor downregulates MYCN expression and promotes cell differentiation of neuroblastoma.

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Pei-Yi Wu

Full Text Available Neuroblastoma (NB is the most common malignant disease of infancy. MYCN amplification is a prognostic factor for NB and is a sign of highly malignant disease and poor patient prognosis. In this study, we aimed to investigate novel MYCN-related genes and assess how they affect NB cell behavior. The different gene expression found in 10 MYCN amplification NB tumors and 10 tumors with normal MYCN copy number were analyzed using tissue oligonucleotide microarrays. Ingenuity Pathway Analysis was subsequently performed to identify the potential genes involved in MYCN regulation pathways. Aryl hydrocarbon receptor (AHR, a receptor for dioxin-like compounds, was found to be inversely correlated with MYCN expression in NB tissues. This correlation was confirmed in a further 14 human NB samples. Moreover, AHR expression in NB tumors was found to correlate highly with histological grade of differentiation. In vitro studies revealed that AHR overexpression in NB cells induced spontaneous cell differentiation. In addition, it was found that ectopic expression of AHR suppressed MYCN promoter activity resulting in downregulation of MYCN expression. The suppression effect of AHR on the transcription of MYCN was compensated for by E2F1 overexpression, indicating that E2F1 is involved in the AHR-regulating MYCN pathway. Furthermore, AHR shRNA promotes the expression of E2F1 and MYCN in NB cells. These findings suggest that AHR is one of the upstream regulators of MYCN. Through the modulation of E2F1, AHR regulates MYCN gene expression, which may in turn affect NB differentiation.

Gelatin-Derived Graphene–Silicate Hybrid Materials Are Biocompatible and Synergistically Promote BMP9-Induced Osteogenic Differentiation of Mesenchymal Stem Cells

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Zou, Yulong [Department of Orthopaedic; Molecular Oncology Laboratory, Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, Illinois 60637, United States; Qazvini, Nader Taheri [Institute for Molecular Engineering, The University of Chicago, Chicago, Illinois 60637, United States; Argonne National Laboratory, Argonne, Illinois 60439, United States; Zane, Kylie [Institute for Molecular Engineering, The University of Chicago, Chicago, Illinois 60637, United States; Sadati, Monirosadat [Institute for Molecular Engineering, The University of Chicago, Chicago, Illinois 60637, United States; Argonne National Laboratory, Argonne, Illinois 60439, United States; Wei, Qiang [Molecular Oncology Laboratory, Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, Illinois 60637, United States; Ministry of Education Key Laboratory of; Liao, Junyi [Molecular Oncology Laboratory, Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, Illinois 60637, United States; Ministry of Education Key Laboratory of; Fan, Jiaming [Molecular Oncology Laboratory, Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, Illinois 60637, United States; Ministry of Education Key Laboratory of; Song, Dongzhe [Molecular Oncology Laboratory, Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, Illinois 60637, United States; Department of Conservative Dentistry and Endodontics, West China School of Stomatology, Sichuan University, Chengdu 610041, China; Liu, Jianxiang [Molecular Oncology Laboratory, Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, Illinois 60637, United States; Department; amp, Technology, Wuhan 430022, China; Ma, Chao [Molecular Oncology Laboratory, Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, Illinois 60637, United States; Departments of Neurosurgery and Otolaryngology-Head; amp, Neck Surgery, The Affiliated Zhongnan Hospital of Wuhan University, Wuhan 430071, China; Qu, Xiangyang [Molecular Oncology Laboratory, Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, Illinois 60637, United States; Ministry of Education Key Laboratory of; Chen, Liqun [Molecular Oncology Laboratory, Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, Illinois 60637, United States; Ministry of Education Key Laboratory of; Yu, Xinyi [Molecular Oncology Laboratory, Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, Illinois 60637, United States; Ministry of Education Key Laboratory of; Zhang, Zhicai [Molecular Oncology Laboratory, Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, Illinois 60637, United States; Department; amp, Technology, Wuhan 430022, China; Zhao, Chen [Molecular Oncology Laboratory, Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, Illinois 60637, United States; Ministry of Education Key Laboratory of; Zeng, Zongyue [Molecular Oncology Laboratory, Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, Illinois 60637, United States; Ministry of Education Key Laboratory of; Zhang, Ruyi [Molecular Oncology Laboratory, Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, Illinois 60637, United States; Ministry of Education Key Laboratory of; Yan, Shujuan [Molecular Oncology Laboratory, Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, Illinois 60637, United States; Ministry of Education Key Laboratory of; Wu, Tingting [Molecular Oncology Laboratory, Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, Illinois 60637, United States; Departments of Neurosurgery and Otolaryngology-Head; amp, Neck Surgery, The Affiliated Zhongnan Hospital of Wuhan University, Wuhan 430071, China; Wu, Xingye [Molecular Oncology Laboratory, Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, Illinois 60637, United States; Ministry of Education Key Laboratory of; Shu, Yi [Molecular Oncology Laboratory, Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, Illinois 60637, United States; Ministry of Education Key Laboratory of; Li, Yasha [Molecular Oncology Laboratory, Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, Illinois 60637, United States; Ministry of Education Key Laboratory of; Zhang, Wenwen [Molecular Oncology Laboratory, Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, Illinois 60637, United States; Department; Reid, Russell R. [Molecular Oncology Laboratory, Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, Illinois 60637, United States; Department of Surgery, Section of Plastic; Lee, Michael J. [Molecular Oncology Laboratory, Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, Illinois 60637, United States; Wolf, Jennifer Moritis [Molecular Oncology Laboratory, Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, Illinois 60637, United States; Tirrell, Matthew [Institute for Molecular Engineering, The University of Chicago, Chicago, Illinois 60637, United States; Argonne National Laboratory, Argonne, Illinois 60439, United States; He, Tong-Chuan [Molecular Oncology Laboratory, Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, Illinois 60637, United States; Ministry of Education Key Laboratory of; de Pablo, Juan J. [Institute for Molecular Engineering, The University of Chicago, Chicago, Illinois 60637, United States; Argonne National Laboratory, Argonne, Illinois 60439, United States; Deng, Zhong-Liang [Department of Orthopaedic

2017-05-04

Graphene-based materials are used in many fields but have found only limited applications in biomedicine, including bone tissue engineering. Here, we demonstrate that novel hybrid materials consisting of gelatin-derived graphene and silicate nanosheets of Laponite (GL) are biocompatible and promote osteogenic differentiation of mesenchymal stem cells (MSCs). Homogeneous cell attachment, long-term proliferation, and osteogenic differentiation of MSCs on a GL-scaffold were confirmed using optical microscopy and scanning electron microscopy. GL-powders made by pulverizing the GL-scaffold were shown to promote bone morphogenetic protein (BMP9)-induced osteogenic differentiation. GL-powders increased the alkaline phosphatase (ALP) activity in immortalized mouse embryonic fibroblasts but decreased the ALP activity in more-differentiated immortalized mouse adipose-derived cells. Note, however, that GL-powders promoted BMP9-induced calcium mineral deposits in both MSC lines, as assessed using qualitative and quantitative alizarin red assays. Furthermore, the expression of chondro-osteogenic regulator markers such as Runx2, Sox9, osteopontin, and osteocalcin was upregulated by the GL-powder, independent of BMP9 stimulation; although the powder synergistically upregulated the BMP9-induced Osterix expression, the adipogenic marker PPAR gamma was unaffected. Furthermore, in vivo stem cell implantation experiments demonstrated that GL-powder could significantly enhance the BMP9-induced ectopic bone formation from MSCs. Collectively, our results strongly suggest that the GL hybrid materials promote BMP9-induced osteogenic differentiation of MSCs and hold promise for the development of bone tissue engineering platforms.

Hoxa5 Promotes Adipose Differentiation via Increasing DNA Methylation Level and Inhibiting PKA/HSL Signal Pathway in Mice

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Weina Cao

2018-02-01

Full Text Available Background/Aims: Impaired adipogenesis may be the underlying cause in the development of obesity and type II diabetes. Mechanistically, the family of Homeobox transcription factors is implicated in the regulation of adipocyte fate. Hoxa5 is highly expressed in adipocytes, and its mRNA expression is decreased during differentiation. However, the function of Hoxa5 in adipose tissue has been poorly understood. The aim of this study is to unveil the role of Hoxa5 on adipocyte differentiation and its underlying mechanisms. Methods: Quantitative real-time PCR (qPCR and western blot were performed to determine Hoxa5 expression in primary adipocytes and in adipose tissues from mice. Lipid accumulation was evaluated by bodipy staining. Dual luciferase assay was applied to explore the transcription factor of Hoxa5 and the transcriptional target gene modulated by Hoxa5. All measurements were performed at least for three times at least. Results: A significant reduction of Hoxa5 expression was observed in adipose tissue of High Fat Diet (HFD induced obesity mice. We determined Hoxa5 increased adipocytes differentiation and mitochondrial biogenesis in adipocytes in vitro. CEBPβ was determined a transcription factor of Hoxa5 and inhibited methylation level of Hoxa5 by combining on the promoter of Hoxa5. Importantly, we found Fabp4, a known positive regulator of adipocytes differentiation, was transcriptional activation by Hoxa5. In addition, Hoxa5 promotes adipocytes differentiation by inhibiting PKA/HSL pathway. Conclusion: Our study demonstrated the promoting role of Hoxa5 in adipocytes differentiation and therefore bringing a new therapeutic mean to the treatment of obesity and type II diabetes.

Sonochemical synthesis of fructose 1,6-bisphosphate dicalcium porous microspheres and their application in promotion of osteogenic differentiation.

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Qi, Chao; Zhou, Ding; Zhu, Ying-Jie; Sun, Tuan-Wei; Chen, Feng; Zhang, Chang-Qing

2017-08-01

Human bone mesenchymal stem cells (hBMSCs) have the ability to differentiate into bone and cartilage for clinical bone regeneration. Biomaterials with an innate ability to stimulate osteogenic differentiation of hBMSCs into bone and cartilage are considered attractive candidates for the applications in bone tissue engineering and regeneration. In this paper, we synthesized fructose 1,6-bisphosphate dicalcium (Ca 2 FBP) porous microspheres by the sonochemical method, and investigated the ability of Ca 2 FBP for the promotion of the osteogenic differentiation of hBMSCs. After the hBMSCs were co-cultured with the sterilized powder of Ca 2 FBP porous microspheres for different times, the cell proliferation assay, alkaline phosphatase activity assay, quantitative real-time polymerase chain reaction and western blotting were performed to investigate the bioactivity and osteogenic differentiation performance of the as-prepared product. Compared with hydroxyapatite nanorods, Ca 2 FBP porous microspheres show a superior bioactivity and osteoinductive potential, and can promote the cell differentiation of hBMSCs in vitro, thus, they are promising for applications in the tissue engineering field such as dental and bone defect repair. Copyright © 2017 Elsevier B.V. All rights reserved.

Leptin promotes osteoblast differentiation and mineralization of primary cultures of vascular smooth muscle cells by inhibiting glycogen synthase kinase (GSK)-3{beta}

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Zeadin, Melec G.; Butcher, Martin K.; Shaughnessy, Stephen G. [Department of Medicine, McMaster University, Hamilton, ON (Canada); Thrombosis and Atherosclerosis Research Institute, Hamilton, ON (Canada); Werstuck, Geoff H., E-mail: Geoff.Werstuck@taari.ca [Department of Medicine, McMaster University, Hamilton, ON (Canada); Thrombosis and Atherosclerosis Research Institute, Hamilton, ON (Canada)

2012-09-07

Highlights: Black-Right-Pointing-Pointer Leptin promotes osteoblast differentiation of primary smooth muscle cells. Black-Right-Pointing-Pointer Leptin regulates the expression of genes involved in osteoblast differentiation. Black-Right-Pointing-Pointer Constitutively active GSK-3{beta} attenuates leptin-induced osteoblast differentiation. Black-Right-Pointing-Pointer This suggests that leptin signals through GSK-3{beta} to promote osteoblast differentiation. -- Abstract: In this study, we begin to investigate the underlying mechanism of leptin-induced vascular calcification. We found that treatment of cultured bovine aortic smooth muscle cells (BASMCs) with leptin (0.5-4 {mu}g/ml) induced osteoblast differentiation in a dose-dependent manner. Furthermore, we found that leptin significantly increased the mRNA expression of osteopontin and bone sialoprotein, while down-regulating matrix gla protein (MGP) expression in BASMCs. Key factors implicated in osteoblast differentiation, including members of the Wnt signaling pathway, were examined. Exposure to leptin enhanced phosphorylation of GSK-3{beta} on serine-9 thereby inhibiting activity and promoting the nuclear accumulation of {beta}-catenin. Transfection of BASMCs with an adenovirus that expressed constitutively active GSK-3{beta} (Ad-GSK-3{beta} S9A) resulted in a >2-fold increase in GSK-3{beta} activity and a significant decrease in leptin-induced alkaline phosphatase (ALP) activity. In addition, qRT-PCR analysis showed that GSK-3{beta} activation resulted in a significant decrease in the expression of osteopontin and bone sialoprotein, but a marked increase in MGP mRNA expression. When taken together, our results suggest a mechanism by which leptin promotes osteoblast differentiation and vascular calcification in vivo.

Quercetin promotes proliferation and differentiation of oligodendrocyte precursor cells after oxygen/glucose deprivation-induced injury.

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Wu, Xiuxiang; Qu, Xuebin; Zhang, Qiang; Dong, Fuxing; Yu, Hongli; Yan, Chen; Qi, Dashi; Wang, Meng; Liu, Xuan; Yao, Ruiqin

2014-04-01

The aim of this study was to investigate quercetin's (Qu) ability to promote proliferation and differentiation of oligodendrocyte precursor cells (OPCs) under oxygen/glucose deprivation (OGD)-induced injury in vitro. The results showed that after OGD, OPCs survival rate was significantly increased by Qu as measured by Cell Counting Kit-8. Furthermore, Qu treatment reduced apoptosis of OPCs surveyed by Hoechst 33258 nuclear staining. Qu at 9 and 27 μM promoted the proliferation of OPCs the most by Brdu and Olig2 immunocytochemical staining after OGD 3 days. Also, Qu treatment for 8 days after OGD, the differentiation of OPCs to oligodendrocyte was detected by immunofluorescence staining showing that O4, Olig2, and myelin basic protein (MBP) positive cells were significantly increased compared to control group. Additionally, the protein levels of Olig2 and MBP of OPCs were quantified using western blot and mRNA levels of Olig2 and Inhibitor of DNA binding 2 (Id2) were measured by RT-PCR. Western blot showed a significant increase in Olig2 and MBP expression levels compared with controls after OGD and Qu treatment with a linear does-response curve from 3 to 81 μM. After treatment with Qu compared to its control group, Olig2 mRNA level was significantly up-regulated, whereas Id2 mRNA level was down-regulated. In conclusion, Qu at 3-27 μM can promote the proliferation and differentiation of OPCs after OGD injury and may regulate the activity of Olig2 and Id2.

NLS-RARα promotes proliferation and inhibits differentiation in HL-60 cells.

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Hu, Xiu-Xiu; Zhong, Liang; Zhang, Xi; Gao, Yuan-Mei; Liu, Bei-Zhong

2014-01-01

A unique mRNA produced in leukemic cells from a t(15;17) acute promyelocytic leukemia (APL) patient encodes a fusion protein between the retinoic acid receptor α (RARα) and a myeloid gene product called PML. Studies have reported that neutrophil elastase (NE) cleaves bcr-1-derived PML-RARα in early myeloid cells, leaving only the nuclear localization signal (NLS) of PML attached to RARα. The resultant NLS-RARα fusion protein mainly localizes to, and functions within, the cell nucleus. It is speculated that NLS-RARα may act in different ways from the wild-type RARα, but its biological characteristics have not been reported. This study takes two approaches. Firstly, the NLS-RARα was silenced with pNLS-RARα-shRNA. The mRNA and protein expression of NLS-RARα were detected by RT-PCR and Western blot respectively. Cell proliferation in vitro was assessed by MTT assay. Flow cytometry (FCM) was used to detect the differentiation of cells. Secondly, the NLS-RARα was over-expressed by preparation of recombinant adenovirus HL-60/pAd-NLS-RARα. The assays of mRNA and protein expression of NLS-RARα, and cell proliferation, were as above. By contrast, cell differentiation was stimulated by all trans retinoic acid (ATRA) (2.5µmol/L) at 24h after virus infection of pAd-NLS-RARα, and then detected by CD11b labeling two days later. The transcription and translation of C-MYC was detected in HL-60/pAd-NLS-RARα cells which treated by ATRA. Our results showed that compared to the control groups, the expression of NLS-RARα was significantly reduced in the HL-60/pNLS-RARα-shRNA cells, and increased dramatically in the HL-60/pAd-NLS-RARα cells. The proliferation was remarkably inhibited in the HL-60/pNLS-RARα-shRNA cells in a time-dependent manner, but markedly promoted in the HL-60/pAd-NLS-RARα cells. FCM outcome revealed the differentiation increased in HL-60/pNLS-RARα-shRNA cells, and decreased in the HL-60/pAd-NLS-RARα cells treated with 2.5µmol/L ATRA. The

The Tocotrienol-Rich Fraction Is Superior to Tocopherol in Promoting Myogenic Differentiation in the Prevention of Replicative Senescence of Myoblasts.

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Shy Cian Khor

Full Text Available Aging results in a loss of muscle mass and strength. Myoblasts play an important role in maintaining muscle mass through regenerative processes, which are impaired during aging. Vitamin E potentially ameliorates age-related phenotypes. Hence, this study aimed to determine the effects of the tocotrienol-rich fraction (TRF and α-tocopherol (ATF in protecting myoblasts from replicative senescence and promoting myogenic differentiation. Primary human myoblasts were cultured into young and senescent stages and were then treated with TRF or ATF for 24 h, followed by an analysis of cell proliferation, senescence biomarkers, cellular morphology and differentiation. Our data showed that replicative senescence impaired the normal regenerative processes of myoblasts, resulting in changes in cellular morphology, cell proliferation, senescence-associated β-galactosidase (SA-β-gal expression, myogenic differentiation and myogenic regulatory factors (MRFs expression. Treatment with both TRF and ATF was beneficial to senescent myoblasts in reclaiming the morphology of young cells, improved cell viability and decreased SA-β-gal expression. However, only TRF treatment increased BrdU incorporation in senescent myoblasts, as well as promoted myogenic differentiation through the modulation of MRFs at the mRNA and protein levels. MYOD1 and MYOG gene expression and myogenin protein expression were modulated in the early phases of myogenic differentiation. In conclusion, the tocotrienol-rich fraction is superior to α-tocopherol in ameliorating replicative senescence-related aberration and promoting differentiation via modulation of MRFs expression, indicating vitamin E potential in modulating replicative senescence of myoblasts.

Neural stem cells promote nerve regeneration through IL12-induced Schwann cell differentiation.

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Lee, Don-Ching; Chen, Jong-Hang; Hsu, Tai-Yu; Chang, Li-Hsun; Chang, Hsu; Chi, Ya-Hui; Chiu, Ing-Ming

2017-03-01

Regeneration of injured peripheral nerves is a slow, complicated process that could be improved by implantation of neural stem cells (NSCs) or nerve conduit. Implantation of NSCs along with conduits promotes the regeneration of damaged nerve, likely because (i) conduit supports and guides axonal growth from one nerve stump to the other, while preventing fibrous tissue ingrowth and retaining neurotrophic factors; and (ii) implanted NSCs differentiate into Schwann cells and maintain a growth factor enriched microenvironment, which promotes nerve regeneration. In this study, we identified IL12p80 (homodimer of IL12p40) in the cell extracts of implanted nerve conduit combined with NSCs by using protein antibody array and Western blotting. Levels of IL12p80 in these conduits are 1.6-fold higher than those in conduits without NSCs. In the sciatic nerve injury mouse model, implantation of NSCs combined with nerve conduit and IL12p80 improves motor recovery and increases the diameter up to 4.5-fold, at the medial site of the regenerated nerve. In vitro study further revealed that IL12p80 stimulates the Schwann cell differentiation of mouse NSCs through the phosphorylation of signal transducer and activator of transcription 3 (Stat3). These results suggest that IL12p80 can trigger Schwann cell differentiation of mouse NSCs through Stat3 phosphorylation and enhance the functional recovery and the diameter of regenerated nerves in a mouse sciatic nerve injury model. Copyright © 2016 Elsevier Inc. All rights reserved.

Differential Radiosensitizing Effect of Valproic Acid in Differentiation Versus Self-Renewal Promoting Culture Conditions

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Debeb, Bisrat G.; Xu Wei; Mok, Henry; Li Li; Robertson, Fredika; Ueno, Naoto T.; Reuben, Jim; Lucci, Anthony; Cristofanilli, Massimo; Woodward, Wendy A.

2010-01-01

Purpose: It has been shown that valproic acid (VA) enhances the proliferation and self-renewal of normal hematopoietic stem cells and that breast cancer stem/progenitor cells can be resistant to radiation. From these data, we hypothesized that VA would fail to radiosensitize breast cancer stem/progenitor cells grown to three-dimensional (3D) mammospheres. Methods and Materials: We used the MCF7 breast cancer cell line grown under stem cell-promoting culture conditions (3D mammosphere) and standard nonstem cell monolayer culture conditions (two-dimensional) to examine the effect of pretreatment with VA on radiation sensitivity in clonogenic survival assays and on the expression of embryonic stem cell transcription factors. Results: 3D-cultured MCF-7 cells expressed higher levels of Oct4, Nanog, and Sox2. The 3D passage enriched self-renewal and increased radioresistance in the 3D mammosphere formation assays. VA radiosensitized adherent cells but radioprotected 3D cells in single-fraction clonogenic assays. Moreover, fractionated radiation sensitized VA-treated adherent MCF7 cells but did not have a significant effect on VA-treated single cells grown to mammospheres. Conclusion: We have concluded that VA might preferentially radiosensitize differentiated cells compared with those expressing stem cell surrogates and that stem cell-promoting culture is a useful tool for in vitro evaluation of novel cancer therapeutic agents and radiosensitizers.

Human CD68 promoter GFP transgenic mice allow analysis of monocyte to macrophage differentiation in vivo.

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Iqbal, Asif J; McNeill, Eileen; Kapellos, Theodore S; Regan-Komito, Daniel; Norman, Sophie; Burd, Sarah; Smart, Nicola; Machemer, Daniel E W; Stylianou, Elena; McShane, Helen; Channon, Keith M; Chawla, Ajay; Greaves, David R

2014-10-09

The recruitment of monocytes and their differentiation into macrophages at sites of inflammation are key events in determining the outcome of the inflammatory response and initiating the return to tissue homeostasis. To study monocyte trafficking and macrophage differentiation in vivo, we have generated a novel transgenic reporter mouse expressing a green fluorescent protein (GFP) under the control of the human CD68 promoter. CD68-GFP mice express high levels of GFP in both monocyte and embryo-derived tissue resident macrophages in adult animals. The human CD68 promoter drives GFP expression in all CD115(+) monocytes of adult blood, spleen, and bone marrow; we took advantage of this to directly compare the trafficking of bone marrow-derived CD68-GFP monocytes to that of CX3CR1(GFP) monocytes in vivo using a sterile zymosan peritonitis model. Unlike CX3CR1(GFP) monocytes, which downregulate GFP expression on differentiation into macrophages in this model, CD68-GFP monocytes retain high-level GFP expression for 72 hours after differentiation into macrophages, allowing continued cell tracking during resolution of inflammation. In summary, this novel CD68-GFP transgenic reporter mouse line represents a powerful resource for analyzing monocyte mobilization and monocyte trafficking as well as studying the fate of recruited monocytes in models of acute and chronic inflammation. © 2014 by The American Society of Hematology.

Paracrine and autocrine signals promoting full chondrogenic differentiation of a mesoblastic cell line.

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Locker, Morgane; Kellermann, Odile; Boucquey, Marie; Khun, Huot; Huerre, Michel; Poliard, Anne

2004-01-01

The pluripotent mesoblastic C1 cell line was used under serum-free culture conditions to investigate how paracrine and autocrine signals cooperate to drive chondrogenesis. Sequential addition of two systemic hormones, dexamethasone and triiodothyronine, permits full chondrogenic differentiation. The cell intrinsic activation of the BMP signaling pathway and Sox9 expression occurring on mesoblastic condensation is insufficient for recruitment of the progenitors. Dexamethasone-dependent Sox9 upregulation is essential for chondrogenesis. Differentiation of lineage stem cells relies on cell autonomous regulations modulated by external signals. We used the pluripotent mesoblastic C1 cell line under serum-free culture conditions to investigate how paracrine and autocrine signals cooperate to induce differentiation of a precursor clone along the chondrogenic lineage. C1 cells, cultured as aggregates, were induced toward chondrogenesis by addition of 10(-7) M dexamethasone in serum-free medium. After 30 days, dexamethasone was replaced by 10 nM triiodothyronine to promote final hypertrophic conversion. Mature and hypertrophic phenotypes were characterized by immunocytochemistry using specific antibodies against types II and X collagens, respectively. Type II collagen, bone morphogenetic proteins (BMPs), BMP receptors, Smads, and Sox9 expression were monitored by reverse transcriptase-polymerase chain reaction (RT-PCR), Northern blot, and/or Western blot analysis. Once C1 cells have formed nodules, sequential addition of two systemic hormones is sufficient to promote full chondrogenic differentiation. In response to dexamethasone, nearly 100% of the C1 precursors engage in chondrogenesis and convert within 30 days into mature chondrocytes, which triggers a typical cartilage matrix. On day 25, a switch in type II procollagen mRNA splicing acted as a limiting step in the acquisition of the mature chondrocyte phenotype. On day 30, substitution of dexamethasone with

Gold nanoparticles promote osteogenic differentiation in human adipose-derived mesenchymal stem cells through the Wnt/β-catenin signaling pathway

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Choi SY

2015-07-01

Full Text Available Seon Young Choi,1 Min Seok Song,1 Pan Dong Ryu,1 Anh Thu Ngoc Lam,2 Sang-Woo Joo,2 So Yeong Lee1 1Laboratory of Veterinary Pharmacology, Research Institute for Veterinary Science, College of Veterinary Medicine, Seoul National University, 2Department of Chemistry, Soongsil University, Seoul, South Korea Abstract: Gold nanoparticles (AuNPs are attractive materials for use in biomedicine due to their physical properties. Increasing evidence suggests that several nanoparticles induce the differentiation of human mesenchymal stem cells into osteoblasts and adipocytes. In this study, we hypothesized that chitosan-conjugated AuNPs promote the osteogenic differentiation of human adipose-derived mesenchymal stem cells. For the evaluation of osteogenic differentiation, alizarin red staining, an alamarBlue® assay, and a quantitative real-time polymerase chain reaction analysis were performed. In order to examine specific signaling pathways, immunofluorescence and a western blotting assay were performed. Our results demonstrate that chitosan-conjugated AuNPs increase the deposition of calcium content and the expression of marker genes related to osteogenic differentiation in human adipose-derived mesenchymal stem cells at nontoxic concentrations. These results indicate that chitosan-conjugated AuNPs promote osteogenesis through the Wnt/β-catenin signaling pathway. Therefore, chitosan-conjugated AuNPs can be used as a reagent for promoting bone formation. Keywords: chitosan-conjugated gold nanoparticle, mineralization, nonphosphorylated beta-catenin

Vaccine adjuvant MF59 promotes the intranodal differentiation of antigen-loaded and activated monocyte-derived dendritic cells.

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Rossella Cioncada

Full Text Available MF59 is an oil-in-water emulsion adjuvant approved for human influenza vaccination in European Union. The mode of action of MF59 is not fully elucidated yet, but results from several years of investigation indicate that MF59 establishes an immunocompetent environment at injection site which promotes recruitment of immune cells, including antigen presenting cells (APCs, that are facilitated to engulf antigen and transport it to draining lymph node (dLN where the antigen is accumulated. In vitro studies showed that MF59 promotes the differentiation of monocytes to dendritic cells (Mo-DCs. Since after immunization with MF59, monocytes are rapidly recruited both at the injection site and in dLN and appear to have a morphological change toward a DC-like phenotype, we asked whether MF59 could play a role in inducing differentiation of Mo-DC in vivo. To address this question we immunized mice with the auto-fluorescent protein Phycoerythrin (PE as model antigen, in presence or absence of MF59. We measured the APC phenotype and their antigen uptake within dLNs, the antigen distribution within the dLN compartments and the humoral response to PE. In addition, using Ovalbumin as model antigen, we measured the capacity of dLN APCs to induce antigen-specific CD4 T cell proliferation. Here, we show, for the first time, that MF59 promotes differentiation of Mo-DCs within dLNs from intranodal recruited monocytes and we suggest that this differentiation could take place in the medullary compartment of the LN. In addition we show that the Mo-DC subset represents the major source of antigen-loaded and activated APCs within the dLN when immunizing with MF59. Interestingly, this finding correlates with the enhanced triggering of antigen-specific CD4 T cell response induced by LN APCs. This study therefore demonstrates that MF59 is able to promote an immunocompetent environment also directly within the dLN, offering a novel insight on the mechanism of action of

Omega 3 fatty acids reduce myeloid progenitor cell frequency in the bone marrow of mice and promote progenitor cell differentiation

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Sollars Vincent E

2009-03-01

Full Text Available Abstract Background Omega 3 fatty acids have been found to inhibit proliferation, induce apoptosis, and promote differentiation in various cell types. The processes of cell survival, expansion, and differentiation are of key importance in the regulation of hematopoiesis. We investigated the role of omega 3 fatty acids in controlling the frequency of various myeloid progenitor cells in the bone marrow of mice. Increased progenitor cell frequency and blocked differentiation are characteristics of hematopoietic disorders of the myeloid lineage, such as myeloproliferative diseases and myeloid leukemias. Results We found that increasing the proportion of omega 3 fatty acids relative to the proportion of omega 6 fatty acids in the diet caused increased differentiation and reduced the frequency of myeloid progenitor cells in the bone marrow of mice. Furthermore, this had no adverse effect on peripheral white blood cell counts. Conclusion Our results indicate that omega 3 fatty acids impact hematopoietic differentiation by reducing myeloid progenitor cell frequency in the bone marrow and promoting progenitor cell differentiation. Further exploration of this discovery could lead to the use of omega 3 fatty acids as a therapeutic option for patients that have various disorders of hematopoiesis.

Gold Nanoparticles Promote Proliferation of Human Periodontal Ligament Stem Cells and Have Limited Effects on Cells Differentiation

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Chen Li

2016-01-01

Full Text Available Gold nanoparticles (AuNPs had been widely applied in the practice and advancement of chemistry, biology, and medicine due to facility of synthesis and versatility in surface functionalization. Recent studies had shown that AuNPs can be applied to cells, affecting cellular physiological processes such as proliferation and differentiation. In this study, four diameters of AuNPs (20, 40, 60, and 80 nm were cocultured with human periodontal ligament cells (hPDLCs at six different concentrations. The optimal size and concentration of AuNPs were selected to treat human periodontal ligament stem cells (hPDLSCs to evaluate proliferation. Moreover, the influence of AuNPs on multiple differentiation capacity of hPDLSCs was clarified. The results revealed that AuNPs (60 nm, 56 μM can effectively promote the proliferation of hPDLCs/hPDLSCs in vitro, slightly enhance osteoblastic differentiation, and have no effect on adipogenic differentiation. In addition, the expression of COL-1, Runx2, BSP, and OCN was upregulated in the presence of AuNPs (60 nm, 56 μM. These results indicated that AuNPs (60 nm, 56 μM can effectively promote the proliferation of hPDLCs/hPDLSCs and have no significant effect on the differentiation of hPDLSCs. These results provide an insight on the advantage of implementing of AuNPs on hPDLSCs culture and expose the influence of these materials on periodontal tissue engineering.

Peroxisome proliferator-activated receptor β/δ (PPARβ/δ) activates promyogenic signaling pathways, thereby promoting myoblast differentiation

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Lee, Sang-Jin; Go, Ga-Yeon; Yoo, Miran; Kim, Yong Kee [Research Center for Cell Fate Control, College of Pharmacy, Sookmyung Women' s University, Seoul 140-742 (Korea, Republic of); Seo, Dong-Wan [College of Pharmacy, Dankook University, Cheonan 330-714 (Korea, Republic of); Kang, Jong-Sun [Department of Molecular Cell Biology, Sungkyunkwan University School of Medicine, Samsung Biomedical Research Institute, Suwon 440-746 (Korea, Republic of); Bae, Gyu-Un, E-mail: gbae@sookmyung.ac.kr [Research Center for Cell Fate Control, College of Pharmacy, Sookmyung Women' s University, Seoul 140-742 (Korea, Republic of)

2016-01-29

Peroxisome proliferator-activated receptor β/δ (PPARβ/δ) regulates postnatal myogenesis by alleviating myostatin activity, but the molecular mechanisms by which it regulates myogenesis are not fully understood. In this study, we investigate molecular mechanisms of PPARβ/δ in myoblast differentiation. C2C12 myoblasts treated with a PPARβ/δ agonist, GW0742 exhibit enhanced myotube formation and muscle-specific gene expression. GW0742 treatment dramatically activates promyogenic kinases, p38MAPK and Akt, in a dose-dependent manner. GW0742-stimulated myoblast differentiation is mediated by p38MAPK and Akt, since it failed to restore myoblast differentiation repressed by inhibition of p38MAPK and Akt. In addition, GW0742 treatment enhances MyoD-reporter activities. Consistently, overexpression of PPARβ/δ enhances myoblast differentiation accompanied by elevated activation of p38MAPK and Akt. Collectively, these results suggest that PPARβ/δ enhances myoblast differentiation through activation of promyogenic signaling pathways. - Highlights: • A PPARβ/δ agonist, GW0742 promotes myoblast differentiation. • GW0742 activates both p38MAPK and Akt activation in myogenic differentiation. • GW0742 enhances MyoD activity for myogenic differentiation. • Overexpression of PPARβ/δ enhances myoblast differentiation via activating promyogenic signaling pathways. • This is the first finding for agonistic mechanism of PPARβ/δ in myogenesis.

Peroxisome proliferator-activated receptor β/δ (PPARβ/δ) activates promyogenic signaling pathways, thereby promoting myoblast differentiation

International Nuclear Information System (INIS)

Lee, Sang-Jin; Go, Ga-Yeon; Yoo, Miran; Kim, Yong Kee; Seo, Dong-Wan; Kang, Jong-Sun; Bae, Gyu-Un

2016-01-01

Peroxisome proliferator-activated receptor β/δ (PPARβ/δ) regulates postnatal myogenesis by alleviating myostatin activity, but the molecular mechanisms by which it regulates myogenesis are not fully understood. In this study, we investigate molecular mechanisms of PPARβ/δ in myoblast differentiation. C2C12 myoblasts treated with a PPARβ/δ agonist, GW0742 exhibit enhanced myotube formation and muscle-specific gene expression. GW0742 treatment dramatically activates promyogenic kinases, p38MAPK and Akt, in a dose-dependent manner. GW0742-stimulated myoblast differentiation is mediated by p38MAPK and Akt, since it failed to restore myoblast differentiation repressed by inhibition of p38MAPK and Akt. In addition, GW0742 treatment enhances MyoD-reporter activities. Consistently, overexpression of PPARβ/δ enhances myoblast differentiation accompanied by elevated activation of p38MAPK and Akt. Collectively, these results suggest that PPARβ/δ enhances myoblast differentiation through activation of promyogenic signaling pathways. - Highlights: • A PPARβ/δ agonist, GW0742 promotes myoblast differentiation. • GW0742 activates both p38MAPK and Akt activation in myogenic differentiation. • GW0742 enhances MyoD activity for myogenic differentiation. • Overexpression of PPARβ/δ enhances myoblast differentiation via activating promyogenic signaling pathways. • This is the first finding for agonistic mechanism of PPARβ/δ in myogenesis.

Dynamic 3D culture promotes spontaneous embryonic stem cell differentiation in vitro.

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Gerlach, Jörg C; Hout, Mariah; Edsbagge, Josefina; Björquist, Petter; Lübberstedt, Marc; Miki, Toshio; Stachelscheid, Harald; Schmelzer, Eva; Schatten, Gerald; Zeilinger, Katrin

2010-02-01

Spontaneous in vitro differentiation of mouse embryonic stem cells (mESC) is promoted by a dynamic, three-dimensional (3D), tissue-density perfusion technique with continuous medium perfusion and exchange in a novel four-compartment, interwoven capillary bioreactor. We compared ectodermal, endodermal, and mesodermal immunoreactive tissue structures formed by mESC at culture day 10 with mouse fetal tissue development at gestational day E9.5. The results show that the bioreactor cultures more closely resemble mouse fetal tissue development at gestational day E9.5 than control mESC cultured in Petri dishes.

FGF-2 signal promotes proliferation of cerebellar progenitor cells and their oligodendrocytic differentiation at early postnatal stage

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Naruse, Masae; Shibasaki, Koji; Ishizaki, Yasuki, E-mail: yasukiishizaki@gunma-u.ac.jp

2015-08-07

The origins and developmental regulation of cerebellar oligodendrocytes are largely unknown, although some hypotheses of embryonic origins have been suggested. Neural stem cells exist in the white matter of postnatal cerebellum, but it is unclear whether these neural stem cells generate oligodendrocytes at postnatal stages. We previously showed that cerebellar progenitor cells, including neural stem cells, widely express CD44 at around postnatal day 3. In the present study, we showed that CD44-positive cells prepared from the postnatal day 3 cerebellum gave rise to neurospheres, while CD44-negative cells prepared from the same cerebellum did not. These neurospheres differentiated mainly into oligodendrocytes and astrocytes, suggesting that CD44-positive neural stem/progenitor cells might generate oligodendrocytes in postnatal cerebellum. We cultured CD44-positive cells from the postnatal day 3 cerebellum in the presence of signaling molecules known as mitogens or inductive differentiation factors for oligodendrocyte progenitor cells. Of these, only FGF-2 promoted survival and proliferation of CD44-positive cells, and these cells differentiated into O4+ oligodendrocytes. Furthermore, we examined the effect of FGF-2 on cerebellar oligodendrocyte development ex vivo. FGF-2 enhanced proliferation of oligodendrocyte progenitor cells and increased the number of O4+ and CC1+ oligodendrocytes in slice cultures. These results suggest that CD44-positive cells might be a source of cerebellar oligodendrocytes and that FGF-2 plays important roles in their development at an early postnatal stage. - Highlights: • CD44 is expressed in cerebellar neural stem/progenitor cells at postnatal day 3 (P3). • FGF-2 promoted proliferation of CD44-positive progenitor cells from P3 cerebellum. • FGF-2 promoted oligodendrocytic differentiation of CD44-positive progenitor cells. • FGF-2 increased the number of oligodendrocytes in P3 cerebellar slice culture.

FGF-2 signal promotes proliferation of cerebellar progenitor cells and their oligodendrocytic differentiation at early postnatal stage

International Nuclear Information System (INIS)

Naruse, Masae; Shibasaki, Koji; Ishizaki, Yasuki

2015-01-01

The origins and developmental regulation of cerebellar oligodendrocytes are largely unknown, although some hypotheses of embryonic origins have been suggested. Neural stem cells exist in the white matter of postnatal cerebellum, but it is unclear whether these neural stem cells generate oligodendrocytes at postnatal stages. We previously showed that cerebellar progenitor cells, including neural stem cells, widely express CD44 at around postnatal day 3. In the present study, we showed that CD44-positive cells prepared from the postnatal day 3 cerebellum gave rise to neurospheres, while CD44-negative cells prepared from the same cerebellum did not. These neurospheres differentiated mainly into oligodendrocytes and astrocytes, suggesting that CD44-positive neural stem/progenitor cells might generate oligodendrocytes in postnatal cerebellum. We cultured CD44-positive cells from the postnatal day 3 cerebellum in the presence of signaling molecules known as mitogens or inductive differentiation factors for oligodendrocyte progenitor cells. Of these, only FGF-2 promoted survival and proliferation of CD44-positive cells, and these cells differentiated into O4+ oligodendrocytes. Furthermore, we examined the effect of FGF-2 on cerebellar oligodendrocyte development ex vivo. FGF-2 enhanced proliferation of oligodendrocyte progenitor cells and increased the number of O4+ and CC1+ oligodendrocytes in slice cultures. These results suggest that CD44-positive cells might be a source of cerebellar oligodendrocytes and that FGF-2 plays important roles in their development at an early postnatal stage. - Highlights: • CD44 is expressed in cerebellar neural stem/progenitor cells at postnatal day 3 (P3). • FGF-2 promoted proliferation of CD44-positive progenitor cells from P3 cerebellum. • FGF-2 promoted oligodendrocytic differentiation of CD44-positive progenitor cells. • FGF-2 increased the number of oligodendrocytes in P3 cerebellar slice culture

Rigid microenvironments promote cardiac differentiation of mouse and human embryonic stem cells

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Arshi, Armin; Nakashima, Yasuhiro; Nakano, Haruko; Eaimkhong, Sarayoot; Evseenko, Denis; Reed, Jason; Stieg, Adam Z.; Gimzewski, James K.; Nakano, Atsushi

2013-04-01

While adult heart muscle is the least regenerative of tissues, embryonic cardiomyocytes are proliferative, with embryonic stem (ES) cells providing an endless reservoir. In addition to secreted factors and cell-cell interactions, the extracellular microenvironment has been shown to play an important role in stem cell lineage specification, and understanding how scaffold elasticity influences cardiac differentiation is crucial to cardiac tissue engineering. Though previous studies have analyzed the role of matrix elasticity on the function of differentiated cardiomyocytes, whether it affects the induction of cardiomyocytes from pluripotent stem cells is poorly understood. Here, we examine the role of matrix rigidity on cardiac differentiation using mouse and human ES cells. Culture on polydimethylsiloxane (PDMS) substrates of varied monomer-to-crosslinker ratios revealed that rigid extracellular matrices promote a higher yield of de novo cardiomyocytes from undifferentiated ES cells. Using a genetically modified ES system that allows us to purify differentiated cardiomyocytes by drug selection, we demonstrate that rigid environments induce higher cardiac troponin T expression, beating rate of foci, and expression ratio of adult α- to fetal β- myosin heavy chain in a purified cardiac population. M-mode and mechanical interferometry image analyses demonstrate that these ES-derived cardiomyocytes display functional maturity and synchronization of beating when co-cultured with neonatal cardiomyocytes harvested from a developing embryo. Together, these data identify matrix stiffness as an independent factor that instructs not only the maturation of already differentiated cardiomyocytes but also the induction and proliferation of cardiomyocytes from undifferentiated progenitors. Manipulation of the stiffness will help direct the production of functional cardiomyocytes en masse from stem cells for regenerative medicine purposes.

Inhibition of Sirt1 promotes neural progenitors toward motoneuron differentiation from human embryonic stem cells

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Zhang, Yun; Wang, Jing [Department of Neurology, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing 100191 (China); Clinical Stem Cell Center, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing 100191 (China); Chen, Guian [Clinical Stem Cell Center, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing 100191 (China); Reproductive Medical Center, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing 100191 (China); Fan, Dongsheng, E-mail: dsfan@yahoo.cn [Department of Neurology, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing 100191 (China); Clinical Stem Cell Center, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing 100191 (China); Deng, Min, E-mail: dengmin1706@yahoo.com.cn [Department of Neurology, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing 100191 (China); Clinical Stem Cell Center, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing 100191 (China)

2011-01-14

Research highlights: {yields} Nicotinamide inhibit Sirt1. {yields} MASH1 and Ngn2 activation. {yields} Increase the expression of HB9. {yields} Motoneurons formation increases significantly. -- Abstract: Several protocols direct human embryonic stem cells (hESCs) toward differentiation into functional motoneurons, but the efficiency of motoneuron generation varies based on the human ESC line used. We aimed to develop a novel protocol to increase the formation of motoneurons from human ESCs. In this study, we tested a nuclear histone deacetylase protein, Sirt1, to promote neural precursor cell (NPC) development during differentiation of human ESCs into motoneurons. A specific inhibitor of Sirt1, nicotinamide, dramatically increased motoneuron formation. We found that about 60% of the cells from the total NPCs expressed HB9 and {beta}III-tubulin, commonly used motoneuronal markers found in neurons derived from ESCs following nicotinamide treatment. Motoneurons derived from ESC expressed choline acetyltransferase (ChAT), a positive marker of mature motoneuron. Moreover, we also examined the transcript levels of Mash1, Ngn2, and HB9 mRNA in the differentiated NPCs treated with the Sirt1 activator resveratrol (50 {mu}M) or inhibitor nicotinamide (100 {mu}M). The levels of Mash1, Ngn2, and HB9 mRNA were significantly increased after nicotinamide treatment compared with control groups, which used the traditional protocol. These results suggested that increasing Mash1 and Ngn2 levels by inhibiting Sirt1 could elevate HB9 expression, which promotes motoneuron differentiation. This study provides an alternative method for the production of transplantable motoneurons, a key requirement in the development of hESC-based cell therapy in motoneuron disease.

Inhibition of Sirt1 promotes neural progenitors toward motoneuron differentiation from human embryonic stem cells

International Nuclear Information System (INIS)

Zhang, Yun; Wang, Jing; Chen, Guian; Fan, Dongsheng; Deng, Min

2011-01-01

Research highlights: → Nicotinamide inhibit Sirt1. → MASH1 and Ngn2 activation. → Increase the expression of HB9. → Motoneurons formation increases significantly. -- Abstract: Several protocols direct human embryonic stem cells (hESCs) toward differentiation into functional motoneurons, but the efficiency of motoneuron generation varies based on the human ESC line used. We aimed to develop a novel protocol to increase the formation of motoneurons from human ESCs. In this study, we tested a nuclear histone deacetylase protein, Sirt1, to promote neural precursor cell (NPC) development during differentiation of human ESCs into motoneurons. A specific inhibitor of Sirt1, nicotinamide, dramatically increased motoneuron formation. We found that about 60% of the cells from the total NPCs expressed HB9 and βIII-tubulin, commonly used motoneuronal markers found in neurons derived from ESCs following nicotinamide treatment. Motoneurons derived from ESC expressed choline acetyltransferase (ChAT), a positive marker of mature motoneuron. Moreover, we also examined the transcript levels of Mash1, Ngn2, and HB9 mRNA in the differentiated NPCs treated with the Sirt1 activator resveratrol (50 μM) or inhibitor nicotinamide (100 μM). The levels of Mash1, Ngn2, and HB9 mRNA were significantly increased after nicotinamide treatment compared with control groups, which used the traditional protocol. These results suggested that increasing Mash1 and Ngn2 levels by inhibiting Sirt1 could elevate HB9 expression, which promotes motoneuron differentiation. This study provides an alternative method for the production of transplantable motoneurons, a key requirement in the development of hESC-based cell therapy in motoneuron disease.

Electrical stimulation promotes nerve cell differentiation on polypyrrole/poly (2-methoxy-5 aniline sulfonic acid) composites.

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Liu, Xiao; Gilmore, Kerry J; Moulton, Simon E; Wallace, Gordon G

2009-12-01

The purpose of this work was to investigate for the first time the potential biomedical applications of novel polypyrrole (PPy) composites incorporating a large polyelectrolyte dopant, poly (2-methoxy-5 aniline sulfonic acid) (PMAS). The physical and electrochemical properties were characterized. The PPy/PMAS composites were found to be smooth and hydrophilic and have low electrical impedance. We demonstrate that PPy/PMAS supports nerve cell (PC12) differentiation, and that clinically relevant 250 Hz biphasic current pulses delivered via PPy/PMAS films significantly promote nerve cell differentiation in the presence of nerve growth factor (NGF). The capacity of PPy/PMAS composites to support and enhance nerve cell differentiation via electrical stimulation renders them valuable for medical implants for neurological applications.

The hidden winners of renewable energy promotion: Insights into sector-specific wage differentials

International Nuclear Information System (INIS)

Antoni, Manfred; Janser, Markus; Lehmer, Florian

2015-01-01

In light of Germany's energy system transformation, this paper examines differences in employment structures and wage differentials between renewable energy establishments and their sector peers. To do so, we have developed a novel data set by linking company-level information from the German Renewable Energy Federation with administrative establishment-level data from the Institute for Employment Research. Descriptive evidence shows significant differences in wages and several other characteristics between renewable energy establishments and their sector peers. Our estimates give evidence that human capital and other establishment-level characteristics mostly explain the wage differential among manufacturers and energy providers. However, we find a persistent ‘renewable energy wage premium' of more than ten percent in construction/installation activities and architectural/engineering services. We interpret this premium as a positive indirect effect of the promotion of renewable energies for the benefit of employees in renewable energy establishments within these two sectors. - Highlights: • Renewable energy (RE) firms pay considerably more than their non-RE sector peers. • In manufacturing and energy supply, firm attributes explain mainly the wage gap. • In installation, planning and project management one third remains unexplained. • This unexplained rest represents a ‘RE wage premium’ of around 10 percent. • The employees in both sectors are the ‘hidden winners’ of RE promotion.

Gelatin-Based Hydrogels Promote Chondrogenic Differentiation of Human Adipose Tissue-Derived Mesenchymal Stem Cells In Vitro

Science.gov (United States)

Salamon, Achim; van Vlierberghe, Sandra; van Nieuwenhove, Ine; Baudisch, Frank; Graulus, Geert-Jan; Benecke, Verena; Alberti, Kristin; Neumann, Hans-Georg; Rychly, Joachim; Martins, José C.; Dubruel, Peter; Peters, Kirsten

2014-01-01

Due to the weak regeneration potential of cartilage, there is a high clinical incidence of articular joint disease, leading to a strong demand for cartilaginous tissue surrogates. The aim of this study was to evaluate a gelatin-based hydrogel for its suitability to support chondrogenic differentiation of human mesenchymal stem cells. Gelatin-based hydrogels are biodegradable, show high biocompatibility, and offer possibilities to introduce functional groups and/or ligands. In order to prove their chondrogenesis-supporting potential, a hydrogel film was developed and compared with standard cell culture polystyrene regarding the differentiation behavior of human mesenchymal stem cells. Cellular basis for this study were human adipose tissue-derived mesenchymal stem cells, which exhibit differentiation potential along the adipogenic, osteogenic and chondrogenic lineage. The results obtained show a promotive effect of gelatin-based hydrogels on chondrogenic differentiation of mesenchymal stem cells in vitro and therefore encourage subsequent in vivo studies. PMID:28788517

Dual reporter transgene driven by 2.3Col1a1 promoter is active in differentiated osteoblasts

Science.gov (United States)

Marijanovic, Inga; Jiang, Xi; Kronenberg, Mark S.; Stover, Mary Louise; Erceg, Ivana; Lichtler, Alexander C.; Rowe, David W.

2003-01-01

AIM: As quantitative and spatial analyses of promoter reporter constructs are not easily performed in intact bone, we designed a reporter gene specific to bone, which could be analyzed both visually and quantitatively by using chloramphenicol acetyltransferase (CAT) and a cyan version of green fluorescent protein (GFPcyan), driven by a 2.3-kb fragment of the rat collagen promoter (Col2.3). METHODS: The construct Col2.3CATiresGFPcyan was used for generating transgenic mice. Quantitative measurement of promoter activity was performed by CAT analysis of different tissues derived from transgenic animals; localization was performed by visualized GFP in frozen bone sections. To assess transgene expression during in vitro differentiation, marrow stromal cell and neonatal calvarial osteoblast cultures were analyzed for CAT and GFP activity. RESULTS: In mice, CAT activity was detected in the calvaria, long bone, teeth, and tendon, whereas histology showed that GFP expression was limited to osteoblasts and osteocytes. In cell culture, increased activity of CAT correlated with increased differentiation, and GFP activity was restricted to mineralized nodules. CONCLUSION: The concept of a dual reporter allows a simultaneous visual and quantitative analysis of transgene activity in bone.

Cholera Toxin Promotes Th17 Cell Differentiation by Modulating Expression of Polarizing Cytokines and the Antigen-Presenting Potential of Dendritic Cells.

Science.gov (United States)

Kang, Jung-Ok; Lee, Jee-Boong; Chang, Jun

2016-01-01

Cholera toxin (CT), an exotoxin produced by Vibrio cholera, acts as a mucosal adjuvant. In a previous study, we showed that CT skews differentiation of CD4 T cells to IL-17-producing Th17 cells. Here, we found that intranasal administration of CT induced migration of migratory dendritic cell (DC) populations, CD103+ DCs and CD11bhi DCs, to the lung draining mediastinal lymph nodes (medLN). Among those DC subsets, CD11bhi DCs that were relatively immature had a major role in Th17 cell differentiation after administration of CT. CT-treated BMDCs showed reduced expression of MHC class II and CD86, similar to CD11bhi DCs in medLN, and these BMDCs promoted Th17 cell differentiation more potently than other BMDCs expressing higher levels of MHC class II and CD86. By analyzing the expression of activation markers such as CD25 and CD69, proliferation and IL-2 production, we determined that CT-treated BMDCs showed diminished antigen-presenting potential to CD4+ T cells compared with normal BMDCs. We also found that CT-stimulated BMDCs promote activin A expression as well as IL-6 and IL-1β, and activin A had a synergic role with TGF-β1 in CT-mediated Th17 cell differentiation. Taken together, our results suggest that CT-stimulated DCs promote Th17 cell differentiation by not only modulating antigen-presenting potential but also inducing Th polarizing cytokines.

Adipose-Derived Stem Cells Promote Peripheral Nerve Regeneration In Vivo without Differentiation into Schwann-Like Lineage.

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Sowa, Yoshihiro; Kishida, Tsunao; Imura, Tetsuya; Numajiri, Toshiaki; Nishino, Kenichi; Tabata, Yasuhiko; Mazda, Osam

2016-02-01

During recent decades, multipotent stem cells were found to reside in the adipose tissue, and these adipose-derived stem cells were shown to play beneficial roles, like those of Schwann cells, in peripheral nerve regeneration. However, it has not been well established whether adipose-derived stem cells offer beneficial effects to peripheral nerve injuries in vivo as Schwann cells do. Furthermore, the in situ survival and differentiation of adipose-derived stem cells after transplantation at the injured peripheral nerve tissue remain to be fully elucidated. Adipose-derived stem cells and Schwann cells were transplanted with gelatin hydrogel tubes at the artificially blunted sciatic nerve lesion in mice. Neuroregenerative abilities of them were comparably estimated. Cre-loxP-mediated fate tracking was performed to visualize survival in vivo of transplanted adipose-derived stem cells and to investigate whether they differentiated into Schwann linage cells at the peripheral nerve injury site. The transplantation of adipose-derived stem cells promoted regeneration of axons, formation of myelin, and restoration of denervation muscle atrophy to levels comparable to those achieved by Schwann cell transplantation. The adipose-derived stem cells survived for at least 4 weeks after transplantation without differentiating into Schwann cells. Transplanted adipose-derived stem cells did not differentiate into Schwann cells but promoted peripheral nerve regeneration at the injured site. The neuroregenerative ability was comparable to that of Schwann cells. Adipose-derived stem cells at an undifferentiated stage may be used as an alternative cell source for autologous cell therapy for patients with peripheral nerve injury.

Resveratrol augments the canonical Wnt signaling pathway in promoting osteoblastic differentiation of multipotent mesenchymal cells

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Zhou, Haibin; Shang, Linshan; Li, Xi; Zhang, Xiyu; Gao, Guimin; Guo, Chenhong; Chen, Bingxi; Liu, Qiji [Key Laboratory of Experimental Teratology, MOE, Institute of Molecular Medicine and Genetics, Shandong University, 44 Wen Hua Xi Lu, Jinan, Shandong 250012 (China); Gong, Yaoqin, E-mail: yxg8@sdu.edu.cn [Key Laboratory of Experimental Teratology, MOE, Institute of Molecular Medicine and Genetics, Shandong University, 44 Wen Hua Xi Lu, Jinan, Shandong 250012 (China); Shao, Changshun, E-mail: shao@biology.rutgers.edu [Key Laboratory of Experimental Teratology, MOE, Institute of Molecular Medicine and Genetics, Shandong University, 44 Wen Hua Xi Lu, Jinan, Shandong 250012 (China); Department of Genetics, Rutgers University, Piscataway, NJ 08854 (United States)

2009-10-15

Resveratrol has been shown to possess many health-benefiting effects, including the promotion of bone formation. In this report we investigated the mechanism by which resveratrol promotes osteoblastic differentiation from pluripotent mesenchymal cells. Since Wnt signaling is well documented to induce osteoblastogenesis and bone formation, we characterized the factors involved in Wnt signaling in response to resveratrol treatment. Resveratrol treatment of mesenchymal cells led to an increase in stabilization and nuclear accumulation of {beta}-catenin dose-dependently and time-dependently. As a consequence of the increased nuclear accumulation of {beta}-catenin, the ability to activate transcription of {beta}-catenin-TCF/LEF target genes that are required for osteoblastic differentiation was upregulated. However, resveratrol did not affect the initial step of the Wnt signaling pathway, as resveratrol was as effective in upregulating the activity of {beta}-catenin in cells in which Lrp5 was knocked down as in control cells. In addition, while conditioned medium enriched in Wnt signaling antagonist Dkk1 was able to inhibit Wnt3a-induced {beta}-catenin upregulation, this inhibitory effect can be abolished in resveratrol-treated cells. Furthermore, we showed that the level of glycogen synthase kinase 3{beta} (GSK-3{beta}), which phosphorylates and destabilizes {beta}-catenin, was reduced in response to resveratrol treatment. The phosphorylation of GSK-3{beta} requires extracellular signal-regulated kinase (ERK)1/2. Together, our data indicate that resveratrol promotes osteoblastogenesis and bone formation by augmenting Wnt signaling.

Resveratrol augments the canonical Wnt signaling pathway in promoting osteoblastic differentiation of multipotent mesenchymal cells

International Nuclear Information System (INIS)

Zhou, Haibin; Shang, Linshan; Li, Xi; Zhang, Xiyu; Gao, Guimin; Guo, Chenhong; Chen, Bingxi; Liu, Qiji; Gong, Yaoqin; Shao, Changshun

2009-01-01

Resveratrol has been shown to possess many health-benefiting effects, including the promotion of bone formation. In this report we investigated the mechanism by which resveratrol promotes osteoblastic differentiation from pluripotent mesenchymal cells. Since Wnt signaling is well documented to induce osteoblastogenesis and bone formation, we characterized the factors involved in Wnt signaling in response to resveratrol treatment. Resveratrol treatment of mesenchymal cells led to an increase in stabilization and nuclear accumulation of β-catenin dose-dependently and time-dependently. As a consequence of the increased nuclear accumulation of β-catenin, the ability to activate transcription of β-catenin-TCF/LEF target genes that are required for osteoblastic differentiation was upregulated. However, resveratrol did not affect the initial step of the Wnt signaling pathway, as resveratrol was as effective in upregulating the activity of β-catenin in cells in which Lrp5 was knocked down as in control cells. In addition, while conditioned medium enriched in Wnt signaling antagonist Dkk1 was able to inhibit Wnt3a-induced β-catenin upregulation, this inhibitory effect can be abolished in resveratrol-treated cells. Furthermore, we showed that the level of glycogen synthase kinase 3β (GSK-3β), which phosphorylates and destabilizes β-catenin, was reduced in response to resveratrol treatment. The phosphorylation of GSK-3β requires extracellular signal-regulated kinase (ERK)1/2. Together, our data indicate that resveratrol promotes osteoblastogenesis and bone formation by augmenting Wnt signaling.

Pairwise comparisons of ten porcine tissues identify differential transcriptional regulation at the gene, isoform, promoter and transcription start site level

International Nuclear Information System (INIS)

Farajzadeh, Leila; Hornshøj, Henrik; Momeni, Jamal; Thomsen, Bo; Larsen, Knud; Hedegaard, Jakob; Bendixen, Christian; Madsen, Lone Bruhn

2013-01-01

Highlights: •Transcriptome sequencing yielded 223 mill porcine RNA-seq reads, and 59,000 transcribed locations. •Establishment of unique transcription profiles for ten porcine tissues including four brain tissues. •Comparison of transcription profiles at gene, isoform, promoter and transcription start site level. •Highlights a high level of regulation of neuro-related genes at both gene, isoform, and TSS level. •Our results emphasize the pig as a valuable animal model with respect to human biological issues. -- Abstract: The transcriptome is the absolute set of transcripts in a tissue or cell at the time of sampling. In this study RNA-Seq is employed to enable the differential analysis of the transcriptome profile for ten porcine tissues in order to evaluate differences between the tissues at the gene and isoform expression level, together with an analysis of variation in transcription start sites, promoter usage, and splicing. Totally, 223 million RNA fragments were sequenced leading to the identification of 59,930 transcribed gene locations and 290,936 transcript variants using Cufflinks with similarity to approximately 13,899 annotated human genes. Pairwise analysis of tissues for differential expression at the gene level showed that the smallest differences were between tissues originating from the porcine brain. Interestingly, the relative level of differential expression at the isoform level did generally not vary between tissue contrasts. Furthermore, analysis of differential promoter usage between tissues, revealed a proportionally higher variation between cerebellum (CBE) versus frontal cortex and cerebellum versus hypothalamus (HYP) than in the remaining comparisons. In addition, the comparison of differential transcription start sites showed that the number of these sites is generally increased in comparisons including hypothalamus in contrast to other pairwise assessments. A comprehensive analysis of one of the tissue contrasts, i

An Alu-like RNA promotes cell differentiation and reduces malignancy of human neuroblastoma cells

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Castelnuovo Manuele; Massone Sara; Tasso Roberta; Fiorino Gloria; Gatti Monica; Robello Mauro; Gatta Elena; Berger Audrey; Strub Katharina; Florio Tullio; Dieci Giorgio; Cancedda Ranieri; Pagano Aldo

2010-01-01

Neuroblastoma (NB) is a pediatric cancer characterized by remarkable cell heterogeneity within the tumor nodules. Here, we demonstrate that the synthesis of a pol III-transcribed noncoding (nc) RNA (NDM29) strongly restricts NB development by promoting cell differentiation, a drop of malignancy processes, and a dramatic reduction of the tumor initiating cell (TIC) fraction in the NB cell population. Notably, the overexpression of NDM29 also confers to malignant NB cells an unpredicted suscept...

Gelatin-Based Hydrogels Promote Chondrogenic Differentiation of Human Adipose Tissue-Derived Mesenchymal Stem Cells In Vitro

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Achim Salamon

2014-02-01

Full Text Available Due to the weak regeneration potential of cartilage, there is a high clinical incidence of articular joint disease, leading to a strong demand for cartilaginous tissue surrogates. The aim of this study was to evaluate a gelatin-based hydrogel for its suitability to support chondrogenic differentiation of human mesenchymal stem cells. Gelatin-based hydrogels are biodegradable, show high biocompatibility, and offer possibilities to introduce functional groups and/or ligands. In order to prove their chondrogenesis-supporting potential, a hydrogel film was developed and compared with standard cell culture polystyrene regarding the differentiation behavior of human mesenchymal stem cells. Cellular basis for this study were human adipose tissue-derived mesenchymal stem cells, which exhibit differentiation potential along the adipogenic, osteogenic and chondrogenic lineage. The results obtained show a promotive effect of gelatin-based hydrogels on chondrogenic differentiation of mesenchymal stem cells in vitro and therefore encourage subsequent in vivo studies.

Innovative biodegradable poly(L-lactide/collagen/hydroxyapatite composite fibrous scaffolds promote osteoblastic proliferation and differentiation

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Zhou GQ

2017-10-01

Full Text Available Guoqiang Zhou,1–3 Sudan Liu,1 Yanyan Ma,1 Wenshi Xu,1 Wei Meng,1 Xue Lin,1 Wenying Wang,1,3 Shuxiang Wang,1–3 Jinchao Zhang1–3 1College of Chemistry and Environmental Science, 2Key Laboratory of Medicinal Chemistry and Molecular Diagnosis of Ministry of Education, 3Key Laboratory of Chemical Biology of Hebei Province, Hebei University, Baoding, Hebei, People’s Republic of China Abstract: The development of an artificial bone graft which can promote the regeneration of fractures or diseased bones is currently the most challenging aspect in bone tissue engineering. To achieve the purpose of promoting bone proliferation and differentiation, the artificial graft needs have a similar structure and composition of extracellular matrix. One-step electrospinning method of biocomposite nanofibers containing hydroxyapatite (HA nanoparticles and collagen (Coll were developed for potential application in bone tissue engineering. Nanocomposite scaffolds of poly(L-lactide (PLLA, PLLA/HA, PLLA/Coll, and PLLA/Coll/HA were fabricated by electrospinning. The morphology, diameter, elements, hydrophilicity, and biodegradability of the composite scaffolds have been investigated. The biocompatibility of different nanocomposite scaffolds was assessed using mouse osteoblasts MC3T3-E1 in vitro, and the proliferation, differentiation, and mineralization of cells on different nanofibrous scaffolds were investigated. The results showed that PLLA/Coll/HA nanofiber scaffolds enhanced cell adhesion, spreading, proliferation, differentiation, mineralization, and gene expression of osteogenic markers compared to other scaffolds. In addition, the nanofibrous scaffolds maintained a stable composition at the beginning of the degradation period and morphology wastage and weight loss were observed when incubated for up to 80 days in physiological simulated conditions. The PLLA/Coll/HA composite nanofibrous scaffolds could be a potential material for guided bone regeneration

CDKL5, a novel MYCN-repressed gene, blocks cell cycle and promotes differentiation of neuronal cells.

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Valli, Emanuele; Trazzi, Stefania; Fuchs, Claudia; Erriquez, Daniela; Bartesaghi, Renata; Perini, Giovanni; Ciani, Elisabetta

2012-01-01

Mutations in the CDKL5 (cyclin-dependent kinase-like 5) gene are associated with a severe epileptic encephalopathy (early infantile epileptic encephalopathy type 2, EIEE2) characterized by early-onset intractable seizures, infantile spasms, severe developmental delay, intellectual disability, and Rett syndrome (RTT)-like features. Despite the clear involvement of CDKL5 mutations in intellectual disability, the function of this protein during brain development and the molecular mechanisms involved in its regulation are still unknown. Using human neuroblastoma cells as a model system we found that an increase in CDKL5 expression caused an arrest of the cell cycle in the G(0)/G(1) phases and induced cellular differentiation. Interestingly, CDKL5 expression was inhibited by MYCN, a transcription factor that promotes cell proliferation during brain development and plays a relevant role in neuroblastoma biology. Through a combination of different and complementary molecular and cellular approaches we could show that MYCN acts as a direct repressor of the CDKL5 promoter. Overall our findings unveil a functional axis between MYCN and CDKL5 governing both neuron proliferation rate and differentiation. The fact that CDKL5 is involved in the control of both neuron proliferation and differentiation may help understand the early appearance of neurological symptoms in patients with mutations in CDKL5. Copyright © 2012 Elsevier B.V. All rights reserved.

Paralogous SQUAMOSA PROMOTER BINDING PROTEIN-LIKE (SPL) genes differentially regulate leaf initiation and reproductive phase change in petunia.

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Preston, Jill C; Jorgensen, Stacy A; Orozco, Rebecca; Hileman, Lena C

2016-02-01

Duplicated petunia clade-VI SPL genes differentially promote the timing of inflorescence and flower development, and leaf initiation rate. The timing of plant reproduction relative to favorable environmental conditions is a critical component of plant fitness, and is often associated with variation in plant architecture and habit. Recent studies have shown that overexpression of the microRNA miR156 in distantly related annual species results in plants with perennial characteristics, including late flowering, weak apical dominance, and abundant leaf production. These phenotypes are largely mediated through the negative regulation of a subset of genes belonging to the SQUAMOSA PROMOTER BINDING PROTEIN-LIKE (SPL) family of transcription factors. In order to determine how and to what extent paralogous SPL genes have partitioned their roles in plant growth and development, we functionally characterized petunia clade-VI SPL genes under different environmental conditions. Our results demonstrate that PhSBP1and PhSBP2 differentially promote discrete stages of the reproductive transition, and that PhSBP1, and possibly PhCNR, accelerates leaf initiation rate. In contrast to the closest homologs in annual Arabidopsis thaliana and Mimulus guttatus, PhSBP1 and PhSBP2 transcription is not mediated by the gibberellic acid pathway, but is positively correlated with photoperiod and developmental age. The developmental functions of clade-VI SPL genes have, thus, evolved following both gene duplication and speciation within the core eudicots, likely through differential regulation and incomplete sub-functionalization.

MiRNA-20a promotes osteogenic differentiation of human mesenchymal stem cells by co-regulating BMP signaling.

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Zhang, Jin-fang; Fu, Wei-ming; He, Ming-liang; Xie, Wei-dong; Lv, Qing; Wan, Gang; Li, Guo; Wang, Hua; Lu, Gang; Hu, Xiang; Jiang, Su; Li, Jian-na; Lin, Marie C M; Zhang, Ya-ou; Kung, Hsiang-fu

2011-01-01

Osteogenic differentiation of mesenchymal stem cells (MSCs) is a complex process, which is regulated by various factors including microRNAs. Our preliminary data showed that the expression of endogenous miR-20a was increased during the course of osteogenic differentiation. Simultaneously, the expression of osteoblast markers and regulators BMP2, BMP4, Runx2, Osx, OCN and OPN was also elevated whereas adipocyte markers PPARγ and osteoblast antagonist, Bambi and Crim1, were downregulated, thereby suggesting that miR-20a plays an important role in regulating osteoblast differentiation. To validate this hypothesis, we tested its effects on osteogenic differentiation by introducing miR-20a mimics and lentiviral-miR20a-expression vectors into hMSCs. We showed that miR-20a promoted osteogenic differentiation by the upregulation of BMP/Runx2 signaling. We performed bioinformatics analysis and predicted that PPARγ, Bambi and Crim1 would be potential targets of miR-20a. PPARγ is a negative regulator of BMP/Runx2 signaling whereas Bambi or Crim1 are antagonists of the BMP pathway. Furthermore, we confirmed that all these molecules were indeed the targets of miR-20a by luciferase reporter, quantitative RT-PCR and western blot assays. Similarly to miR-20a overexpression, the osteogenesis was enhanced by the silence of PPARγ, Bambi or Crim1 by specific siRNAs. Taken together, for the first time, we demonstrated that miR-20a promoted the osteogenesis of hMSCs in a co-regulatory pattern by targeting PPARγ, Bambi and Crim1, the negative regulators of BMP signaling.

Ginsenoside Re Promotes Osteoblast Differentiation in Mouse Osteoblast Precursor MC3T3-E1 Cells and a Zebrafish Model

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Hye-Min Kim

2016-12-01

Full Text Available Bone homeostasis is tightly regulated to balance bone formation and bone resorption. Many anabolic drugs are used as bone-targeted therapeutic agents for the promotion of osteoblast-mediated bone formation or inhibition of osteoclast-mediated bone resorption. Previous studies showed that ginsenoside Re has the effect of the suppression of osteoclast differentiation in mouse bone-marrow derived macrophages and zebrafish. Herein, we investigated whether ginsenoside Re affects osteoblast differentiation and mineralization in in vitro and in vivo models. Mouse osteoblast precursor MC3T3-E1 cells were used to investigate cell viability, alkaline phosphatase (ALP activity, and mineralization. In addition, we examined osteoblastic signaling pathways. Ginsenoside Re affected ALP activity without cytotoxicity, and we also observed the stimulation of osteoblast differentiation through the activation of osteoblast markers including runt-related transcription factor 2, type 1 collagen, ALP, and osteocalcin in MC3T3-E1 cells. Moreover, Alizarin red S staining indicated that ginsenoside Re increased osteoblast mineralization in MC3T3-E1 cells and zebrafish scales compared to controls. These results suggest that ginsenoside Re promotes osteoblast differentiation as well as inhibits osteoclast differentiation, and it could be a potential therapeutic agent for bone diseases.

Possible promotion of neuronal differentiation in fetal rat brain neural progenitor cells after sustained exposure to static magnetism.

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Nakamichi, Noritaka; Ishioka, Yukichi; Hirai, Takao; Ozawa, Shusuke; Tachibana, Masaki; Nakamura, Nobuhiro; Takarada, Takeshi; Yoneda, Yukio

2009-08-15

We have previously shown significant potentiation of Ca(2+) influx mediated by N-methyl-D-aspartate receptors, along with decreased microtubules-associated protein-2 (MAP2) expression, in hippocampal neurons cultured under static magnetism without cell death. In this study, we investigated the effects of static magnetism on the functionality of neural progenitor cells endowed to proliferate for self-replication and differentiate into neuronal, astroglial, and oligodendroglial lineages. Neural progenitor cells were isolated from embryonic rat neocortex and hippocampus, followed by culture under static magnetism at 100 mT and subsequent determination of the number of cells immunoreactive for a marker protein of particular progeny lineages. Static magnetism not only significantly decreased proliferation of neural progenitor cells without affecting cell viability, but also promoted differentiation into cells immunoreactive for MAP2 with a concomitant decrease in that for an astroglial marker, irrespective of the presence of differentiation inducers. In neural progenitors cultured under static magnetism, a significant increase was seen in mRNA expression of several activator-type proneural genes, such as Mash1, Math1, and Math3, together with decreased mRNA expression of the repressor type Hes5. These results suggest that sustained static magnetism could suppress proliferation for self-renewal and facilitate differentiation into neurons through promoted expression of activator-type proneural genes by progenitor cells in fetal rat brain.

Alterations in polyamine levels induced by phorbol diesters and other agents that promote differentiation in human promyelocytic leukemia cells

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Huberman, E.; Weeks, C.; Herrmann, A.; Callaham, M.; Slaga, T.

1981-02-01

Polyamine levels were evaluated in human HL-60 promyelocytic leukemia cells after treatment with inducers of terminal differentiation. Differentiation in these cells was determined by increases in the percentage of morphologically mature cells and in lysozyme activity. Treatment of the HL-60 cells with phorbol 12-myristate-13-acetate (PMA), phorbol 12,13-didecanoate or other inducers of terminal differentiation such as dimethylsulfoxide and retinoic acid resulted in increased levels of putrescine. However, no increase in putrescine could be detected after PMA treatment of a HL-60 cell variant that exhibited a decreased susceptibility to PMA-induced terminal differentiation. Similarly, no increase in putrescine was observed with two nontumor-promoters (phorbol 12,13-diacetate and 4-O-methyl-PMA) or with anthralin, a non-phorbol tumor promoter. In addition to enhancing putrescine levels, PMA also increased the amount of spermidine and decreased the amount of spermine. The increase in putrescine and spermidine preceded the expression of the various differentiation markers. Unlike the changes observed in the polyamine levels after PMA treatment, the activities of ornithine and S-adenosylmethionine decarboxylases, which are polyamine biosynthetic enzymes, did not significantly change. ..cap alpha..-Methylornithine and ..cap alpha..-difluoromethylornithine and methylglyoxal bis(guanylhydrazone), which are inhibitors of the polyamine biosynthetic enzymes, did not affect differentiation in control or PMA-treated cells. Because of these observations, we suggest that the change in polyamine levels involve biochemical pathways other than the known biosynthetic ones. By-products of these pathways may perhaps be the controlling factors involved in the induction of terminal differentiation in the HL-60 and other cell types as well.

TRAF6 promotes myogenic differentiation via the TAK1/p38 mitogen-activated protein kinase and Akt pathways.

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Fang Xiao

Full Text Available p38 mitogen-activated protein kinase (MAPK is an essential kinase involved in myogenic differentiation. Although many substrates of p38 MAPK have been identified, little is known about its upstream activators during myogenic differentiation. TRAF6 is known to function in cytokine signaling during inflammatory responses. However, not much is known about its role in myogenic differentiation and muscle regeneration. We showed here that TRAF6 and its intrinsic ubiquitin E3 ligase activity are required for myogenic differentiation. In mouse myoblasts, knockdown of TRAF6 compromised the p38 MAPK and Akt pathways, while deliberate activation of either pathway rescued the differentiation defect caused by TRAF6 knockdown. TAK1 acted as a key signal transducer downstream of TRAF6 in myogenic differentiation. In vivo, knockdown of TRAF6 in mouse muscles compromised the injury-induced muscle regeneration without impairing macrophage infiltration and myoblast proliferation. Collectively, we demonstrated that TRAF6 promotes myogenic differentiation and muscle regeneration via the TAK1/p38 MAPK and Akt pathways.

MiR-27a Promotes Hemin-Induced Erythroid Differentiation of K562 Cells by Targeting CDC25B

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Dongsheng Wang

2018-03-01

Full Text Available Background/Aims: MicroRNAs (miRNAs play a crucial role in erythropoiesis. MiR-23a∼27a∼24-2 clusters have been proven to take part in erythropoiesis via some proteins. CDC25B (cell division control Cdc2 phosphostase B is also the target of mir-27a; whether it regulates erythropoiesis and its mechanism are unknown. Methods: To evaluate the potential role of miR-27a during erythroid differentiation, we performed miR-27a gain- and loss-of-function experiments on hemin-induced K562 cells. We detected miR-27a expression after hemin stimulation at different time points. At the same time, the γ-globin gene also was measured via real-time PCR. According to the results of the chips, we screened the target protein of miR-27a through a dual-luciferase reporter assay and identified it via Western blot analyses. To evaluate the function of CDC25B, benzidine staining and flow cytometry were employed to detect the cell differentiation and cell cycle. Results: We found that miR-27a promotes hemin-induced erythroid differentiation of human K562 cells by targeting cell division cycle 25 B (CDC25B. Overexpression of miR-27a promotes the differentiation of hemin-induced K562 cells, as demonstrated by γ-globin overexpression. The inhibition of miR-27a expression suppresses erythroid differentiation, thus leading to a reduction in the γ-globin gene. CDC25B was identified as a new target of miR-27a during erythroid differentiation. Overexpression of miR-27a led to decreased CDC25B expression after hemin treatment, and CDC25B was up-regulated when miR-27a expression was inhibited. Moreover, the inhibition of CDC25B affected erythroid differentiation, as assessed by γ-globin expression. Conclusion: This study is the first report of the interaction between miR-27a and CDC25B, and it improves the understanding of miRNA functions during erythroid differentiation.

MicroRNA-24 promotes 3T3-L1 adipocyte differentiation by directly targeting the MAPK7 signaling

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Jin, Min, E-mail: min_jin@zju.edu.cn [Division of Reproductive Medicine & Infertility, The Second Affiliated Hospital, School of Medicine, Zhejiang University, 88#, Jiefang Rd., Hangzhou, Zhejiang, 310009 (China); Wu, Yutao; Wang, Jing [School of Medicine, Zhejiang University, 288# Yuhangtang Rd, Hangzhou, Zhejiang, 310003 (China); Chen, Jian; Huang, Yiting; Rao, Jinpeng; Feng, Chun [Division of Reproductive Medicine & Infertility, The Second Affiliated Hospital, School of Medicine, Zhejiang University, 88#, Jiefang Rd., Hangzhou, Zhejiang, 310009 (China)

2016-05-20

Over the past years, MicroRNAs (miRNAs) act as a vital role in harmony with gene regulation and maintaining cellular homeostasis. It is well testified that miRNAshave been involved in numerous physiological and pathological processes, including embryogenesis, cell fate decision, and cellular differentiation. Adipogenesis is an organized process of cellular differentiation by which pre-adipocytes differentiate towards mature adipocytes, and it is tightly modulated by a series of transcription factors such as peroxisome proliferator-activated receptor γ (PPAR-γ) and sterol regulatory-element binding proteins 1 (SREBP1). However, the molecular mechanisms underlying the connection between miRNAs and adipogenesis-related transcription factors remain obscure. In this study, we unveiled that miR- 24 was remarkably upregulated during 3T3-L1 adipogenesis. Overexpression of miR-24 significantly promoted 3T3-L1 adipogenesis, as evidenced by its ability to increase the expression of PPAR-γ and SREBP1, lipid droplet formation and triglyceride (TG) accumulation. Furthermore, we found that neither ectopic expression of miR-24nor miR-24 inhibitor affect cell proliferation and cell cycle progression. Finally, we demonstrated that miR-24 plays the modulational role by directly repressing MAPK7, a key number in the MAPK signaling pathway. These data indicate that miR-24 is a novel positive regulator of adipocyte differentiation by targeting MAPK7, which provides new insights into the molecular mechanism of miRNA-mediated cellular differentiation. -- Highlights: •We firstly found miR-24 was upregulated in 3T3-L1 pre-adipocytes differentiation. •miR-24 promoted 3T3-L1 pre-adipocytes differentiation while silencing the expression of miR-24 had an opposite function. •miR-24 regulated 3T3-L1 differentiation by directly targeting MAPK7 signaling pathway. •miR-24did not affect 3T3-L1 pre-adipocytes cellular proliferation.

Interleukin-24 induces neuroblastoma SH-SY5Y cell differentiation, growth inhibition, and apoptosis by promoting ROS production.

Science.gov (United States)

Li, Yuan; Zhang, Hongwei; Zhu, Xiaoyu; Feng, Dongchuan; Gong, Jinchao; Han, Tao

2013-11-01

Neuroblastoma is among the most aggressive tumors that occur in childhood and infancy. The clinical prognosis of children with advanced-stage neuroblastoma is still poor. Interleukin-24 (IL-24) is emerging as a new cytokine involved in tumor cellular proliferation, differentiation, and apoptosis and has been widely studied as a tumor inhibitor. However, little is known about this cytokine's role in neuroblastoma. In this study, we investigated the possible effects of IL-24 on inducing neuroblastoma cell differentiation, growth inhibition, and apoptosis in vitro. Our data show that IL-24 promotes neuroblastoma SH-SY5Y cell differentiation, growth inhibition, and apoptosis. Furthermore, we found that the differentiation- and apoptosis-inducing action of IL-24 depends on the accumulation of reactive oxygen species (ROS). These results suggest that IL-24 can induce neuroblastoma cell differentiation and apoptosis and may be a potential therapeutic agent for neuroblastoma.

Bioengineered Bruch's-like extracellular matrix promotes retinal pigment epithelial differentiation

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Samuel McLenachan

2017-07-01

Full Text Available In the eye, the retinal pigment epithelium (RPE adheres to a complex protein matrix known as Bruch's membrane (BrM. The aim of this study was to provide enriched conditions for RPE cell culture through the production of a BrM-like matrix. Our hypothesis was that a human RPE cell line would deposit an extracellular matrix (ECM resembling BrM. The composition and structure of ECM deposited by ARPE19 cells (ARPE19-ECM was characterized. To produce ARPE19-ECM, ARPE19 cells were cultured in the presence dextran sulphate. ARPE19-ECM was decellularized using deoxycholate and characterized by immunostaining and western blot analysis. Primary human RPE and induced pluripotent stem cells were seeded onto ARPE19-ECM or geltrex coated surfaces and examined by microscopy or RT-PCR. Culture of ARPE19 cells with dextran sulphate promoted nuclear localization of SOX2, formation of tight junctions and deposition of ECM. ARPE19 cells deposited ECM proteins found in the inner layers of BrM, including fibronectin, vitronectin, collagens IV and V as well as laminin-alpha-5, but not those found in the middle elastic layer (elastin or the outer layers (collagen VI. ARPE19-ECM promoted pigmentation in human RPE and pluripotent stem cell cultures. Expression of RPE65 was significantly increased on ARPE19-ECM compared with geltrex in differentiating pluripotent stem cell cultures. ARPE19 cells deposit ECM with a composition and structure similar to BrM in the retina. Molecular cues present in ARPE19-ECM promote the acquisition and maintenance of the RPE phenotype. Together, these results demonstrate a simple method for generating a BrM-like surface for enriched RPE cell cultures.

Ibandronate promotes osteogenic differentiation of periodontal ligament stem cells by regulating the expression of microRNAs

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Zhou, Qiang [Department of General Dentistry and Emergency, College of Stomatology, Fourth Military Medical University, Xi' an, Shaanxi 710032 (China); Zhao, Zhi-Ning [Clinical Laboratory, 451 Hospital of Chinese PLA, Xi' an 710054 (China); Cheng, Jing-Tao [Department of Special Dentistry, College of Stomatology, Fourth Military Medical University, Xi' an, Shaanxi 710032 (China); Zhang, Bin [Department of Orthodontics, College of Stomatology, Fourth Military Medical University, Xi' an, Shaanxi 710032 (China); Xu, Jie [Department of Periodontology, College of Stomatology, Fourth Military Medical University, Xi' an, Shaanxi 710032 (China); Huang, Fei; Zhao, Rui-Ni [Department of General Dentistry and Emergency, College of Stomatology, Fourth Military Medical University, Xi' an, Shaanxi 710032 (China); Chen, Yong-Jin, E-mail: cyj1229@fmmu.edu.cn [Department of General Dentistry and Emergency, College of Stomatology, Fourth Military Medical University, Xi' an, Shaanxi 710032 (China)

2011-01-07

Research highlights: {yields} Ibandronate significantly promote the proliferation of PDLSC cells. {yields} Ibandronate enhanced the expression of ALP, COL-1, OPG, OCN, Runx2. {yields} The expression of a class of miRNAs, e.g., miR-18a, miR-133a, miR-141 and miR-19a, was significantly modified in PDLSC cells cultured with ibandronate. {yields} Ibandronate regulates the expression of diverse bone formation-related genes via miRNAs in PDLSCs. {yields} Ibandronate can suppress the activity of osteoclast while promoting the proliferation of osteoblast by regulating the expression of microRNAs. -- Abstract: Bisphosphonates (BPs) have a profound effect on bone resorption and are widely used to treat osteoclast-mediated bone diseases. They suppress bone resorption by inhibiting the activity of mature osteoclasts and/or the formation of new osteoclasts. Osteoblasts may be an alternative target for BPs. Periodontal ligament stem cells (PDLSCs) exhibit osteoblast-like features and are capable of differentiating into osteoblasts or cementoblasts. This study aimed to determine the effects of ibandronate, a nitrogen-containing BP, on the proliferation and the differentiation of PDLSCs and to identify the microRNAs (miRNAs) that mediate these effects. The PDLSCs were treated with ibandronate, and cell proliferation was measured using the MTT (3-dimethylthiazol-2,5-diphenyltetrazolium bromide) assay. The expression of genes and miRNAs involved in osteoblastic differentiation was assayed using quantitative real-time reverse-transcription polymerase chain reaction (qRT-PCR). Ibandronate promoted the proliferation of PDLSCs and enhanced the expression of alkaline phosphatase (ALP), type I collagen (COL-1), osteoprotegerin (OPG), osteocalcin (OCN), and Runx2. The expression of miRNAs, including miR-18a, miR-133a, miR-141 and miR-19a, was significantly altered in the PDLSCs cultured with ibandronate. In PDLSCs, ibandronate regulates the expression of diverse bone formation

Ibandronate promotes osteogenic differentiation of periodontal ligament stem cells by regulating the expression of microRNAs

International Nuclear Information System (INIS)

Zhou, Qiang; Zhao, Zhi-Ning; Cheng, Jing-Tao; Zhang, Bin; Xu, Jie; Huang, Fei; Zhao, Rui-Ni; Chen, Yong-Jin

2011-01-01

Research highlights: → Ibandronate significantly promote the proliferation of PDLSC cells. → Ibandronate enhanced the expression of ALP, COL-1, OPG, OCN, Runx2. → The expression of a class of miRNAs, e.g., miR-18a, miR-133a, miR-141 and miR-19a, was significantly modified in PDLSC cells cultured with ibandronate. → Ibandronate regulates the expression of diverse bone formation-related genes via miRNAs in PDLSCs. → Ibandronate can suppress the activity of osteoclast while promoting the proliferation of osteoblast by regulating the expression of microRNAs. -- Abstract: Bisphosphonates (BPs) have a profound effect on bone resorption and are widely used to treat osteoclast-mediated bone diseases. They suppress bone resorption by inhibiting the activity of mature osteoclasts and/or the formation of new osteoclasts. Osteoblasts may be an alternative target for BPs. Periodontal ligament stem cells (PDLSCs) exhibit osteoblast-like features and are capable of differentiating into osteoblasts or cementoblasts. This study aimed to determine the effects of ibandronate, a nitrogen-containing BP, on the proliferation and the differentiation of PDLSCs and to identify the microRNAs (miRNAs) that mediate these effects. The PDLSCs were treated with ibandronate, and cell proliferation was measured using the MTT (3-dimethylthiazol-2,5-diphenyltetrazolium bromide) assay. The expression of genes and miRNAs involved in osteoblastic differentiation was assayed using quantitative real-time reverse-transcription polymerase chain reaction (qRT-PCR). Ibandronate promoted the proliferation of PDLSCs and enhanced the expression of alkaline phosphatase (ALP), type I collagen (COL-1), osteoprotegerin (OPG), osteocalcin (OCN), and Runx2. The expression of miRNAs, including miR-18a, miR-133a, miR-141 and miR-19a, was significantly altered in the PDLSCs cultured with ibandronate. In PDLSCs, ibandronate regulates the expression of diverse bone formation-related genes via miRNAs. The exact

Human neural stem cells differentiate and promote locomotor recovery in an early chronic spinal cord injury NOD-scid mouse model.

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Desirée L Salazar

2010-08-01

Full Text Available Traumatic spinal cord injury (SCI results in partial or complete paralysis and is characterized by a loss of neurons and oligodendrocytes, axonal injury, and demyelination/dysmyelination of spared axons. Approximately 1,250,000 individuals have chronic SCI in the U.S.; therefore treatment in the chronic stages is highly clinically relevant. Human neural stem cells (hCNS-SCns were prospectively isolated based on fluorescence-activated cell sorting for a CD133(+ and CD24(-/lo population from fetal brain, grown as neurospheres, and lineage restricted to generate neurons, oligodendrocytes and astrocytes. hCNS-SCns have recently been transplanted sub-acutely following spinal cord injury and found to promote improved locomotor recovery. We tested the ability of hCNS-SCns transplanted 30 days post SCI to survive, differentiate, migrate, and promote improved locomotor recovery.hCNS-SCns were transplanted into immunodeficient NOD-scid mice 30 days post spinal cord contusion injury. hCNS-SCns transplanted mice demonstrated significantly improved locomotor recovery compared to vehicle controls using open field locomotor testing and CatWalk gait analysis. Transplanted hCNS-SCns exhibited long-term engraftment, migration, limited proliferation, and differentiation predominantly to oligodendrocytes and neurons. Astrocytic differentiation was rare and mice did not exhibit mechanical allodynia. Furthermore, differentiated hCNS-SCns integrated with the host as demonstrated by co-localization of human cytoplasm with discrete staining for the paranodal marker contactin-associated protein.The results suggest that hCNS-SCns are capable of surviving, differentiating, and promoting improved locomotor recovery when transplanted into an early chronic injury microenvironment. These data suggest that hCNS-SCns transplantation has efficacy in an early chronic SCI setting and thus expands the "window of opportunity" for intervention.

Naringin promotes osteogenic differentiation of bone marrow stromal cells by up-regulating Foxc2 expression via the IHH signaling pathway.

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Lin, Fei-Xiang; Du, Shi-Xin; Liu, De-Zhong; Hu, Qin-Xiao; Yu, Guo-Yong; Wu, Chu-Cheng; Zheng, Gui-Zhou; Xie, Da; Li, Xue-Dong; Chang, Bo

2016-01-01

Naringin is an active compound extracted from Rhizoma Drynariae, and studies have revealed that naringin can promote proliferation and osteogenic differentiation of bone marrow stromal cells (BMSCs). In this study, we explored whether naringin could promote osteogenic differentiation of BMSCs by upregulating Foxc2 expression via the Indian hedgehog (IHH) signaling pathway. BMSCs were cultured in basal medium, basal medium with naringin, osteogenic induction medium, osteogenic induction medium with naringin and osteogenic induction medium with naringin in the presence of the IHH inhibitor cyclopamine (CPE). We examined cell proliferation by using a WST-8 assay, and differentiation by Alizarin Red S staining (for mineralization) and alkaline phosphatase (ALP) activity. In addition, we detected core-binding factor α1 (Cbfα1), osteocalcin (OCN), bone sialoprotein (BSP), peroxisome proliferation-activated receptor gamma 2 (PPARγ2) and Foxc2 expression by using RT-PCR. We also determined Foxc2 and IHH protein levels by western blotting. Naringin increased the mineralization of BMSCs, as shown by Alizarin red S assays, and induced ALP activity. In addition, naringin significantly increased the mRNA levels of Foxc2, Cbfα1, OCN, and BSP, while decreasing PPARγ2 mRNA levels. Furthermore, the IHH inhibitor CPE inhibited the osteogenesis-potentiating effects of naringin. Naringin increased Foxc2 and stimulated the activation of IHH, as evidenced by increased expression of proteins that were inhibited by CPE. Our findings indicate that naringin promotes osteogenic differentiation of BMSCs by up-regulating Foxc2 expression via the IHH signaling pathway.

Novel function of the chromosome 7 open reading frame 41 gene to promote leukemic megakaryocyte differentiation by modulating TPA-induced signaling.

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Sun, X; Lu, B; Hu, B; Xiao, W; Li, W; Huang, Z

2014-03-28

12-O-tetradecanoylphorbol-13-acetate (TPA) activates multiple signaling pathways, alters gene expression and causes leukemic cell differentiation. How TPA-induced genes contribute to leukemic cell differentiation remains elusive. We noticed that chromosome 7 open reading frame 41 (C7ORF41) was a TPA-responsive gene and its upregulation concurred with human megakaryocyte differentiation. In K562 cells, ectopic expression of C7ORF41 significantly increased CD61 expression, enhanced ERK and JNK signaling, and upregulated RUNX1 and FLI1, whereas C7ORF41 knockdown caused an opposite phenotype. These observations suggest that C7ORF41 may promote megakaryocyte differentiation partially through modulating ERK and JNK signaling that leads to upregulation of RUNX1 and FLI1. In supporting this, C7ORF41 overexpression rescued megakaryocyte differentiation blocked by ERK inhibition while JNK inhibition abrogated the upregulation of FLI1 by C7ORF41. Furthermore, we found that Y34F mutant C7ORF41 inhibited megakaryocyte differentiation. nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) was the major activator of C7ORF41 that in turn repressed NF-κB activity by inhibiting its phosphorylation at serine 536, while MAPK/ERK was the potent repressor of C7ORF41. Finally, we showed that C7ORF41 knockdown in mouse fetal liver cells impaired megakaryocyte differentiation. Taken together, we have identified the function of a novel gene C7ORF41 that forms interplaying regulatory network in TPA-induced signaling and promotes leukemic and normal megakaryocyte differentiation.

Novel function of the chromosome 7 open reading frame 41 gene to promote leukemic megakaryocyte differentiation by modulating TPA-induced signaling

International Nuclear Information System (INIS)

Sun, X; Lu, B; Hu, B; Xiao, W; Li, W; Huang, Z

2014-01-01

12-O-tetradecanoylphorbol-13-acetate (TPA) activates multiple signaling pathways, alters gene expression and causes leukemic cell differentiation. How TPA-induced genes contribute to leukemic cell differentiation remains elusive. We noticed that chromosome 7 open reading frame 41 (C7ORF41) was a TPA-responsive gene and its upregulation concurred with human megakaryocyte differentiation. In K562 cells, ectopic expression of C7ORF41 significantly increased CD61 expression, enhanced ERK and JNK signaling, and upregulated RUNX1 and FLI1, whereas C7ORF41 knockdown caused an opposite phenotype. These observations suggest that C7ORF41 may promote megakaryocyte differentiation partially through modulating ERK and JNK signaling that leads to upregulation of RUNX1 and FLI1. In supporting this, C7ORF41 overexpression rescued megakaryocyte differentiation blocked by ERK inhibition while JNK inhibition abrogated the upregulation of FLI1 by C7ORF41. Furthermore, we found that Y34F mutant C7ORF41 inhibited megakaryocyte differentiation. nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) was the major activator of C7ORF41 that in turn repressed NF-κB activity by inhibiting its phosphorylation at serine 536, while MAPK/ERK was the potent repressor of C7ORF41. Finally, we showed that C7ORF41 knockdown in mouse fetal liver cells impaired megakaryocyte differentiation. Taken together, we have identified the function of a novel gene C7ORF41 that forms interplaying regulatory network in TPA-induced signaling and promotes leukemic and normal megakaryocyte differentiation

FGF‐2 promotes osteocyte differentiation through increased E11/podoplanin expression

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Ikpegbu, Ekele; Basta, Lena; Clements, Dylan N.; Fleming, Robert; Vincent, Tonia L.; Buttle, David J.; Pitsillides, Andrew A.; Farquharson, Colin

2018-01-01

E11/podoplanin is critical in the early stages of osteoblast‐to‐osteocyte transitions (osteocytogenesis), however, the upstream events which regulate E11 expression are unknown. The aim of this study was to examine the effects of FGF‐2 on E11‐mediated osteocytogenesis and to reveal the nature of the underlying signaling pathways regulating this process. Exposure of MC3T3 osteoblast‐like cells and murine primary osteoblasts to FGF‐2 (10 ng/ml) increased E11 mRNA and protein expression (p 70% reduction of basal E11 mRNA expression (p < 0.05) and effectively abrogated FGF‐2‐related changes in E11 expression and dendrite formation. FGF‐2 strongly activated the ERK signaling pathway in osteoblast‐like cells but inhibition of this pathway did not block the ability of FGF‐2 to enhance E11 expression or to promote acquisition of the osteocyte phenotype. The results of this study highlight a novel mechanism by which FGF‐2 can regulate osteoblast differentiation and osteocyte formation. Specifically, the data suggests that FGF‐2 promotes osteocytogenesis through increased E11 expression and further studies will identify if this regulatory pathway is essential for bone development and maintenance in health and disease. PMID:29215722

MLL5, a trithorax homolog, indirectly regulates H3K4 methylation, represses cyclin A2 expression, and promotes myogenic differentiation

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Sebastian, Soji; Sreenivas, Prethish; Sambasivan, Ramkumar; Cheedipudi, Sirisha; Kandalla, Prashanth; Pavlath, Grace K.; Dhawan, Jyotsna

2009-01-01

Most cells in adult tissues are nondividing. In skeletal muscle, differentiated myofibers have exited the cell cycle permanently, whereas satellite stem cells withdraw transiently, returning to active proliferation to repair damaged myofibers. We have examined the epigenetic mechanisms operating in conditional quiescence by analyzing the function of a predicted chromatin regulator mixed lineage leukemia 5 (MLL5) in a culture model of reversible arrest. MLL5 is induced in quiescent myoblasts and regulates both the cell cycle and differentiation via a hierarchy of chromatin and transcriptional regulators. Knocking down MLL5 delays entry of quiescent myoblasts into S phase, but hastens S-phase completion. Cyclin A2 (CycA) mRNA is no longer restricted to S phase, but is induced throughout G0/G1, with activation of the cell cycle regulated element (CCRE) in the CycA promoter. Overexpressed MLL5 physically associates with the CCRE and impairs its activity. MLL5 also regulates CycA indirectly: Cux, an activator of CycA promoter and S phase is induced in RNAi cells, and Brm/Brg1, CCRE-binding repressors that promote differentiation are repressed. In knockdown cells, H3K4 methylation at the CCRE is reduced, reflecting quantitative global changes in methylation. MLL5 appears to lack intrinsic histone methyl transferase activity, but regulates expression of histone-modifying enzymes LSD1 and SET7/9, suggesting an indirect mechanism. Finally, expression of muscle regulators Pax7, Myf5, and myogenin is impaired in MLL5 knockdown cells, which are profoundly differentiation defective. Collectively, our results suggest that MLL5 plays an integral role in novel chromatin regulatory mechanisms that suppress inappropriate expression of S-phase-promoting genes and maintain expression of determination genes in quiescent cells. PMID:19264965

Inhibition of Ape1 Redox Activity Promotes Odonto/osteogenic Differentiation of Dental Papilla Cells.

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Chen, Tian; Liu, Zhi; Sun, Wenhua; Li, Jingyu; Liang, Yan; Yang, Xianrui; Xu, Yang; Yu, Mei; Tian, Weidong; Chen, Guoqing; Bai, Ding

2015-12-07

Dentinogenesis is the formation of dentin, a substance that forms the majority of teeth, and this process is performed by odontoblasts. Dental papilla cells (DPCs), as the progenitor cells of odontoblasts, undergo the odontogenic differentiation regulated by multiple cytokines and paracrine signal molecules. Ape1 is a perfect paradigm of the function complexity of a biological macromolecule with two major functional regions for DNA repair and redox regulation, respectively. To date, it remains unclear whether Ape1 can regulate the dentinogenesis in DPCs. In the present study, we firstly examed the spatio-temporal expression of Ape1 during tooth germ developmental process, and found the Ape1 expression was initially high and then gradually reduced along with the tooth development. Secondly, the osteo/odontogenic differentiation capacity of DPCs was up-regulated when treated with either Ape1-shRNA or E3330 (a specific inhibitor of the Ape1 redox function), respectively. Moreover, we found that the canonical Wnt signaling pathway was activated in this process, and E3330 reinforced-osteo/odontogenic differentiation capacity was suppressed by Dickkopf1 (DKK1), a potent antagonist of canonical Wnt signaling pathway. Taken together, we for the first time showed that inhibition of Ape1 redox regulation could promote the osteo/odontogenic differentiation capacity of DPCs via canonical Wnt signaling pathway.

Fucoidan promotes early step of cardiac differentiation from human embryonic stem cells and long-term maintenance of beating areas.

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Hamidi, Sofiane; Letourneur, Didier; Aid-Launais, Rachida; Di Stefano, Antonio; Vainchenker, William; Norol, Françoise; Le Visage, Catherine

2014-04-01

Somatic stem cells require specific niches and three-dimensional scaffolds provide ways to mimic this microenvironment. Here, we studied a scaffold based on Fucoidan, a sulfated polysaccharide known to influence morphogen gradients during embryonic development, to support human embryonic stem cells (hESCs) differentiation toward the cardiac lineage. A macroporous (pore 200 μm) Fucoidan scaffold was selected to support hESCs attachment and proliferation. Using a protocol based on the cardiogenic morphogen bone morphogenic protein 2 (BMP2) and transforming growth factor (TGFβ) followed by tumor necrosis factor (TNFα), an effector of cardiopoietic priming, we examined the cardiac differentiation in the scaffold compared to culture dishes and embryoid bodies (EBs). At day 8, Fucoidan scaffolds supported a significantly higher expression of the 3 genes encoding for transcription factors marking the early step of embryonic cardiac differentiation NKX2.5 (prelease TGFβ and TNFα was confirmed by Luminex technology. We also found that Fucoidan scaffolds supported the late stage of embryonic cardiac differentiation marked by a significantly higher atrial natriuretic factor (ANF) expression (pstress in the soft hydrogel impaired sarcomere formation, as confirmed by molecular analysis of the cardiac muscle myosin MYH6 and immunohistological staining of sarcomeric α-actinin. Nevertheless, Fucoidan scaffolds contributed to the development of thin filaments connecting beating areas through promotion of smooth muscle cells, thus enabling maintenance of beating areas for up to 6 months. In conclusion, Fucoidan scaffolds appear as a very promising biomaterial to control cardiac differentiation from hESCs that could be further combined with mechanical stress to promote sarcomere formation at terminal stages of differentiation.

Diosgenin promotes oligodendrocyte progenitor cell differentiation through estrogen receptor-mediated ERK1/2 activation to accelerate remyelination.

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Xiao, Lin; Guo, Dazhi; Hu, Chun; Shen, Weiran; Shan, Lei; Li, Cui; Liu, Xiuyun; Yang, Wenjing; Zhang, Weidong; He, Cheng

2012-07-01

Differentiation of oligodendrocyte progenitor cells (OPCs) into mature oligodendrocytes is a prerequisite for remyelination after demyelination, and impairment of this process is suggested to be a major reason for remyelination failure. Diosgenin, a plant-derived steroid, has been implicated for therapeutic use in many diseases, but little is known about its effect on the central nervous system. In this study, using a purified rat OPC culture model, we show that diosgenin significantly and specifically promotes OPC differentiation without affecting the viability, proliferation, or migration of OPC. Interestingly, the effect of diosgenin can be blocked by estrogen receptor (ER) antagonist ICI 182780 but not by glucocorticoid and progesterone receptor antagonist RU38486, nor by mineralocorticoid receptor antagonist spirolactone. Moreover, it is revealed that both ER-alpha and ER-beta are expressed in OPC, and diosgenin can activate the extracellular signal-regulated kinase 1/2 (ERK1/2) in OPC via ER. The pro-differentiation effect of diosgenin can also be obstructed by the ERK inhibitor PD98059. Furthermore, in the cuprizone-induced demyelination model, it is demonstrated that diosgenin administration significantly accelerates/enhances remyelination as detected by Luxol fast blue stain, MBP immunohistochemistry and real time RT-PCR. Diosgenin also increases the number of mature oligodendrocytes in the corpus callosum while it does not affect the number of OPCs. Taking together, our results suggest that diosgenin promotes the differentiation of OPC into mature oligodendrocyte through an ER-mediated ERK1/2 activation pathway to accelerate remyelination, which implicates a novel therapeutic usage of this steroidal natural product in demyelinating diseases such as multiple sclerosis (MS). Copyright © 2012 Wiley Periodicals, Inc.

Collagen-derived dipeptide prolyl-hydroxyproline promotes differentiation of MC3T3-E1 osteoblastic cells

International Nuclear Information System (INIS)

Kimira, Yoshifumi; Ogura, Kana; Taniuchi, Yuri; Kataoka, Aya; Inoue, Naoki; Sugihara, Fumihito; Nakatani, Sachie; Shimizu, Jun; Wada, Masahiro; Mano, Hiroshi

2014-01-01

Highlights: • Pro-Hyp did not affect MC3T3-E1 cell proliferation and matrix mineralization. • Pro-Hyp significantly increased alkaline phosphatase activity. • Pro-Hyp significantly upregulated gene expression of Runx2, Osterix, and Col1α1. - Abstract: Prolyl-hydroxyproline (Pro-Hyp) is one of the major constituents of collagen-derived dipeptides. The objective of this study was to investigate the effects of Pro-Hyp on the proliferation and differentiation of MC3T3-E1 osteoblastic cells. Addition of Pro-Hyp did not affect MC3T3-E1 cell proliferation and matrix mineralization but alkaline phosphatase activity was significantly increased. Furthermore, cells treated with Pro-Hyp significantly upregulated gene expression of Runx2, Osterix, and Col1α1. These results indicate that Pro-Hyp promotes osteoblast differentiation. This study demonstrates for the first time that Pro-Hyp has a positive effect on osteoblast differentiation with upregulation of Runx2, Osterix, and Collα1 gene expression

rFN/Cad-11-Modified Collagen Type II Biomimetic Interface Promotes the Adhesion and Chondrogenic Differentiation of Mesenchymal Stem Cells

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Guo, Hongfeng; Zhang, Yuan; Li, Zhengsheng; Kang, Fei; Yang, Bo; Kang, Xia; Wen, Can; Yan, Yanfei; Jiang, Bo; Fan, Yujiang

2013-01-01

Properties of the cell-material interface are determining factors in the successful function of cells for cartilage tissue engineering. Currently, cell adhesion is commonly promoted through the use of polypeptides; however, due to their lack of complementary or modulatory domains, polypeptides must be modified to improve their ability to promote adhesion. In this study, we utilized the principle of matrix-based biomimetic modification and a recombinant protein, which spans fragments 7–10 of fibronectin module III (heterophilic motif ) and extracellular domains 1–2 of cadherin-11 (rFN/Cad-11) (homophilic motif ), to modify the interface of collagen type II (Col II) sponges. We showed that the designed material was able to stimulate cell proliferation and promote better chondrogenic differentiation of rabbit mesenchymal stem cells (MSCs) in vitro than both the FN modified surfaces and the negative control. Further, the Col II/rFN/Cad-11-MSCs composite stimulated cartilage formation in vivo; the chondrogenic effect of Col II alone was much less significant. These results suggested that the rFN/Cad-11-modified collagen type II biomimetic interface has dual biological functions of promoting adhesion and stimulating chondrogenic differentiation. This substance, thus, may serve as an ideal scaffold material for cartilage tissue engineering, enhancing repair of injured cartilage in vivo. PMID:23919505

The Effect of Differentiation and Promotion Toyota Avanza Purchasing Decision in PT. Nasmoco Pemuda Semarang

OpenAIRE

Purnomo, Adityan Dwi; Hadi, Sudharto Prawata; Prabawani, Bulan

2015-01-01

PT. Nasmoco Pemuda Semarang is a company engaged in the marketing of Toyota products for Central Java and Yogyakarta. The tied competition of automotive business led to decreased supposed to be adjective in the number of buyers and many new products from Toyota competitors sells new products with a more elegant design and reasonable price. This study is aimed to identify the driving factors of purchase decisions, specifically differentiation (X1) and promotion (X2) factor on purchasing decisi...

Neurotrophin-3 promotes proliferation and cholinergic neuronal differentiation of bone marrow- derived neural stem cells via notch signaling pathway.

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Yan, Yu-Hui; Li, Shao-Heng; Gao, Zhong; Zou, Sa-Feng; Li, Hong-Yan; Tao, Zhen-Yu; Song, Jie; Yang, Jing-Xian

2016-12-01

Recently, the potential for neural stem cells (NSCs) to be used in the treatment of Alzheimer's disease (AD) has been reported; however, the therapeutic effects are modest by virtue of the low neural differentiation rate. In our study, we transfected bone marrow-derived NSCs (BM-NSCs) with Neurotrophin-3 (NT-3), a superactive neurotrophic factor that promotes neuronal survival, differentiation, and migration of neuronal cells, to investigate the effects of NT-3 gene overexpression on the proliferation and differentiation into cholinergic neuron of BM-NSCs in vitro and its possible molecular mechanism. BM-NSCs were generated from BM mesenchymal cells of adult C57BL/6 mice and cultured in vitro. After transfected with NT-3 gene, immunofluorescence and RT-PCR method were used to determine the ability of BM-NSCs on proliferation and differentiation into cholinergic neuron; Acetylcholine Assay Kit was used for acetylcholine (Ach). RT-PCR and WB analysis were used to characterize mRNA and protein level related to the Notch signaling pathway. We found that NT-3 can promote the proliferation and differentiation of BM-NSCs into cholinergic neurons and elevate the levels of acetylcholine (ACh) in the supernatant. Furthermore, NT-3 gene overexpression increase the expression of Hes1, decreased the expression of Mash1 and Ngn1 during proliferation of BM-NSCs. Whereas, the expression of Hes1 was down-regulated, and Mash1 and Ngn1 expression were up-regulated during differentiation of BM-NSCs. Our findings support the prospect of using NT-3-transduced BM-NSCs in developing therapies for AD due to their equivalent therapeutic potential as subventricular zone-derived NSCs (SVZ-NSCs), greater accessibility, and autogenous attributes. Copyright © 2016 Elsevier Inc. All rights reserved.

EGR1 induces tenogenic differentiation of tendon stem cells and promotes rabbit rotator cuff repair.

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Tao, Xu; Liu, Junpeng; Chen, Lei; Zhou, You; Tang, Kanglai

2015-01-01

The rate of healing failure after surgical repair of chronic rotator cuff tears is considerably high. The aim of this study was to investigate the function of the zinc finger transcription factor early growth response 1 (EGR1) in the differentiation of tendon stem cells (TSCs) and in tendon formation, healing, and tendon tear repair using an animal model of rotator cuff repair. Tenocyte, adipocyte, osteocyte, and chondrocyte differentiation as well as the expression of related genes were determined in EGR1-overexpressing TSCs (EGR1-TSCs) using tissue-specific staining, immunofluorescence staining, quantitative PCR, and western blotting. A rabbit rotator cuff repair model was established, and TSCs and EGR1-TSCs in a fibrin glue carrier were applied onto repair sites. The rabbits were sacrificed 8 weeks after repair operation, and tissues were histologically evaluated and tenocyte-related gene expression was determined. EGR1 induced tenogenic differentiation of TSCs and inhibited non-tenocyte differentiation of TSCs. Furthermore, EGR1 promoted tendon repair in a rabbit model of rotator cuff injury. The BMP12/Smad1/5/8 signaling pathway was involved in EGR1-induced tenogenic differentiation and rotator cuff tendon repair. EGR1 plays a key role in tendon formation, healing, and repair through BMP12/Smad1/5/8 pathway. EGR1-TSCs is a promising treatment for rotator cuff tendon repair surgeries. © 2015 S. Karger AG, Basel.

EGR1 Induces Tenogenic Differentiation of Tendon Stem Cells and Promotes Rabbit Rotator Cuff Repair

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Xu Tao

2015-01-01

Full Text Available Background/Aims: The rate of healing failure after surgical repair of chronic rotator cuff tears is considerably high. The aim of this study was to investigate the function of the zinc finger transcription factor early growth response 1 (EGR1 in the differentiation of tendon stem cells (TSCs and in tendon formation, healing, and tendon tear repair using an animal model of rotator cuff repair. Methods: Tenocyte, adipocyte, osteocyte, and chondrocyte differentiation as well as the expression of related genes were determined in EGR1-overexpressing TSCs (EGR1-TSCs using tissue-specific staining, immunofluorescence staining, quantitative PCR, and western blotting. A rabbit rotator cuff repair model was established, and TSCs and EGR1-TSCs in a fibrin glue carrier were applied onto repair sites. The rabbits were sacrificed 8 weeks after repair operation, and tissues were histologically evaluated and tenocyte-related gene expression was determined. Results: EGR1 induced tenogenic differentiation of TSCs and inhibited non-tenocyte differentiation of TSCs. Furthermore, EGR1 promoted tendon repair in a rabbit model of rotator cuff injury. The BMP12/Smad1/5/8 signaling pathway was involved in EGR1-induced tenogenic differentiation and rotator cuff tendon repair. Conclusion: EGR1 plays a key role in tendon formation, healing, and repair through BMP12/Smad1/5/8 pathway. EGR1-TSCs is a promising treatment for rotator cuff tendon repair surgeries.

Human serum promotes osteogenic differentiation of human dental pulp stem cells in vitro and in vivo.

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Alessandra Pisciotta

Full Text Available Human dental pulp is a promising alternative source of stem cells for cell-based tissue engineering in regenerative medicine, for the easily recruitment with low invasivity for the patient and for the self-renewal and differentiation potential of cells. So far, in vitro culture of mesenchymal stem cells is usually based on supplementing culture and differentiation media with foetal calf serum (FCS. FCS is known to contain a great quantity of growth factors, and thus to promote cell attachment on plastic surface as well as expansion and differentiation. Nevertheless, FCS as an animal origin supplement may represent a potential means for disease transmission besides leading to a xenogenic immune response. Therefore, a significant interest is focused on investigating alternative supplements, in order to obtain a sufficient cell number for clinical application, avoiding the inconvenients of FCS use. In our study we have demonstrated that human serum (HS is a suitable alternative to FCS, indeed its addition to culture medium induces a high hDPSCs proliferation rate and improves the in vitro osteogenic differentiation. Furthermore, hDPSCs-collagen constructs, pre-differentiated with HS-medium in vitro for 10 days, when implanted in immunocompromised rats, are able to restore critical size parietal bone defects. Therefore these data indicate that HS is a valid substitute for FCS to culture and differentiate in vitro hDPSCs in order to obtain a successful bone regeneration in vivo.

FGF-2 promotes osteocyte differentiation through increased E11/podoplanin expression.

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Ikpegbu, Ekele; Basta, Lena; Clements, Dylan N; Fleming, Robert; Vincent, Tonia L; Buttle, David J; Pitsillides, Andrew A; Staines, Katherine A; Farquharson, Colin

2018-07-01

E11/podoplanin is critical in the early stages of osteoblast-to-osteocyte transitions (osteocytogenesis), however, the upstream events which regulate E11 expression are unknown. The aim of this study was to examine the effects of FGF-2 on E11-mediated osteocytogenesis and to reveal the nature of the underlying signaling pathways regulating this process. Exposure of MC3T3 osteoblast-like cells and murine primary osteoblasts to FGF-2 (10 ng/ml) increased E11 mRNA and protein expression (p 70% reduction of basal E11 mRNA expression (p < 0.05) and effectively abrogated FGF-2-related changes in E11 expression and dendrite formation. FGF-2 strongly activated the ERK signaling pathway in osteoblast-like cells but inhibition of this pathway did not block the ability of FGF-2 to enhance E11 expression or to promote acquisition of the osteocyte phenotype. The results of this study highlight a novel mechanism by which FGF-2 can regulate osteoblast differentiation and osteocyte formation. Specifically, the data suggests that FGF-2 promotes osteocytogenesis through increased E11 expression and further studies will identify if this regulatory pathway is essential for bone development and maintenance in health and disease. © 2017 The Authors. Journal of Cellular Physiology Published by Wiley Periodicals, Inc.

Extremely Low-Frequency Electromagnetic Fields Promote In Vitro Neuronal Differentiation and Neurite Outgrowth of Embryonic Neural Stem Cells via Up-Regulating TRPC1

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Ma, Qinlong; Chen, Chunhai; Deng, Ping; Zhu, Gang; Lin, Min; Zhang, Lei; Xu, Shangcheng; He, Mindi; Lu, Yonghui; Duan, Weixia; Pi, Huifeng; Cao, Zhengwang; Pei, Liping; Li, Min; Liu, Chuan; Zhang, Yanwen; Zhong, Min; Zhou, Zhou; Yu, Zhengping

2016-01-01

Exposure to extremely low-frequency electromagnetic fields (ELF-EMFs) can enhance hippocampal neurogenesis in adult mice. However, little is focused on the effects of ELF-EMFs on embryonic neurogenesis. Here, we studied the potential effects of ELF-EMFs on embryonic neural stem cells (eNSCs). We exposed eNSCs to ELF-EMF (50 Hz, 1 mT) for 1, 2, and 3 days with 4 hours per day. We found that eNSC proliferation and maintenance were significantly enhanced after ELF-EMF exposure in proliferation medium. ELF-EMF exposure increased the ratio of differentiated neurons and promoted the neurite outgrowth of eNSC-derived neurons without influencing astrocyes differentiation and the cell apoptosis. In addition, the expression of the proneural genes, NeuroD and Ngn1, which are crucial for neuronal differentiation and neurite outgrowth, was increased after ELF-EMF exposure. Moreover, the expression of transient receptor potential canonical 1 (TRPC1) was significantly up-regulated accompanied by increased the peak amplitude of intracellular calcium level induced by ELF-EMF. Furthermore, silencing TRPC1 expression eliminated the up-regulation of the proneural genes and the promotion of neuronal differentiation and neurite outgrowth induced by ELF-EMF. These results suggest that ELF-EMF exposure promotes the neuronal differentiation and neurite outgrowth of eNSCs via up-regulation the expression of TRPC1 and proneural genes (NeuroD and Ngn1). These findings also provide new insights in understanding the effects of ELF-EMF exposure on embryonic brain development. PMID:26950212

Taurine Promotes the Cartilaginous Differentiation of Human Umbilical Cord-Derived Mesenchymal Stem Cells in Vitro.

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Yao, Xiuhua; Huang, Huiling; Li, Zhou; Liu, Xiaohua; Fan, Weijia; Wang, Xinping; Sun, Xuelian; Zhu, Jianmin; Zhou, Hongrui; Wei, Huaying

2017-08-01

Taurine has been reported to influence osteogenic differentiation, but the role of taurine on cartilaginous differentiation using human umbilical cord-derived mesenchymal stem cells (hUC-MSCs) remains unclear. In this study, we investigated the effect of taurine (0, 1, 5 and 10 mM) on the proliferation and chondrogenesis of hUC-MSCs by analyzing cell proliferation, accumulation of glycosaminoglycans and expression of cartilage specific mRNA. The results show though taurine did not affected the proliferation of hUC-MSCs, 5 mM of taurine is sufficient to enhanced the accumulation of glycosaminoglycans and up-regulate cartilage specific mRNA expression, namely collagen type II, aggrecan and SOX9. Taurine also inhibits chondrocyte dedifferentiation by reducing expression of collagen type I mRNA. Taken together, our study reveals that taurine promotes and maintains the chondrogenesis of hUC-MSCs.

A new avenue to the synthesis of GAG-mimicking polymers highly promoting neural differentiation of embryonic stem cells.

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Wang, Mengmeng; Lyu, Zhonglin; Chen, Gaojian; Wang, Hongwei; Yuan, Yuqi; Ding, Kaiguo; Yu, Qian; Yuan, Lin; Chen, Hong

2015-10-28

A new strategy for the fabrication of glycosaminoglycan (GAG) analogs was proposed by copolymerizing the sulfonated unit and the glyco unit, 'splitted' from the sulfated saccharide building blocks of GAGs. The synthetic polymers can promote cell proliferation and neural differentiation of embryonic stem cells with the effects even better than those of heparin.

Fibro-vascular coupling in the control of cochlear blood flow.

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Min Dai

Full Text Available Transduction of sound in the cochlea is metabolically demanding. The lateral wall and hair cells are critically vulnerable to hypoxia, especially at high sound levels, and tight control over cochlear blood flow (CBF is a physiological necessity. Yet despite the importance of CBF for hearing, consensus on what mechanisms are involved has not been obtained.We report on a local control mechanism for regulating inner ear blood flow involving fibrocyte signaling. Fibrocytes in the super-strial region are spatially distributed near pre-capillaries of the spiral ligament of the albino guinea pig cochlear lateral wall, as demonstrably shown in transmission electron microscope and confocal images. Immunohistochemical techniques reveal the inter-connected fibrocytes to be positive for Na+/K+ ATPase β1 and S100. The connected fibrocytes display more Ca(2+ signaling than other cells in the cochlear lateral wall as indicated by fluorescence of a Ca(2+ sensor, fluo-4. Elevation of Ca(2+ in fibrocytes, induced by photolytic uncaging of the divalent ion chelator o-nitrophenyl EGTA, results in propagation of a Ca(2+ signal to neighboring vascular cells and vasodilation in capillaries. Of more physiological significance, fibrocyte to vascular cell coupled signaling was found to mediate the sound stimulated increase in cochlear blood flow (CBF. Cyclooxygenase-1 (COX-1 was required for capillary dilation.The findings provide the first evidence that signaling between fibrocytes and vascular cells modulates CBF and is a key mechanism for meeting the cellular metabolic demand of increased sound activity.

Rho kinase inhibitor Y-27632 promotes the differentiation of human bone marrow mesenchymal stem cells into keratinocyte-like cells in xeno-free conditioned medium.

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Li, Zhenzhen; Han, Shichao; Wang, Xingqin; Han, Fu; Zhu, Xiongxiang; Zheng, Zhao; Wang, Hongtao; Zhou, Qin; Wang, Yunchuan; Su, Linlin; Shi, Jihong; Tang, Chaowu; Hu, Dahai

2015-03-11

Bone marrow mesenchymal stem cells (BMSCs), which have the ability to self-renew and to differentiate into multiple cell types, have recently become a novel strategy for cell-based therapies. The differentiation of BMSCs into keratinocytes may be beneficial for patients with burns, disease, or trauma. However, the currently available cells are exposed to animal materials during their cultivation and induction. These xeno-contaminations severely limit their clinical outcomes. Previous studies have shown that the Rho kinase (ROCK) inhibitor Y-27632 can promote induction efficiency and regulate the self-renewal and differentiation of stem cells. In the present study, we attempted to establish a xeno-free system for the differentiation of BMSCs into keratinocytes and to investigate whether Y-27632 can facilitate this differentiation. BMSCs isolated from patients were cultured by using a xeno-free system and characterised by using flow cytometric analysis and adipogenic and osteogenic differentiation assays. Human primary keratinocytes were also isolated from patients. Then, the morphology, population doubling time, and β-galactosidase staining level of these cells were evaluated in the presence or absence of Y-27632 to determine the effects of Y-27632 on the state of the keratinocytes. Keratinocyte-like cells (KLCs) were detected at different time points by immunocytofluorescence analysis. Moreover, the efficiency of BMSC differentiation under different conditions was measured by quantitative real-time-polymerase chain reaction (RT-PCR) and Western blot analyses. The ROCK inhibitor Y-27632 promoted the proliferation and lifespan of human primary keratinocytes. In addition, we showed that keratinocyte-specific markers could be detected in BMSCs cultured in a xeno-free system using keratinocyte-conditioned medium (KCM) independent of the presence of Y-27632. However, the efficiency of the differentiation of BMSCs into KLCs was significantly higher in the presence of Y

IGF-1 Promotes Brn-4 Expression and Neuronal Differentiation of Neural Stem Cells via the PI3K/Akt Pathway

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Zhang, Xinhua; Zhang, Lei; Cheng, Xiang; Guo, Yuxiu; Sun, Xiaohui; Chen, Geng; Li, Haoming; Li, Pengcheng; Lu, Xiaohui; Tian, Meiling; Qin, Jianbing; Zhou, Hui; Jin, Guohua

2014-01-01

Our previous studies indicated that transcription factor Brn-4 is upregulated in the surgically denervated hippocampus in vivo, promoting neuronal differentiation of hippocampal neural stem cells (NSCs) in vitro. The molecules mediating Brn-4 upregulation in the denervated hippocampus remain unknown. In this study we examined the levels of insulin-like growth factor-1 (IGF-1) in hippocampus following denervation. Surgical denervation led to a significant increase in IGF-1 expression in vivo. We also report that IGF-1 treatment on NSCs in vitro led to a marked acceleration of Brn-4 expression and cell differentiation down neuronal pathways. The promotion effects were blocked by PI3K-specific inhibitor (LY294002), but not MAPK inhibitor (PD98059); levels of phospho-Akt were increased by IGF-1 treatment. In addition, inhibition of IGF-1 receptor (AG1024) and mTOR (rapamycin) both attenuated the increased expression of Brn-4 induced by IGF-1. Together, the results demonstrated that upregulation of IGF-1 induced by hippocampal denervation injury leads to activation of the PI3K/Akt signaling pathway, which in turn gives rise to upregulation of the Brn-4 and subsequent stem cell differentiation down neuronal pathways. PMID:25474202

Hypoxia, leukocytes, and the pulmonary circulation.

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Stenmark, Kurt R; Davie, Neil J; Reeves, John T; Frid, Maria G

2005-02-01

Data are rapidly accumulating in support of the idea that circulating monocytes and/or mononuclear fibrocytes are recruited to the pulmonary circulation of chronically hypoxic animals and that these cells play an important role in the pulmonary hypertensive process. Hypoxic induction of monocyte chemoattractant protein-1, stromal cell-derived factor-1, vascular endothelial growth factor-A, endothelin-1, and tumor growth factor-beta(1) in pulmonary vessel wall cells, either directly or indirectly via signals from hypoxic lung epithelial cells, may be a critical first step in the recruitment of circulating leukocytes to the pulmonary circulation. In addition, hypoxic stress appears to induce release of increased numbers of monocytic progenitor cells from the bone marrow, and these cells may have upregulated expression of receptors for the chemokines produced by the lung circulation, which thus facilitates their specific recruitment to the pulmonary site. Once present, macrophages/fibrocytes may exert paracrine effects on resident pulmonary vessel wall cells stimulating proliferation, phenotypic modulation, and migration of resident fibroblasts and smooth muscle cells. They may also contribute directly to the remodeling process through increased production of collagen and/or differentiation into myofibroblasts. In addition, they could play a critical role in initiating and/or supporting neovascularization of the pulmonary artery vasa vasorum. The expanded vasa network may then act as a conduit for further delivery of circulating mononuclear cells to the pulmonary arterial wall, creating a feedforward loop of pathological remodeling. Future studies will need to determine the mechanisms that selectively induce leukocyte/fibrocyte recruitment to the lung circulation under hypoxic conditions, their direct role in the remodeling process via production of extracellular matrix and/or differentiation into myofibroblasts, their impact on the phenotype of resident smooth muscle

The Differential Effects of Social Media Sites for Promoting Cancer Risk Reduction.

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Lauckner, Carolyn; Whitten, Pamela

2016-09-01

Social media are potentially valuable tools for disseminating cancer education messages, but the differential effects of various sites on persuasive outcomes are unknown. In an effort to inform future health promotion, this research tested the effects of Facebook, YouTube, Twitter, and blogs for delivering a cancer risk reduction message. Using an experimental design, participants were randomly placed in several conditions that delivered the same message but with different forms of social media. Effects on comprehension and attitudes were examined, as they are important variables in the behavior change process. YouTube led to higher comprehension and stronger attitudes toward cancer risk reduction than Twitter, but there were no differences between other sites. Additionally, YouTube led to stronger attitudes toward cancer risk reduction as compared to Facebook, but not any other sites. These results demonstrate that, even if the message is kept constant, the form of social media used to deliver content can have an effect on persuasive outcomes. More research is needed to determine the mechanisms behind the differences found, however. Altogether, this line of research is valuable for any individuals seeking to use social media for health promotion purposes and could have direct implications for the development of cancer risk reduction campaigns.

miR-148a-3p Mediates Notch Signaling to Promote the Differentiation and M1 Activation of Macrophages

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Fei Huang

2017-10-01

Full Text Available The Notch pathway plays critical roles in the differentiation and polarized activation of macrophages; however, the downstream molecular mechanisms underlying Notch activity in macrophages remain elusive. Our previous study has identified a group of microRNAs that mediate Notch signaling to regulate macrophage activation and tumor-associated macrophages (TAMs. In this study, we demonstrated that miR-148a-3p functions as a novel downstream molecule of Notch signaling to promote the differentiation of monocytes into macrophages in the presence of granulocyte macrophage colony-stimulating factor (GM-CSF. Meanwhile, miR-148a-3p promoted M1 and inhibited M2 polarization of macrophages upon Notch activation. Macrophages overexpressing miR-148a-3p exhibited enhanced ability to engulf and kill bacteria, which was mediated by excessive production of reactive oxygen species (ROS. Further studies using reporter assay and Western blotting identified Pten as a direct target gene of miR-148a-3p in macrophages. Macrophages overexpressing miR-148a-3p increased their ROS production through the PTEN/AKT pathway, likely to defend against bacterial invasion. Moreover, miR-148a-3p also enhanced M1 macrophage polarization and pro-inflammatory responses through PTEN/AKT-mediated upregulation of NF-κB signaling. In summary, our data establish a novel molecular mechanism by which Notch signaling promotes monocyte differentiation and M1 macrophage activation through miR-148a-3p, and suggest that miR-148a-3p-modified monocytes or macrophages are potential new tools for the treatment of inflammation-related diseases.

Pairwise comparisons of ten porcine tissues identify differential transcriptional regulation at the gene, isoform, promoter and transcription start site level

DEFF Research Database (Denmark)

Farajzadeh, Leila; Hornshøj, Henrik; Momeni, Jamal

2013-01-01

, isoform, and transcription start site (TSS), and promoter level showed that several of the genes differed at all four levels. Interestingly, these genes were mainly annotated to the "electron transport chain" and neuronal differentiation, emphasizing that "tissue important" genes are regulated at several...

TET-Catalyzed 5-Hydroxymethylation Precedes HNF4A Promoter Choice during Differentiation of Bipotent Liver Progenitors

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Pierre-Benoit Ancey

2017-07-01

Full Text Available Understanding the processes that govern liver progenitor cell differentiation has important implications for the design of strategies targeting chronic liver diseases, whereby regeneration of liver tissue is critical. Although DNA methylation (5mC and hydroxymethylation (5hmC are highly dynamic during early embryonic development, less is known about their roles at later stages of differentiation. Using an in vitro model of hepatocyte differentiation, we show here that 5hmC precedes the expression of promoter 1 (P1-dependent isoforms of HNF4A, a master transcription factor of hepatocyte identity. 5hmC and HNF4A expression from P1 are dependent on ten-eleven translocation (TET dioxygenases. In turn, the liver pioneer factor FOXA2 is necessary for TET1 binding to the P1 locus. Both FOXA2 and TETs are required for the 5hmC-related switch in HNF4A expression. The epigenetic event identified here may be a key step for the establishment of the hepatocyte program by HNF4A.

Inhibition of c-Myc overcomes cytotoxic drug resistance in acute myeloid leukemia cells by promoting differentiation.

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Xiao-Na Pan

Full Text Available Nowadays, drug resistance still represents a major obstacle to successful acute myeloid leukemia (AML treatment and the underlying mechanism is not fully elucidated. Here, we found that high expression of c-Myc was one of the cytogenetic characteristics in the drug-resistant leukemic cells. c-Myc over-expression in leukemic cells induced resistance to chemotherapeutic drugs, enhanced colony formation capacity and inhibited cell differentiation induced by all-trans retinoic acid (ATRA. Meanwhile, inhibition of c-Myc by shRNA or specific c-Myc inhibitor 10058-F4 rescued the sensitivity to cytotoxic drugs, restrained the colony formation ability and promoted differentiation. RT-PCR and western blotting analysis showed that down-regulation of C/EBPβ contributed to the poor differentiation state of leukemic cells induced by c-Myc over-expression. Importantly, over-expression of C/EBPβ could reverse c-Myc induced drug resistance. In primary AML cells, the c-Myc expression was negatively correlated with C/EBPβ. 10058-F4, displayed anti-proliferative activity and increased cellular differentiation with up-regulation of C/EBPβ in primary AML cells. Thus, our study indicated that c-Myc could be a novel target to overcome drug resistance, providing a new approach in AML therapy.

Romidepsin Promotes Osteogenic and Adipocytic Differentiation of Human Mesenchymal Stem Cells through Inhibition of Histondeacetylase Activity

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Dalia Ali

2018-01-01

Full Text Available Bone marrow mesenchymal stem cells (BMSCs are adult multipotent stem cells that can differentiate into mesodermal lineage cells, including adipocytes and osteoblasts. However, the epigenetic mechanisms governing the lineage-specific commitment of BMSCs into adipocytes or osteoblasts are under investigation. Herein, we investigated the epigenetic effect of romidepsin, a small molecule dual inhibitor targeting HDAC1 and HDAC2 identified through an epigenetic library functional screen. BMSCs exposed to romidepsin (5 nM exhibited enhanced adipocytic and osteoblastic differentiation. Global gene expression and signaling pathway analyses of differentially expressed genes revealed a strong enrichment of genes involved in adipogenesis and osteogenesis in romidepsin-treated BMSCs during induction into adipocytes or osteoblasts, respectively. Pharmacological inhibition of FAK signaling during adipogenesis or inhibition of FAK or TGFβ signaling during osteogenesis diminished the biological effects of romidepsin on BMSCs. The results of chromatin immunoprecipitation combined with quantitative polymerase chain reaction indicated a significant increase in H3K9Ac epigenetic markers in the promoter regions of peroxisome proliferator-activated receptor gamma (PPARγ and KLF15 (related to adipogenesis or SP7 (Osterix and alkaline phosphatase (ALP (related to osteogenesis in romidepsin-treated BMSCs. Our data indicated that romidepsin is a novel in vitro modulator of adipocytic and osteoblastic differentiation of BMSCs.

Schwann cells promote neuronal differentiation of bone marrow ...

African Journals Online (AJOL)

Administrator

2011-04-25

Apr 25, 2011 ... Bone marrow stromal cells (BMSCs), a type of multipotent stem cell, can differentiate into various types ... induced to differentiate into neuron-like cells when they are ... axonal regeneration and functional reconstruction do not.

Human amnion mesenchymal stem cells promote proliferation and osteogenic differentiation in human bone marrow mesenchymal stem cells.

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Wang, Yuli; Yin, Ying; Jiang, Fei; Chen, Ning

2015-02-01

Human amnion mesenchymal stem cells (HAMSCs) can be obtained from human amniotic membrane, a highly abundant and readily available tissue. HAMSC sources present fewer ethical issues, have low immunogenicity, anti-inflammatory properties, considerable advantageous characteristics, and are considered an attractive potential treatment material in the field of regenerative medicine. We used a co-culture system to determine whether HAMSCs could promote osteogenesis in human bone marrow mesenchymal stem cells (HBMSCs). We isolated HAMSCs from discarded amnion samples and collected them using pancreatin/collagenase digestion. We cultured HAMSCs and HBMSCSs in basal medium. Activity of alkaline phosphatase (ALP), an early osteogenesis marker, was increased in the co-culture system compared to the control single cultures, which we also confirmed by ALP staining. We used immunofluorescence testing to investigate the effects of co-culturing with HAMSCs on HBMSC proliferation, which revealed that the co-culturing enhanced EdU expression in HBMSCs. Western blotting and quantitative real-time PCR indicated that co-culturing promoted osteogenesis in HBMSCs. Furthermore, Alizarin red S staining revealed that extracellular matrix calcium levels in mineralized nodule formation produced by the co-cultures were higher than that in the controls. Using the same co-culture system, we further observed the effects of HAMSCs on osteogenic differentiation in primary osteoblasts by Western blotting, which better addressed the mechanism for HAMSCs in bone regeneration. The results showed HAMSCs are osteogenic and not only play a role in promoting HBMSC proliferation and osteogenic differentiation but also in osteoblasts, laying the foundation for new regenerative medicine methods.

Hydrostatic pressure promotes the proliferation and osteogenic/chondrogenic differentiation of mesenchymal stem cells: The roles of RhoA and Rac1

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Yin-Hua Zhao

2015-05-01

Full Text Available Our previous studies have shown that hydrostatic pressure can serve as an active regulator for bone marrow mesenchymal stem cells (BMSCs. The current work further investigates the roles of cytoskeletal regulatory proteins Ras homolog gene family member A (RhoA and Ras-related C3 botulinum toxin substrate 1 (Rac1 in hydrostatic pressure-related effects on BMSCs. Flow cytometry assays showed that the hydrostatic pressure promoted cell cycle initiation in a RhoA- and Rac1-dependent manner. Furthermore, fluorescence assays confirmed that RhoA played a positive and Rac1 displayed a negative role in the hydrostatic pressure-induced F-actin stress fiber assembly. Western blots suggested that RhoA and Rac1 play central roles in the pressure-inhibited ERK phosphorylation, and Rac1 but not RhoA was involved in the pressure-promoted JNK phosphorylation. Finally, real-time polymerase chain reaction (PCR experiments showed that pressure promoted the expression of osteogenic marker genes in BMSCs at an early stage of osteogenic differentiation through the up-regulation of RhoA activity. Additionally, the PCR results showed that pressure enhanced the expression of chondrogenic marker genes in BMSCs during chondrogenic differentiation via the up-regulation of Rac1 activity. Collectively, our results suggested that RhoA and Rac1 are critical to the pressure-induced proliferation and differentiation, the stress fiber assembly, and MAPK activation in BMSCs.

Hydrostatic pressure promotes the proliferation and osteogenic/chondrogenic differentiation of mesenchymal stem cells: The roles of RhoA and Rac1.

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Zhao, Yin-Hua; Lv, Xin; Liu, Yan-Li; Zhao, Ying; Li, Qiang; Chen, Yong-Jin; Zhang, Min

2015-05-01

Our previous studies have shown that hydrostatic pressure can serve as an active regulator for bone marrow mesenchymal stem cells (BMSCs). The current work further investigates the roles of cytoskeletal regulatory proteins Ras homolog gene family member A (RhoA) and Ras-related C3 botulinum toxin substrate 1 (Rac1) in hydrostatic pressure-related effects on BMSCs. Flow cytometry assays showed that the hydrostatic pressure promoted cell cycle initiation in a RhoA- and Rac1-dependent manner. Furthermore, fluorescence assays confirmed that RhoA played a positive and Rac1 displayed a negative role in the hydrostatic pressure-induced F-actin stress fiber assembly. Western blots suggested that RhoA and Rac1 play central roles in the pressure-inhibited ERK phosphorylation, and Rac1 but not RhoA was involved in the pressure-promoted JNK phosphorylation. Finally, real-time polymerase chain reaction (PCR) experiments showed that pressure promoted the expression of osteogenic marker genes in BMSCs at an early stage of osteogenic differentiation through the up-regulation of RhoA activity. Additionally, the PCR results showed that pressure enhanced the expression of chondrogenic marker genes in BMSCs during chondrogenic differentiation via the up-regulation of Rac1 activity. Collectively, our results suggested that RhoA and Rac1 are critical to the pressure-induced proliferation and differentiation, the stress fiber assembly, and MAPK activation in BMSCs. Copyright © 2015. Published by Elsevier B.V.

CUDC-907 Promotes Bone Marrow Adipocytic Differentiation Through Inhibition of Histone Deacetylase and Regulation of Cell Cycle.

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Ali, Dalia; Alshammari, Hassan; Vishnubalaji, Radhakrishnan; Chalisserry, Elna Paul; Hamam, Rimi; Alfayez, Musaad; Kassem, Moustapha; Aldahmash, Abdullah; Alajez, Nehad M

2017-03-01

The role of bone marrow adipocytes (BMAs) in overall energy metabolism and their effects on bone mass are currently areas of intensive investigation. BMAs differentiate from bone marrow stromal cells (BMSCs); however, the molecular mechanisms regulating BMA differentiation are not fully understood. In this study, we investigated the effect of CUDC-907, identified by screening an epigenetic small-molecule library, on adipocytic differentiation of human BMSCs (hBMSCs) and determined its molecular mechanism of action. Human bone marrow stromal cells exposed to CUDC-907 (500 nM) exhibited enhanced adipocytic differentiation (∼2.9-fold increase, P < 0.005) compared with that of control cells. Global gene expression and signaling pathway analyses of differentially expressed genes revealed a strong enrichment of genes involved in adipogenesis, cell cycle, and DNA replication. Chromatin immune precipitation combined with quantitative polymerase chain reaction showed significant increase in H3K9ac epigenetic marker in the promoter regions of AdipoQ, FABP4, PPARγ, KLF15, and CEBPA in CUDC-907-treated hBMSCs. Follow-up experiments corroborated that the inhibition of histone deacetylase (HDAC) activity enhanced adipocytic differentiation, while the inhibition of PI3K decreased adipocytic differentiation. In addition, CUDC-907 arrested hBMSCs in the G0-G1 phase of the cell cycle and reduced the number of S-phase cells. Our data reveal that HDAC, PI3K, and cell cycle genes are important regulators of BMA formation and demonstrate that adipocyte differentiation of hBMSCs is associated with complex changes in a number of epigenetic and genetic pathways, which can be targeted to regulate BMA formation.

Hypoxic Culture Promotes Dopaminergic-Neuronal Differentiation of Nasal Olfactory Mucosa Mesenchymal Stem Cells via Upregulation of Hypoxia-Inducible Factor-1α.

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Zhuo, Yi; Wang, Lei; Ge, Lite; Li, Xuan; Duan, Da; Teng, Xiaohua; Jiang, Miao; Liu, Kai; Yuan, Ting; Wu, Pei; Wang, Hao; Deng, Yujia; Xie, Huali; Chen, Ping; Xia, Ying; Lu, Ming

2017-08-01

Olfactory mucosa mesenchymal stem cells (OM-MSCs) display significant clonogenic activity and may be easily propagated for Parkinson's disease therapies. Methods of inducing OM-MSCs to differentiate into dopaminergic (DAergic) neurons using olfactory ensheathing cells (OECs) are thus an attractive topic of research. We designed a hypoxic induction protocol to generate DAergic neurons from OM-MSCs using a physiological oxygen (O 2 ) level of 3% and OEC-conditioned medium (OCM; HI group). The normal induction (NI) group was cultured in O 2 at ambient air level (21%). The role of hypoxia-inducible factor-1α (HIF-1α) in the differentiation of OM-MSCs under hypoxia was investigated by treating cells with an HIF-1α inhibitor before induction (HIR group). The proportions of β-tubulin- and tyrosine hydroxylase (TH)-positive cells were significantly increased in the HI group compared with the NI and HIR groups, as shown by immunocytochemistry and Western blotting. Furthermore, the level of dopamine was significantly increased in the HI group. A slow outward potassium current was recorded in differentiated cells after 21 d of induction using whole-cell voltage-clamp tests. A hypoxic environment thus promotes OM-MSCs to differentiate into DAergic neurons by increasing the expression of HIF-1α and by activating downstream target gene TH. This study indicated that OCM under hypoxic conditions could significantly upregulate key transcriptional factors involved in the development of DAergic neurons from OM-MSCs, mediated by HIF-1α. Hypoxia promotes DAergic neuronal differentiation of OM-MSCs, and HIF-1α may play an important role in hypoxia-inducible pathways during DAergic lineage specification and differentiation in vitro.

Dickkopf1 Up-Regulation Induced by a High Concentration of Dexamethasone Promotes Rat Tendon Stem Cells to Differentiate Into Adipocytes

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Wan Chen

2015-11-01

Full Text Available Background/Aims: Dexamethasone (Dex-induced spontaneous tendon rupture and decreased self-repair capability is very common in clinical practice. The metaplasia of adipose tissue in the ruptured tendon indicates that Dex may induce tendon stem cells (TSCs to differentiate into adipocytes, but the mechanism remains unclear. In the present study, we used in vitro methods to investigate the effects of Dex on rat TSC differentiation and the molecular mechanisms underlying this process. Methods: First, we used qPCR and Western blotting to detect the expression of the adipogenic differentiation markers aP2 and C/EBPα after treating the TSCs with Dex. Oil red staining was used to confirm that high concentration Dex promoted adipogenic differentiation of rat TSCs. Next, we used qPCR and Western blotting to detect the effect of a high concentration of dexamethasone on molecules related to the canonical WNT/β-catenin pathway in TSCs. Results: Treating rat TSCs with Dex promoted the synthesis of the inhibitory molecule dickkopf1 (DKK1 at the mRNA and protein levels. Western blotting results further showed that Dex downregulated the cellular signaling molecule phosphorylated glycogen synthase kinase-3β (P-GSK-3 β (ser9, upregulated P-GSK-3β (tyr216, and downregulated the pivotal signaling molecule β-catenin. Furthermore, DKK1 knockdown attenuated Dex-induced inhibition of the canonical WNT/β-catenin pathway and of the adipogenic differentiation of TSCs. Lithium chloride (LiCl, a GSK-3β inhibitor reduced Dex-induced inhibition of the classical WNT/β-catenin pathway in TSCs and of the differentiation of TSCs to adipocytes. Conclusion: In conclusion, by upregulating DKK1 expression, reducing the level of P-GSK-3β (ser9, and increasing the level of P-GSK-3β (tyr216, Dex causes the degradation of β-catenin, the central molecule of the classical WNT pathway, thereby inducing rat TSCs to differentiate into adipocytes.

Enhanced differentiation of neural stem cells to neurons and promotion of neurite outgrowth by oxygen-glucose deprivation.

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Wang, Qin; Yang, Lin; Wang, Yaping

2015-06-01

Stroke has become the leading cause of mortality worldwide. Hypoxic or ischemic insults are crucial factors mediating the neural damage in the brain tissue of stroke patients. Neural stem cells (NSCs) have been recognized as a promising tool for the treatment of ischemic stroke and other neurodegenerative diseases due to their inducible pluripotency. In this study, we aim to mimick the cerebral hypoxic-ischemic injury in vitro using oxygen-glucose deprivation (OGD) strategy, and evaluate the effects of OGD on the NSC's neural differentiation, as well as the differentiated neurite outgrowth. Our data showed that NSCs under the short-term 2h OGD treatment are able to maintain cell viability and the capability to form neurospheres. Importantly, this moderate OGD treatment promotes NSC differentiation to neurons and enhances the performance of the mature neuronal networks, accompanying increased neurite outgrowth of differentiated neurons. However, long-term 6h and 8h OGD exposures in NSCs lead to decreased cell survival, reduced differentiation and diminished NSC-derived neurite outgrowth. The expressions of neuron-specific microtubule-associated protein 2 (MAP-2) and growth associated protein 43 (GAP-43) are increased by short-term OGD treatments but suppressed by long-term OGD. Overall, our results demonstrate that short-term OGD exposure in vitro induces differentiation of NSCs while maintaining their proliferation and survival, providing valuable insights of adopting NSC-based therapy for ischemic stroke and other neurodegenerative disorders. Copyright © 2015 Elsevier Ltd. All rights reserved.

TSH-Mediated TNFα Production in Human Fibrocytes Is Inhibited by Teprotumumab, an IGF-1R Antagonist.

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Hong Chen

Full Text Available Fibrocytes (FC are bone marrow-derived progenitor cells that are more abundant and infiltrate the thyroid and orbit in Graves orbitopathy (GO. FCs express high levels of thyrotropin receptor (TSHR and insulin-like growth factor-1 receptor (IGF-1R. These receptors are physically and functionally associated, but their role in GO pathogenesis is not fully delineated. Treatment of FCs with thyroid stimulating hormone (TSH or M22 (activating antibody to TSHR induces the production of numerous cytokines, including tumor necrosis factor α (TNFα. Teprotumumab (TMB is a human monoclonal IGF-1R blocking antibody currently in clinical trial for GO and inhibits TSHR-mediated actions in FCs.To characterize the molecular mechanisms underlying TSH-induced TNFα production by FCs, and the role of IGF-1R blockade by TMB.FCs from healthy and GD patients were treated with combinations of TSH, M22, MG132 and AKTi (inhibitors of NF-κB and Akt, respectively, and TMB. TNFα protein production was measured by Luminex and flow cytometry. Messenger RNA expression was quantified by real time PCR.Treatment with TSH/M22 induced TNFα protein and mRNA production by FCs, both of which were reduced when FCs were pretreated with MG132 and AKTi (p<0.0001. TMB decreased TSH-induced TNFα protein production in circulating FCs from mean fluorescent index (MFI value of 2.92 to 1.91, and mRNA expression in cultured FCs from 141- to 52-fold expression (p<0.0001. TMB also decreased M22-induced TNFα protein production from MFI of 1.67 to 1.12, and mRNA expression from 6- to 3-fold expression (p<0.0001.TSH/M22 stimulates FC production of TNFα mRNA and protein. This process involves the transcription factor NF-κB and its regulator Akt. Blocking IGF-1R attenuates TSH/M22-induced TNFα production. This further delineates the interaction of TSHR and IGF1-R signaling pathways. By modulating the proinflammatory properties of FCs such as TNFα production, TMB may be a promising

IGF-1 promotes Brn-4 expression and neuronal differentiation of neural stem cells via the PI3K/Akt pathway.

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Xinhua Zhang

Full Text Available Our previous studies indicated that transcription factor Brn-4 is upregulated in the surgically denervated hippocampus in vivo, promoting neuronal differentiation of hippocampal neural stem cells (NSCs in vitro. The molecules mediating Brn-4 upregulation in the denervated hippocampus remain unknown. In this study we examined the levels of insulin-like growth factor-1 (IGF-1 in hippocampus following denervation. Surgical denervation led to a significant increase in IGF-1 expression in vivo. We also report that IGF-1 treatment on NSCs in vitro led to a marked acceleration of Brn-4 expression and cell differentiation down neuronal pathways. The promotion effects were blocked by PI3K-specific inhibitor (LY294002, but not MAPK inhibitor (PD98059; levels of phospho-Akt were increased by IGF-1 treatment. In addition, inhibition of IGF-1 receptor (AG1024 and mTOR (rapamycin both attenuated the increased expression of Brn-4 induced by IGF-1. Together, the results demonstrated that upregulation of IGF-1 induced by hippocampal denervation injury leads to activation of the PI3K/Akt signaling pathway, which in turn gives rise to upregulation of the Brn-4 and subsequent stem cell differentiation down neuronal pathways.

Inhibition of mitogen-activated protein kinase kinase, DNA methyltransferase, and transforming growth factor-β promotes differentiation of human induced pluripotent stem cells into enterocytes.

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Kodama, Nao; Iwao, Takahiro; Kabeya, Tomoki; Horikawa, Takashi; Niwa, Takuro; Kondo, Yuki; Nakamura, Katsunori; Matsunaga, Tamihide

2016-06-01

We previously reported that small-molecule compounds were effective in generating pharmacokinetically functional enterocytes from human induced pluripotent stem (iPS) cells. In this study, to determine whether the compounds promote the differentiation of human iPS cells into enterocytes, we investigated the effects of a combination of mitogen-activated protein kinase kinase (MEK), DNA methyltransferase (DNMT), and transforming growth factor (TGF)-β inhibitors on intestinal differentiation. Human iPS cells cultured on feeder cells were differentiated into endodermal cells by activin A. These endodermal-like cells were then differentiated into intestinal stem cells by fibroblast growth factor 2. Finally, the cells were differentiated into enterocyte cells by epidermal growth factor and small-molecule compounds. After differentiation, mRNA expression levels and drug-metabolizing enzyme activities were measured. The mRNA expression levels of the enterocyte marker sucrase-isomaltase and the major drug-metabolizing enzyme cytochrome P450 (CYP) 3A4 were increased by a combination of MEK, DNMT, and TGF-β inhibitors. The mRNA expression of CYP3A4 was markedly induced by 1α,25-dihydroxyvitamin D3. Metabolic activities of CYP1A1/2, CYP2B6, CYP2C9, CYP2C19, CYP3A4/5, UDP-glucuronosyltransferase, and sulfotransferase were also observed in the differentiated cells. In conclusion, MEK, DNMT, and TGF-β inhibitors can be used to promote the differentiation of human iPS cells into pharmacokinetically functional enterocytes. Copyright © 2016 The Japanese Society for the Study of Xenobiotics. Published by Elsevier Ltd. All rights reserved.

Electro-acupuncture promotes survival, differentiation of the bone marrow mesenchymal stem cells as well as functional recovery in the spinal cord-transected rats

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Ding, Ying; Yan, Qing; Ruan, Jing-Wen; Zhang, Yan-Qing; Li, Wen-Jie; Zhang, Yu-Jiao; Li, Yan; Dong, Hongxin; Zeng, Yuan-Shan

2009-01-01

Background Bone marrow mesenchymal stem cells (MSCs) are one of the potential tools for treatment of the spinal cord injury; however, the survival and differentiation of MSCs in an injured spinal cord still need to be improved. In the present study, we investigated whether Governor Vessel electro-acupuncture (EA) could efficiently promote bone marrow mesenchymal stem cells (MSCs) survival and differentiation, axonal regeneration and finally, functional recovery in the transected spinal cord. Results The spinal cords of adult Sprague-Dawley (SD) rats were completely transected at T10, five experimental groups were performed: 1. sham operated control (Sham-control); 2. operated control (Op-control); 3. electro-acupuncture treatment (EA); 4. MSCs transplantation (MSCs); and 5. MSCs transplantation combined with electro-acupuncture (MSCs+EA). After 2-8 weeks of MSCs transplantation plus EA treatment, we found that the neurotrophin-3 (NT-3), cAMP level, the differentiation of MSCs, the 5-HT positive and CGRP positive nerve fibers in the lesion site and nearby tissue of injured spinal cord were significantly increased in the MSCs+EA group as compared to the group of the MSCs transplantation or the EA treated alone. Furthermore, behavioral test and spinal cord evoked potentials detection demonstrated a significantly functional recovery in the MSCs +EA group. Conclusion These results suggest that EA treatment may promote grafted MSCs survival and differentiation; MSCs transplantation combined with EA treatment could promote axonal regeneration and partial locomotor functional recovery in the transected spinal cord in rats and indicate a promising avenue of treatment of spinal cord injury. PMID:19374777

3,4-Oxo-isopropylidene-shikimic acid promotes adiopkine expression during murine 3T3-L1 fibroblast differentiation into adipocytes

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Shifen Dong

2014-10-01

Conclusions: These findings demonstrated that ISA promoted adipogenesis by up-regulating expressions of C/EBP β, PPAR γ, C/EBP α, aP2 and FAS, and also stimulated adipokines during adipocyte differentiation. Further study should clarify the relationship between stimulation of adipokines and cognitive enhancing effect of ISA.

Cross-reacting antibacterial auto-antibodies are produced within coronary atherosclerotic plaques of acute coronary syndrome patients.

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Filippo Canducci

Full Text Available Coronary atherosclerosis, the main condition predisposing to acute myocardial infarction, has an inflammatory component caused by stimuli that are yet unknown. We molecularly investigated the nature of the immune response within human coronary lesion in four coronary plaques obtained by endoluminal atherectomy from four patients. We constructed phage-display libraries containing the IgG1/kappa antibody fragments produced by B-lymphocytes present in each plaque. By immunoaffinity, we selected from these libraries a monoclonal antibody, arbitrarily named Fab7816, able to react both with coronary and carotid atherosclerotic tissue samples. We also demonstrated by confocal microscopy that this monoclonal antibody recognized human transgelin type 1, a cytoskeleton protein involved in atherogenesis, and that it co-localized with fibrocyte-like cells transgelin+, CD68+, CD45+ in human sections of coronary and carotid plaques. In vitro fibrocytes obtained by differentiating CD14+ cells isolated from peripheral blood mononuclear cells also interacted with Fab7816, thus supporting the hypothesis of a specific recognition of fibrocytes into the atherosclerotic lesions. Interestingly, the same antibody, cross-reacted with the outer membrane proteins of Proteus mirabilis and Klebsiella pneumoniae (and possibly with homologous proteins of other enterobacteriaceae present in the microbiota. From all the other three libraries, we were able to clone, by immunoaffinity selection, human monoclonal antibodies cross-reacting with bacterial outer membrane proteins and with transgelin. These findings demonstrated that in human atherosclerotic plaques a local cross-reactive immune response takes place.

Schwann cells promote neuronal differentiation of bone marrow ...

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It has been suggested that the BMSCs have the capacity to differentiate into neurons under specific experimental conditions, using chemical factors. In this study, we showed that BMSCs can be induced to differentiate into neuron-like cells when they are co-cultured with Schwann cells by Brdu pulse label technology.

Diclofenac and triamcinolone acetonide impair tenocytic differentiation and promote adipocytic differentiation of mesenchymal stem cells.

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Fredriksson, Maritha; Li, Yan; Stålman, Anders; Haldosén, Lars-Arne; Felländer-Tsai, Li

2013-09-02

Tendinopathies are often empirically treated with oral/topical nonsteroidal anti-inflammatory medications and corticosteroid injections despite their unclear effects on tendon regeneration. Recent studies indicate that tendon progenitors exhibit stem cell-like properties, i.e., differentiation to osteoblasts, adipocytes, and chondrocytes, in addition to tenocytes. Our present study aims at understanding the effects of triamcinolone acetonide and diclofenac on tenocytic differentiation of mesenchymal stem cells. The murine fibroblast C3H10T1/2 cell line was induced to tenocytic differentiation by growth differentiation factor-7. Cell proliferation and differentiation with the exposure of different concentrations of triamcinolone acetonide and diclofenac were measured by WST-1 assay and real-time polymerase chain reaction analysis, respectively. Cell proliferation was decreased in a concentration-dependent manner when exposed to triamcinolone acetonide and diclofenac. In addition to tenocytic differentiation, adipocyte formation was observed, both at gene expression and microscopic level, when the cells were exposed to triamcinolone acetonide or high concentrations of diclofenac. Our results indicate that triamcinolone acetonide and diclofenac might alter mesenchymal stem cell differentiation in a nonfavorable way regarding tendon regeneration; therefore, these medications should be used with more caution clinically.

Differentiation of human stem cells is promoted by amphiphilic pluronic block copolymers

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Doğan A

2012-09-01

Full Text Available Aysegül Doğan,1 Mehmet E Yalvaç,1,2 Fikrettin Şahin,1 Alexander V Kabanov,3–5 András Palotás,6 Albert A Rizvanov71Department of Genetics and BioEngineering, College of Engineering and Architecture, Yeditepe University, Istanbul, Turkey; 2Center for Gene Therapy, Nationwide Children's Hospital, Ohio State University, Columbus, OH, USA; 3Center for Drug Delivery and Nanomedicine, 4Department of Pharmaceutical Sciences, College of Pharmacy, Durham Research Center, University of Nebraska Medical Center, Omaha, NE, USA; 5Laboratory of Chemical Design of Bio-nano-materials, Department of Chemistry, Mikhail V Lomonosov Moscow State University, Moscow, Russia; 6Asklepios-Med, Szeged, Hungary; 7Institute of Fundamental Medicine and Biology, Kazan (Volga Region Federal University, Kazan, RussiaAbstract: Stem cell usage provides novel avenues of tissue regeneration and therapeutics across disciplines. Apart from ethical considerations, the selection and amplification of donor stem cells remain a challenge. Various biopolymers with a wide range of properties have been used extensively to deliver biomolecules such as drugs, growth factors and nucleic acids, as well as to provide biomimetic surface for cellular adhesion. Using human tooth germ stem cells with high proliferation and transformation capacity, we have investigated a range of biopolymers to assess their potential for tissue engineering. Tolerability, toxicity, and their ability to direct differentiation were evaluated. The majority of pluronics, consisting of both hydrophilic and hydrophobic poly(ethylene oxide chains, either exerted cytotoxicity or had no significant effect on human tooth germ stem cells; whereas F68 increased the multi-potency of stem cells, and efficiently transformed them into osteogenic, chondrogenic, and adipogenic tissues. The data suggest that differentiation and maturation of stem cells can be promoted by selecting the appropriate mechanical and chemical

Cocaine- and amphetamine-regulated transcript promotes the differentiation of mouse bone marrow-derived mesenchymal stem cells into neural cells

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Jin Jiali

2011-07-01

Full Text Available Abstract Background Neural tissue has limited potential to self-renew after neurological damage. Cell therapy using BM-MSCs (bone marrow mesenchymal stromal cells seems like a promising approach for the treatment of neurological diseases. However, the neural differentiation of stem cells influenced by massive factors and interactions is not well studied at present. Results In this work, we isolated and identified MSCs from mouse bone marrow. Co-cultured with CART (0.4 nM for six days, BM-MSCs were differentiated into neuron-like cells by the observation of optical microscopy. Immunofluorescence demonstrated that the differentiated BM-MSCs expressed neural specific markers including MAP-2, Nestin, NeuN and GFAP. In addition, NeuN positive cells could co-localize with TH or ChAT by double-labled immunofluorescence and Nissl bodies were found in several differentiated cells by Nissl stain. Furthermore, BDNF and NGF were increased by CART using RT-PCR. Conclusion This study demonstrated that CART could promote the differentiation of BM-MSCs into neural cells through increasing neurofactors, including BNDF and NGF. Combined application of CART and BM-MSCs may be a promising cell-based therapy for neurological diseases.

Cysticerci drive dendritic cells to promote in vitro and in vivo Tregs differentiation.

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Adalid-Peralta, Laura; Arce-Sillas, Asiel; Fragoso, Gladis; Cárdenas, Graciela; Rosetti, Marcos; Casanova-Hernández, Didier; Rangel-Escareño, Claudia; Uribe-Figueroa, Laura; Fleury, Agnes; Sciutto, Edda

2013-01-01

Regulatory T cells (Tregs) play a crucial role in immune homeostasis. Treg induction is a strategy that parasites have evolved to modulate the host's inflammatory environment, facilitating their establishment and permanence. In human Taenia solium neurocysticercosis (NC), the concurrence of increased peripheral and central Treg levels and their capacity to inhibit T cell activation and proliferation support their role in controlling neuroinflammation. This study is aimed at identifing possible mechanisms of Treg induction in human NC. Monocyte-derived dendritic cells (DC) from healthy human donors, cocultivated with autologous CD4(+) naïve cells either in the presence or absence of cysticerci, promoted CD25(high)Foxp3+ Treg differentiation. An increased Treg induction was observed when cysticerci were present. Moreover, an augmentation of suppressive-related molecules (SLAMF1, B7-H1, and CD205) was found in parasite-induced DC differentiation. Increased Tregs and a higher in vivo DC expression of the regulatory molecules SLAMF1 and CD205 in NC patients were also found. SLAMF1 gene was downregulated in NC patients with extraparenchymal cysticerci, exhibiting higher inflammation levels than patients with parenchymal parasites. Our findings suggest that cysticerci may modulate DC to favor a suppressive environment, which may help parasite establishment, minimizing the excessive inflammation, which may lead to tissue damage.

A new diarylheptanoid from Alpinia officinarum promotes the differentiation of 3T3-L1 preadipocytes.

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Zhang, Xuguang; Zhang, Xiaopo; Wang, Yong; Chen, Feng; Li, Youbin; Li, Yonghui; Tan, Yinfeng; Gong, Jingwen; Zhong, Xia; Li, Hailong; Zhang, Junqing

2018-03-01

A new diarylheptanoid, namely trans-(4R,5S)-epoxy-1,7-diphenyl-3-heptanone (1), and a new natural product, 7-(4″-hydroxy-3″-methoxyphenyl)-1-phenyl-hepta-4E,6E-dien-3-one (2), were obtained from the aqueous extract of Alpinia officinarum Hance, together with three other diarylheptanoids, 5-hydroxy-1,7-diphenyl-3-heptanone (3), 1,7-diphenyl-4E-en-3-heptanone (4) and 5-methoxy-1,7-diphenyl-3-heptanone (5). The structures were characterised mainly by analysing their physical data including IR, NMR and HRMS. This study highlights that the 4,5-epoxy moiety in 1 is rarely seen in diarylheptanoids. In addition, the five isolates were tested for their differentiation activity of 3T3-L1 preadipocytes. The results showed that these compounds could dose-dependently promote adipocyte differentiation without cytotoxicity (IC 50  > 100 μM).

microRNA-145 promotes differentiation in human urothelial carcinoma through down-regulation of syndecan-1

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Fujii, Tomomi; Shimada, Keiji; Tatsumi, Yoshihiro; Hatakeyama, Kinta; Obayashi, Chiho; Fujimoto, Kiyohide; Konishi, Noboru

2015-01-01

A new molecular marker of carcinoma in the urinary bladder is needed as a diagnostic tool or as a therapeutic target. Potential markers include microRNAs (miRNAs), which are short, low molecular weight RNAs 19–24 nt long that regulate genes associated with cell proliferation, differentiation, and development in various cancers. In this study, we investigated the molecular mechanisms by which miR-145 promotes survival of urothelial carcinoma cells and differentiation into multiple lineages. We found miR-145 to regulate expression of syndecan-1, a heparin sulfate proteoglycan. Cell proliferation in the human urothelial carcinoma cell lines T24 and KU7 was assessed by MTS assay. Cellular senescence and apoptosis were measured by senescence-associated β-galactosidase (SA-β-gal) and TUNEL assay, respectively. Quantitative RT-PCR was used to measure mRNA expression of various genes, including syndecan-1, stem cell factors, and markers of differentiation into squamous, glandular, or neuroendocrine cells. Overexpression of miR-145 induced cell senescence, and thus significantly inhibited cell proliferation in T24 and KU7 cells. Syndecan-1 expression diminished, whereas stem cell markers such as SOX2, NANOG, OCT4, and E2F3 increased. miR-145 also up-regulated markers of differentiation into squamous (p63, TP63, and CK5), glandular (MUC-1, MUC-2, and MUC-5 AC), and neuroendocrine cells (NSE and UCHL-1). Finally, expression of miR-145 was down-regulated in high-grade urothelial carcinomas, but not in low-grade tumors. Results indicate that miR-145 suppresses syndecan-1 and, by this mechanism, up-regulates stem cell factors and induces cell senescence and differentiation. We propose that miR-145 may confer stem cell-like properties on urothelial carcinoma cells and thus facilitate differentiation into multiple cell types. The online version of this article (doi:10.1186/s12885-015-1846-0) contains supplementary material, which is available to authorized users

Low magnitude high frequency vibration promotes adipogenic differentiation of bone marrow stem cells via P38 MAPK signal.

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Qian Zhao

Full Text Available Low magnitude high frequency vibration (LMHFV has been mainly reported for its influence on the musculoskeletal system, particularly the bone tissue. In the bone structure, osteogenic activity is the main focus of study with regards to LMHFV. However, adipogenesis, another important mode of differentiation in the bone marrow cavity that might be affected by LMHFV, is much less researched. Furthermore, the molecular mechanism of how LMHFV influences adipogenesis still needs to be understood. Here, we tested the effect of LMHFV (0.3g, 40 Hz, amplitude: 50μm, 15min/d, on multipotent stem cells (MSCs, which are the common progenitors of osteogenic, chondrogenic, adipogenic and myogenic cells. It is previously shown that LMHFV promotes osteogenesis of MSCs. In this study, we further revealed its effect on adipo-differentiation of bone marrow stem cells (BMSCs and studied the underlying signaling pathway. We found that when treated with LMHFV, the cells showed a higher expression of PPARγ, C/EBPα, adiponectin and showed more oil droplets. After vibration, the protein expression of PPARγ increased, and the phosphorylation of p38 MAPK was enhanced. After treating cells with SB203580, a specific p38 inhibitor, both the protein level of PPARγ illustrated by immunofluorescent staining and the oil droplets number, were decreased. Altogether, this indicates that p38 MAPK is activated during adipogenesis of BMSCs, and this is promoted by LMHFV. Our results demonstrating that specific parameters of LMHFV promotes adipogenesis of MSCs and enhances osteogenesis, highlights an unbeneficial side effect of vibration therapy used for preventing obesity and osteoporosis.

EWS Knockdown and Taxifolin Treatment Induced Differentiation and Removed DNA Methylation from p53 Promoter to Promote Expression of Puma and Noxa for Apoptosis in Ewing's Sarcoma.

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Hossain, Mohammad Motarab; Ray, Swapan Kumar

2014-10-01

Ewing's sarcoma is a pediatric tumor that mainly occurs in soft tissues and bones. Malignant characteristics of Ewing's sarcoma are correlated with expression of EWS oncogene. We achieved knockdown of EWS expression using a plasmid vector encoding EWS short hairpin RNA (shRNA) to increase anti-tumor mechanisms of taxifolin (TFL), a new flavonoid, in human Ewing's sarcoma cells in culture and animal models. Immunofluorescence microscopy and flow cytometric analysis showed high expression of EWS in human Ewing's sarcoma SK-N-MC and RD-ES cell lines. EWS shRNA plus TFL inhibited 80% cell viability and caused the highest decreases in EWS expression at mRNA and protein levels in both cell lines. Knockdown of EWS expression induced morphological features of differentiation. EWS shRNA plus TFL caused more alterations in molecular markers of differentiation than either agent alone. EWS shRNA plus TFL caused the highest decreases in cell migration with inhibition of survival, angiogenic and invasive factors. Knockdown of EWS expression was associated with removal of DNA methylation from p53 promoter, promoting expression of p53, Puma, and Noxa. EWS shRNA plus TFL induced the highest amounts of apoptosis with activation of extrinsic and intrinsic pathways in both cell lines in culture. EWS shRNA plus TFL also inhibited growth of Ewing's sarcoma tumors in animal models due to inhibition of differentiation inhibitors and angiogenic and invasive factors and also induction of activation of caspase-3 for apoptosis. Collectively, knockdown of EWS expression increased various anti-tumor mechanisms of TFL in human Ewing's sarcoma in cell culture and animal models.

Lactoferrin promote primary rat osteoblast proliferation and differentiation via up-regulation of insulin-like growth factor-1 expression.

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Hou, Jian-ming; Wu, Man; Lin, Qing-ming; Lin, Fan; Xue, Ying; Lan, Xu-hua; Chen, En-yu; Wang, Mei-li; Yang, Hai-yan; Wang, Feng-xiong

2014-08-01

The aim of this study was to explore the effect of lactoferrin (LF) in primary fetal rat osteoblasts proliferation and differentiation and investigate the underlying molecular mechanisms. Primary rat osteoblasts were obtained from the calvarias of neonatal rats. Osteoblasts were treated with LF (0.1-1000 μg/mL), or OSI-906 [a selective inhibitor of insulin-like growth factor 1 (IGF-1) receptor and insulin receptor]. The IGF-1 was then knocked down by small hairpin RNA (shRNA) technology and then was treated with recombinant human IGF-1 or LF. Cell proliferation and differentiation were measured by MTT assay and alkaline phosphatase (ALP) assay, respectively. The expression of IGF-1 and IGF binding protein 2 (IGFBP2) mRNA were analyzed using real-time PCR. LF promotes the proliferation and differentiation of osteoblasts in a certain range (1-100 μg/mL) in time- and dose-dependent manner. The mRNA level of IGF-1 was significantly increased, while the expression of IGFBP2 was suppressed by LF treatment. Knockdown of IGF-1 by shRNA in primary rat osteoblast dramatically decreased the abilities of proliferation and differentiation of osteoblasts and blocked the proliferation and differentiation effect of LF in osteoblasts. OSI906 (5 μM) blocked the mitogenic and differentiation of LF in osteoblasts. Proliferation and differentiation of primary rat osteoblasts in response to LF are mediated in part by stimulating of IGF-1 gene expression and alterations in the gene expression of IGFBP2.

Nanotopography Promotes Pancreatic Differentiation of Human Embryonic Stem Cells and Induced Pluripotent Stem Cells.

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Kim, Jong Hyun; Kim, Hyung Woo; Cha, Kyoung Je; Han, Jiyou; Jang, Yu Jin; Kim, Dong Sung; Kim, Jong-Hoon

2016-03-22

Although previous studies suggest that nanotopographical features influence properties and behaviors of stem cells, only a few studies have attempted to derive clinically useful somatic cells from human pluripotent stem cells using nanopatterned surfaces. In the present study, we report that polystyrene nanopore-patterned surfaces significantly promote the pancreatic differentiation of human embryonic and induced pluripotent stem cells. We compared different diameters of nanopores and showed that 200 nm nanopore-patterned surfaces highly upregulated the expression of PDX1, a critical transcription factor for pancreatic development, leading to an approximately 3-fold increase in the percentage of differentiating PDX1(+) pancreatic progenitors compared with control flat surfaces. Furthermore, in the presence of biochemical factors, 200 nm nanopore-patterned surfaces profoundly enhanced the derivation of pancreatic endocrine cells producing insulin, glucagon, or somatostatin. We also demonstrate that nanopore-patterned surface-induced upregulation of PDX1 is associated with downregulation of TAZ, suggesting the potential role of TAZ in nanopore-patterned surface-mediated mechanotransduction. Our study suggests that appropriate cytokine treatments combined with nanotopographical stimulation could be a powerful tool for deriving a high purity of desired cells from human pluripotent stem cells.

Histone deacetylase 4 promotes TGF-beta1-induced synovium-derived stem cell chondrogenesis but inhibits chondrogenically differentiated stem cell hypertrophy.

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Pei, Ming; Chen, Demeng; Li, Jingting; Wei, Lei

2009-12-01

The transforming growth factor-beta (TGF-beta) superfamily members play diverse roles in cartilage development and maintenance. TGF-beta up-regulates chondrogenic gene expression by enhancing transcription factor SRY (sex determining region Y)-box 9 (Sox9) and inhibits osteoblast differentiation by repressing runt-related transcription factor 2 (Runx2). Recently, histone deacetylases (HDACs) were reported to act as negative regulators of chondrocyte hypertrophy. It was speculated that HDAC4 may promote TGF-beta1-induced MSC chondrogenesis. In this study, the adenovirus-mediated HDAC4 gene (Ad.HDAC4) was utilized to infect synovium-derived stem cells (SDSCs). Adenovirus-mediated LacZ (Ad.LacZ) served as a control. The infected cells were centrifuged to form SDSC pellets followed by incubation in a serum-free chondrogenic medium for 15 days with or without 10ng/mL TGF-beta1. Transfection efficiency was determined in SDSCs using Ad.LacZ. Cytotoxicity was measured using lactate dehydrogenase assay. Histology, immunostaining, biochemical analysis, and real-time polymerase chain reaction were performed to assess chondrogenesis at protein and mRNA levels in infected SDSCs. Our data demonstrated that supplementation with TGF-beta1 could initiate and promote SDSC chondrogenesis; however, TGF-beta1 alone was insufficient to fully differentiate SDSCs into chondrocytes. Ad.HDAC4 could be efficiently transfected into SDSCs. Without TGF-beta1 treatment, HDAC4 had no effect on SDSC chondrogenesis; however, in the presence of TGF-beta1, HDAC4 could speed up and maintain a high level of chondrogenesis while down-regulating the hypertrophic marker - type X collagen expression. This study is the first report showing that HDAC4 overexpression promotes TGF-beta1-induced SDSC chondrogenesis but inhibits chondrogenically differentiated stem cell hypertrophy. The mechanism underlying this process needs further investigation.

Cyr61 induces IL-6 production by fibroblast-like synoviocytes promoting Th17 differentiation in rheumatoid arthritis.

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Lin, Jinpiao; Zhou, Zhou; Huo, Rongfen; Xiao, Lianbo; Ouyang, Guilin; Wang, Li; Sun, Yue; Shen, Baihua; Li, Dangsheng; Li, Ningli

2012-06-01

Cysteine-rich protein 61 (Cyr61)/CCN1 is a product of an immediate early gene and functions in mediating cell adhesion and inducing cell migration. We previously showed that increased production of Cyr61 by fibroblast-like synoviocytes (FLS) in rheumatoid arthritis (RA) promotes FLS proliferation and participates in RA pathogenesis with the IL-17-dependent pathway. However, whether Cyr61 in turn regulates Th17 cell differentiation and further enhances inflammation of RA remained unknown. In the current study, we explored the potential role of Cyr61 as a proinflammatory factor in RA pathogenesis. We found that Cyr61 treatment dramatically induced IL-6 production in FLS isolated from RA patients. Moreover, IL-6 production was attenuated by Cyr61 knockdown in FLS. Mechanistically, we showed that Cyr61 activated IL-6 production via the αvβ5/Akt/NF-κB signaling pathway. Further, using a coculture system consisting of purified CD4(+) T cells and RA FLS, we found that RA FLS stimulated Th17 differentiation, and the pro-Th17 differentiation effect of RA FLS can be attenuated or stimulated by Cyr61 RNA interference or addition of exogenous Cyr61, respectively. Finally, using the collagen-induced arthritis animal model, we showed that treatment with the anti-Cyr61 mAb led to reduction of IL-6 levels, decrease of Th17 response, and attenuation of inflammation and disease progression in vivo. Taken together, our results reveal a novel role of Cyr61 in promoting Th17 development in RA via upregulation of IL-6 production by FLS, thus adding a new layer into the functional interplay between FLS and Th17 in RA pathogenesis. Our study also suggests that targeting of Cyr61 may represent a novel strategy in RA treatment.

Attracted to power: challenge/threat and promotion/prevention focus differentially predict the attractiveness of group power

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Scholl, Annika; Sassenrath, Claudia; Sassenberg, Kai

2015-01-01

Depending on their motivation, individuals prefer different group contexts for social interactions. The present research sought to provide more insight into this relationship. More specifically, we tested how challenge/threat and a promotion/prevention focus predict attraction to groups with high- or low-power. As such, we examined differential outcomes of threat and prevention focus as well as challenge and promotion focus that have often been regarded as closely related. According to regulatory focus, individuals should prefer groups that they expect to “feel right” for them to join: Low-power groups should be more attractive in a prevention (than a promotion) focus, as these groups suggest security-oriented strategies, which fit a prevention focus. High-power groups should be more attractive in a promotion (rather than a prevention) focus, as these groups are associated with promotion strategies fitting a promotion focus (Sassenberg et al., 2007). In contrast, under threat (vs. challenge), groups that allow individuals to restore their (perceived) lack of control should be preferred: Low-power groups should be less attractive under threat (than challenge) because they provide low resources which threatened individuals already perceive as insufficient and high-power groups might be more attractive under threat (than under challenge), because their high resources allow individuals to restore control. Two experiments (N = 140) supported these predictions. The attractiveness of a group often depends on the motivation to engage in what fits (i.e., prefer a group that feels right in the light of one’s regulatory focus). However, under threat the striving to restore control (i.e., prefer a group allowing them to change the status quo under threat vs. challenge) overrides the fit effect, which may in turn guide individuals’ behavior in social interactions. PMID:25904887

Essential and Unexpected Role of YY1 to Promote Mesodermal Cardiac Differentiation

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Gregoire, Serge; Karra, Ravi; Passer, Derek; Deutsch, Marcus-Andre; Krane, Markus; Feistritzer, Rebecca; Sturzu, Anthony; Domian, Ibrahim; Saga, Yumiko; Wu, Sean M.

2013-01-01

Rational Cardiogenesis is regulated by a complex interplay between transcription factors. However, little is known about how these interactions regulate the transition from mesodermal precursors to cardiac progenitor cells (CPCs). Objective To identify novel regulators of mesodermal cardiac lineage commitment. Methods and Results We performed a bioinformatic-based transcription factor binding site analysis on upstream promoter regions of genes that are enriched in embryonic stem cell (ESC)-derived CPCs. From 32 candidate transcription factors screened, we found that YY1, a repressor of sarcomeric gene expression, is present in CPCs in vivo. Interestingly, we uncovered the ability of YY1 to transcriptionally activate Nkx2.5, a key marker of early cardiogenic commitment. YY1 regulates Nkx2.5 expression via a 2.1 kb cardiac-specific enhancer as demonstrated by in vitro luciferase-based assays and in vivo chromatin immunoprecipitation (ChIP) and genome-wide sequencing analysis. Furthermore, the ability of YY1 to activate Nkx2.5 expression depends on its cooperative interaction with Gata4 at a nearby chromatin. Cardiac mesoderm-specific loss-of-function of YY1 resulted in early embryonic lethality. This was corroborated in vitro by ESC-based assays where we show that the overexpression of YY1 enhanced the cardiogenic differentiation of ESCs into CPCs. Conclusion These results demonstrate an essential and unexpected role for YY1 to promote cardiogenesis as a transcriptional activator of Nkx2.5 and other CPC-enriched genes. PMID:23307821

TNF-α-induced NF-κB activation promotes myofibroblast differentiation of LR-MSCs and exacerbates bleomycin-induced pulmonary fibrosis.

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Hou, Jiwei; Ma, Tan; Cao, Honghui; Chen, Yabing; Wang, Cong; Chen, Xiang; Xiang, Zou; Han, Xiaodong

2018-03-01

Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive, and irreversible lung disease of unknown cause. It has been reported that both lung resident mesenchymal stem cells (LR-MSCs) and tumor necrosis factor-α (TNF-α) play important roles in the development of pulmonary fibrosis. However, the underlying connections between LR-MSCs and TNF-α in the pathogenesis of pulmonary fibrosis are still elusive. In this study, we found that the pro-inflammatory cytokine TNF-α and the transcription factor nuclear factor kappa B (NF-κB) p65 subunit were both upregulated in bleomycin-induced fibrotic lung tissue. In addition, we discovered that TNF-α promotes myofibroblast differentiation of LR-MSCs through activating NF-κB signaling. Interestingly, we also found that TNF-α promotes the expression of β-catenin. Moreover, we demonstrated that suppression of the NF-κB signaling could attenuate myofibroblast differentiation of LR-MSCs and bleomycin-induced pulmonary fibrosis which were accompanied with decreased expression of β-catenin. Our data implicates that inhibition of the NF-κB signaling pathway may provide a therapeutic strategy for pulmonary fibrosis, a disease that warrants more effective treatment approaches. © 2017 Wiley Periodicals, Inc.

Human amniotic fluid promotes retinal pigmented epithelial cells' trans-differentiation into rod photoreceptors and retinal ganglion cells.

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Ghaderi, Shima; Soheili, Zahra-Soheila; Ahmadieh, Hamid; Davari, Maliheh; Jahromi, Fatemeh Sanie; Samie, Shahram; Rezaie-Kanavi, Mozhgan; Pakravesh, Jalil; Deezagi, Abdolkhalegh

2011-09-01

To evaluate the effect of human amniotic fluid (HAF) on retinal pigmented epithelial cells growth and trans-differentiation into retinal neurons, retinal pigmented epithelium (RPE) cells were isolated from neonatal human cadaver eye globes and cultured in Dulbecco's modified Eagle's medium-F12 supplemented with 10% fetal bovine serum (FBS). Confluent monolayer cultures were trypsinized and passaged using FBS-containing or HAF-containing media. Amniotic fluid samples were received from pregnant women in the first trimester of gestation. Cell proliferation and death enzyme-linked immunosorbent assays were performed to assess the effect of HAF on RPE cell growth. Trans-differentiation into rod photoreceptors and retinal ganglion cells was also studied using immunocytochemistry and real-time polymerase chain reaction techniques. Primary cultures of RPE cells were successfully established under FBS-containing or HAF-containing media leading to rapid cell growth and proliferation. When RPE cells were moved to in vitro culture system, they began to lose their differentiation markers such as pigmentation and RPE65 marker and trans-differentiated neural-like cells followed by spheroid colonies pertaining to stem/progenitor cells were morphologically detected. Immunocytochemistry (ICC) analysis of HAF-treated cultures showed a considerable expression of Rhodopsin gene (30% Rhodopsin-positive cells) indicating trans-differentiation of RPE cells to rod photoreceptors. Real-time polymerase chain reaction revealed an HAF-dose-dependant expression of Thy-1 gene (RGC marker) and significant promoting effect of HAF on RGCs generation. The data presented here suggest that HAF possesses invaluable stimulatory effect on RPE cells growth and trans-differentiation into retinal neurons. It can be regarded as a newly introduced enriched supplement in serum-free kinds of media used in neuro-retinal regeneration studies.

Hypoxia-inducible factor 1-mediated human GATA1 induction promotes erythroid differentiation under hypoxic conditions.

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Zhang, Feng-Lin; Shen, Guo-Min; Liu, Xiao-Ling; Wang, Fang; Zhao, Ying-Ze; Zhang, Jun-Wu

2012-08-01

Hypoxia-inducible factor promotes erythropoiesis through coordinated cell type-specific hypoxia responses. GATA1 is essential to normal erythropoiesis and plays a crucial role in erythroid differentiation. In this study, we show that hypoxia-induced GATA1 expression is mediated by HIF1 in erythroid cells. Under hypoxic conditions, significantly increased GATA1 mRNA and protein levels were detected in K562 cells and erythroid induction cultures of CD34(+) haematopoietic stem/progenitor cells. Enforced HIF1α expression increased GATA1 expression, while HIF1α knockdown by RNA interference decreased GATA1 expression. In silico analysis revealed one potential hypoxia response element (HRE). The results from reporter gene and mutation analysis suggested that this element is necessary for hypoxic response. Chromatin immunoprecipitation (ChIP)-PCR showed that the putative HRE was recognized and bound by HIF1 in vivo. These results demonstrate that the up-regulation of GATA1 during hypoxia is directly mediated by HIF1.The mRNA expression of some erythroid differentiation markers was increased under hypoxic conditions, but decreased with RNA interference of HIF1α or GATA1. Flow cytometry analysis also indicated that hypoxia, desferrioxamine or CoCl(2) induced expression of erythroid surface markers CD71 and CD235a, while expression repression of HIF1α or GATA1 by RNA interference led to a decreased expression of CD235a. These results suggested that HIF1-mediated GATA1 up-regulation promotes erythropoiesis in order to satisfy the needs of an organism under hypoxic conditions. © 2011 The Authors Journal of Cellular and Molecular Medicine © 2011 Foundation for Cellular and Molecular Medicine/Blackwell Publishing Ltd.

Class A scavenger receptor promotes osteoclast differentiation via the enhanced expression of receptor activator of NF-{kappa}B (RANK)

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Takemura, Kenichi [Department of Cell Pathology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1 Honjo, Kumamoto 860-8556 (Japan); Department of Orthopaedic and Neuro-Musculoskeletal Surgery, Graduate School of Medical Sciences, Kumamoto University, Kumamoto (Japan); Sakashita, Naomi; Fujiwara, Yukio; Komohara, Yoshihiro; Lei, XiaoFeng; Ohnishi, Koji [Department of Cell Pathology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1 Honjo, Kumamoto 860-8556 (Japan); Suzuki, Hiroshi [National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Hokkaido (Japan); Kodama, Tatsuhiko [Department of Molecular Biology and Medicine, Research Center for Advanced Science and Technology, The University of Tokyo, Tokyo (Japan); Mizuta, Hiroshi [Department of Orthopaedic and Neuro-Musculoskeletal Surgery, Graduate School of Medical Sciences, Kumamoto University, Kumamoto (Japan); Takeya, Motohiro, E-mail: takeya@kumamoto-u.ac.jp [Department of Cell Pathology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1 Honjo, Kumamoto 860-8556 (Japan)

2010-01-22

Osteoclasts originate from bone marrow monocyte/macrophage lineage cells, and their differentiation depends on macrophage colony-stimulating factor (M-CSF) and receptor activator nuclear factor kappa B (RANK) ligand. Class A scavenger receptor (SR-A) is one of the principal functional molecules of macrophages, and its level of expression declines during osteoclast differentiation. To investigate the role of SR-A in osteoclastogenesis, we examined pathological changes in femoral bone and the expression levels of osteoclastogenesis-related molecules in SR-A{sup -/-} mice. The femoral osseous density of SR-A{sup -/-} mice was higher than that of SR-A{sup +/+} mice, and the number of multinucleated osteoclasts was significantly decreased. An in vitro differentiation assay revealed that the differentiation of multinucleated osteoclasts from bone marrow-derived progenitor cells is impaired in SR-A{sup -/-} mice. Elimination of SR-A did not alter the expression level of the M-CSF receptor, c-fms; however, the expression levels of RANK and RANK-related osteoclast-differentiation molecules such as nuclear factor of activated T-cells, cytoplasmic, calcineurin-dependent 1 (NFATc1) and microphthalmia-associated transcription factor (MITF) significantly decreased. Furthermore, acetylated low-density lipoprotein (AcLDL), an SR-A ligand, significantly increased the expression level of RANK and MITF during osteoclast differentiation. These data indicate that SR-A promotes osteoclastogenesis via augmentation of the expression level of RANK and its related molecules.

Receptor-interacting Protein 140 Overexpression Promotes Neuro-2a Neuronal Differentiation by ERK1/2 Signaling

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Xiao Feng

2015-01-01

inhibited by the ERK1/2-specific inhibitor U0126. Conclusions: RIP140 overexpression promotes N2a cell neuronal differentiation by activating the ERK1/2 pathway.

MAT2B promotes adipogenesis by modulating SAMe levels and activating AKT/ERK pathway during porcine intramuscular preadipocyte differentiation

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Zhao, Cunzhen; Chen, Xiaochang; Wu, Wenjing; Wang, Wusu; Pang, Weijun; Yang, Gongshe, E-mail: gsyang999@hotmail.com

2016-05-15

Intramuscular fat (IMF) has been demonstrated as one of the crucial factors of livestock meat quality. The MAT2B protein with MAT2α catalyzes the formation of methyl donor S- adenosylmethionine (SAMe) to mediate cell metabolism including proliferation and apoptosis. However, the regulatory effect of MAT2B on IMF deposition is still unclear. In this study, the effect of MAT2B on adipogenesis and its potential mechanism during porcine intramuscular preadipocyte differentiation was studied. The results showed that overexpression of MAT2B promoted adipogenesis and significantly up-regulated the mRNA and protein levels of adipogenic marker genes including FASN, PPARγ and aP2, consistently, knockdown of MAT2B inhibited lipid accumulation and down-regulated the mRNA and protein levels of the above genes. Furthermore, flow cytometry and EdU-labeling assay indicated that MAT2B regulate adipogenesis was partly due to influence intracellular SAMe levels and further affect cell clonal expansion. Also, increased expression of MAT2B activated the phosphorylations of AKT and ERK1/2, whereas knockdown of MAT2B blocked AKT signaling and repressed the phosphorylation of ERK1/2. Moreover, the inhibitory effect of LY294002 (a specific PI3K inhibitor) on the activities of AKT and ERK1/2 was partially recovered by overexpression of MAT2B in porcine intramuscular adipocytes. Finally, Co-IP experiments showed that MAT2B can directly interact with AKT. Taken together, our findings suggested that MAT2B acted as a positive regulator through modifying SAMe levels as well as activating AKT/ERK signaling pathway to promote porcine intramuscular adipocyte differentiation. - Highlights: • MAT2B up-regulates the expression of adipogenic marker genes and promotes porcine intramuscular preadipocyte differentiation. • MAT2B influences intracellular SAMe levels and further affects cell clonal expansion. • MAT2B interacts with AKT and activates AKT/ERK signaling pathway.

Cysticerci Drive Dendritic Cells to Promote In Vitro and In Vivo Tregs Differentiation

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Laura Adalid-Peralta

2013-01-01

Full Text Available Regulatory T cells (Tregs play a crucial role in immune homeostasis. Treg induction is a strategy that parasites have evolved to modulate the host’s inflammatory environment, facilitating their establishment and permanence. In human Taenia solium neurocysticercosis (NC, the concurrence of increased peripheral and central Treg levels and their capacity to inhibit T cell activation and proliferation support their role in controlling neuroinflammation. This study is aimed at identifing possible mechanisms of Treg induction in human NC. Monocyte-derived dendritic cells (DC from healthy human donors, cocultivated with autologous CD4+ naïve cells either in the presence or absence of cysticerci, promoted CD25highFoxp3+ Treg differentiation. An increased Treg induction was observed when cysticerci were present. Moreover, an augmentation of suppressive-related molecules (SLAMF1, B7-H1, and CD205 was found in parasite-induced DC differentiation. Increased Tregs and a higher in vivo DC expression of the regulatory molecules SLAMF1 and CD205 in NC patients were also found. SLAMF1 gene was downregulated in NC patients with extraparenchymal cysticerci, exhibiting higher inflammation levels than patients with parenchymal parasites. Our findings suggest that cysticerci may modulate DC to favor a suppressive environment, which may help parasite establishment, minimizing the excessive inflammation, which may lead to tissue damage.

Kynurenine promotes the goblet cell differentiation of HT-29 colon carcinoma cells by modulating Wnt, Notch and AhR signals.

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Park, Joo-Hung; Lee, Jeong-Min; Lee, Eun-Jin; Kim, Da-Jeong; Hwang, Won-Bhin

2018-04-01

Various amino acids regulate cell growth and differentiation. In the present study, we examined the ability of HT-29 cells to differentiate into goblet cells in RPMI and DMEM which are largely different in the amounts of numerous amino acids. Most of the HT-29 cells differentiated into goblet cells downregulating the stem cell marker Lgr5 when cultured in DMEM, but remained undifferentiated in RPMI. The goblet cell differentiation in DMEM was inhibited by 1-methyl-tryptophan (1-MT), an inhibitor of indoleamine 2,3 dioxygenase-1 which is the initial enzyme in tryptophan metabolism along the kynurenine (KN) pathway, whereas tryptophan and KN induced goblet cell differentiation in RPMI. The levels of Notch1 and its activation product Notch intracytoplasmic domain in HT-29 cells were lower in DMEM than those in RPMI and were increased by 1-MT in both media. HT-29 cells grown in both media expressed β-catenin at the same level on day 2 when goblet cell differentiation was not observed. β-catenin expression, which was increased by 1-MT in both media, was decreased by KN. DMEM reduced Hes1 expression while enhancing Hath1 expression. Finally, aryl hydrocarbon receptor (AhR) activation moderately induced goblet cell differentiation. Our results suggest that KN promotes goblet cell differentiation by regulating Wnt, Notch, and AhR signals and expression of Hes1 and Hath1.

Apolipoprotein E promotes lipid accumulation and differentiation in human adipocytes

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Lasrich, Dorothee; Bartelt, Alexander [Department of Biochemistry and Molecular Cell Biology, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg (Germany); Grewal, Thomas, E-mail: thomas.grewal@sydney.edu.au [Faculty of Pharmacy A15, The University of Sydney, Sydney, NSW 2006 (Australia); Heeren, Joerg, E-mail: heeren@uke.de [Department of Biochemistry and Molecular Cell Biology, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg (Germany)

2015-09-10

Several studies in mice indicate a role for apolipoprotein E (APOE) in lipid accumulation and adipogenic differentiation in adipose tissue. However, little is yet known if APOE functions in a similar manner in human adipocytes. This prompted us to compare lipid loading and expression of adipocyte differentiation markers in APOE-deficient and control adipocytes using the differentiated human mesenchymal stem cell line hMSC-Tert as well as primary human and mouse adipocytes as model systems. Differentiated hMSC-Tert were stably transduced with or without siRNA targeting APOE while murine adipocytes were isolated from wild type and Apoe knockout mice. Human APOE knockdown hMSC-Tert adipocytes accumulated markedly less triglycerides compared to control cells. This correlated with strongly decreased gene expression levels of adipocyte markers such as adiponectin (ADIPOQ) and fatty acid binding protein 4 (FABP4) as well as the key transcription factor driving adipocyte differentiation, peroxisome proliferator activator receptor gamma (PPARG), in particular the PPARG2 isoform. Similarly, differentiation of murine Apoe-deficient adipocytes was characterized by reduced gene expression of Adipoq, Fabp4 and Pparg. Interestingly, incubation of APOE-deficient hMSC-Tert adipocytes with conditioned media from APOE3-overexpressing adipocytes or APOE-containing Very Low Density Lipoprotein (VLDL) partially restored triglyceride accumulation, but were unable to induce adipocyte differentiation, as judged by expression of adipocyte markers. Taken together, depletion of endogenous APOE in human adipocytes severely impairs lipid accumulation, which is associated with an inability to initiate differentiation. - Highlights: • Immortalized human mesenchymal stem cells were used to study adipocyte development. • Knockdown of endogenous APOE lead to impaired lipid accumulation and adipogenesis. • APOE supplementation partially restored lipid accumulation but not differentiation. �

Promoted neuronal differentiation after activation of alpha4/beta2 nicotinic acetylcholine receptors in undifferentiated neural progenitors.

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Takeshi Takarada

Full Text Available BACKGROUND: Neural progenitor is a generic term used for undifferentiated cell populations of neural stem, neuronal progenitor and glial progenitor cells with abilities for proliferation and differentiation. We have shown functional expression of ionotropic N-methyl-D-aspartate (NMDA and gamma-aminobutyrate type-A receptors endowed to positively and negatively regulate subsequent neuronal differentiation in undifferentiated neural progenitors, respectively. In this study, we attempted to evaluate the possible functional expression of nicotinic acetylcholine receptor (nAChR by undifferentiated neural progenitors prepared from neocortex of embryonic rodent brains. METHODOLOGY/PRINCIPAL FINDINGS: Reverse transcription polymerase chain reaction analysis revealed mRNA expression of particular nAChR subunits in undifferentiated rat and mouse progenitors prepared before and after the culture with epidermal growth factor under floating conditions. Sustained exposure to nicotine significantly inhibited the formation of neurospheres composed of clustered proliferating cells and 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide reduction activity at a concentration range of 1 µM to 1 mM without affecting cell survival. In these rodent progenitors previously exposed to nicotine, marked promotion was invariably seen for subsequent differentiation into cells immunoreactive for a neuronal marker protein following the culture of dispersed cells under adherent conditions. Both effects of nicotine were significantly prevented by the heteromeric α4β2 nAChR subtype antagonists dihydro-β-erythroidine and 4-(5-ethoxy-3-pyridinyl-N-methyl-(3E-3-buten-1-amine, but not by the homomeric α7 nAChR subtype antagonist methyllycaconitine, in murine progenitors. Sustained exposure to nicotine preferentially increased the expression of Math1 among different basic helix-loop-helix proneural genes examined. In undifferentiated progenitors from embryonic mice

An Alu-like RNA promotes cell differentiation and reduces malignancy of human neuroblastoma cells.

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Castelnuovo, Manuele; Massone, Sara; Tasso, Roberta; Fiorino, Gloria; Gatti, Monica; Robello, Mauro; Gatta, Elena; Berger, Audrey; Strub, Katharina; Florio, Tullio; Dieci, Giorgio; Cancedda, Ranieri; Pagano, Aldo

2010-10-01

Neuroblastoma (NB) is a pediatric cancer characterized by remarkable cell heterogeneity within the tumor nodules. Here, we demonstrate that the synthesis of a pol III-transcribed noncoding (nc) RNA (NDM29) strongly restricts NB development by promoting cell differentiation, a drop of malignancy processes, and a dramatic reduction of the tumor initiating cell (TIC) fraction in the NB cell population. Notably, the overexpression of NDM29 also confers to malignant NB cells an unpredicted susceptibility to the effects of antiblastic drugs used in NB therapy. Altogether, these results suggest the induction of NDM29 expression as possible treatment to increase cancer cells vulnerability to therapeutics and the measure of its synthesis in NB explants as prognostic factor of this cancer type.

Differential SLC1A2 Promoter Methylation in Bipolar Disorder With or Without Addiction

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Yun-Fang Jia

2017-07-01

Full Text Available While downregulation of excitatory amino acid transporter 2 (EAAT2, the main transporter removing glutamate from the synapse, has been recognized in bipolar disorder (BD, the underlying mechanisms of downregulation have not been elucidated. BD is influenced by environmental factors, which may, via epigenetic modulation of gene expression, differentially affect illness presentation. This study thus focused on epigenetic DNA methylation regulation of SLC1A2, encoding for EAAT2, in BD with variable environmental influences of addiction. High resolution melting PCR (HRM-PCR and thymine–adenine (TA cloning with sequence analysis were conducted to examine methylation of the promoter region of the SLC1A2. DNA was isolated from blood samples drawn from BD patients (N = 150 with or without addiction to alcohol, nicotine, or food, defined as binge eating, and matched controls (N = 32. In comparison to controls, the SLC1A2 promoter region was hypermethylated in BD without addiction but was hypomethylated in BD with addiction. After adjusting for age and sex, the association of methylation levels with nicotine addiction (p = 0.0009 and binge eating (p = 0.0002 remained significant. Consistent with HRM-PCR, direct sequencing revealed increased methylation in CpG site 6 in BD, but decreased methylation in three CpG sites (6, 48, 156 in BD with alcohol and nicotine addictions. These results suggest that individual point methylation within the SLC1A2 promoter region may be modified by exogenous addiction and may have a potential for developing clinically valuable epigenetic biomarkers for BD diagnosis and monitoring.

Extracellular Matrix Metalloproteinase Inducer (EMMPRIN) promotes lung fibroblast proliferation, survival and differentiation to myofibroblasts.

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Hasaneen, Nadia A; Cao, Jian; Pulkoski-Gross, Ashleigh; Zucker, Stanley; Foda, Hussein D

2016-02-17

Idiopathic pulmonary fibrosis (IPF) is a chronic progressively fatal disease. Extracellular Matrix Metalloproteinase Inducer (EMMPRIN) is a glycosylated transmembrane protein that induces the expression of some matrix metalloproteinase (MMP) in neighboring stromal cells through direct epithelial-stromal interactions. EMMPRIN is highly expressed in type II alveolar epithelial cells at the edges of the fibrotic areas in IPF lung sections. However, the exact role of EMMPRIN in IPF is unknown. To determine if EMMPRIN contributes to lung fibroblast proliferation, resistance to apoptosis, and differentiation to myofibroblasts, normal Human lung fibroblasts (NHLF) transiently transfected with either EMMPRIN/GFP or GFP were treated with TGF- β1 from 0 to 10 ng/ml for 48 h and examined for cell proliferation (thymidine incorporation), apoptosis (FACS analysis and Cell Death Detection ELISA assay), cell migration (Modified Boyden chamber) and differentiation to myofibroblasts using Western blot for α-smooth actin of cell lysates. The effect of EMMPRIN inhibition on NHLF proliferation, apoptosis, migration and differentiation to myofibroblasts after TGF- β1 treatment was examined using EMMPRIN blocking antibody. We examined the mechanism by which EMMPRIN induces its effects on fibroblasts by studying the β-catenin/canonical Wnt signaling pathway using Wnt luciferase reporter assays and Western blot for total and phosphorylated β-catenin. Human lung fibroblasts overexpressing EMMPRIN had a significant increase in cell proliferation and migration compared to control fibroblasts. Furthermore, EMMPRIN promoted lung fibroblasts resistance to apoptosis. Lung fibroblasts overexpressing EMMPRIN showed a significantly increased expression of α- smooth muscle actin, a marker of differentiation to myofibroblasts compared to control cells. TGF-β1 increased the expression of EMMPRIN in lung fibroblasts in a dose-dependent manner. Attenuation of EMMPRIN expression with the use of an

Osthole promotes neuronal differentiation and inhibits apoptosis via Wnt/β-catenin signaling in an Alzheimer's disease model

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Yao, Yingjia [School of Pharmacy, Liaoning University of Traditional Chinese Medicine, Dalian 116600 (China); Gao, Zhong [Department of Interventional Therapy, Dalian Municipal Central Hospital, Dalian 116033 (China); Liang, Wenbo [Medical College of Dalian University, Dalian 116600, Liaoning (China); Kong, Liang; Jiao, Yanan; Li, Shaoheng; Tao, Zhenyu; Yan, Yuhui [School of Pharmacy, Liaoning University of Traditional Chinese Medicine, Dalian 116600 (China); Yang, Jingxian, E-mail: jingxianyang@yahoo.com [School of Pharmacy, Liaoning University of Traditional Chinese Medicine, Dalian 116600 (China)

2015-12-15

Neurogenesis is the process by which neural stem cells (NSCs) proliferate and differentiate into neurons. This is diminished in several neurodegenerative disorders such as Alzheimer's disease (AD), which is characterized by the deposition of amyloid (A)β peptides and neuronal loss. Stimulating NSCs to replace lost neurons is therefore a promising approach for AD treatment. Our previous study demonstrated that osthole modulates NSC proliferation and differentiation, and may reduce Aβ protein expression in nerve cells. Here we investigated the mechanism underlying the effects of osthole on NSCs. We found that osthole enhances NSC proliferation and neuronal differentiation while suppressing apoptosis, effects that were exerted via activation of Wnt/β-catenin signaling. These results provide evidence that osthole can potentially be used as a therapeutic agent in the treatment of AD and other neurodegenerative disorders. - Highlights: • An Alzheimer's disease model was successfully established by transfecting APP gene into neural stem cells in vitro. • Roles of osthole in experimental AD cells were studied. • Osthole promotes proliferation and differentiation into neurons and inhibits accumulation of Aβ{sub 1–42} peptide and apoptosis. • Osthole exerts protection via Wnt/β-catenin signaling pathway.

Osthole promotes neuronal differentiation and inhibits apoptosis via Wnt/β-catenin signaling in an Alzheimer's disease model

International Nuclear Information System (INIS)

Yao, Yingjia; Gao, Zhong; Liang, Wenbo; Kong, Liang; Jiao, Yanan; Li, Shaoheng; Tao, Zhenyu; Yan, Yuhui; Yang, Jingxian

2015-01-01

Neurogenesis is the process by which neural stem cells (NSCs) proliferate and differentiate into neurons. This is diminished in several neurodegenerative disorders such as Alzheimer's disease (AD), which is characterized by the deposition of amyloid (A)β peptides and neuronal loss. Stimulating NSCs to replace lost neurons is therefore a promising approach for AD treatment. Our previous study demonstrated that osthole modulates NSC proliferation and differentiation, and may reduce Aβ protein expression in nerve cells. Here we investigated the mechanism underlying the effects of osthole on NSCs. We found that osthole enhances NSC proliferation and neuronal differentiation while suppressing apoptosis, effects that were exerted via activation of Wnt/β-catenin signaling. These results provide evidence that osthole can potentially be used as a therapeutic agent in the treatment of AD and other neurodegenerative disorders. - Highlights: • An Alzheimer's disease model was successfully established by transfecting APP gene into neural stem cells in vitro. • Roles of osthole in experimental AD cells were studied. • Osthole promotes proliferation and differentiation into neurons and inhibits accumulation of Aβ 1–42 peptide and apoptosis. • Osthole exerts protection via Wnt/β-catenin signaling pathway.

Porous hydroxyapatite and biphasic calcium phosphate ceramics promote ectopic osteoblast differentiation from mesenchymal stem cells

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Zhang Lingli; Fan Hongsong; Zhang Xingdong [National Engineering Research Center for Biomaterials, Sichuan University, Chengdu, Sichuan 610064 (China); Hanagata, Nobutaka; Ikoma, Toshiyuki [Biomaterials Center, National Institute for Materials Science, Tsukuba, Ibaraki 305-0047 (Japan); Maeda, Megumi; Minowa, Takashi, E-mail: HANAGATA.Nobutaka@nims.go.j [Nanotechnology Innovation Center, National Institute for Materials Science, Tsukuba, Ibaraki 305-0047 (Japan)

2009-04-15

Because calcium phosphate (Ca-P) ceramics have been used as bone substitutes, it is necessary to investigate what effects the ceramics have on osteoblast maturation. We prepared three types of Ca-P ceramics with different Ca-P ratios, i.e. hydroxyapatite (HA), beta-tricalcium phosphate ({beta}-TCP), and biphasic calcium phosphate (BCP) ceramics with dense-smooth and porous structures. Comprehensive gene expression microarray analysis of mouse osteoblast-like cells cultured on these ceramics revealed that porous Ca-P ceramics considerably affected the gene expression profiles, having a higher potential for osteoblast maturation. In the in vivo study that followed, porous Ca-P ceramics were implanted into rat skeletal muscle. Sixteen weeks after the implantation, more alkaline-phosphatase-positive cells were observed in the pores of hydroxyapatite and BCP, and the expression of the osteocalcin gene (an osteoblast-specific marker) in tissue grown in pores was also higher in hydroxyapatite and BCP than in {beta}-TCP. In the pores of any Ca-P ceramics, 16 weeks after the implantation, we detected the expressions of marker genes of the early differentiation stage of chondrocytes and the complete differentiation stage of adipocytes, which originate from mesenchymal stem cells, as well as osteoblasts. These marker gene expressions were not observed in the muscle tissue surrounding the implanted Ca-P ceramics. These observations indicate that porous hydroxyapatite and BCP had a greater potential for promoting the differentiation of mesenchymal stem cells into osteoblasts than {beta}-TCP.

Silk-Fibroin and Graphene Oxide Composites Promote Human Periodontal Ligament Stem Cell Spontaneous Differentiation into Osteo/Cementoblast-Like Cells.

Science.gov (United States)

Vera-Sánchez, Mar; Aznar-Cervantes, Salvador; Jover, Eva; García-Bernal, David; Oñate-Sánchez, Ricardo E; Hernández-Romero, Diana; Moraleda, Jose M; Collado-González, Mar; Rodríguez-Lozano, Francisco Javier; Cenis, Jose Luis

2016-11-15

Graphene represents one of the most interesting additions to the tissue engineering toolbox. Novel graphene-based composites are required to improve the beneficial graphene properties in terms of tridimensional polymeric structure, conferring a higher mechanical strength and favoring the differentiation of human mesenchymal stem cells. Here, we have demonstrated in a wide range of composite combinations, the successful use of graphene and silk-fibroin constructs for future bioengineering applications in the field of clinical regenerative dentistry using human periodontal ligament stem cells. Our results provide exciting new data for the development of suitable scaffolds that allow good cell engrafting, preservation of cell viability and proliferation, promotion of spontaneous osteoblastic differentiation, and importantly, stimulation of a higher cementum physiological synthesis than using other different available biomaterials.

Endothelium trans differentiated from Wharton's jelly mesenchymal cells promote tissue regeneration: potential role of soluble pro-angiogenic factors.

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Aguilera, Valeria; Briceño, Luis; Contreras, Hector; Lamperti, Liliana; Sepúlveda, Esperanza; Díaz-Perez, Francisca; León, Marcelo; Veas, Carlos; Maura, Rafael; Toledo, Jorge Roberto; Fernández, Paulina; Covarrubias, Ambart; Zuñiga, Felipe Andrés; Radojkovic, Claudia; Escudero, Carlos; Aguayo, Claudio

2014-01-01

Mesenchymal stem cells have a high capacity for trans-differentiation toward many adult cell types, including endothelial cells. Feto-placental tissue, such as Wharton's jelly is a potential source of mesenchymal stem cells with low immunogenic capacity; make them an excellent source of progenitor cells with a potential use for tissue repair. We evaluated whether administration of endothelial cells derived from mesenchymal stem cells isolated from Wharton's jelly (hWMSCs) can accelerate tissue repair in vivo. Mesenchymal stem cells were isolated from human Wharton's jelly by digestion with collagenase type I. Endothelial trans-differentiation was induced for 14 (hWMSC-End14d) and 30 (hWMSC-End30d) days. Cell phenotyping was performed using mesenchymal (CD90, CD73, CD105) and endothelial (Tie-2, KDR, eNOS, ICAM-1) markers. Endothelial trans-differentiation was demonstrated by the expression of endothelial markers and their ability to synthesize nitric oxide (NO). hWMSCs can be differentiated into adipocytes, osteocytes, chondrocytes and endothelial cells. Moreover, these cells show high expression of CD73, CD90 and CD105 but low expression of endothelial markers prior to differentiation. hWMSCs-End express high levels of endothelial markers at 14 and 30 days of culture, and also they can synthesize NO. Injection of hWMSC-End30d in a mouse model of skin injury significantly accelerated wound healing compared with animals injected with undifferentiated hWMSC or injected with vehicle alone. These effects were also observed in animals that received conditioned media from hWMSC-End30d cultures. These results demonstrate that mesenchymal stem cells isolated from Wharton's jelly can be cultured in vitro and trans-differentiated into endothelial cells. Differentiated hWMSC-End may promote neovascularization and tissue repair in vivo through the secretion of soluble pro-angiogenic factors.

The Differentiation and Promotion of Students' Rights in Portugal

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Veiga, Feliciano; Garcia, Fernando; Neto, Felix; Almeida, Leandro

2009-01-01

This investigation includes a differential study (Study 1) and a quasi-experimental research (Study 2). In Study 1, the objective was to establish to what extent students' rights existed and analyse the differentiation between students' rights with Portuguese and immigrant mothers, throughout school years. The sample consisted of 537 students with…

Follicular B Cells Promote Atherosclerosis via T Cell-Mediated Differentiation Into Plasma Cells and Secreting Pathogenic Immunoglobulin G.

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Tay, Christopher; Liu, Yu-Han; Kanellakis, Peter; Kallies, Axel; Li, Yi; Cao, Anh; Hosseini, Hamid; Tipping, Peter; Toh, Ban-Hock; Bobik, Alex; Kyaw, Tin

2018-05-01

B cells promote or protect development of atherosclerosis. In this study, we examined the role of MHCII (major histocompatibility II), CD40 (cluster of differentiation 40), and Blimp-1 (B-lymphocyte-induced maturation protein) expression by follicular B (FO B) cells in development of atherosclerosis together with the effects of IgG purified from atherosclerotic mice. Using mixed chimeric Ldlr -/- mice whose B cells are deficient in MHCII or CD40, we demonstrate that these molecules are critical for the proatherogenic actions of FO B cells. During development of atherosclerosis, these deficiencies affected T-B cell interactions, germinal center B cells, plasma cells, and IgG. As FO B cells differentiating into plasma cells require Blimp-1, we also assessed its role in the development of atherosclerosis. Blimp-1-deficient B cells greatly attenuated atherosclerosis and immunoglobulin-including IgG production, preventing IgG accumulation in atherosclerotic lesions; Blimp-1 deletion also attenuated lesion proinflammatory cytokines, apoptotic cell numbers, and necrotic core. To determine the importance of IgG for atherosclerosis, we purified IgG from atherosclerotic mice. Their transfer but not IgG from nonatherosclerotic mice into Ldlr -/- mice whose B cells are Blimp-1-deficient increased atherosclerosis; transfer was associated with IgG accumulating in atherosclerotic lesions, increased lesion inflammatory cytokines, apoptotic cell numbers, and necrotic core size. The mechanism by which FO B cells promote atherosclerosis is highly dependent on their expression of MHCII, CD40, and Blimp-1. FO B cell differentiation into IgG-producing plasma cells also is critical for their proatherogenic actions. Targeting B-T cell interactions and pathogenic IgG may provide novel therapeutic strategies to prevent atherosclerosis and its adverse cardiovascular complications. © 2018 American Heart Association, Inc.

Peptide-laden mesoporous silica nanoparticles with promoted bioactivity and osteo-differentiation ability for bone tissue engineering.

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Luo, Zuyuan; Deng, Yi; Zhang, Ranran; Wang, Mengke; Bai, Yanjie; Zhao, Qiang; Lyu, Yalin; Wei, Jie; Wei, Shicheng

2015-07-01

Combination of mesoporous silica materials and bioactive factors is a promising niche-mimetic solution as a hybrid bone substitution for bone tissue engineering. In this work, we have synthesized biocompatible silica-based nanoparticles with abundant mesoporous structure, and incorporated bone-forming peptide (BFP) derived from bone morphogenetic protein-7 (BMP-7) into the mesoporous silica nanoparticles (MSNs) to obtain a slow-release system for osteogenic factor delivery. The chemical characterization demonstrates that the small osteogenic peptide is encapsulated in the mesoporous successfully, and the nitrogen adsorption-desorption isotherms suggest that the peptide encapsulation has no influence on mesoporous structure of MSNs. In the cell experiment, the peptide-laden MSNs (p-MSNs) show higher MG-63 cell proliferation, spreading and alkaline phosphatase (ALP) activity than the bare MSNs, indicating good in vitro cytocompatibility. Simultaneously, the osteogenesis-related proteins expression and calcium mineral deposition disclose enhanced osteo-differentiation of human mesenchymal stem cells (hMSCs) under the stimulation of the p-MSNs, confirming that BFP released from MSNs could significantly promote the osteogenic differentiation of hMSCs, especially at 500μg/mL of p-MSNs concentration. The peptide-modified MSNs with better bioactivity and osteogenic differentiation make it a potential candidate as bioactive material for bone repairing, bone regeneration, and bio-implant coating applications. Copyright © 2015 Elsevier B.V. All rights reserved.

The Effect of Agmatine on Expression of IL-1β and TLX Which Promotes Neuronal Differentiation in Lipopolysaccharide-Treated Neural Progenitors.

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Song, Juhyun; Kumar, Bokara Kiran; Kang, Somang; Park, Kyung Ah; Lee, Won Taek; Lee, Jong Eun

2013-12-01

Differentiation of neural progenitor cells (NPCs) is important for protecting neural cells and brain tissue during inflammation. Interleukin-1 beta (IL-1β) is the most common pro- inflammatory cytokine in brain inflammation, and increased IL-1β levels can decrease the proliferation of NPCs. We aimed to investigate whether agmatine (Agm), a primary polyamine that protects neural cells, could trigger differentiation of NPCs by activating IL-1β in vitro. The cortex of ICR mouse embryos (E14) was dissociated to culture NPCs. NPCs were stimulated by lipopolysaccharide (LPS). After 6 days, protein expression of stem cell markers and differentiation signal factors was confirmed by using western blot analysis. Also, immunocytochemistry was used to confirm the cell fate. Agm treatment activated NPC differentiation significantly more than in the control group, which was evident by the increased expression of a neuronal marker, MAP2, in the LPS-induced, Agm-treated group. Differentiation of LPS-induced, Agm-treated NPCs was regulated by the MAPK pathway and is thought to be related to IL-1β activation and decreased expression of TLX, a transcription factor that regulates NPC differentiation. Our results reveal that Agm can promote NPC differentiation to neural stem cells by modulating IL-1β expression under inflammatory condition, and they suggest that Agm may be a novel therapeutic strategy for neuroinflammatory diseases.

Kaempferol-immobilized titanium dioxide promotes formation of new bone: effects of loading methods on bone marrow stromal cell differentiation in vivo and in vitro.

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Tsuchiya, Shuhei; Sugimoto, Keisuke; Kamio, Hisanobu; Okabe, Kazuto; Kuroda, Kensuke; Okido, Masazumi; Hibi, Hideharu

2018-01-01

Surface modification of titanium dioxide (TiO 2 ) implants promotes bone formation and shortens the osseointegration period. Kaempferol is a flavonoid that has the capacity to promote osteogenic differentiation in bone marrow stromal cells. The aim of this study was to promote bone formation around kaempferol immobilized on TiO 2 implants. There were four experimental groups. Alkali-treated TiO 2 samples (implants and discs) were used as a control and immersed in Dulbecco's phosphate-buffered saline (DPBS) (Al-Ti). For the coprecipitation sample (Al-cK), the control samples were immersed in DPBS containing 50 µg kaempferol/100% ethanol. For the adsorption sample (Al-aK), 50 µg kaempferol/100% ethanol was dropped onto control samples. The surface topography of the TiO 2 implants was observed by scanning electron microscopy with energy-dispersive X-ray spectroscopy, and a release assay was performed. For in vitro experiments, rat bone marrow stromal cells (rBMSCs) were cultured on each of the TiO 2 samples to analyze cell proliferation, alkaline phosphatase activity, calcium deposition, and osteogenic differentiation. For in vivo experiments, TiO 2 implants placed on rat femur bones were analyzed for bone-implant contact by histological methods. Kaempferol was detected on the surface of Al-cK and Al-aK. The results of the in vitro study showed that rBMSCs cultured on Al-cK and Al-aK promoted alkaline phosphatase activity, calcium deposition, and osteogenic differentiation. The in vivo histological analysis revealed that Al-cK and Al-aK stimulated new bone formation around implants. TiO 2 implant-immobilized kaempferol may be an effective tool for bone regeneration around dental implants.

ET-1 Promotes Differentiation of Periodontal Ligament Stem Cells into Osteoblasts through ETR, MAPK, and Wnt/β-Catenin Signaling Pathways under Inflammatory Microenvironment

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Liang, Li; Zhou, Wei; Yang, Nan; Yu, Jifeng; Liu, Hongchen

2016-01-01

Periodontitis is a kind of chronic inflammatory disease that affects the tooth-supporting tissues. ET-1 is related to periodontitis and involved in the regulation of cytokines, but the mechanisms remain unclear. The aim of this study is to investigate how ET-1 affects proinflammatory cytokine expression and differentiation in human periodontal ligament stem cells (PDLSCs). PDLSCs were isolated from the periodontal ligament tissues of periodontitis patients and then treated with ET-1 (1, 10, or 100 nM) for 12 h, 24 h, or 72 h. The osteogenic potential of PDLSCs was tested using ALP staining. TNF-α, IL-1β, and IL-6 levels were evaluated by ELISA and western blot. Runx2, OCN, and COL1 mRNA and western levels were detected by RT-PCR and western blot, respectively. To examine the signaling pathways and molecular mechanisms involved in ET-1-mediated cytokine expression and osteogenic differentiation, ETR pathway, MAPKs pathway, Wnt/β-catenin pathway, and Wnt/Ca2+ pathway were detected by RT-PCR and western blot, respectively. ET-1 promoted differentiation of PDLSCs into osteoblasts by increasing secretion of TNF-α, IL-1β, and IL-6 in a dose- and time-dependent manner. ET-1 also increased expression of Runx2, OCN, and COL1. ET-1 promotes differentiation of PDLSCs into osteoblasts through ETR, MAPK, and Wnt/β-catenin signaling pathways under inflammatory microenvironment. PMID:26884650

ET-1 Promotes Differentiation of Periodontal Ligament Stem Cells into Osteoblasts through ETR, MAPK, and Wnt/β-Catenin Signaling Pathways under Inflammatory Microenvironment

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Li Liang

2016-01-01

Full Text Available Periodontitis is a kind of chronic inflammatory disease that affects the tooth-supporting tissues. ET-1 is related to periodontitis and involved in the regulation of cytokines, but the mechanisms remain unclear. The aim of this study is to investigate how ET-1 affects proinflammatory cytokine expression and differentiation in human periodontal ligament stem cells (PDLSCs. PDLSCs were isolated from the periodontal ligament tissues of periodontitis patients and then treated with ET-1 (1, 10, or 100 nM for 12 h, 24 h, or 72 h. The osteogenic potential of PDLSCs was tested using ALP staining. TNF-α, IL-1β, and IL-6 levels were evaluated by ELISA and western blot. Runx2, OCN, and COL1 mRNA and western levels were detected by RT-PCR and western blot, respectively. To examine the signaling pathways and molecular mechanisms involved in ET-1-mediated cytokine expression and osteogenic differentiation, ETR pathway, MAPKs pathway, Wnt/β-catenin pathway, and Wnt/Ca2+ pathway were detected by RT-PCR and western blot, respectively. ET-1 promoted differentiation of PDLSCs into osteoblasts by increasing secretion of TNF-α, IL-1β, and IL-6 in a dose- and time-dependent manner. ET-1 also increased expression of Runx2, OCN, and COL1. ET-1 promotes differentiation of PDLSCs into osteoblasts through ETR, MAPK, and Wnt/β-catenin signaling pathways under inflammatory microenvironment.

Human Dental Pulp Cells Differentiate toward Neuronal Cells and Promote Neuroregeneration in Adult Organotypic Hippocampal Slices In Vitro.

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Xiao, Li; Ide, Ryoji; Saiki, Chikako; Kumazawa, Yasuo; Okamura, Hisashi

2017-08-11

The adult mammalian central nerve system has fundamental difficulties regarding effective neuroregeneration. The aim of this study is to investigate whether human dental pulp cells (DPCs) can promote neuroregeneration by (i) being differentiated toward neuronal cells and/or (ii) stimulating local neurogenesis in the adult hippocampus. Using immunostaining, we demonstrated that adult human dental pulp contains multipotent DPCs, including STRO-1, CD146 and P75-positive stem cells. DPC-formed spheroids were able to differentiate into neuronal, vascular, osteogenic and cartilaginous lineages under osteogenic induction. However, under neuronal inductive conditions, cells in the DPC-formed spheroids differentiated toward neuronal rather than other lineages. Electrophysiological study showed that these cells consistently exhibit the capacity to produce action potentials, suggesting that they have a functional feature in neuronal cells. We further co-cultivated DPCs with adult mouse hippocampal slices on matrigel in vitro. Immunostaining and presto blue assay showed that DPCs were able to stimulate the growth of neuronal cells (especially neurons) in both the CA1 zone and the edges of the hippocampal slices. Brain-derived neurotrophic factor (BDNF), was expressed in co-cultivated DPCs. In conclusion, our data demonstrated that DPCs are well-suited to differentiate into the neuronal lineage. They are able to stimulate neurogenesis in the adult mouse hippocampus through neurotrophic support in vitro.

UV-activated 7-dehydrocholesterol-coated titanium implants promote differentiation of human umbilical cord mesenchymal stem cells into osteoblasts.

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Satué, María; Ramis, Joana M; Monjo, Marta

2016-01-01

Vitamin D metabolites are essential for bone regeneration and mineral homeostasis. The vitamin D precursor 7-dehydrocholesterol can be used after UV irradiation to locally produce active vitamin D by osteoblastic cells. Furthermore, UV-irradiated 7-dehydrocholesterol is a biocompatible coating for titanium implants with positive effects on osteoblast differentiation. In this study, we examined the impact of titanium implants surfaces coated with UV-irradiated 7-dehydrocholesterol on the osteogenic differentiation of human umbilical cord mesenchymal stem cells. First, the synthesis of cholecalciferol (D3) was achieved through the incubation of the UV-activated 7-dehydrocholesterol coating for 48 h at 23℃. Further, we investigated in vitro the biocompatibility of this coating in human umbilical cord mesenchymal stem cells and its potential to enhance their differentiation towards the osteogenic lineage. Human umbilical cord mesenchymal stem cells cultured onto UV-irradiated 7-dehydrocholesterol-coated titanium implants surfaces, combined with osteogenic supplements, upregulated the gene expression of several osteogenic markers and showed higher alkaline phosphatase activity and calcein blue staining, suggesting increased mineralization. Thus, our results show that the use of UV irradiation on 7-dehydrocholesterol -treated titanium implants surfaces generates a bioactive coating that promotes the osteogenic differentiation of human umbilical cord mesenchymal stem cells, with regenerative potential for improving osseointegration in titanium-based bone anchored implants. © The Author(s) 2015.

Cyclic AMP-Responsive Element-Binding Protein (CREB is Critical in Autoimmunity by Promoting Th17 but Inhibiting Treg Cell Differentiation

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Xiaohu Wang

2017-11-01

Full Text Available The molecular mechanisms that govern differential T cell development into pro-inflammatory Th17 vs. regulatory T (Treg cells remain unclear. Here, we show that selective deletion of CREB in T cells or Th17 cells impaired Th17 cell differentiation in vitro and in vivo, and led to resistance to autoimmune diseases. Mechanistically, CREB, activated by CD3-PKC-ϴ signaling, plays a key role in regulating Th17 cell differentiation, at least in part through directly binding to the Il17-Il17f gene locus. Unexpectedly, although dispensable for FOXP3 expression and for the homeostasis and suppressive function of thymus-derived Treg cells, CREB negatively regulates the survival of TGF-β-induced Treg cells, and deletion of CREB resulted in increased FOXP3+ Treg cells in the intestine and protection in a colitis model. Thus, CREB is critical in autoimmune diseases by promoting Th17 cell and inhibiting de novo Treg cell generation.

Organic cation transporter-mediated ergothioneine uptake in mouse neural progenitor cells suppresses proliferation and promotes differentiation into neurons.

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Takahiro Ishimoto

Full Text Available The aim of the present study is to clarify the functional expression and physiological role in neural progenitor cells (NPCs of carnitine/organic cation transporter OCTN1/SLC22A4, which accepts the naturally occurring food-derived antioxidant ergothioneine (ERGO as a substrate in vivo. Real-time PCR analysis revealed that mRNA expression of OCTN1 was much higher than that of other organic cation transporters in mouse cultured cortical NPCs. Immunocytochemical analysis showed colocalization of OCTN1 with the NPC marker nestin in cultured NPCs and mouse embryonic carcinoma P19 cells differentiated into neural progenitor-like cells (P19-NPCs. These cells exhibited time-dependent [(3H]ERGO uptake. These results demonstrate that OCTN1 is functionally expressed in murine NPCs. Cultured NPCs and P19-NPCs formed neurospheres from clusters of proliferating cells in a culture time-dependent manner. Exposure of cultured NPCs to ERGO or other antioxidants (edaravone and ascorbic acid led to a significant decrease in the area of neurospheres with concomitant elimination of intracellular reactive oxygen species. Transfection of P19-NPCs with small interfering RNA for OCTN1 markedly promoted formation of neurospheres with a concomitant decrease of [(3H]ERGO uptake. On the other hand, exposure of cultured NPCs to ERGO markedly increased the number of cells immunoreactive for the neuronal marker βIII-tubulin, but decreased the number immunoreactive for the astroglial marker glial fibrillary acidic protein (GFAP, with concomitant up-regulation of neuronal differentiation activator gene Math1. Interestingly, edaravone and ascorbic acid did not affect such differentiation of NPCs, in contrast to the case of proliferation. Knockdown of OCTN1 increased the number of cells immunoreactive for GFAP, but decreased the number immunoreactive for βIII-tubulin, with concomitant down-regulation of Math1 in P19-NPCs. Thus, OCTN1-mediated uptake of ERGO in NPCs inhibits

Tailless-like (TLX) protein promotes neuronal differentiation of dermal multipotent stem cells and benefits spinal cord injury in rats.

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Wang, Tao; Ren, Xiaobao; Xiong, Jianqiong; Zhang, Lei; Qu, Jifu; Xu, Wenyue

2011-04-01

Spinal cord injury (SCI) remains a formidable challenge in the clinic. In the current study, we examined the effects of the TLX gene on the proliferation and neuronal differentiation of dermal multipotent stem cells (DMSCs) in vitro and the potential of these cells to improve SCI in rats in vivo. DMSCs were stably transfected with TLX-expressing plasmid (TLX/DMSCs). Cell proliferation was examined using the MTT assay, and neuronal differentiation was characterized by morphological observation combined with immunocytochemical/immunofluorescent staining. The in vivo functions of these cells were evaluated by transplantation into rats with SCI, followed by analysis of hindlimb locomotion and post-mortem histology. Compared to parental DMSCs, TLX/DMSCs showed enhanced proliferation and preferential differentiation into NF200-positive neurons in contrast to GFAP-positive astrocytes. When the undifferentiated cells were transplanted into rats with SCI injury, TLX/DMSCs led to significant improvement in locomotor recovery and healing of SCI, as evidenced by reduction in scar tissues and cavities, increase in continuous nerve fibers/axons and enrichment of NF200-positive neurons on the histological level. In conclusion, TLX promotes the proliferation and neuronal differentiation of DMSCs and thus, may serve as a promising therapy for SCI in the clinic.

Borax-Loaded PLLA for Promotion of Myogenic Differentiation.

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Rico, Patricia; Rodrigo-Navarro, Aleixandre; Salmerón-Sánchez, Manuel

2015-11-01

Boron is an essential metalloid, which plays a key role in plant and animal metabolisms. It has been reported that boron is involved in bone mineralization, has some uses in synthetic chemistry, and its potential has been only recently exploited in medicinal chemistry. However, in the area of tissue engineering, the use of boron is limited to works involving certain bioactive glasses. In this study, we engineer poly(l-lactic acid) (PLLA) substrates with sustained release of boron. Then, we analyze for the first time the uniqueness effects of boron in cell differentiation using murine C2C12 myoblasts and discuss a potential mechanism of action in cooperation with Ca(2+). Our results demonstrate that borax-loaded materials strongly enhance myotube formation at initial steps of myogenesis. Furthermore, we demonstrate that Ca(2+) plays an essential role in combination with borax as chelating or blocking Ca(2+) entry into the cell leads to a detrimental effect on myoblast differentiation observed on borax-loaded materials. This research identifies borax-loaded materials to trigger differentiation mechanisms and it establishes a new tool to engineer microenvironments with applications in regenerative medicine for muscular diseases.

N-Cadherin Upregulation Promotes the Neurogenic Differentiation of Menstrual Blood-Derived Endometrial Stem Cells.

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Liu, Yanli; Yang, Fen; Liang, Shengying; Liu, Qing; Fu, Sulei; Wang, Zhenyu; Yang, Ciqing; Lin, Juntang

2018-01-01

Peripheral nerve injuries are typically caused by either trauma or medical disorders, and recently, stem cell-based therapies have provided a promising treatment approach. Menstrual blood-derived endometrial stem cells (MenSCs) are considered an ideal therapeutic option for peripheral nerve repair due to a noninvasive collection procedure and their high proliferation rate and immunological tolerance. Here, we successfully isolated MenSCs and examined their biological characteristics including their morphology, multipotency, and immunophenotype. Subsequent in vitro studies demonstrated that MenSCs express high levels of neurotrophic factors, such as NT3, NT4, BDNF, and NGF, and are capable of transdifferentiating into glial-like cells under conventional induction conditions. Moreover, upregulation of N-cadherin (N-cad) mRNA and protein expression was observed after neurogenic differentiation. In vivo studies clearly showed that N-cad knockdown via in utero electroporation perturbed the migration and maturation of mouse neural precursor cells (NPCs). Finally, a further transfection assay also confirmed that N-cad upregulation in MenSCs results in the expression of S100. Collectively, our results confirmed the paracrine effect of MenSCs on neuroprotection as well as their potential for transdifferentiation into glial-like cells and demonstrated that N-cad upregulation promotes the neurogenic differentiation of MenSCs, thereby providing support for transgenic MenSC-based therapy for peripheral nerve injury.

Differential Regulation of Telomerase Reverse Transcriptase Promoter Activation and Protein Degradation by Histone Deacetylase Inhibition.

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Qing, Hua; Aono, Jun; Findeisen, Hannes M; Jones, Karrie L; Heywood, Elizabeth B; Bruemmer, Dennis

2016-06-01

Telomerase reverse transcriptase (TERT) maintains telomeres and is rate limiting for replicative life span. While most somatic tissues silence TERT transcription resulting in telomere shortening, cells derived from cancer or cardiovascular diseases express TERT and activate telomerase. In the present study, we demonstrate that histone deacetylase (HDAC) inhibition induces TERT transcription and promoter activation. At the protein level in contrast, HDAC inhibition decreases TERT protein abundance through enhanced degradation, which decreases telomerase activity and induces senescence. Finally, we demonstrate that HDAC inhibition decreases TERT expression during vascular remodeling in vivo. These data illustrate a differential regulation of TERT transcription and protein stability by HDAC inhibition and suggest that TERT may constitute an important target for the anti-proliferative efficacy of HDAC inhibitors. © 2015 Wiley Periodicals, Inc.

YAP regulates neuronal differentiation through Sonic hedgehog signaling pathway

International Nuclear Information System (INIS)

Lin, Yi-Ting; Ding, Jing-Ya; Li, Ming-Yang; Yeh, Tien-Shun; Wang, Tsu-Wei; Yu, Jenn-Yah

2012-01-01

Tight regulation of cell numbers by controlling cell proliferation and apoptosis is important during development. Recently, the Hippo pathway has been shown to regulate tissue growth and organ size in Drosophila. In mammalian cells, it also affects cell proliferation and differentiation in various tissues, including the nervous system. Interplay of several signaling cascades, such as Notch, Wnt, and Sonic Hedgehog (Shh) pathways, control cell proliferation during neuronal differentiation. However, it remains unclear whether the Hippo pathway coordinates with other signaling cascades in regulating neuronal differentiation. Here, we used P19 cells, a mouse embryonic carcinoma cell line, as a model to study roles of YAP, a core component of the Hippo pathway, in neuronal differentiation. P19 cells can be induced to differentiate into neurons by expressing a neural bHLH transcription factor gene Ascl1. Our results showed that YAP promoted cell proliferation and inhibited neuronal differentiation. Expression of Yap activated Shh but not Wnt or Notch signaling activity during neuronal differentiation. Furthermore, expression of Yap increased the expression of Patched homolog 1 (Ptch1), a downstream target of the Shh signaling. Knockdown of Gli2, a transcription factor of the Shh pathway, promoted neuronal differentiation even when Yap was over-expressed. We further demonstrated that over-expression of Yap inhibited neuronal differentiation in primary mouse cortical progenitors and Gli2 knockdown rescued the differentiation defect in Yap over-expressing cells. In conclusion, our study reveals that Shh signaling acts downstream of YAP in regulating neuronal differentiation. -- Highlights: ► YAP promotes cell proliferation and inhibits neuronal differentiation in P19 cells. ► YAP promotes Sonic hedgehog signaling activity during neuronal differentiation. ► Knockdown of Gli2 rescues the Yap-overexpression phenotype in P19 cells. ► Knockdown of Gli2 rescues the Yap

YAP regulates neuronal differentiation through Sonic hedgehog signaling pathway

Energy Technology Data Exchange (ETDEWEB)

Lin, Yi-Ting; Ding, Jing-Ya [Department of Life Sciences and Institute of Genome Sciences, National Yang-Ming University, Taipei 112, Taiwan (China); Li, Ming-Yang [Department of Life Science, National Taiwan Normal University, Taipei 116, Taiwan (China); Yeh, Tien-Shun [Department of Anatomy and Cell Biology, National Yang-Ming University, Taipei 112, Taiwan (China); Wang, Tsu-Wei [Department of Life Science, National Taiwan Normal University, Taipei 116, Taiwan (China); Yu, Jenn-Yah [Department of Life Sciences and Institute of Genome Sciences, National Yang-Ming University, Taipei 112, Taiwan (China); Brain Research Center, National Yang-Ming University, Taipei 112, Taiwan (China)

2012-09-10

Tight regulation of cell numbers by controlling cell proliferation and apoptosis is important during development. Recently, the Hippo pathway has been shown to regulate tissue growth and organ size in Drosophila. In mammalian cells, it also affects cell proliferation and differentiation in various tissues, including the nervous system. Interplay of several signaling cascades, such as Notch, Wnt, and Sonic Hedgehog (Shh) pathways, control cell proliferation during neuronal differentiation. However, it remains unclear whether the Hippo pathway coordinates with other signaling cascades in regulating neuronal differentiation. Here, we used P19 cells, a mouse embryonic carcinoma cell line, as a model to study roles of YAP, a core component of the Hippo pathway, in neuronal differentiation. P19 cells can be induced to differentiate into neurons by expressing a neural bHLH transcription factor gene Ascl1. Our results showed that YAP promoted cell proliferation and inhibited neuronal differentiation. Expression of Yap activated Shh but not Wnt or Notch signaling activity during neuronal differentiation. Furthermore, expression of Yap increased the expression of Patched homolog 1 (Ptch1), a downstream target of the Shh signaling. Knockdown of Gli2, a transcription factor of the Shh pathway, promoted neuronal differentiation even when Yap was over-expressed. We further demonstrated that over-expression of Yap inhibited neuronal differentiation in primary mouse cortical progenitors and Gli2 knockdown rescued the differentiation defect in Yap over-expressing cells. In conclusion, our study reveals that Shh signaling acts downstream of YAP in regulating neuronal differentiation. -- Highlights: Black-Right-Pointing-Pointer YAP promotes cell proliferation and inhibits neuronal differentiation in P19 cells. Black-Right-Pointing-Pointer YAP promotes Sonic hedgehog signaling activity during neuronal differentiation. Black-Right-Pointing-Pointer Knockdown of Gli2 rescues the Yap

Growth/differentiation factor 15 promotes EGFR signalling, and regulates proliferation and migration in the hippocampus of neonatal and young adult mice.

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Carrillo-García, Carmen; Prochnow, Sebastian; Simeonova, Ina K; Strelau, Jens; Hölzl-Wenig, Gabriele; Mandl, Claudia; Unsicker, Klaus; von Bohlen Und Halbach, Oliver; Ciccolini, Francesca

2014-02-01

The activation of epidermal growth factor receptor (EGFR) affects multiple aspects of neural precursor behaviour, including proliferation and migration. Telencephalic precursors acquire EGF responsiveness and upregulate EGFR expression at late stages of development. The events regulating this process and its significance are still unclear. We here show that in the developing and postnatal hippocampus (HP), growth/differentiation factor (GDF) 15 and EGFR are co-expressed in primitive precursors as well as in more differentiated cells. We also provide evidence that GDF15 promotes responsiveness to EGF and EGFR expression in hippocampal precursors through a mechanism that requires active CXC chemokine receptor (CXCR) 4. Besides EGFR expression, GDF15 ablation also leads to decreased proliferation and migration. In particular, lack of GDF15 impairs both processes in the cornu ammonis (CA) 1 and only proliferation in the dentate gyrus (DG). Importantly, migration and proliferation in the mutant HP were altered only perinatally, when EGFR expression was also affected. These data suggest that GDF15 regulates migration and proliferation by promoting EGFR signalling in the perinatal HP and represent a first description of a functional role for GDF15 in the developing telencephalon.

Indirect presentation in the thymus limits naive and regulatory T-cell differentiation by promoting deletion of self-reactive thymocytes.

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Yap, Jin Yan; Wirasinha, Rushika C; Chan, Anna; Howard, Debbie R; Goodnow, Christopher C; Daley, Stephen R

2018-02-07

Acquisition of T-cell central tolerance involves distinct pathways of self-antigen presentation to thymocytes. One pathway termed indirect presentation requires a self-antigen transfer step from thymic epithelial cells (TECs) to bone marrow-derived cells before the self-antigen is presented to thymocytes. The role of indirect presentation in central tolerance is context-dependent, potentially due to variation in self-antigen expression, processing and presentation in the thymus. Here, we report experiments in mice in which TECs expressed a membrane-bound transgenic self-antigen, hen egg lysozyme (HEL), from either the insulin (insHEL) or thyroglobulin (thyroHEL) promoter. Intrathymic HEL expression was less abundant and more confined to the medulla in insHEL mice compared with thyroHEL mice. When indirect presentation was impaired by generating mice lacking MHC class II expression in bone marrow-derived antigen-presenting cells, insHEL-mediated thymocyte deletion was abolished, whereas thyroHEL-mediated deletion occurred at a later stage of thymocyte development and Foxp3 + regulatory T-cell differentiation increased. Indirect presentation increased the strength of T-cell receptor signalling that both self-antigens induced in thymocytes, as assessed by Helios expression. Hence, indirect presentation limits the differentiation of naive and regulatory T cells by promoting deletion of self-reactive thymocytes. © 2018 John Wiley & Sons Ltd.

Overexpression and cosuppression of xylem-related genes in an early xylem differentiation stage-specific manner by the AtTED4 promoter.

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Endo, Satoshi; Iwamoto, Kuninori; Fukuda, Hiroo

2018-02-01

Tissue-specific overexpression of useful genes, which we can design according to their cause-and-effect relationships, often gives valuable gain-of-function phenotypes. To develop genetic tools in woody biomass engineering, we produced a collection of Arabidopsis lines that possess chimeric genes of a promoter of an early xylem differentiation stage-specific gene, Arabidopsis Tracheary Element Differentiation-related 4 (AtTED4) and late xylem development-associated genes, many of which are uncharacterized. The AtTED4 promoter directed the expected expression of transgenes in developing vascular tissues from young to mature stage. Of T2 lines examined, 42%, 49% and 9% were judged as lines with the nonrepeat type insertion, the simple repeat type insertion and the other repeat type insertion of transgenes. In 174 T3 lines, overexpression lines were confirmed for 37 genes, whereas only cosuppression lines were produced for eight genes. The AtTED4 promoter activity was high enough to overexpress a wide range of genes over wild-type expression levels, even though the wild-type expression is much higher than AtTED4 expression for several genes. As a typical example, we investigated phenotypes of pAtTED4::At5g60490 plants, in which both overexpression and cosuppression lines were included. Overexpression but not cosuppression lines showed accelerated xylem development, suggesting the positive role of At5g60490 in xylem development. Taken together, this study provides valuable results about behaviours of various genes expressed under an early xylem-specific promoter and about usefulness of their lines as genetic tools in woody biomass engineering. © 2017 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.

The ageing phenome: caloric restriction and hormones promote neural cell survival, growth, and de-differentiation.

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Timiras, Paola S; Yaghmaie, Farzin; Saeed, Omar; Thung, Elaine; Chinn, Garrett

2005-01-01

The phenome represents the observable properties of an organism that have developed under the continued influences of both genome and environmental factors. Phenotypic properties are expressed through the functions of cells, organs and body systems that operate optimally, close to equilibrium. In complex organisms, maintenance of the equilibrium is achieved by the interplay of several regulatory mechanisms. In the elderly, dynamic instability may lead to progressive loss of normal function, failure of adaptation and increased pathology. Extensive research (reported elsewhere in this journal) has demonstrated that genetic manipulations of endocrine signaling in flies, worms and mice increase longevity. Another effective strategy for prolonging the lifespan is caloric restriction: in data presented here, the persistence of estrogen-sensitive cells in the hypothalamus of caloric restricted 22-month-old female mice, may explain the persistence of reproductive function at an age, when reproductive function has long ceased in ad libitum fed controls. Still another strategy utilizes the effects of epidermal growth factor (EGF) to promote in vitro proliferation of neuroglia, astrocytes and oligodendrocytes. Their subsequent de-differentiation generates immature precursor cells potentially capable of differentiating into neuroblasts and neurons. These and other examples suggest that, in terms of functional outcomes, "the genome proposes but the phenome disposes".

Glass promotes the differentiation of neuronal and non-neuronal cell types in the Drosophila eye

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Morrison, Carolyn A.; Chen, Hao; Cook, Tiffany; Brown, Stuart

2018-01-01

Transcriptional regulators can specify different cell types from a pool of equivalent progenitors by activating distinct developmental programs. The Glass transcription factor is expressed in all progenitors in the developing Drosophila eye, and is maintained in both neuronal and non-neuronal cell types. Glass is required for neuronal progenitors to differentiate as photoreceptors, but its role in non-neuronal cone and pigment cells is unknown. To determine whether Glass activity is limited to neuronal lineages, we compared the effects of misexpressing it in neuroblasts of the larval brain and in epithelial cells of the wing disc. Glass activated overlapping but distinct sets of genes in these neuronal and non-neuronal contexts, including markers of photoreceptors, cone cells and pigment cells. Coexpression of other transcription factors such as Pax2, Eyes absent, Lozenge and Escargot enabled Glass to induce additional genes characteristic of the non-neuronal cell types. Cell type-specific glass mutations generated in cone or pigment cells using somatic CRISPR revealed autonomous developmental defects, and expressing Glass specifically in these cells partially rescued glass mutant phenotypes. These results indicate that Glass is a determinant of organ identity that acts in both neuronal and non-neuronal cells to promote their differentiation into functional components of the eye. PMID:29324767

miR-140-5p regulates hypoxia-mediated human pulmonary artery smooth muscle cell proliferation, apoptosis and differentiation by targeting Dnmt1 and promoting SOD2 expression

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Zhang, Yanwei; Xu, Jing, E-mail: xujingdoc@163.com

2016-04-22

miR-140-5p is down-regulated in patients with pulmonary arterial hypertension (PAH) and experimental models of PAH, and inhibits hypoxia-mediated pulmonary artery smooth muscle cell (PASMC) proliferation in vitro. Delivery of synthetic miR-140-5p prevents and treats established, experimental PAH. DNA methyltransferase 1 (Dnmt1) is up-regulated in PAH associated human PASMCs (HPASMCs), which promotes the development of PAH by hypermethylation of CpG islands within the promoter for superoxide dismutase 2 (SOD2) and down-regulating SOD2 expression. We searched for miR-140-5p targets using TargetScan, PicTar and MiRanda tools, and found that Dnmt1 is a potential target of miR-140-5p. Based on these findings, we speculated that miR-140-5p might target Dnmt1 and regulate SOD2 expression to regulate hypoxia-mediated HPASMC proliferation, apoptosis and differentiation. We detected the expression of miR-140-5p, Dnmt1 and SOD2 by quantitative real-time polymerase chain reaction (qRT-PCR) and western blot assays, respectively, and found down-regulation of miR-140-5p and SOD2 and up-regulation of Dnmt1 exist in PAH tissues and hypoxia-mediated HPASMCs. Cell proliferation, apoptosis and differentiation detection showed that miR-140-5p inhibits proliferation and promotes apoptosis and differentiation of HPASMCs in hypoxia, while the effect of Dnmt1 on hypoxia-mediated HPASMCs is reversed. Luciferase assay confirmed that miR-140-5p targets Dnmt1 directly. An inverse correlation is also found between miR-140-5p and Dnmt1 in HPASMCs. In addition, we further investigated whether miR-140-5p and Dnmt1 regulate HPASMC proliferation, apoptosis and differentiation by regulating SOD2 expression, and the results confirmed our speculation. Taken together, these results indicated that miR-140-5p at least partly targets Dnmt1 and regulates SOD2 expression to inhibit proliferation and promote apoptosis and differentiation of HPASMCs in hypoxia. - Highlights: • miR-140-5p and SOD2 are down

Hematopoietic stem cell-derived exosomes promote hematopoietic differentiation of mouse embryonic stem cells in vitro via inhibiting the miR126/Notch1 pathway.

Science.gov (United States)

Liao, Feng-Ling; Tan, Lin; Liu, Hua; Wang, Jin-Ju; Ma, Xiao-Tang; Zhao, Bin; Chen, Yanfang; Bihl, Ji; Yang, Yi; Chen, Ri-Ling

2018-04-01

Cell-derived exosomes (EXs) can modulate target cell differentiation via microRNAs (miRs) that they carried. Previous studies have shown that miR126 is highly expressed in hematopoietic stem cells (HSCs) and plays a role in hematopoiesis via modulating the Notch pathway that participates in progenitors' cell fate decisions. In this study we investigated whether HSC-derived EXs (HSC-EXs) could affect the differentiation of mouse embryonic stem cells (ESCs) into HSCs. We prepared HSC-EXs con , HSC-EXs sc and HSC-EXs miR126 from control HSCs and the HSCs transfected with scramble control or miR126 mimics, respectively. HSC-EXs were isolated by ultracentrifugation and analyzed using nanoparticle tracking analysis. We incubated the collected EXs with mouse ESCs over a 10-d differentiation induction period, during which HSC-EXs and a Notch pathway activator (Jagged1, 100 ng/mL) were added to the cultures every 3 d. After the 10-d differentiation period, the expression levels of miR126, SSEA1, CD117, Sca1, Notch1 and Hes1 in ESCs were assessed. The generated HSCs were validated by flow cytometry using antibodies against HSC markers (CD117, CD34 and Sca1). Our results revealed that: (1) transfection with miR126 mimics significantly increased miR126 levels in HSC-EXs miR126 . (2) HSC-EX co-culture promoted mouse ESCs differentiation into HSCs with the most prominent effect found in the HSC-EXs miR126 co-culture. (3) HSC differentiation was verified by reduced SSEA1 expression and increased CD117 and Sca1 expression. (4) All the effects caused by HSC-EXs were accompanied by significant reduction of Notch1 and Hes1 expression, thus inhibition of the Notch1/Hes1 pathway, whereas activation of Notch by Jagged1 abolished the effects of HSC-EXs miR126 . In conclusion, HSC-EXs promote hematopoietic differentiation of mouse ESCs in vitro by inhibiting the miR126/Notch1 pathway.

Lin28B promotes Müller glial cell de-differentiation and proliferation in the regenerative rat retinas

Science.gov (United States)

Tao, Zui; Zhao, Chen; Jian, Qian; Gillies, Mark; Xu, Haiwei; Yin, Zheng Qin

2016-01-01

Retinal regeneration and repair are severely impeded in higher mammalian animals. Although Müller cells can be activated and show some characteristics of progenitor cells when injured or under pathological conditions, they quickly form gliosis scars. Unfortunately, the basic mechanisms that impede retinal regeneration remain unknown. We studied retinas from Royal College of Surgeon (RCS) rats and found that let-7 family molecules, let-7e and let-7i, were significantly overexpressed in Müller cells of degenerative retinas. It demonstrated that down-regulation of the RNA binding protein Lin28B was one of the key factors leading to the overexpression of let-7e and let-7i. Lin28B ectopic expression in the Müller cells suppressed overexpression of let-7e and let-7i, stimulated and mobilized Müller glia de-differentiation, proliferation, promoted neuronal commitment, and inhibited glial fate acquisition of de-differentiated Müller cells. ERG recordings revealed that the amplitudes of a-wave and b-wave were improved significantly after Lin28B was delivered into the subretinal space of RCS rats. In summary, down-regulation of Lin28B as well as up-regulation of let-7e and let-7i may be the main factors that impede Müller cell de-differentiation and proliferation in the retina of RCS rats. PMID:27384999

Valproic Acid Arrests Proliferation but Promotes Neuronal Differentiation of Adult Spinal NSPCs from SCI Rats.

Science.gov (United States)

Chu, Weihua; Yuan, Jichao; Huang, Lei; Xiang, Xin; Zhu, Haitao; Chen, Fei; Chen, Yanyan; Lin, Jiangkai; Feng, Hua

2015-07-01

Although the adult spinal cord contains a population of multipotent neural stem/precursor cells (NSPCs) exhibiting the potential to replace neurons, endogenous neurogenesis is very limited after spinal cord injury (SCI) because the activated NSPCs primarily differentiate into astrocytes rather than neurons. Valproic acid (VPA), a histone deacetylase inhibitor, exerts multiple pharmacological effects including fate regulation of stem cells. In this study, we cultured adult spinal NSPCs from chronic compressive SCI rats and treated with VPA. In spite of inhibiting the proliferation and arresting in the G0/G1 phase of NSPCs, VPA markedly promoted neuronal differentiation (β-tubulin III(+) cells) as well as decreased astrocytic differentiation (GFAP(+) cells). Cell cycle regulator p21(Cip/WAF1) and proneural genes Ngn2 and NeuroD1 were increased in the two processes respectively. In vivo, to minimize the possible inhibitory effects of VPA to the proliferation of NSPCs as well as avoid other neuroprotections of VPA in acute phase of SCI, we carried out a delayed intraperitoneal injection of VPA (150 mg/kg/12 h) to SCI rats from day 15 to day 22 after injury. Both of the newborn neuron marker doublecortin and the mature neuron marker neuron-specific nuclear protein were significantly enhanced after VPA treatment in the epicenter and adjacent segments of the injured spinal cord. Although the impaired corticospinal tracks had not significantly improved, Basso-Beattie-Bresnahan scores in VPA treatment group were better than control. Our study provide the first evidence that administration of VPA enhances the neurogenic potential of NSPCs after SCI and reveal the therapeutic value of delayed treatment of VPA to SCI.

MEK5 suppresses osteoblastic differentiation

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Kaneshiro, Shoichi [Department of Orthopaedic Surgery, Japan Community Health Care Organization Osaka Hospital, 4-2-78 Fukushima, Fukushima Ward, Osaka City, Osaka 553-0003 (Japan); Department of Orthopaedic Surgery, Graduate School of Medicine, Osaka University, 2-2 Yamadaoka, Suita, Osaka 565-0871 (Japan); Otsuki, Dai; Yoshida, Kiyoshi; Yoshikawa, Hideki [Department of Orthopaedic Surgery, Graduate School of Medicine, Osaka University, 2-2 Yamadaoka, Suita, Osaka 565-0871 (Japan); Higuchi, Chikahisa, E-mail: c-higuchi@umin.ac.jp [Department of Orthopaedic Surgery, Graduate School of Medicine, Osaka University, 2-2 Yamadaoka, Suita, Osaka 565-0871 (Japan)

2015-07-31

Extracellular signal-regulated kinase 5 (ERK5) is a member of the mitogen-activated protein kinase (MAPK) family and is activated by its upstream kinase, MAPK kinase 5 (MEK5), which is a member of the MEK family. Although the role of MEK5 has been investigated in several fields, little is known about its role in osteoblastic differentiation. In this study, we have demonstrated the role of MEK5 in osteoblastic differentiation in mouse preosteoblastic MC3T3-E1 cells and bone marrow stromal ST2 cells. We found that treatment with BIX02189, an inhibitor of MEK5, increased alkaline phosphatase (ALP) activity and the gene expression of ALP, osteocalcin (OCN) and osterix, as well as it enhanced the calcification of the extracellular matrix. Moreover, osteoblastic cell proliferation decreased at a concentration of greater than 0.5 μM. In addition, knockdown of MEK5 using siRNA induced an increase in ALP activity and in the gene expression of ALP, OCN, and osterix. In contrast, overexpression of wild-type MEK5 decreased ALP activity and attenuated osteoblastic differentiation markers including ALP, OCN and osterix, but promoted cell proliferation. In summary, our results indicated that MEK5 suppressed the osteoblastic differentiation, but promoted osteoblastic cell proliferation. These results implied that MEK5 may play a pivotal role in cell signaling to modulate the differentiation and proliferation of osteoblasts. Thus, inhibition of MEK5 signaling in osteoblasts may be of potential use in the treatment of osteoporosis. - Highlights: • MEK5 inhibitor BIX02189 suppresses proliferation of osteoblasts. • MEK5 knockdown and MEK5 inhibitor promote differentiation of osteoblasts. • MEK5 overexpression inhibits differentiation of osteoblasts.

Transfection of the IHH gene into rabbit BMSCs in a simulated microgravity environment promotes chondrogenic differentiation and inhibits cartilage aging.

Science.gov (United States)

Liu, Peng-Cheng; Liu, Kuan; Liu, Jun-Feng; Xia, Kuo; Chen, Li-Yang; Wu, Xing

2016-09-27

The effect of overexpressing the Indian hedgehog (IHH) gene on the chondrogenic differentiation of rabbit bone marrow-derived mesenchymal stem cells (BMSCs) was investigated in a simulated microgravity environment. An adenovirus plasmid encoding the rabbit IHH gene was constructed in vitro and transfected into rabbit BMSCs. Two large groups were used: conventional cell culture and induction model group and simulated microgravity environment group. Each large group was further divided into blank control group, GFP transfection group, and IHH transfection group. During differentiation induction, the expression levels of cartilage-related and cartilage hypertrophy-related genes and proteins in each group were determined. In the conventional model, the IHH transfection group expressed high levels of cartilage-related factors (Coll2 and ANCN) at the early stage of differentiation induction and expressed high levels of cartilage hypertrophy-related factors (Coll10, annexin 5, and ALP) at the late stage. Under the simulated microgravity environment, the IHH transfection group expressed high levels of cartilage-related factors and low levels of cartilage hypertrophy-related factors at all stages of differentiation induction. Under the simulated microgravity environment, transfection of the IHH gene into BMSCs effectively promoted the generation of cartilage and inhibited cartilage aging and osteogenesis. Therefore, this technique is suitable for cartilage tissue engineering.

Indian hedgehog signaling promotes chondrocyte differentiation in enchondral ossification in human cervical ossification of the posterior longitudinal ligament.

Science.gov (United States)

Sugita, Daisuke; Yayama, Takafumi; Uchida, Kenzo; Kokubo, Yasuo; Nakajima, Hideaki; Yamagishi, Atsushi; Takeura, Naoto; Baba, Hisatoshi

2013-10-15

indicated that overexpression of Ihh signaling promotes abnormal chondrocyte differentiation in enchondral ossification and enhances bone formation in OPLL.

Vav promotes differentiation of human tumoral myeloid precursors

International Nuclear Information System (INIS)

Bertagnolo, Valeria; Brugnoli, Federica; Mischiati, Carlo; Sereni, Alessia; Bavelloni, Alberto; Carini, Cinzia; Capitani, Silvano

2005-01-01

Vav is one of the genetic markers that correlate with the differentiation of hematopoietic cells. In T and B cells, it appears crucial for both development and functions, while, in non-lymphoid hematopoietic cells, Vav seems not involved in cell maturation, but rather in the response of mature cells to agonist-dependent proliferation and phagocytosis. We have previously demonstrated that the amount and the tyrosine phosphorylation of Vav are up-regulated in both whole cells and nuclei of tumoral promyelocytes induced to granulocytic maturation by ATRA and that tyrosine-phosphorylated Vav does not display any ATRA-induced GEF activity but contributes to the regulation of PI 3-K activity. In this study, we report that Vav accumulates in nuclei of ATRA-treated APL-derived cells and that the down-modulation of Vav prevents differentiation of tumoral promyelocytes, indicating that it is a key molecule in ATRA-dependent myeloid maturation. On the other hand, the overexpression of Vav induces an increased expression of surface markers of granulocytic differentiation without affecting the maturation-related changes of the nuclear morphology. Consistent with an effect of Vav on the transcriptional machinery, array profiling shows that the inhibition of the Syk-dependent tyrosine phosphorylation of Vav reduces the number of ATRA-induced genes. Our data support the unprecedented notion that Vav plays crucial functions in the maturation process of myeloid cells, and suggest that Vav can be regarded as a potential target for the therapeutic treatment of myeloproliferative disorders

Suv4-20h histone methyltransferases promote neuroectodermal differentiation by silencing the pluripotency-associated Oct-25 gene.

Directory of Open Access Journals (Sweden)

Dario Nicetto

Full Text Available Post-translational modifications (PTMs of histones exert fundamental roles in regulating gene expression. During development, groups of PTMs are constrained by unknown mechanisms into combinatorial patterns, which facilitate transitions from uncommitted embryonic cells into differentiated somatic cell lineages. Repressive histone modifications such as H3K9me3 or H3K27me3 have been investigated in detail, but the role of H4K20me3 in development is currently unknown. Here we show that Xenopus laevis Suv4-20h1 and h2 histone methyltransferases (HMTases are essential for induction and differentiation of the neuroectoderm. Morpholino-mediated knockdown of the two HMTases leads to a selective and specific downregulation of genes controlling neural induction, thereby effectively blocking differentiation of the neuroectoderm. Global transcriptome analysis supports the notion that these effects arise from the transcriptional deregulation of specific genes rather than widespread, pleiotropic effects. Interestingly, morphant embryos fail to repress the Oct4-related Xenopus gene Oct-25. We validate Oct-25 as a direct target of xSu4-20h enzyme mediated gene repression, showing by chromatin immunoprecipitaton that it is decorated with the H4K20me3 mark downstream of the promoter in normal, but not in double-morphant, embryos. Since knockdown of Oct-25 protein significantly rescues the neural differentiation defect in xSuv4-20h double-morphant embryos, we conclude that the epistatic relationship between Suv4-20h enzymes and Oct-25 controls the transit from pluripotent to differentiation-competent neural cells. Consistent with these results in Xenopus, murine Suv4-20h1/h2 double-knockout embryonic stem (DKO ES cells exhibit increased Oct4 protein levels before and during EB formation, and reveal a compromised and biased capacity for in vitro differentiation, when compared to normal ES cells. Together, these results suggest a regulatory mechanism, conserved

Nucleic acid metabolism in human chronic liver disease by in vitro autoradiography. I. Altered RNA metabolism

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Yoshida, T [Okayama Univ. (Japan). School of Medicine

1976-06-01

Biopsy liver specimens from healthy control subjects (N=5) and patients with various liver diseases (N=43) were investigated by the vitro autoradiography. The Leevy technique of adding /sup 3/H-5-uridine (/sup 3/H-U) to the incubation medium was used. In healthy subjects labeling with /sup 3/H-U was observed mostly in hepatocytes and Kupffer cells and the frequency of /sup 3/H-U labeled cells was extremely high. Higher frequencies of labeled fibrocytes and endothelial cells of the blood vessel were found in acute hepatitis than in control subjects. In the active form of chronic hepatitis, significantly higher counts of labeled fibrocytes, ductular cells and lymphocytes were found. In patients with acute hepatitis or the inactive form of chronic hepatitis, only a few labeled lymphocytes were observed. Larger numbers of labeled fibrocytes were found in patients with chronic hepatitis with sublobular hepatic necrosis, than in patients with the active form of chronic hepatitis. In cirrhotic livers, marked increases of labeled ductular cells, fibrocytes and bile duct cells were found. No significant labeling differences were observed in the hepatocytes of various liver diseases. In chronic hepatitis with sublobular hepatic necrosis, a more significant decrease of labeled Kupffer cells was present than in the inactive form of chronic hepatitis. Labeled ductular cells and fibrocytes increased as the disease progressed from acute hepatitis to liver cirrhosis. The labeling index of rosettes cells was intermediate between the hepatocytes and ductular cells. The ratio of labeled parenchymal to non-parenchymal cells decreased proportionally from chronic hepatitis to cirrhosis.

Multiple nodules on the sole of the foot

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Alyssa J Miceli

2015-01-01

Full Text Available Ledderhose disease, or plantar fibromatosis, is a benign hyperproliferative disorder of the plantar aponeurosis. It presents as one or more round, firm slow-growing plaques or nodules on the plantar surface of the foot, typically on the medial side. The etiology is unknown, though it has been associated with trauma, liver disease, diabetes mellitus, epilepsy and alcoholism. Histopathological examination of plantar fibromatosis reveals dense fibrocellular tissue with parallel and nodular arrays of fibrocytes and fibrillar collagen with a distinctive cork-screw morphology. The differential diagnosis includes various fibroblastic and myofibroblastic proliferations.

Sirtuin1 promotes osteogenic differentiation through downregulation of peroxisome proliferator-activated receptor γ in MC3T3-E1 cells

International Nuclear Information System (INIS)

Qu, Bo; Ma, Yuan; Yan, Ming; Gong, Kai; Liang, Feng; Deng, Shaolin; Jiang, Kai; Ma, Zehui; Pan, Xianming

2016-01-01

osteoporosis. - Highlights: • Sirt1 inhibits PPARγ signaling in MC3T3-E1 cells. • PPARγ negatively regulates osteogenic differentiation of MC3T3-E1 cells. • Sirt1 promotes osteogenic differentiation through downregulation of PPARγ.

Sirtuin1 promotes osteogenic differentiation through downregulation of peroxisome proliferator-activated receptor γ in MC3T3-E1 cells

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Qu, Bo [Department of Orthopaedics, Chengdu Military General Hospital, Chengdu 610083 (China); Ma, Yuan [Department of Neurosurgery, Chengdu Military General Hospital, Chengdu 610083 (China); Yan, Ming [Department of Orthopaedics, Xijing Hospital of The Fourth Military Medical University, Xi’an 710032 (China); Gong, Kai; Liang, Feng; Deng, Shaolin; Jiang, Kai; Ma, Zehui [Department of Orthopaedics, Chengdu Military General Hospital, Chengdu 610083 (China); Pan, Xianming, E-mail: xianmingpanxj@163.com [Department of Orthopaedics, Chengdu Military General Hospital, Chengdu 610083 (China)

2016-09-09

of osteoporosis. - Highlights: • Sirt1 inhibits PPARγ signaling in MC3T3-E1 cells. • PPARγ negatively regulates osteogenic differentiation of MC3T3-E1 cells. • Sirt1 promotes osteogenic differentiation through downregulation of PPARγ.

An upstream activation element exerting differential transcriptional activation on an archaeal promoter

DEFF Research Database (Denmark)

Peng, Nan; Xia, Qiu; Chen, Zhengjun

2009-01-01

S gene encoding an arabinose binding protein was characterized using an Sulfolobus islandicus reporter gene system. The minimal active araS promoter (P(araS)) was found to be 59 nucleotides long and harboured four promoter elements: an ara-box, an upstream transcription factor B-responsive element (BRE......), a TATA-box and a proximal promoter element, each of which contained important nucleotides that either greatly decreased or completely abolished promoter activity upon mutagenesis. The basal araS promoter was virtually inactive due to intrinsically weak BRE element, and the upstream activating sequence...... (UAS) ara-box activated the basal promoter by recruiting transcription factor B to its BRE. While this UAS ensured a general expression from an inactive or weak basal promoter in the presence of other tested carbon resources, it exhibited a strong arabinose-responsive transcriptional activation. To our...

TrxR2 deficiencies promote chondrogenic differentiation and induce apoptosis of chondrocytes through mitochondrial reactive oxygen species

International Nuclear Information System (INIS)

Yan, Jidong; Xu, Jing; Fei, Yao; Jiang, Congshan; Zhu, Wenhua; Han, Yan; Lu, Shemin

2016-01-01

Thioredoxin reductase 2 (TrxR2) is a selenium (Se) containing protein. Se deficiency is associated with an endemic osteoarthropathy characterized by impaired cartilage formation. It is unclear whether TrxR2 have roles in cartilage function. We examined the effects of TrxR2 on chondrogenic ATDC5 cells through shRNA-mediated gene silencing of TrxR2. We demonstrated TrxR2 deficiencies could enhance chondrogenic differentiation and apoptosis of ATDC5 cells. TrxR2 deficiencies increased accumulation of cartilage glycosaminoglycans (GAGs) and mineralization. TrxR2 deficiencies also stimulated expression of extracellular (ECM) gene including Collagen II and Aggrecan. The enhanced chondrogenic properties were further confirmed by activation of Akt signaling which are required for chondrogenesis. In addition, TrxR2 deficiencies promoted chondrocyte proliferation through acceleration of cell cycle progression by increase in both S and G2/M phase cell distribution accompanied with induction of parathyroid hormone-related protein (PTHrP). Moreover, TrxR2 deficiencies induced chondrocyte death via apoptosis and increased cell sensitivity to exogenous oxidative stress. Furthermore, TrxR2 deficiencies induced emission of mitochondrial reactive oxygen species (ROS) without alteration of mitochondrial membrane potential and intracellular ATP content. Finally, treatment of TrxR2 deficiency cells with N-acetylcysteine (NAC) inhibited mitochondrial ROS production and chondrocyte apoptosis. NAC also prevented chondrogenic differentiation of TrxR2 deficiency cells by suppression of ECM gene expression, GAGs accumulation and mineralization, as well as attenuation of Akt signaling. Thus, TrxR2-mediated mitochondrial integrity is indispensable for chondrogenic differentiation of ATDC5 cells. TrxR2 deficiency-induced impaired proliferation and death of chondrocytes may be the pathological mechanism of the osteoarthropathy due to Se deficiency. Notably, this study also uncover the roles of

TrxR2 deficiencies promote chondrogenic differentiation and induce apoptosis of chondrocytes through mitochondrial reactive oxygen species

Energy Technology Data Exchange (ETDEWEB)

Yan, Jidong [Department of Human Anatomy, Histology and Embryology, School of Basic Medical Sciences, Xi’an Jiaotong University Health Science Center, Xi’an, Shaanxi 710061 (China); Xu, Jing [Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Xi’an Jiaotong University Health Science Center, Xi’an, Shaanxi 710061 (China); Fei, Yao [College of Life Sciences, Northwest University, Xi’an, Shaanxi Province 710069 (China); Jiang, Congshan; Zhu, Wenhua; Han, Yan [Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Xi’an Jiaotong University Health Science Center, Xi’an, Shaanxi 710061 (China); Lu, Shemin, E-mail: lushemin@xjtu.edu.cn [Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Xi’an Jiaotong University Health Science Center, Xi’an, Shaanxi 710061 (China); Key Laboratory of Environment and Genes Related to Diseases, Xi’an Jiaotong University, Ministry of Education of China (China)

2016-05-15

Thioredoxin reductase 2 (TrxR2) is a selenium (Se) containing protein. Se deficiency is associated with an endemic osteoarthropathy characterized by impaired cartilage formation. It is unclear whether TrxR2 have roles in cartilage function. We examined the effects of TrxR2 on chondrogenic ATDC5 cells through shRNA-mediated gene silencing of TrxR2. We demonstrated TrxR2 deficiencies could enhance chondrogenic differentiation and apoptosis of ATDC5 cells. TrxR2 deficiencies increased accumulation of cartilage glycosaminoglycans (GAGs) and mineralization. TrxR2 deficiencies also stimulated expression of extracellular (ECM) gene including Collagen II and Aggrecan. The enhanced chondrogenic properties were further confirmed by activation of Akt signaling which are required for chondrogenesis. In addition, TrxR2 deficiencies promoted chondrocyte proliferation through acceleration of cell cycle progression by increase in both S and G2/M phase cell distribution accompanied with induction of parathyroid hormone-related protein (PTHrP). Moreover, TrxR2 deficiencies induced chondrocyte death via apoptosis and increased cell sensitivity to exogenous oxidative stress. Furthermore, TrxR2 deficiencies induced emission of mitochondrial reactive oxygen species (ROS) without alteration of mitochondrial membrane potential and intracellular ATP content. Finally, treatment of TrxR2 deficiency cells with N-acetylcysteine (NAC) inhibited mitochondrial ROS production and chondrocyte apoptosis. NAC also prevented chondrogenic differentiation of TrxR2 deficiency cells by suppression of ECM gene expression, GAGs accumulation and mineralization, as well as attenuation of Akt signaling. Thus, TrxR2-mediated mitochondrial integrity is indispensable for chondrogenic differentiation of ATDC5 cells. TrxR2 deficiency-induced impaired proliferation and death of chondrocytes may be the pathological mechanism of the osteoarthropathy due to Se deficiency. Notably, this study also uncover the roles of

17beta-estradiol promotes the odonto/osteogenic differentiation of stem cells from apical papilla via mitogen-activated protein kinase pathway.

Science.gov (United States)

Li, Yao; Yan, Ming; Wang, Zilu; Zheng, Yangyu; Li, Junjun; Ma, Shu; Liu, Genxia; Yu, Jinhua

2014-11-17

Estrogen plays an important role in the osteogenic differentiation of mesenchymal stem cells, while stem cells from apical papilla (SCAP) can contribute to the formation of dentin/bone-like tissues. To date, the effects of estrogen on the differentiation of SCAP remain unclear. SCAP was isolated and treated with 10⁻⁷ M 17beta-estradiol (E2). The odonto/osteogenic potency and the involvement of mitogen-activated protein kinase (MAPK) signaling pathway were subsequently investigated by using methyl-thiazolyl-tetrazolium (MTT) assay, and other methods. MTT and flow cytometry results demonstrated that E2 treatment had no effect on the proliferation of SCAP in vitro, while alkaline phosphatase (ALP) assay and alizarin red staining showed that E2 can significantly promote ALP activity and mineralization ability in SCAP. Real-time reverse transcription polymerase chain reaction (RT-PCR) and western blot assay revealed that the odonto/osteogenic markers (ALP, DMP1/DMP1, DSPP/DSP, RUNX2/RUNX2, OSX/OSX and OCN/OCN) were significantly upregulated in E2-treated SCAP. In addition, the expression of phosphor-p38 and phosphor-JNK in these stem cells was enhanced by E2 treatment, as was the expression of the nuclear downstream transcription factors including phosphor-Sp1, phosphor-Elk-1, phosphor-c-Jun and phosphor-c-Fos, indicating the activation of MAPK signaling pathway during the odonto/osteogenic differentiation of E2-treated SCAP. Conversely, the differentiation of E2-treated SCAP was inhibited in the presence of MAPK specific inhibitors. The ondonto/osteogenic differentiation of SCAP is enhanced by 10⁻⁷ M 17beta-estradiol via the activation of MAPK signaling pathway.

Sphingosine-1-phosphate promotes the differentiation of human umbilical cord mesenchymal stem cells into cardiomyocytes under the designated culturing conditions

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Zhang Henggui

2011-06-01

Full Text Available Abstract Background It is of growing interest to develop novel approaches to initiate differentiation of mesenchymal stem cells (MSCs into cardiomyocytes. The purpose of this investigation was to determine if Sphingosine-1-phosphate (S1P, a native circulating bioactive lipid metabolite, plays a role in differentiation of human umbilical cord mesenchymal stem cells (HUMSCs into cardiomyocytes. We also developed an engineered cell sheet from these HUMSCs derived cardiomyocytes by using a temperature-responsive polymer, poly(N-isopropylacrylamide (PIPAAm cell sheet technology. Methods Cardiomyogenic differentiation of HUMSCs was performed by culturing these cells with either designated cardiomyocytes conditioned medium (CMCM alone, or with 1 μM S1P; or DMEM with 10% FBS + 1 μM S1P. Cardiomyogenic differentiation was determined by immunocytochemical analysis of expression of cardiomyocyte markers and patch clamping recording of the action potential. Results A cardiomyocyte-like morphology and the expression of α-actinin and myosin heavy chain (MHC proteins can be observed in both CMCM culturing or CMCM+S1P culturing groups after 5 days' culturing, however, only the cells in CMCM+S1P culture condition present cardiomyocyte-like action potential and voltage gated currents. A new approach was used to form PIPAAm based temperature-responsive culture surfaces and this successfully produced cell sheets from HUMSCs derived cardiomyocytes. Conclusions This study for the first time demonstrates that S1P potentiates differentiation of HUMSCs towards functional cardiomyocytes under the designated culture conditions. Our engineered cell sheets may provide a potential for clinically applicable myocardial tissues should promote cardiac tissue engineering research.

The CMV early enhancer/chicken beta actin (CAG) promoter can be used to drive transgene expression during the differentiation of murine embryonic stem cells into vascular progenitors

DEFF Research Database (Denmark)

Alexopoulou, Annika N; Couchman, John R; Whiteford, James

2008-01-01

BACKGROUND: Mouse embryonic stem cells cultured in vitro have the ability to differentiate into cells of the three germ layers as well as germ cells. The differentiation mimics early developmental events, including vasculogenesis and early angiogenesis and several differentiation systems are being...... used to identify factors that are important during the formation of the vascular system. Embryonic stem cells are difficult to transfect, while downregulation of promoter activity upon selection of stable transfectants has been reported, rendering the study of proteins by overexpression difficult....... RESULTS: CCE mouse embryonic stem cells were differentiated on collagen type IV for 4-5 days, Flk1+ mesodermal cells were sorted and replated either on collagen type IV in the presence of VEGFA to give rise to endothelial cells and smooth muscle cells or in collagen type I gels for the formation...

MANF Promotes Differentiation and Migration of Neural Progenitor Cells with Potential Neural Regenerative Effects in Stroke

DEFF Research Database (Denmark)

Tseng, Kuan-Yin; Anttila, Jenni E; Khodosevich, Konstantin

2018-01-01

die shortly after injury or are unable to arrive at the infarct boundary. In this study, we demonstrate for the first time that endogenous mesencephalic astrocyte-derived neurotrophic factor (MANF) protects NSCs against oxygen-glucose-deprivation-induced injury and has a crucial role in regulating NPC...... migration. In NSC cultures, MANF protein administration did not affect growth of cells but triggered neuronal and glial differentiation, followed by activation of STAT3. In SVZ explants, MANF overexpression facilitated cell migration and activated the STAT3 and ERK1/2 pathway. Using a rat model of cortical...... stroke, intracerebroventricular injections of MANF did not affect cell proliferation in the SVZ, but promoted migration of doublecortin (DCX)+ cells toward the corpus callosum and infarct boundary on day 14 post-stroke. Long-term infusion of MANF into the peri-infarct zone increased the recruitment...

ISL1 protein transduction promotes cardiomyocyte differentiation from human embryonic stem cells.

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Hananeh Fonoudi

Full Text Available BACKGROUND: Human embryonic stem cells (hESCs have the potential to provide an unlimited source of cardiomyocytes, which are invaluable resources for drug or toxicology screening, medical research, and cell therapy. Currently a number of obstacles exist such as the insufficient efficiency of differentiation protocols, which should be overcome before hESC-derived cardiomyocytes can be used for clinical applications. Although the differentiation efficiency can be improved by the genetic manipulation of hESCs to over-express cardiac-specific transcription factors, these differentiated cells are not safe enough to be applied in cell therapy. Protein transduction has been demonstrated as an alternative approach for increasing the efficiency of hESCs differentiation toward cardiomyocytes. METHODS: We present an efficient protocol for the differentiation of hESCs in suspension by direct introduction of a LIM homeodomain transcription factor, Islet1 (ISL1 recombinant protein into the cells. RESULTS: We found that the highest beating clusters were derived by continuous treatment of hESCs with 40 µg/ml recombinant ISL1 protein during days 1-8 after the initiation of differentiation. The treatment resulted in up to a 3-fold increase in the number of beating areas. In addition, the number of cells that expressed cardiac specific markers (cTnT, CONNEXIN 43, ACTININ, and GATA4 doubled. This protocol was also reproducible for another hESC line. CONCLUSIONS: This study has presented a new, efficient, and reproducible procedure for cardiomyocytes differentiation. Our results will pave the way for scaled up and controlled differentiation of hESCs to be used for biomedical applications in a bioreactor culture system.

Pak3 promotes cell cycle exit and differentiation of β-cells in the embryonic pancreas and is necessary to maintain glucose homeostasis in adult mice.

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Piccand, Julie; Meunier, Aline; Merle, Carole; Jia, Zhengping; Barnier, Jean-Vianney; Gradwohl, Gérard

2014-01-01

The transcription factor neurogenin3 (Ngn3) triggers islet cell differentiation in the developing pancreas. However, little is known about the molecular mechanisms coupling cell cycle exit and differentiation in Ngn3(+) islet progenitors. We identified a novel effector of Ngn3 endocrinogenic function, the p21 protein-activated kinase Pak3, known to control neuronal differentiation and implicated in X-linked intellectual disability in humans. We show that Pak3 expression is initiated in Ngn3(+) endocrine progenitor cells and next maintained in maturing hormone-expressing cells during pancreas development as well as in adult islet cells. In Pak3-deficient embryos, the proliferation of Ngn3(+) progenitors and β-cells is transiently increased concomitantly with an upregulation of Ccnd1. β-Cell differentiation is impaired at E15.5 but resumes at later stages. Pak3-deficient mice do not develop overt diabetes but are glucose intolerant under high-fat diet (HFD). In the intestine, Pak3 is expressed in enteroendocrine cells but is not necessary for their differentiation. Our results indicate that Pak3 is a novel regulator of β-cell differentiation and function. Pak3 acts downstream of Ngn3 to promote cell cycle exit and differentiation in the embryo by a mechanism that might involve repression of Ccnd1. In the adult, Pak3 is required for the proper control of glucose homeostasis under challenging HFD.

Elevation, Not Deforestation, Promotes Genetic Differentiation in a Pioneer Tropical Tree.

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Castilla, Antonio R; Pope, Nathaniel; Jaffé, Rodolfo; Jha, Shalene

2016-01-01

The regeneration of disturbed forest is an essential part of tropical forest ecology, both with respect to natural disturbance regimes and large-scale human-mediated logging, grazing, and agriculture. Pioneer tree species are critical for facilitating the transition from deforested land to secondary forest because they stabilize terrain and enhance connectivity between forest fragments by increasing matrix permeability and initiating disperser community assembly. Despite the ecological importance of early successional species, little is known about their ability to maintain gene flow across deforested landscapes. Utilizing highly polymorphic microsatellite markers, we examined patterns of genetic diversity and differentiation for the pioneer understory tree Miconia affinis across the Isthmus of Panama. Furthermore, we investigated the impact of geographic distance, forest cover, and elevation on genetic differentiation among populations using circuit theory and regression modeling within a landscape genetics framework. We report marked differences in historical and contemporary migration rates and moderately high levels of genetic differentiation in M. affinis populations across the Isthmus of Panama. Genetic differentiation increased significantly with elevation and geographic distance among populations; however, we did not find that forest cover enhanced or reduced genetic differentiation in the study region. Overall, our results reveal strong dispersal for M. affinis across human-altered landscapes, highlighting the potential use of this species for reforestation in tropical regions. Additionally, this study demonstrates the importance of considering topography when designing programs aimed at conserving genetic diversity within degraded tropical landscapes.

Product and Quotient Rules from Logarithmic Differentiation

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Chen, Zhibo

2012-01-01

A new application of logarithmic differentiation is presented, which provides an alternative elegant proof of two basic rules of differentiation: the product rule and the quotient rule. The proof can intrigue students, help promote their critical thinking and rigorous reasoning and deepen their understanding of previously encountered concepts. The…

Collagen Promotes Higher Adhesion, Survival and Proliferation of Mesenchymal Stem Cells.

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Chinnapaka Somaiah

Full Text Available Mesenchymal stem cells (MSC can differentiate into several cell types and are desirable candidates for cell therapy and tissue engineering. However, due to poor cell survival, proliferation and differentiation in the patient, the therapy outcomes have not been satisfactory. Although several studies have been done to understand the conditions that promote proliferation, differentiation and migration of MSC in vitro and in vivo, still there is no clear understanding on the effect of non-cellular bio molecules. Of the many factors that influence the cell behavior, the immediate cell microenvironment plays a major role. In this context, we studied the effect of extracellular matrix (ECM proteins in controlling cell survival, proliferation, migration and directed MSC differentiation. We found that collagen promoted cell proliferation, cell survival under stress and promoted high cell adhesion to the cell culture surface. Increased osteogenic differentiation accompanied by high active RHOA (Ras homology gene family member A levels was exhibited by MSC cultured on collagen. In conclusion, our study shows that collagen will be a suitable matrix for large scale production of MSC with high survival rate and to obtain high osteogenic differentiation for therapy.

Telomerase reverse transcriptase promoter mutations in glandular lesions of the urinary bladder.

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Vail, Eric; Zheng, Xiaoyong; Zhou, Ming; Yang, Ximing; Fallon, John T; Epstein, Jonathan I; Zhong, Minghao

2015-10-01

Glandular lesions of the urinary bladder include a broad spectrum of entities ranging from completely benign to primary and secondary malignancies. The accurate diagnosis of these lesions is both important and challenging. Recently, studies suggest that telomerase reverse transcriptase (TERT) promoter mutations could be a biomarker for urothelial carcinoma (UC). We hypothesized that these mutations can distinguish UC with glandular differentiation from nephrogenic adenoma, primary adenocarcinoma of the urinary bladder (PAUB), or secondary malignancies. Twenty-five cases of benign glandular lesions (including nephrogenic adenoma); 29 cases of UC with glandular differentiation; 10 cases of PAUB; and 10 cases each of metastatic colon cancer, prostatic carcinoma, and carcinoma from Mullerian origin were collected. Slides were reviewed and selected to make sure the lesion was at least 10% to 20% of all tissue. Macrodissection was performed in some of cases, and genomic DNA was extracted from the tissue. Telomerase reverse transcriptase promoter mutations were determined by standard polymerase chain reaction sequencing. Twenty-one cases (72%) of UC with glandular differentiation were positive for TERT promoter mutations. However, none of the remaining cases (total 65 cases of benign lesions, PAUB, and metastatic carcinomas) was positive for TERT promoter mutation. Telomerase reverse transcriptase promoter mutations were highly associated with UC including UC with glandular differentiation but not other glandular lesions of bladder. Therefore, in conjunction with morphologic features, Immunohistochemistry stain profile, and clinical information, TERT promoter mutations could distinguish UC with glandular differentiation from other bladder glandular lesions. In addition, lack of TERT promoter mutations in primary adenocarcinoma of bladder suggests that this entity may have different origin or carcinogenesis from those of UC. Published by Elsevier Inc.

Silk fibroin/chitosan thin film promotes osteogenic and adipogenic differentiation of rat bone marrow-derived mesenchymal stem cells.

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Li, Da-Wei; He, Jin; He, Feng-Li; Liu, Ya-Li; Liu, Yang-Yang; Ye, Ya-Jing; Deng, Xudong; Yin, Da-Chuan

2018-04-01

As a biodegradable polymer thin film, silk fibroin/chitosan composite film overcomes the defects of pure silk fibroin and chitosan films, respectively, and shows remarkable biocompatibility, appropriate hydrophilicity and mechanical properties. Silk fibroin/chitosan thin film can be used not only as metal implant coating for bone injury repair, but also as tissue engineering scaffold for skin, cornea, adipose, and other soft tissue injury repair. However, the biocompatibility of silk fibroin/chitosan thin film for mesenchymal stem cells, a kind of important seed cell of tissue engineering and regenerative medicine, is rarely reported. In this study, silk fibroin/chitosan film was prepared by solvent casting method, and the rat bone marrow-derived mesenchymal stem cells were cultured on the silk fibroin/chitosan thin film. Osteogenic and adipogenic differentiation of rat bone marrow-derived mesenchymal stem cells were induced, respectively. The proliferation ability, osteogenic and adipogenic differentiation abilities of rat bone marrow-derived mesenchymal stem cells were systematically compared between silk fibroin/chitosan thin film and polystyrene tissue culture plates. The results showed that silk fibroin/chitosan thin film not only provided a comparable environment for the growth and proliferation of rat bone marrow-derived mesenchymal stem cells but also promoted their osteogenic and adipogenic differentiation. This work provided information of rat bone marrow-derived mesenchymal stem cells behavior on silk fibroin/chitosan thin film and extended the application of silk fibroin/chitosan thin film. Based on the results, we suggested that the silk fibroin/chitosan thin film could be a promising material for tissue engineering of bone, cartilage, adipose, and skin.

Extracellular matrix aggregates from differentiating embryoid bodies as a scaffold to support ESC proliferation and differentiation.

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Saik-Kia Goh

Full Text Available Embryonic stem cells (ESCs have emerged as potential cell sources for tissue engineering and regeneration owing to its virtually unlimited replicative capacity and the potential to differentiate into a variety of cell types. Current differentiation strategies primarily involve various growth factor/inducer/repressor concoctions with less emphasis on the substrate. Developing biomaterials to promote stem cell proliferation and differentiation could aid in the realization of this goal. Extracellular matrix (ECM components are important physiological regulators, and can provide cues to direct ESC expansion and differentiation. ECM undergoes constant remodeling with surrounding cells to accommodate specific developmental event. In this study, using ESC derived aggregates called embryoid bodies (EB as a model, we characterized the biological nature of ECM in EB after exposure to different treatments: spontaneously differentiated and retinoic acid treated (denoted as SPT and RA, respectively. Next, we extracted this treatment-specific ECM by detergent decellularization methods (Triton X-100, DOC and SDS are compared. The resulting EB ECM scaffolds were seeded with undifferentiated ESCs using a novel cell seeding strategy, and the behavior of ESCs was studied. Our results showed that the optimized protocol efficiently removes cells while retaining crucial ECM and biochemical components. Decellularized ECM from SPT EB gave rise to a more favorable microenvironment for promoting ESC attachment, proliferation, and early differentiation, compared to native EB and decellularized ECM from RA EB. These findings suggest that various treatment conditions allow the formulation of unique ESC-ECM derived scaffolds to enhance ESC bioactivities, including proliferation and differentiation for tissue regeneration applications.

Differential Top10 promoter regulation by six tetracycline analogues in plant cells

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Love, John; Allen, George C.; Gatz, Christiane; Thompson, William F.; Brown, C. S. (Principal Investigator)

2002-01-01

The effects of five tetracycline analogues, anhydrotetracycline, doxycycline, minocycline, oxytetracycline, and tetracycline, on Top10 promoter activity in NT1 tobacco tissue culture cells have been analysed. The concentration that repressed Top10 promoter activity, the level of transgene repression and the kinetics of transgene de-repression were determined for each analogue, and could not be predicted from in vitro binding affinity to the tetracycline repressor or from comparison with animal cells. Doxycycline had the most potent effect on the Top10 promoter and completely inhibited transgene expression at 4 nmol l(-1). Tetracycline was the most versatile of the analogues tested; tetracycline inhibited the Top10 promoter at 10 nmol l(-1) and was easily washed out to restore Top10-driven expression in 12-24 h. A study was also made of the suitability for plant research of a novel tetracycline analogue, GR33076X. In animal cells, GR33076X de-repressed Top10 promoter activity in the presence of inhibitory concentrations of anhydrotetracycline. In NT1, it is shown that GR 33076X can antagonize repression of the Top10 promoter in the presence of tetracycline, but not of anhydrotetracycline or of doxycycline. Different tetracycline analogues can therefore be used to regulate the Top10 promoter in plant cells and this property may be exploited in planning an optimum course of transgene regulation.

Citrus aurantium L. dry extracts promote C/ebpβ expression and improve adipocyte differentiation in 3T3-L1 cells.

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Raciti, Gregory Alexander; Fiory, Francesca; Campitelli, Michele; Desiderio, Antonella; Spinelli, Rosa; Longo, Michele; Nigro, Cecilia; Pepe, Giacomo; Sommella, Eduardo; Campiglia, Pietro; Formisano, Pietro; Beguinot, Francesco; Miele, Claudia

2018-01-01

Metabolic and/or endocrine dysfunction of the white adipose tissue (WAT) contribute to the development of metabolic disorders, such as Type 2 Diabetes (T2D). Therefore, the identification of products able to improve adipose tissue function represents a valuable strategy for the prevention and/or treatment of T2D. In the current study, we investigated the potential effects of dry extracts obtained from Citrus aurantium L. fruit juice (CAde) on the regulation of 3T3-L1 cells adipocyte differentiation and function in vitro. We found that CAde enhances terminal adipocyte differentiation of 3T3-L1 cells raising the expression of CCAAT/enhancer binding protein beta (C/Ebpβ), peroxisome proliferator activated receptor gamma (Pparγ), glucose transporter type 4 (Glut4) and fatty acid binding protein 4 (Fabp4). CAde improves insulin-induced glucose uptake of 3T3-L1 adipocytes, as well. A focused analysis of the phases occurring in the pre-adipocytes differentiation to mature adipocytes furthermore revealed that CAde promotes the early differentiation stage by up-regulating C/ebpβ expression at 2, 4 and 8 h post the adipogenic induction and anticipating the 3T3-L1 cell cycle entry and progression during mitotic clonal expansion (MCE). These findings provide evidence that the exposure to CAde enhances in vitro fat cell differentiation of pre-adipocytes and functional capacity of mature adipocytes, and pave the way to the development of products derived from Citrus aurantium L. fruit juice, which may improve WAT functional capacity and may be effective for the prevention and/or treatment of T2D.

Sox2 Promotes Malignancy in Glioblastoma by Regulating Plasticity and Astrocytic Differentiation

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Artem D. Berezovsky

2014-03-01

Full Text Available The high-mobility group–box transcription factor sex-determining region Y–box 2 (Sox2 is essential for the maintenance of stem cells from early development to adult tissues. Sox2 can reprogram differentiated cells into pluripotent cells in concert with other factors and is overexpressed in various cancers. In glioblastoma (GBM, Sox2 is a marker of cancer stemlike cells (CSCs in neurosphere cultures and is associated with the proneural molecular subtype. Here, we report that Sox2 expression pattern in GBM tumors and patient-derived mouse xenografts is not restricted to a small percentage of cells and is coexpressed with various lineage markers, suggesting that its expression extends beyond CSCs to encompass more differentiated neoplastic cells across molecular subtypes. Employing a CSC derived from a patient with GBM and isogenic differentiated cell model, we show that Sox2 knockdown in the differentiated state abolished dedifferentiation and acquisition of CSC phenotype. Furthermore, Sox2 deficiency specifically impaired the astrocytic component of a biphasic gliosarcoma xenograft model while allowing the formation of tumors with sarcomatous phenotype. The expression of genes associated with stem cells and malignancy were commonly downregulated in both CSCs and serum-differentiated cells on Sox2 knockdown. Genes previously shown to be associated with pluripontency and CSCs were only affected in the CSC state, whereas embryonic stem cell self-renewal genes and cytokine signaling were downregulated, and the Wnt pathway activated in differentiated Sox2-deficient cells. Our results indicate that Sox2 regulates the expression of key genes and pathways involved in GBM malignancy, in both cancer stemlike and differentiated cells, and maintains plasticity for bidirectional conversion between the two states, with significant clinical implications.

[Low-frequency pulsed electromagnetic fields promotes rat osteoblast differentiation in vitro through cAMP/PKA signal pathway].

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Fang, Qing-Qing; Li, Zhi-Zhong; Zhou, Jian; Shi, Wen-Gui; Yan, Juan-Li; Xie, Yan-Fang; Chen, Ke-Ming

2016-11-20

To study whether low-frequency pulsed electromagnetic fields promotes the differentiation of cultured rat osteoblasts through the cAMP/PKA signal pathway. Rat calvarial osteoblasts isolated by enzyme digestion were exposed to 50 Hz 0.6 mT low-frequency pulsed electromagnetic field for varying lengths of time, and the concentration of cAMP and levels of phosphorylated PKA in the cells were assayed. In cells treated with DDA to inhibit the activity of adenylate cyclase, the changes of ALP activity and transcription of osteogenic gene were detected after exposure to low-frequency pulsed electromagnetic field. The changes of osteogenic gene transcription and protein expression were tested in the osteoblasts pretreated with KT5720 in response to low-frequency pulsed electromagnetic field exposure. The intracellular cAMP concentration in the cells increased significantly at 20 min during exposure to low-frequency pulsed electromagnetic field, began to decrease at 40 min during the exposure, and increased again after a 2-h exposure; the same pattern of variation was also observed in p-PKA level. Application of DDA and KT5720 pretreatment both suppressed the increase in ALP activity and osteogenic gene transcription induced by electromagnetic field exposure. Low- frequency pulsed electromagnetic field exposure improves the differentiation of cultured rat osteoblasts by activating cAMP/PKA signal pathway.

Crosstalk between Wnt/β-catenin and estrogen receptor signaling synergistically promotes osteogenic differentiation of mesenchymal progenitor cells.

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Yanhong Gao

Full Text Available Osteogenic differentiation from mesenchymal progenitor cells (MPCs are initiated and regulated by a cascade of signaling events. Either Wnt/β-catenin or estrogen signaling pathway has been shown to play an important role in regulating skeletal development and maintaining adult tissue homeostasis. Here, we investigate the potential crosstalk and synergy of these two signaling pathways in regulating osteogenic differentiation of MPCs. We find that the activation of estrogen receptor (ER signaling by estradiol (E2 or exogenously expressed ERα in MPCs synergistically enhances Wnt3A-induced early and late osteogenic markers, as well as matrix mineralization. The E2 or ERα-mediated synergy can be effectively blocked by ERα antagonist tamoxifen. E2 stimulation can enhance endochondral ossification of Wnt3A-transduced mouse fetal limb explants. Furthermore, exogenously expressed ERα significantly enhances the maturity and mineralization of Wnt3A-induced subcutaneous and intramuscular ectopic bone formation. Mechanistically, we demonstrate that E2 does not exert any detectable effect on β-catenin/Tcf reporter activity. However, ERα expression is up-regulated within the first 48h in AdWnt3A-transduced MPCs, whereas ERβ expression is significantly inhibited within 24h. Moreover, the key enzyme for the biosynthesis of estrogens aromatase is modulated by Wnt3A in a biphasic manner, up-regulated at 24h but reduced after 48h. Our results demonstrate that, while ER signaling acts synergistically with Wnt3A in promoting osteogenic differentiation, Wnt3A may crosstalk with ER signaling by up-regulating ERα expression and down-regulating ERβ expression in MPCs. Thus, the signaling crosstalk and synergy between these two pathways should be further explored as a potential therapeutic approach to combating bone and skeletal disorders, such as fracture healing and osteoporosis.

Monomeric, porous type II collagen scaffolds promote chondrogenic differentiation of human bone marrow mesenchymal stem cells in vitro

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Tamaddon, M.; Burrows, M.; Ferreira, S. A.; Dazzi, F.; Apperley, J. F.; Bradshaw, A.; Brand, D. D.; Czernuszka, J.; Gentleman, E.

2017-03-01

Osteoarthritis (OA) is a common cause of pain and disability and is often associated with the degeneration of articular cartilage. Lesions to the articular surface, which are thought to progress to OA, have the potential to be repaired using tissue engineering strategies; however, it remains challenging to instruct cell differentiation within a scaffold to produce tissue with appropriate structural, chemical and mechanical properties. We aimed to address this by driving progenitor cells to adopt a chondrogenic phenotype through the tailoring of scaffold composition and physical properties. Monomeric type-I and type-II collagen scaffolds, which avoid potential immunogenicity associated with fibrillar collagens, were fabricated with and without chondroitin sulfate (CS) and their ability to stimulate the chondrogenic differentiation of human bone marrow-derived mesenchymal stem cells was assessed. Immunohistochemical analyses showed that cells produced abundant collagen type-II on type-II scaffolds and collagen type-I on type-I scaffolds. Gene expression analyses indicated that the addition of CS - which was released from scaffolds quickly - significantly upregulated expression of type II collagen, compared to type-I and pure type-II scaffolds. We conclude that collagen type-II and CS can be used to promote a more chondrogenic phenotype in the absence of growth factors, potentially providing an eventual therapy to prevent OA.

Health Promotion and Related Factors Among Korean Goose Mothers

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Chiyoung Cha, PhD, RN

2010-12-01

Conclusions: The findings of this study contributed to the body of knowledge of health promotion among international migrant populations by identifying the differential effects of social support, acculturation attitudes, and perceived family health for six areas of health promotion.

Group I Paks Promote Skeletal Myoblast Differentiation In Vivo and In Vitro

DEFF Research Database (Denmark)

Joseph, Giselle A; Lu, Min; Radu, Maria

2017-01-01

fusion in Drosophila We report that both Pak1 and Pak2 are activated during mammalian myoblast differentiation. One pathway of activation is initiated by N-cadherin ligation and involves the cadherin coreceptor Cdo with its downstream effector, Cdc42. Individual genetic deletion of Pak1 and Pak2 in mice....... Furthermore, primary myoblasts lacking Pak1 and Pak2 display delayed expression of myogenic differentiation markers and myotube formation. These results identify Pak1 and Pak2 as redundant regulators of myoblast differentiation in vitro and in vivo and as components of the promyogenic Ncad/Cdo/Cdc42 signaling...

An epithelial marker promoter induction screen identifies histone deacetylase inhibitors to restore epithelial differentiation and abolishes anchorage independence growth in cancers.

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Tang, H M; Kuay, K T; Koh, P F; Asad, M; Tan, T Z; Chung, V Y; Lee, S C; Thiery, J P; Huang, Ry-J

2016-01-01

Epithelial-mesenchymal transition (EMT), a crucial mechanism in development, mediates aggressiveness during carcinoma progression and therapeutic refractoriness. The reversibility of EMT makes it an attractive strategy in designing novel therapeutic approaches. Therefore, drug discovery pipelines for EMT reversal are in need to discover emerging classes of compounds. Here, we outline a pre-clinical drug screening platform for EMT reversal that consists of three phases of drug discovery and validation. From the Phase 1 epithelial marker promoter induction (EpI) screen on a library consisting of compounds being approved by Food and Drug Administration (FDA), Vorinostat (SAHA), a histone deacetylase inhibitor (HDACi), is identified to exert EMT reversal effects by restoring the expression of an epithelial marker, E-cadherin. An expanded screen on 41 HDACi further identifies 28 compounds, such as class I-specific HDACi Mocetinosat, Entinostat and CI994, to restore E-cadherin and ErbB3 expressions in ovarian, pancreatic and bladder carcinoma cells. Mocetinostat is the most potent HDACi to restore epithelial differentiation with the lowest concentration required for 50% induction of epithelial promoter activity (EpIC-50).The HDACi exerts paradoxical effects on EMT transcriptional factors such as SNAI and ZEB family and the effects are context-dependent in epithelial- and mesenchymal-like cells. In vitro functional studies further show that HDACi induced significant increase in anoikis and decrease in spheroid formation in ovarian and bladder carcinoma cells with mesenchymal features. This study demonstrates a robust drug screening pipeline for the discovery of compounds capable of restoring epithelial differentiation that lead to significant functional lethality.

Photobiomodulation Protects and Promotes Differentiation of C2C12 Myoblast Cells Exposed to Snake Venom.

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Luciana Miato Gonçalves Silva

Full Text Available Snakebites is a neglected disease and in Brazil is considered a serious health problem, with the majority of the snakebites caused by the genus Bothrops. Antivenom therapy and other first-aid treatments do not reverse local myonecrose which is the main sequel caused by the envenomation. Several studies have shown the effectiveness of low level laser (LLL therapy in reducing local myonecrosis induced by Bothropic venoms, however the mechanism involved in this effect is unknown. In this in vitro study, we aimed to analyze the effect of LLL irradiation against cytotoxicity induced by Bothrops jararacussu venom on myoblast C2C12 cells.C2C12 were utilized as a model target and were incubated with B. jararacussu venom (12.5 μg/mL and immediately irradiated with LLL at wavelength of red 685 nm or infrared 830 nm with energy density of 2.0, 4.6 and 7.0 J/cm2. Effects of LLL on cellular responses of venom-induced cytotoxicity were examined, including cell viability, measurement of cell damage and intra and extracellular ATP levels, expression of myogenic regulatory factors, as well as cellular differentiation.In non-irradiated cells, the venom caused a decrease in cell viability and a massive release of LDH and CK levels indicating myonecrosis. Infrared and red laser at all energy densities were able to considerably decrease venom-induced cytotoxicity. Laser irradiation induced myoblasts to differentiate into myotubes and this effect was accompanied by up regulation of MyoD and specially myogenin. Moreover, LLL was able to reduce the extracellular while increased the intracellular ATP content after venom exposure. In addition, no difference in the intensity of cytotoxicity was shown by non-irradiated and irradiated venom.LLL irradiation caused a protective effect on C2C12 cells against the cytotoxicity caused by B. jararacussu venom and promotes differentiation of these cells by up regulation of myogenic factors. A modulatory effect of ATP synthesis may

Taurine Protected Against the Impairments of Neural Stem Cell Differentiated Neurons Induced by Oxygen-Glucose Deprivation.

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Xiao, Bo; Liu, Huazhen; Gu, Zeyun; Liu, Sining; Ji, Cheng

2015-11-01

Cell transplantation of neural stem cells (NSCs) is a promising approach for neurological recovery both structurally and functionally. However, one big obstacle is to promote differentiation of NSCs into neurons and the followed maturation. In the present study, we aimed to investigate the protective effect of taurine on the differentiation of NSCs and subsequent maturation of their neuronal lineage, when exposed to oxygen-glucose deprivation (OGD). The results suggested that taurine (5-20 mM) promoted the viability and proliferation of NSCs, and it protected against 8 h of OGD induced impairments. Furthermore, 20 mM taurine promoted NSCs to differentiate into neurons after 7 days of culture, and it also protected against the suppressive impairments of 8 h of OGD. Consistently, taurine (20 mM) promoted the neurite sprouting and outgrowth of the NSC differentiated neurons after 14 days of differentiation, which were significantly inhibited by OGD (8 h). At D21, the mushroom spines and spine density were promoted or restored by 20 mM taurine. Taken together, the enhanced viability and proliferation of NSCs, more differentiated neurons and the promoted maturation of neurons by 20 mM taurine support its therapeutic application during stem cell therapy to enhance neurological recovery. Moreover, it protected against the impairments induced by OGD, which may highlight its role for a more direct therapeutic application especially in an ischemic stroke environment.

Differential action of glycoprotein hormones: significance in cancer progression.

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Govindaraj, Vijayakumar; Arya, Swathy V; Rao, A J

2014-02-01

Growth of multicellular organisms depends on maintenance of proper balance between proliferation and differentiation. Any disturbance in this balance in animal cells can lead to cancer. Experimental evidence is provided to conclude with special reference to the action of follicle-stimulating hormone (FSH) on Sertoli cells, and luteinizing hormone (LH) on Leydig cells that these hormones exert a differential action on their target cells, i.e., stimulate proliferation when the cells are in an undifferentiated state which is the situation with cancer cells and promote only functional parameters when the cell are fully differentiated. Hormones and growth factors play a key role in cell proliferation, differentiation, and apoptosis. There is a growing body of evidence that various tumors express some hormones at high levels as well as their cognate receptors indicating the possibility of a role in progression of cancer. Hormones such as LH, FSH, and thyroid-stimulating hormone have been reported to stimulate cell proliferation and act as tumor promoter in a variety of hormone-dependent cancers including gonads, lung, thyroid, uterus, breast, prostate, etc. This review summarizes evidence to conclude that these hormones are produced by some cancer tissues to promote their own growth. Also an attempt is made to explain the significance of the differential action of hormones in progression of cancer with special reference to prostate cancer.

Aubergine Controls Germline Stem Cell Self-Renewal and Progeny Differentiation via Distinct Mechanisms.

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Ma, Xing; Zhu, Xiujuan; Han, Yingying; Story, Benjamin; Do, Trieu; Song, Xiaoqing; Wang, Su; Zhang, Ying; Blanchette, Marco; Gogol, Madelaine; Hall, Kate; Peak, Allison; Anoja, Perera; Xie, Ting

2017-04-24

Piwi family protein Aubergine (Aub) maintains genome integrity in late germ cells of the Drosophila ovary through Piwi-associated RNA-mediated repression of transposon activities. Although it is highly expressed in germline stem cells (GSCs) and early progeny, it remains unclear whether it plays any roles in early GSC lineage development. Here we report that Aub promotes GSC self-renewal and GSC progeny differentiation. RNA-iCLIP results show that Aub binds the mRNAs encoding self-renewal and differentiation factors in cultured GSCs. Aub controls GSC self-renewal by preventing DNA-damage-induced Chk2 activation and by translationally controlling the expression of self-renewal factors. It promotes GSC progeny differentiation by translationally controlling the expression of differentiation factors, including Bam. Therefore, this study reveals a function of Aub in GSCs and their progeny, which promotes translation of self-renewal and differentiation factors by directly binding to its target mRNAs and interacting with translational initiation factors. Copyright © 2017 Elsevier Inc. All rights reserved.

Overexpression of osteoprotegerin promotes preosteoblast differentiation to mature osteoblasts

NARCIS (Netherlands)

Yu, Hongyou; de Vos, Paul; Ren, Yijin

OBJECTIVE: The hypothesis of the present study is that overexpression of osteoprotegerin (OPG) promotes preosteoblast maturation. MATERIALS AND METHODS: The preosteoblast cell line MC3T3-E1 was transfected with OPG overexpression. OPG expression was confirmed by enzyme-linked immunosorbent assay

Shoot Differentiation in Callus Cultures of Datura Innoxia

DEFF Research Database (Denmark)

Engvild, Kjeld Christensen

1973-01-01

promoted shoot differentiation. Gibberellic acid inhibited shoot formation weakly, but inhibited proper leaf blade formation. Root differentiation was rare. The callus cultures of Datura innoxia grew rapidly (100-fold in 4 weeks) on a slightly modified Murashige and Skoog medium (0.5 mg/l thiamin · HCl, p...

Surveillance for Secure Differentiation

DEFF Research Database (Denmark)

Hamilton, William B; Brickman, Joshua M

2017-01-01

The precise place and time where embryonic differentiation begins is regulated by regionalized signaling. In this issue of Cell Stem Cell, Wang et al. (2017) investigate how converging Wnt and Nodal signals promote mesendoderm through a p53, Wnt3 feed-forward loop, pointing to a mechanism by which...

TiO2 coating promotes human mesenchymal stem cell proliferation without the loss of their capacity for chondrogenic differentiation

International Nuclear Information System (INIS)

Kaitainen, Salla; Lappalainen, Reijo; Mähönen, Anssi J; J Lammi, Mikko; Qu, Chengjuan; Kröger, Heikki

2013-01-01

Human mesenchymal stem cells (hMSCs) are used in applications, which may require a large amount of cells; therefore, efficient expansion of the cells is desired. We studied whether TiO 2 coating on plastic cell culture dishes could promote proliferation of hMSCs without adverse effects in chondrogenic differentiation. TiO 2 -films were deposited on polystyrene dishes and glass coverslips using an ultrashort pulsed laser deposition technique. Human MSCs from three donors were expanded on them until 95% confluence, and the cells were evaluated by morphology, immunocytochemistry and quantitative RT-PCR (qRT-PCR). The chondrogenic differentiation in pellets was performed after cultivation on TiO 2 -coated dishes. Chondrogenesis was evaluated by histological staining of proteoglycans and type II collagen, and qRT-PCR. Human MSC-associated markers STRO-1, CD44, CD90 and CD146 did not change after expansion on TiO 2 -coated coverslips. However, the cell number after a 48h-culture period was significantly higher on TiO 2 -coated culture dishes. Importantly, TiO 2 coating caused no significant differences in the proteoglycan and type II collagen staining of the pellets, or the expression of chondrocyte-specific genes in the chondrogenesis assay. Thus, the proliferation of hMSCs could be significantly increased when cultured on TiO 2 -coated dishes without weakening their chondrogenic differentiation capacity. The transparency of TiO 2 -films allows easy monitoring of the cell growth and morphology under a phase-contrast microscope. (paper)

Growth/differentiation factor-15: prostate cancer suppressor or promoter?

Czech Academy of Sciences Publication Activity Database

Vaňhara, P.; Hampl, A.; Kozubík, Alois; Souček, Karel

2012-01-01

Roč. 15, č. 4 (2012), s. 320-328 ISSN 1365-7852 R&D Projects: GA MZd NS9600; GA MZd NS9956 Institutional research plan: CEZ:AV0Z50040702 Institutional support: RVO:68081707 Keywords : MACROPHAGE-INHIBITORY CYTOKINE-1 * GROWTH-DIFFERENTIATION FACTOR-15 * TGF-BETA SUPERFAMILY Subject RIV: BO - Biophysics Impact factor: 2.811, year: 2012

The C. elegans SoxC protein SEM-2 opposes differentiation factors to promote a proliferative blast cell fate in the postembryonic mesoderm

Science.gov (United States)

Tian, Chenxi; Shi, Herong; Colledge, Clark; Stern, Michael; Waterston, Robert; Liu, Jun

2011-01-01

The proper development of multicellular organisms requires precise regulation and coordination of cell fate specification, cell proliferation and differentiation. Abnormal regulation and coordination of these processes could lead to disease, including cancer. We have examined the function of the sole C. elegans SoxC protein, SEM-2, in the M lineage, which produces the postembryonic mesoderm. We found that SEM-2/SoxC is both necessary and sufficient to promote a proliferating blast cell fate, the sex myoblast fate, over a differentiated striated bodywall muscle fate. A number of factors control the specific expression of sem-2 in the sex myoblast precursors and their descendants. This includes direct control of sem-2 expression by a Hox-PBC complex. The crucial nature of the HOX/PBC factors in directly enhancing expression of this proliferative factor in the C. elegans M lineage suggests a possible more general link between Hox-PBC factors and SoxC proteins in regulating cell proliferation. PMID:21307099

ATF3 represses PPARγ expression and inhibits adipocyte differentiation

Energy Technology Data Exchange (ETDEWEB)

Jang, Min-Kyung; Jung, Myeong Ho, E-mail: jung0603@pusan.ac.kr

2014-11-07

Highlights: • ATF3 decrease the expression of PPARγ and its target gene in 3T3-L1 adipocytes. • ATF3 represses the promoter activity of PPARγ2 gene. • ATF/CRE (−1537/−1530) is critical for ATF3-mediated downregulation of PPARγ. • ATF3 binds to the promoter region containing the ATF/CRE. • ER stress inhibits adipocyte differentiation through downregulation of PPARγ by ATF3. - Abstract: Activating transcription factor 3 (ATF3) is a stress-adaptive transcription factor that mediates cellular stress response signaling. We previously reported that ATF3 represses CCAAT/enhancer binding protein α (C/EBPα) expression and inhibits 3T3-L1 adipocyte differentiation. In this study, we explored potential role of ATF3 in negatively regulating peroxisome proliferator activated receptor-γ (PPARγ). ATF3 decreased the expression of PPARγ and its target gene in 3T3-L1 adipocytes. ATF3 also repressed the activity of −2.6 Kb promoter of mouse PPARγ2. Overexpression of PPARγ significantly prevented the ATF3-mediated inhibition of 3T3-L1 differentiation. Transfection studies with 5′ deleted-reporters showed that ATF3 repressed the activity of −2037 bp promoter, whereas it did not affect the activity of −1458 bp promoter, suggesting that ATF3 responsive element is located between the −2037 and −1458. An electrophoretic mobility shift assay and chromatin immunoprecipitation assay demonstrated that ATF3 binds to ATF/CRE site (5′-TGACGTTT-3′) between −1537 and −1530. Mutation of the ATF/CRE site abrogated ATF3-mediated transrepression of the PPARγ2 promoter. Treatment with thapsigargin, endoplasmic reticulum (ER) stress inducer, increased ATF3 expression, whereas it decreased PPARγ expression. ATF3 knockdown significantly blocked the thapsigargin-mediated downregulation of PPARγ expression. Furthermore, overexpression of PPARγ prevented inhibition of 3T3-L1 differentiation by thapsigargin. Collectively, these results suggest that ATF3-mediated

Degree of Tissue Differentiation Dictates Susceptibility to BRAF-Driven Colorectal Cancer

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Kevin Tong

2017-12-01

Full Text Available Oncogenic mutations in BRAF are believed to initiate serrated colorectal cancers; however, the mechanisms of BRAF-driven colon cancer are unclear. We find that oncogenic BRAF paradoxically suppresses stem cell renewal and instead promotes differentiation. Correspondingly, tumor formation is inefficient in BRAF-driven mouse models of colon cancer. By reducing levels of differentiation via genetic manipulation of either of two distinct differentiation-promoting factors (Smad4 or Cdx2, stem cell activity is restored in BRAFV600E intestines, and the oncogenic capacity of BRAFV600E is amplified. In human patients, we observe that reduced levels of differentiation in normal tissue is associated with increased susceptibility to serrated colon tumors. Together, these findings help resolve the conditions necessary for BRAF-driven colon cancer initiation. Additionally, our results predict that genetic and/or environmental factors that reduce tissue differentiation will increase susceptibility to serrated colon cancer. These findings offer an opportunity to identify susceptible individuals by assessing their tissue-differentiation status.

Pluripotency factors in embryonic stem cells regulate differentiation into germ layers.

Science.gov (United States)

Thomson, Matt; Liu, Siyuan John; Zou, Ling-Nan; Smith, Zack; Meissner, Alexander; Ramanathan, Sharad

2011-06-10

Cell fate decisions are fundamental for development, but we do not know how transcriptional networks reorganize during the transition from a pluripotent to a differentiated cell state. Here, we asked how mouse embryonic stem cells (ESCs) leave the pluripotent state and choose between germ layer fates. By analyzing the dynamics of the transcriptional circuit that maintains pluripotency, we found that Oct4 and Sox2, proteins that maintain ESC identity, also orchestrate germ layer fate selection. Oct4 suppresses neural ectodermal differentiation and promotes mesendodermal differentiation; Sox2 inhibits mesendodermal differentiation and promotes neural ectodermal differentiation. Differentiation signals continuously and asymmetrically modulate Oct4 and Sox2 protein levels, altering their binding pattern in the genome, and leading to cell fate choice. The same factors that maintain pluripotency thus also integrate external signals and control lineage selection. Our study provides a framework for understanding how complex transcription factor networks control cell fate decisions in progenitor cells. Copyright © 2011 Elsevier Inc. All rights reserved.

Archaeal promoter architecture and mechanism of gene activation

DEFF Research Database (Denmark)

Peng, Nan; Ao, Xiang; Liang, Yun Xiang

2011-01-01

element named ara box directing arabinose-inducible expression and the basal promoter element TATA, serving as the binding site for the TATA-binding protein. Strikingly, these promoters possess a modular structure that allows an essentially inactive basal promoter to be strongly activated. The invoked...... mechanisms include TFB (transcription factor B) recruitment by the ara-box-binding factor to activate gene expression and modulation of TFB recruitment efficiency to yield differential gene expression....

Toward the Development of an Artificial Brain on a Micropatterned and Material-Regulated Biochip by Guiding and Promoting the Differentiation and Neurite Outgrowth of Neural Stem/Progenitor Cells.

Science.gov (United States)

Liu, Yung-Chiang; Lee, I-Chi; Lei, Kin Fong

2018-02-14

An in vitro model mimicking the in vivo environment of the brain must be developed to study neural communication and regeneration and to obtain an understanding of cellular and molecular responses. In this work, a multilayered neural network was successfully constructed on a biochip by guiding and promoting neural stem/progenitor cell differentiation and network formation. The biochip consisted of 3 × 3 arrays of cultured wells connected with channels. Neurospheroids were cultured on polyelectrolyte multilayer (PEM) films in the culture wells. Neurite outgrowth and neural differentiation were guided and promoted by the micropatterns and the PEM films. After 5 days in culture, a 3 × 3 neural network was constructed on the biochip. The function and the connections of the network were evaluated by immunocytochemistry and impedance measurements. Neurons were generated and produced functional and recyclable synaptic vesicles. Moreover, the electrical connections of the neural network were confirmed by measuring the impedance across the neurospheroids. The current work facilitates the development of an artificial brain on a chip for investigations of electrical stimulations and recordings of multilayered neural communication and regeneration.

Adipocyte differentiation-related protein promotes lipid accumulation in goat mammary epithelial cells.

Science.gov (United States)

Shi, H B; Yu, K; Luo, J; Li, J; Tian, H B; Zhu, J J; Sun, Y T; Yao, D W; Xu, H F; Shi, H P; Loor, J J

2015-10-01

Milk fat originates from the secretion of cytosolic lipid droplets (CLD) synthesized within mammary epithelial cells. Adipocyte differentiation-related protein (ADRP; gene symbol PLIN2) is a CLD-binding protein that is crucial for synthesis of mature CLD. Our hypothesis was that ADRP regulates CLD production and metabolism in goat mammary epithelial cells (GMEC) and thus plays a role in determining milk fat content. To understand the role of ADRP in ruminant milk fat metabolism, ADRP (PLIN2) was overexpressed or knocked down in GMEC using an adenovirus system. Immunocytochemical staining revealed that ADRP localized to the surface of CLD. Supplementation with oleic acid (OA) enhanced its colocalization with CLD surface and enhanced lipid accumulation. Overexpression of ADRP increased lipid accumulation and the concentration of triacylglycerol in GMEC. In contrast, morphological examination revealed that knockdown of ADRP decreased lipid accumulation even when OA was supplemented. This response was confirmed by the reduction in mass of cellular TG when ADRP was knocked down. The fact that knockdown of ADRP did not completely eliminate lipid accumulation at a morphological level in GMEC without OA suggests that some other compensatory factors may also aid in the process of CLD formation. The ADRP reversed the decrease of CLD accumulation induced by adipose triglyceride lipase. This is highly suggestive of ADRP promoting triacylglycerol stability within CLD by preventing access to adipose triglyceride lipase. Collectively, these data provide direct in vitro evidence that ADRP plays a key role in CLD formation and stability in GMEC. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

ATF3 inhibits adipocyte differentiation of 3T3-L1 cells

International Nuclear Information System (INIS)

Jang, Min Kyung; Kim, Cho Hee; Seong, Je Kyung; Jung, Myeong Ho

2012-01-01

Highlights: ► Overexpression of ATF3 inhibits adipocyte differentiation in 3T3-L1 cells. ► Overexpression of ATF3 represses C/EBPα expression. ► ATF3 directly binds to mouse C/EBPα promoter spanning from −1928 to −1907. ► ATF3 may play a role in hypoxia-mediated inhibition of adipocyte differentiation. -- Abstract: ATF3 is a stress-adaptive gene that regulates proliferation or apoptosis under stress conditions. However, the role of ATF3 is unknown in adipocyte cells. Therefore, in this study, we investigated the functional role of ATF3 in adipocytes. Both lentivirus-mediated overexpression of ATF3 and stably-overexpressed ATF3 inhibited adipocyte differentiation in 3T3-L1 cells, as revealed by decreased lipid staining with oil red staining and reduction in adipogenic genes. Thapsigargin treatment and overexpression of ATF3 decreased C/EBPα transcript and repressed the activity of the 3.6-kb mouse C/EBPα promoter, demonstrating that ATF3 downregulates C/EBPα expression. Transfection studies using mutant constructs containing 5′-deletions in the C/EBPα promoter revealed that a putative ATF/CRE element, GGATGTCA, is located between −1921 and −1914. Electrophoretic mobility shift assay and chromatin immunoprecipitation assay demonstrated that ATF3 directly binds to mouse C/EBPα promoter spanning from −1928 to −1907. Both chemical hypoxia-mimetics or physical hypoxia led to reduce the C/EBPα mRNA and repress the promoter activity of the C/EBPα gene, whereas increase ATF3 mRNA, suggesting that ATF3 may contribute to the inhibition of adipocyte differentiation in hypoxia through downregulation of C/EBPα expression. Collectively, these results demonstrate that ATF3 represses the C/EBPα gene, resulting in inhibition of adipocyte differentiation, and thus plays a role in hypoxia-mediated inhibition of adipocyte differentiation.

Improving Sales Promotion of a Beverage Company in Nigeria

OpenAIRE

Abdulrauf, Abdullahi

2012-01-01

Promotion campaign is probably the most important aspect of the four marketing-mix elements—Price, Place, Product and Promotion— that are used to solve companies’ problems and gain competitive advantage if well implemented. This important element of marketing-mix involves personal selling, advertisement, sales promotion and public relations. Meanwhile, the ultimate objectives of promotion are to create awareness, provide information about goods and services, and differentiate a product fro...

Effect of organization-level variables on differential employee participation in 10 federal worksite health promotion programs.

Science.gov (United States)

Crump, C E; Earp, J A; Kozma, C M; Hertz-Picciotto, I

1996-05-01

Guided by a conceptual model, the authors used both qualitative data (e.g., individual interviews, focus groups) and quantitative data from an employee survey (N = 3,388) in 10 federal agencies to investigate whether organization context and implementation process affected participation in worksite health promotion and disease prevention (HPDP) activities among demographic subgroups. Overall, employees on average participated in fewer than two agency-supported health-related activities per year (17% in fitness, 40% in health risk assessment activities). Employees participated more where coworkers endorsed such programs. Minority employees and employees in lower level positions were more likely to participate in fitness activities when organizations had a more comprehensive program structure, engaged in more marketing strategies, gave time off to employees to participate, or had on-site facilities. Management support for the program was related to participation by employees who were male, white, and had upper level positions. The data supported the proposed model; also confirmed was two predicted relationships between model constructs, which provided a better understanding of differential participation by employee groups.

Diclofenac and triamcinolone acetonide impair tenocytic differentiation and promote adipocytic differentiation of mesenchymal stem cells

OpenAIRE

Fredriksson, Maritha; Li, Yan; St?lman, Anders; Haldos?n, Lars-Arne; Fell?nder-Tsai, Li

2013-01-01

Background Tendinopathies are often empirically treated with oral/topical nonsteroidal anti-inflammatory medications and corticosteroid injections despite their unclear effects on tendon regeneration. Recent studies indicate that tendon progenitors exhibit stem cell-like properties, i.e., differentiation to osteoblasts, adipocytes, and chondrocytes, in addition to tenocytes. Our present study aims at understanding the effects of triamcinolone acetonide and diclofenac on tenocytic differentiat...

Regional differences in gene expression and promoter usage in aged human brains

KAUST Repository

Pardo, Luba M.

2013-02-19

To characterize the promoterome of caudate and putamen regions (striatum), frontal and temporal cortices, and hippocampi from aged human brains, we used high-throughput cap analysis of gene expression to profile the transcription start sites and to quantify the differences in gene expression across the 5 brain regions. We also analyzed the extent to which methylation influenced the observed expression profiles. We sequenced more than 71 million cap analysis of gene expression tags corresponding to 70,202 promoter regions and 16,888 genes. More than 7000 transcripts were differentially expressed, mainly because of differential alternative promoter usage. Unexpectedly, 7% of differentially expressed genes were neurodevelopmental transcription factors. Functional pathway analysis on the differentially expressed genes revealed an overrepresentation of several signaling pathways (e.g., fibroblast growth factor and wnt signaling) in hippocampus and striatum. We also found that although 73% of methylation signals mapped within genes, the influence of methylation on the expression profile was small. Our study underscores alternative promoter usage as an important mechanism for determining the regional differences in gene expression at old age.

Leptin promotes wound healing in the skin.

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Susumu Tadokoro

Full Text Available Leptin, a 16 kDa anti-obesity hormone, exhibits various physiological properties. Interestingly, skin wound healing was proven to delay in leptin-deficient ob/ob mice. However, little is known on the mechanisms of this phenomenon. In this study, we attempted to elucidate a role of leptin in wound healing of skin.Immunohistochemical analysis was performed to confirm the expression of the leptin receptor (Ob-R in human and mouse skin. Leptin was topically administered to chemical wounds created in mouse back skin along with sustained-release absorbable hydrogel. The process of wound repair was histologically observed and the area of ulceration was measured over time. The effect of leptin on the proliferation, differentiation and migration of human epidermal keratinocytes was investigated.Ob-R was expressed in epidermal cells of human and mouse skin. Topical administration of leptin significantly promoted wound healing. Histological analysis showed more blood vessels in the dermal connective tissues in the leptin-treated group. The proliferation, differentiation/function and migration of human epidermal keratinocytes were enhanced by exogenous leptin.Topically administered leptin was proven to promote wound healing in the skin by accelerating proliferation, differentiation/function and migration of epidermal keratinocytes and enhancing angiogenesis around the wounded area. These results strongly suggest that topical administration of leptin may be useful as a treatment to promote wound healing in the skin.

S100A16 promotes differentiation and contributes to a less aggressive tumor phenotype in oral squamous cell carcinoma

International Nuclear Information System (INIS)

Sapkota, Dipak; Bruland, Ove; Parajuli, Himalaya; Osman, Tarig A.; Teh, Muy-Teck; Johannessen, Anne C.; Costea, Daniela Elena

2015-01-01

-expression. These functional effects were associated with concomitant down-regulation of self-renewal (Bmi-1 and Oct 4A) and invasion related (MMP1 and MMP9) molecules. S100A16 over-expression also suppressed tumorigenesis of H357 cells in a mouse xenograft model and the resulting tumor xenografts displayed features/expression of increased differentiation and reduced proliferation/self-renewal. These results indicate that S100A16 is a differentiation promoting protein and might function as a tumor suppressor in OSCC. The online version of this article (doi:10.1186/s12885-015-1622-1) contains supplementary material, which is available to authorized users

Micro-Topographies Promote Late Chondrogenic Differentiation Markers in the ATDC5 Cell Line

NARCIS (Netherlands)

Le, Bach Q.; Vasilevich, Aliaksei; Vermeulen, Steven; Hulshof, Frits; Stamatialis, Dimitrios F.; Van Blitterswijk, Clemens A.; De Boer, Jan

2017-01-01

Chemical and mechanical cues are well-established influencers of in vitro chondrogenic differentiation of ATDC5 cells. Here, we investigate the role of topographical cues in this differentiation process, a study not been explored before. Previously, using a library of surface micro-topographies we

Differential tissue distribution, developmental programming, estrogen regulation and promoter characteristics of cyp19 genes in teleost fish.

Science.gov (United States)

Callard, G V; Tchoudakova, A V; Kishida, M; Wood, E

2001-12-01

Teleost fish are characterized by exceptionally high levels of brain estrogen biosynthesis when compared to the brains of other vertebrates or to the ovaries of the same fish. Goldfish (Carassius auratus) and zebrafish (Danio rerio) have utility as complementary models for understanding the molecular basis and functional significance of exaggerated neural estrogen biosynthesis. Multiple cytochrome P450 aromatase (P450arom) cDNAs that derive from separate gene loci (cyp19a and cyp19b) are differentially expressed in brain (P450aromB>A) and ovary (P450aromA>B) and have a different developmental program (B>A) and response to estrogen upregulation (B only). As measured by increased P450aromB mRNA, a functional estrogen response system is first detected 24-48 h post-fertilization (hpf), consistent with the onset of estrogen receptor (ER) expression (alpha, beta, and gamma). The 5'-flanking region of the cyp19b gene has a TATA box, two estrogen response elements (EREs), an ERE half-site (ERE1/2), a nerve growth factor inducible-B protein (NGFI-B)/Nur77 responsive element (NBRE) binding site, and a sequence identical to the zebrafish GATA-2 gene neural specific enhancer. The cyp19a promoter region has TATA and CAAT boxes, a steroidogenic factor-1 (SF-1) binding site, and two aryl hydrocarbon receptor (AhR)/AhR nuclear translocator factor (ARNT) binding motifs. Both genes have multiple potential SRY/SOX binding sites (16 and 8 in cyp19b and cyp19a, respectively). Luciferase reporters have basal promoter activity in GH3 cells, but differences (a>b) are opposite to fish pituitary (b>a). When microinjected into fertilized zebrafish eggs, a cyp19b promoter-driven green fluorescent protein (GFP) reporter (but not cyp19a) is expressed in neurons of 30-48 hpf embryos, most prominently in retinal ganglion cells (RGCs) and their projections to optic tectum. Further studies are required to identify functionally relevant cis-elements and cellular factors, and to determine the

Investigation of modified platelet-rich plasma (mPRP in promoting the proliferation and differentiation of dental pulp stem cells from deciduous teeth

Directory of Open Access Journals (Sweden)

J. Wen

2016-01-01

Full Text Available Stem cells from human exfoliated deciduous teeth (SHEDs have great potential to treat various dental-related diseases in regenerative medicine. They are usually maintained with 10% fetal bovine serum (FBS in vitro. Modified platelet-rich plasma (mPRP would be a safe alternative to 10% FBS during SHEDs culture. Therefore, our study aimed to compare the proliferation and differentiation of SHEDs cultured in mPRP and FBS medium to explore an optimal concentration of mPRP for SHEDs maintenance. Platelets were harvested by automatic blood cell analyzer and activated by repeated liquid nitrogen freezing and thawing. The platelet-related cytokines were examined and analyzed by ELISA. SHEDs were extracted and cultured with different concentrations of mPRP or 10% FBS medium. Alkaline phosphatase (ALP activity was measured. Mineralization factors, RUNX2 and OCN, were measured by real-time PCR. SHEDs were characterized with mesenchymal stem cells (MSCs markers including vimentin, CD44, and CD105. mPRP at different concentrations (2, 5, 10, and 20% enhanced the growth of SHEDs. Moreover, mPRP significantly stimulated ALP activity and promoted expression of RUNX2 and OCN compared with 10% FBS. mPRP could efficiently facilitate proliferation and differentiation of SHEDs, and 2% mPRP would be an optimal substitute for 10% FBS during SHEDs expansion and differentiation in clinical scale manufacturing.

Vasa promotes Drosophila germline stem cell differentiation by activating mei-P26 translation by directly interacting with a (U)-rich motif in its 3' UTR.

Science.gov (United States)

Liu, Niankun; Han, Hong; Lasko, Paul

2009-12-01

Vasa (Vas) is a DEAD-box RNA-binding protein required in Drosophila at several steps of oogenesis and for primordial germ cell (PGC) specification. Vas associates with eukaryotic initiation factor 5B (eIF5B), and this interaction has been implicated in translational activation of gurken mRNA in the oocyte. Vas is expressed in all ovarian germline cells, and aspects of the vas-null phenotype suggest a function in regulating the balance between germline stem cells (GSCs) and their fate-restricted descendants. We used a biochemical approach to recover Vas-associated mRNAs and obtained mei-P26, whose product represses microRNA activity and promotes GSC differentiation. We found that vas and mei-P26 mutants interact, and that mei-P26 translation is substantially reduced in vas mutant cells. In vitro, Vas protein bound specifically to a (U)-rich motif in the mei-P26 3' untranslated region (UTR), and Vas-dependent regulation of GFP-mei-P26 transgenes in vivo was dependent on the same (U)-rich 3' UTR domain. The ability of Vas to activate mei-P26 expression in vivo was abrogated by a mutation that greatly reduces its interaction with eIF5B. Taken together, our data support the conclusion that Vas promotes germ cell differentiation by directly activating mei-P26 translation in early-stage committed cells.

Induction of autophagy is essential for monocyte-macrophage differentiation

OpenAIRE

Zhang, Yan; Morgan, Michael J.; Chen, Kun; Choksi, Swati; Liu, Zheng-gang

2012-01-01

Monocytes are programmed to undergo apoptosis in the absence of stimulation. Stimuli that promote monocyte-macrophage differentiation not only cause cellular changes, but also prevent the default apoptosis of monocytes. In the present study, we demonstrate that autophagy is induced when monocytes are triggered to differentiate and that the induction of autophagy is pivotal for the survival and differentiation of monocytes. We also show that inhibition of autophagy results in apoptosis of cell...

A Noninvasive In Vitro Monitoring System Reporting Skeletal Muscle Differentiation.

Science.gov (United States)

Öztürk-Kaloglu, Deniz; Hercher, David; Heher, Philipp; Posa-Markaryan, Katja; Sperger, Simon; Zimmermann, Alice; Wolbank, Susanne; Redl, Heinz; Hacobian, Ara

2017-01-01

Monitoring of cell differentiation is a crucial aspect of cell-based therapeutic strategies depending on tissue maturation. In this study, we have developed a noninvasive reporter system to trace murine skeletal muscle differentiation. Either a secreted bioluminescent reporter (Metridia luciferase) or a fluorescent reporter (green fluorescent protein [GFP]) was placed under the control of the truncated muscle creatine kinase (MCK) basal promoter enhanced by variable numbers of upstream MCK E-boxes. The engineered pE3MCK vector, coding a triple tandem of E-Boxes and the truncated MCK promoter, showed twentyfold higher levels of luciferase activation compared with a Cytomegalovirus (CMV) promoter. This newly developed reporter system allowed noninvasive monitoring of myogenic differentiation in a straining bioreactor. Additionally, binding sequences of endogenous microRNAs (miRNAs; seed sequences) that are known to be downregulated in myogenesis were ligated as complementary seed sequences into the reporter vector to reduce nonspecific signal background. The insertion of seed sequences improved the signal-to-noise ratio up to 25% compared with pE3MCK. Due to the highly specific, fast, and convenient expression analysis for cells undergoing myogenic differentiation, this reporter system provides a powerful tool for application in skeletal muscle tissue engineering.

The regulation of mitochondrial transcription factor A (Tfam) expression during skeletal muscle cell differentiation.

Science.gov (United States)

Collu-Marchese, Melania; Shuen, Michael; Pauly, Marion; Saleem, Ayesha; Hood, David A

2015-05-19

The ATP demand required for muscle development is accommodated by elevations in mitochondrial biogenesis, through the co-ordinated activities of the nuclear and mitochondrial genomes. The most important transcriptional activator of the mitochondrial genome is mitochondrial transcription factor A (Tfam); however, the regulation of Tfam expression during muscle differentiation is not known. Thus, we measured Tfam mRNA levels, mRNA stability, protein expression and localization and Tfam transcription during the progression of muscle differentiation. Parallel 2-fold increases in Tfam protein and mRNA were observed, corresponding with 2-3-fold increases in mitochondrial content. Transcriptional activity of a 2051 bp promoter increased during this differentiation period and this was accompanied by a 3-fold greater Tfam mRNA stabilization. Interestingly, truncations of the promoter at 1706 bp, 978 bp and 393 bp promoter all exhibited 2-3-fold higher transcriptional activity than the 2051 bp construct, indicating the presence of negative regulatory elements within the distal 350 bp of the promoter. Activation of AMP kinase augmented Tfam transcription within the proximal promoter, suggesting the presence of binding sites for transcription factors that are responsive to cellular energy state. During differentiation, the accumulating Tfam protein was progressively distributed to the mitochondrial matrix where it augmented the expression of mtDNA and COX (cytochrome c oxidase) subunit I, an mtDNA gene product. Our data suggest that, during muscle differentiation, Tfam protein levels are regulated by the availability of Tfam mRNA, which is controlled by both transcription and mRNA stability. Changes in energy state and Tfam localization also affect Tfam expression and action in differentiating myotubes. © 2015 Authors.

Understanding the molecular basis of plant growth promotional effect of Pseudomonas fluorescens on rice through protein profiling.

Science.gov (United States)

Kandasamy, Saveetha; Loganathan, Karthiba; Muthuraj, Raveendran; Duraisamy, Saravanakumar; Seetharaman, Suresh; Thiruvengadam, Raguchander; Ponnusamy, Balasubramanian; Ramasamy, Samiyappan

2009-12-24

Plant Growth Promoting Rhizobacteria (PGPR), Pseudomonas fluorescens strain KH-1 was found to exhibit plant growth promotional activity in rice under both in-vitro and in-vivo conditions. But the mechanism underlying such promotional activity of P. fluorescens is not yet understood clearly. In this study, efforts were made to elucidate the molecular responses of rice plants to P. fluorescens treatment through protein profiling. Two-dimensional polyacrylamide gel electrophoresis strategy was adopted to identify the PGPR responsive proteins and the differentially expressed proteins were analyzed by mass spectrometry. Priming of P. fluorescens, 23 different proteins found to be differentially expressed in rice leaf sheaths and MS analysis revealed the differential expression of some important proteins namely putative p23 co-chaperone, Thioredoxin h- rice, Ribulose-bisphosphate carboxylase large chain precursor, Nucleotide diPhosphate kinase, Proteosome sub unit protein and putative glutathione S-transferase protein. Functional analyses of the differential proteins were reported to be directly or indirectly involved in growth promotion in plants. Thus, this study confirms the primary role of PGPR strain KH-1 in rice plant growth promotion.

PHLOEM PROMOTERS IN TRANSGENIC SWEET ORANGE ARE DIFFERENTIALLY TRIGGERED BY Candidatus Liberibacter asiaticus

Directory of Open Access Journals (Sweden)

LUZIA YURIKO MIYATA

Full Text Available ABSTRACT The use of promoters preferentially expressed in specific plant tissues is a desirable strategy to search for resistance for pathogens that colonize these tissues. The bacterium Candidatus Liberibacter asiaticus (Las, associated with huanglongbing disease (HLB of citrus, colonizes phloem vessels. Some promoters, besides conferring tissue-specific expression, can also respond to the presence of the pathogen. The objective of the present study was to verify if the presence of Las could modulate the activation of the phloem-specific promoters AtPP2 (Arabidopsis thaliana phloem protein 2, AtSUC2 (A. thaliana sucrose transporter 2 and CsPP2 ( pCitrus phloemrotein 2, known to be expressed in Citrus sinensis phloem. ‘Hamlin’ sweet orange plants (Citrus sinensis L. Osbeck transformed with the uidA (GUS reporter gene under the control of AtPP2, AtSUC2 and CsPP2 promoters were infected to evaluate the interdependence between transgene expression and the concentration of Las. Plants were inoculated with Las by Diaphorina citri and eighteen months later, bacterial concentration and uidA expression were determined by qPCR and RT-qPCR, respectively. Reporter gene expression driven by AtSUC2 promoter was strongly and positively correlated with Las concentration. Therefore, this promoter combines desirable features of both tissue-specificity and pathogen-inducibility for the production of transgenic plants tolerant to Las.

GDNF/GFRα1 Complex Abrogates Self-Renewing Activity of Cortical Neural Precursors Inducing Their Differentiation

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Antonela Bonafina

2018-03-01

Full Text Available Summary: The balance between factors leading to proliferation and differentiation of cortical neural precursors (CNPs determines the correct cortical development. In this work, we show that GDNF and its receptor GFRα1 are expressed in the neocortex during the period of cortical neurogenesis. We show that the GDNF/GFRα1 complex inhibits the self-renewal capacity of mouse CNP cells induced by fibroblast growth factor 2 (FGF2, promoting neuronal differentiation. While GDNF leads to decreased proliferation of cultured cortical precursor cells, ablation of GFRα1 in glutamatergic cortical precursors enhances its proliferation. We show that GDNF treatment of CNPs promoted morphological differentiation even in the presence of the self-renewal-promoting factor, FGF2. Analysis of GFRα1-deficient mice shows an increase in the number of cycling cells during cortical development and a reduction in dendrite development of cortical GFRα1-expressing neurons. Together, these results indicate that GDNF/GFRα1 signaling plays an essential role in regulating the proliferative condition and the differentiation of cortical progenitors. : In this article, Ledda and colleagues show that GDNF acting through its receptor GFRα1 plays a critical role in the maturation of cortical progenitors by counteracting FGF2 self-renewal activity on neural stem cells and promoting neuronal differentiation. Keywords: GDNF, GFRα1, cortical precursors, proliferation, postmitotic neurons, neuronal differentiation

Correlates of in-store promotions for beer: differential effects of market and product characteristics.

Science.gov (United States)

Bray, Jeremy W; Loomis, Brett; Engelen, Mark

2007-03-01

We estimated the strength and direction of the association between product characteristics (beer type, package size, and brand name) and market-area socioeconomic characteristics, and promoted sales of beer in grocery stores. Supermarket scanner data from 64 market areas across the United States over 5 years were used to estimate regression models of the share of beer sales that are promoted, controlling for beer price, packaging, and type; and for market-level age, race/ethnicity, income, unemployment rate, and percentage of the population living in an alcohol control state. Large-volume units, such as 144-oz and 288-oz packages, are more likely to be promoted than smaller package sizes. Malt-liquor beverages are less likely to be promoted than non-malt-liquor beverages. Age, race/ethnicity, income, and geographic location of the market area are not significantly related to promoted beer sales. Marketing research has shown that in-store merchandising and promotions can substantially increase beer sales and that purchasing large package sizes may increase total consumption. Our results suggest that high levels of promoted sales for large-volume beer packages may result in increased beer consumption.

International Conference on Differential and Difference Equations with Applications

CERN Document Server

Došlá, Zuzana; Došlý, Ondrej; Kloeden, Peter

2016-01-01

Aimed at the community of mathematicians working on ordinary and partial differential equations, difference equations, and functional equations, this book contains selected papers based on the presentations at the International Conference on Differential and Difference Equations and Applications (ICDDEA) 2015, dedicated to the memory of Professor Georg Sell. Contributions include new trends in the field of differential and difference equations, applications of differential and difference equations, as well as high-level survey results. The main aim of this recurring conference series is to promote, encourage, cooperate, and bring together researchers in the fields of differential and difference equations. All areas of differential and difference equations are represented, with special emphasis on applications.

BAMBI Promotes C2C12 Myogenic Differentiation by Enhancing Wnt/β-Catenin Signaling

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Qiangling Zhang

2015-08-01

Full Text Available Bone morphogenic protein and activin membrane-bound inhibitor (BAMBI is regarded as an essential regulator of cell proliferation and differentiation that represses transforming growth factor-β and enhances Wnt/β-catenin signaling in various cell types. However, its role in skeletal muscle remains largely unknown. In the current study, we found that the expression level of BAMBI peaked in the early differentiation phase of the C2C12 rodent myoblast cell line. Knockdown of BAMBI via siRNA inhibited C2C12 differentiation, indicated by repressed MyoD, MyoG, and MyHC expression as well as reductions in the differentiation and fusion indices. BAMBI knockdown reduced the activity of Wnt/β-catenin signaling, as characterized by the decreased nuclear translocation of β-catenin and the lowered transcription of Axin2, which is a well-documented target gene of the Wnt/β-catenin signaling pathway. Furthermore, treatment with LiCl, an activator of Wnt/β-catenin signaling, rescued the reduction in C2C12 differentiation caused by BAMBI siRNA. Taken together, our data suggest that BAMBI is required for normal C2C12 differentiation, and that its role in myogenesis is mediated by the Wnt/β-catenin pathway.

Inhibitor of PI3K/Akt Signaling Pathway Small Molecule Promotes Motor Neuron Differentiation of Human Endometrial Stem Cells Cultured on Electrospun Biocomposite Polycaprolactone/Collagen Scaffolds.

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Ebrahimi-Barough, Somayeh; Hoveizi, Elham; Yazdankhah, Meysam; Ai, Jafar; Khakbiz, Mehrdad; Faghihi, Faezeh; Tajerian, Roksana; Bayat, Neda

2017-05-01

Small molecules as useful chemical tools can affect cell differentiation and even change cell fate. It is demonstrated that LY294002, a small molecule inhibitor of phosphatidylinositol 3-kinase (PI3K)/Akt signal pathway, can inhibit proliferation and promote neuronal differentiation of mesenchymal stem cells (MSCs). The purpose of this study was to investigate the differentiation effect of Ly294002 small molecule on the human endometrial stem cells (hEnSCs) into motor neuron-like cells on polycaprolactone (PCL)/collagen scaffolds. hEnSCs were cultured in a neurogenic inductive medium containing 1 μM LY294002 on the surface of PCL/collagen electrospun fibrous scaffolds. Cell attachment and viability of cells on scaffolds were characterized by scanning electron microscope (SEM) and 3-(4,5-dimethylthiazoyl-2-yl)2,5-diphenyltetrazolium bromide (MTT) assay. The expression of neuron-specific markers was assayed by real-time PCR and immunocytochemistry analysis after 15 days post induction. Results showed that attachment and differentiation of hEnSCs into motor neuron-like cells on the scaffolds with Ly294002 small molecule were higher than that of the cells on tissue culture plates as control group. In conclusion, PCL/collagen electrospun scaffolds with Ly294002 have potential for being used in neural tissue engineering because of its bioactive and three-dimensional structure which enhances viability and differentiation of hEnSCs into neurons through inhibition of the PI3K/Akt pathway. Thus, manipulation of this pathway by small molecules can enhance neural differentiation.

Overexpression of Cardiac-Specific Kinase TNNI3K Promotes Mouse Embryonic Stem Cells Differentiation into Cardiomyocytes.

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Wang, Yin; Wang, Shi-Qiang; Wang, Li-Peng; Yao, Yu-Hong; Ma, Chun-Yan; Ding, Jin-Feng; Ye, Jue; Meng, Xian-Min; Li, Jian-Jun; Xu, Rui-Xia

2017-01-01

Backgroud/Aims: The biological function of cardiac troponin I-interacting kinase (TNNI3K), a cardiac-specific functional kinase, is largely unknown. We investigated the effect of human TNNI3K (hTNNI3K) on the differentiation of mouse embryonic stem cells (mESCs) into cardiomyocytes. First, the time-space expression of endogenous Tnni3k was detected by real-time polymerase chain reaction (PCR) and western blotting at 16 different time-points over a period of 28 days. Further, action potentials and calcium current with/without 5 µM nifedipine were measured by patch clamp for mESC-derived cardiomyocytes. HTNNI3K and mouse-derived siRNA were transfected into mESC using lentivirus vector to induce hTNNI3K overexpression and knock-down, respectively. The number of troponin-T (cTnT) positive cells was greater in the group with TNNI3K overexpression as compared to that in control group, while less such cells were detected in the mTnni3k knock-down group as evaluated on flow cytometry (FCM) and ImageXpress Micro system. After upregulation of connexin43, cardiac troponin-I (Ctni), Ctni, Gata4 were detected in mESCs with TNNI3K overexpression; however, overexpression of α-Actinin and Mlc2v was not detected. Interestingly, Ctnt, connexin40 and connexin45, the markers of ventricular, atrial, and pacemaker cells, respectively, were detected in by real-time PCR in TNNI3K overexpression group. our study indicated that TNNI3K overexpression promoted mESC differentiating into beating cardiomyocytes and induced up-regulating expression of cTnT by PKCε signal pathway, which suggested a modulation of TNNI3K activity as a potential therapeutic approach for ischemic cardiac disease. © 2017 The Author(s) Published by S. Karger AG, Basel.

Pharmacological activation of aldehyde dehydrogenase 2 promotes osteoblast differentiation via bone morphogenetic protein-2 and induces bone anabolic effect

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Mittal, Monika; Pal, Subhashis; China, Shyamsundar Pal; Porwal, Konica [Division of Endocrinology and Centre for Research in Anabolic Skeletal Targets in Health and Illness (ASTHI), CSIR-Central Drug Research Institute, Lucknow 226031 (India); Dev, Kapil [Division of Medicinal and Process Chemistry, CSIR-Central Drug Research Institute, Lucknow 226031 (India); Shrivastava, Richa [Division of Toxicology, CSIR-Central Drug Research Institute, Lucknow 226031 (India); Raju, Kanumuri Siva Rama; Rashid, Mamunur [Pharmaceutics Division, CSIR-Central Drug Research Institute, Lucknow 226031 (India); Trivedi, Arun Kumar; Sanyal, Sabyasachi [Biochemistry Division, CSIR-Central Drug Research Institute, Lucknow 226031 (India); Wahajuddin, Muhammad [Pharmaceutics Division, CSIR-Central Drug Research Institute, Lucknow 226031 (India); Bhaduria, Smrati [Division of Toxicology, CSIR-Central Drug Research Institute, Lucknow 226031 (India); Maurya, Rakesh [Division of Medicinal and Process Chemistry, CSIR-Central Drug Research Institute, Lucknow 226031 (India); Chattopadhyay, Naibedya, E-mail: n_chattopadhyay@cdri.res.in [Division of Endocrinology and Centre for Research in Anabolic Skeletal Targets in Health and Illness (ASTHI), CSIR-Central Drug Research Institute, Lucknow 226031 (India)

2017-02-01

Aldehyde dehydrogenases (ALDHs) are a family of enzymes involved in detoxifying aldehydes. Previously, we reported that an ALDH inhibitor, disulfiram caused bone loss in rats and among ALDHs, osteoblast expressed only ALDH2. Loss-of-function mutation in ALDH2 gene is reported to cause bone loss in humans which suggested its importance in skeletal homeostasis. We thus studied whether activating ALDH2 by N-(1, 3-benzodioxol-5-ylmethyl)-2, 6-dichlorobenzamide (alda-1) had osteogenic effect. We found that alda-1 increased and acetaldehyde decreased the differentiation of rat primary osteoblasts and expressions of ALDH2 and bone morphogenetic protein-2 (BMP-2). Silencing ALDH2 in osteoblasts abolished the alda-1 effects. Further, alda-1 attenuated the acetaldehyde-induced lipid-peroxidation and oxidative stress. BMP-2 is essential for bone regeneration and alda-1 increased its expression in osteoblasts. We then showed that alda-1 (40 mg/kg dose) augmented bone regeneration at the fracture site with concomitant increase in BMP-2 protein compared with control. The osteogenic dose (40 mg/kg) of alda-1 attained a bone marrow concentration that was stimulatory for osteoblast differentiation, suggesting that the tissue concentration of alda-1 matched its pharmacologic effect. In addition, alda-1 promoted modeling-directed bone growth and peak bone mass achievement, and increased bone mass in adult rats which reiterated its osteogenic effect. In osteopenic ovariectomized (OVX) rats, alda-1 reversed trabecular osteopenia with attendant increase in serum osteogenic marker (procollagen type I N-terminal peptide) and decrease in oxidative stress. Alda-1 has no effect on liver and kidney function. We conclude that activating ALDH2 by alda-1 had an osteoanabolic effect involving increased osteoblastic BMP-2 production and decreased OVX-induced oxidative stress. - Highlights: • Alda-1 induced osteoblast differentiation that involved upregulation of ALDH2 and BMP-2 • Alda-1

Understanding the molecular basis of plant growth promotional effect of Pseudomonas fluorescens on rice through protein profiling

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Thiruvengadam Raguchander

2009-12-01

Full Text Available Abstract Background Plant Growth Promoting Rhizobacteria (PGPR, Pseudomonas fluorescens strain KH-1 was found to exhibit plant growth promotional activity in rice under both in-vitro and in-vivo conditions. But the mechanism underlying such promotional activity of P. fluorescens is not yet understood clearly. In this study, efforts were made to elucidate the molecular responses of rice plants to P. fluorescens treatment through protein profiling. Two-dimensional polyacrylamide gel electrophoresis strategy was adopted to identify the PGPR responsive proteins and the differentially expressed proteins were analyzed by mass spectrometry. Results Priming of P. fluorescens, 23 different proteins found to be differentially expressed in rice leaf sheaths and MS analysis revealed the differential expression of some important proteins namely putative p23 co-chaperone, Thioredoxin h- rice, Ribulose-bisphosphate carboxylase large chain precursor, Nucleotide diPhosphate kinase, Proteosome sub unit protein and putative glutathione S-transferase protein. Conclusion Functional analyses of the differential proteins were reported to be directly or indirectly involved in growth promotion in plants. Thus, this study confirms the primary role of PGPR strain KH-1 in rice plant growth promotion.

Ihh/Gli2 signaling promotes osteoblast differentiation by regulating Runx2 expression and function.

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Shimoyama, Atsuko; Wada, Masahiro; Ikeda, Fumiyo; Hata, Kenji; Matsubara, Takuma; Nifuji, Akira; Noda, Masaki; Amano, Katsuhiko; Yamaguchi, Akira; Nishimura, Riko; Yoneda, Toshiyuki

2007-07-01

Genetic and cell biological studies have indicated that Indian hedgehog (Ihh) plays an important role in bone development and osteoblast differentiation. However, the molecular mechanism by which Ihh regulates osteoblast differentiation is complex and remains to be fully elucidated. In this study, we investigated the role of Ihh signaling in osteoblast differentiation using mesenchymal cells and primary osteoblasts. We observed that Ihh stimulated alkaline phosphatase (ALP) activity, osteocalcin expression, and calcification. Overexpression of Gli2- but not Gli3-induced ALP, osteocalcin expression, and calcification of these cells. In contrast, dominant-negative Gli2 markedly inhibited Ihh-dependent osteoblast differentiation. Ihh treatment or Gli2 overexpression also up-regulated the expression of Runx2, an essential transcription factor for osteoblastogenesis, and enhanced the transcriptional activity and osteogenic action of Runx2. Coimmunoprecipitation analysis demonstrated a physical interaction between Gli2 and Runx2. Moreover, Ihh or Gli2 overexpression failed to increase ALP activity in Runx2-deficient mesenchymal cells. Collectively, these results suggest that Ihh regulates osteoblast differentiation of mesenchymal cells through up-regulation of the expression and function of Runx2 by Gli2.

Amino-termini isoforms of the Slack K+ channel, regulated by alternative promoters, differentially modulate rhythmic firing and adaptation.

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Brown, Maile R; Kronengold, Jack; Gazula, Valeswara-Rao; Spilianakis, Charalampos G; Flavell, Richard A; von Hehn, Christian A A; Bhattacharjee, Arin; Kaczmarek, Leonard K

2008-11-01

these locations. Our data suggest that alternative promoters of the Slack gene differentially modulate the properties of neurones.

Repression of COUP-TFI Improves Bone Marrow-Derived Mesenchymal Stem Cell Differentiation into Insulin-Producing Cells

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Tao Zhang

2017-09-01

Full Text Available Identifying molecular mechanisms that regulate insulin expression in bone marrow-derived mesenchymal stem cells (bmMSCs can provide clues on how to stimulate the differentiation of bmMSCs into insulin-producing cells (IPCs, which can be used as a therapeutic approach against type 1 diabetes (T1D. As repression factors may inhibit differentiation, the efficiency of this process is insufficient for cell transplantation. In this study, we used the mouse insulin 2 (Ins2 promoter sequence and performed a DNA affinity precipitation assay combined with liquid chromatography-mass spectrometry to identify the transcription factor, chicken ovalbumin upstream promoter transcriptional factor I (COUP-TFI. Functionally, bmMSCs were reprogrammed into IPCs via COUP-TFI suppression and MafA overexpression. The differentiated cells expressed higher levels of genes specific for islet endocrine cells, and they released C-peptide and insulin in response to glucose stimulation. Transplantation of IPCs into streptozotocin-induced diabetic mice caused a reduction in hyperglycemia. Mechanistically, COUP-TFI bound to the DR1 (direct repeats with 1 spacer element in the Ins2 promoter, thereby negatively regulating promoter activity. Taken together, the data provide a novel mechanism by which COUP-TFI acts as a negative regulator in the Ins2 promoter. The differentiation of bmMSCs into IPCs could be improved by knockdown of COUP-TFI, which may provide a novel stem cell-based therapy for T1D. Keywords: siRNAs, differentiation, stem cell transplantation, diabetes, mesenchymal stem cells

Bioactive treatment promotes osteoblast differentiation on titanium materials fabricated by selective laser melting technology.

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Tsukanaka, Masako; Fujibayashi, Shunsuke; Takemoto, Mitsuru; Matsushita, Tomiharu; Kokubo, Tadashi; Nakamura, Takashi; Sasaki, Kiyoyuki; Matsuda, Shuichi

2016-01-01

Selective laser melting (SLM) technology is useful for the fabrication of porous titanium implants with complex shapes and structures. The materials fabricated by SLM characteristically have a very rough surface (average surface roughness, Ra=24.58 µm). In this study, we evaluated morphologically and biochemically the specific effects of this very rough surface and the additional effects of a bioactive treatment on osteoblast proliferation and differentiation. Flat-rolled titanium materials (Ra=1.02 µm) were used as the controls. On the treated materials fabricated by SLM, we observed enhanced osteoblast differentiation compared with the flat-rolled materials and the untreated materials fabricated by SLM. No significant differences were observed between the flat-rolled materials and the untreated materials fabricated by SLM in their effects on osteoblast differentiation. We concluded that the very rough surface fabricated by SLM had to undergo a bioactive treatment to obtain a positive effect on osteoblast differentiation.

Proportion of collagen type II in the extracellular matrix promotes the differentiation of human adipose-derived mesenchymal stem cells into nucleus pulposus cells.

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Tao, Yiqing; Zhou, Xiaopeng; Liu, Dongyu; Li, Hao; Liang, Chengzhen; Li, Fangcai; Chen, Qixin

2016-01-01

During degeneration process, the catabolism of collagen type II and anabolism of collagen type I in nucleus pulposus (NP) may influence the bioactivity of transplanted cells. Human adipose-derived mesenchymal stem cells (hADMSCs) were cultured as a micromass or in a series of gradual proportion hydrogels of a mix of collagen types I and II. Cell proliferation and cytotoxicity were detected using CCK-8 and LDH assays respectively. The expression of differentiation-related genes and proteins, including SOX9, aggrecan, collagen type I, and collagen type II, was examined using RT-qPCR and Western blotting. Novel phenotypic genes were also detected by RT-qPCR and western blotting. Alcian blue and dimethylmethylene blue assays were used to investigate sulfate proteoglycan expression, and PI3K/AKT, MAPK/ERK, and Smad signaling pathways were examined by Western blotting. The results showed collagen hydrogels have good biocompatibility, and cell proliferation increased after collagen type II treatment. Expressions of SOX9, aggrecan, and collagen type II were increased in a collagen type II dependent manner. Sulfate proteoglycan synthesis increased in proportion to collagen type II concentration. Only hADMSCs highly expressed NP cell marker KRT19 in collagen type II culture. Additionally, phosphorylated Smad3, which is associated with phosphorylated ERK, was increased after collagen type II-stimulation. The concentration and type of collagen affect hADMSC differentiation into NP cells. Collagen type II significantly ameliorates hADMSC differentiation into NP cells and promotes extracellular matrix synthesis. Therefore, anabolism of collagen type I and catabolism of type II may attenuate the differentiation and biosynthesis of transplanted stem cells. © 2016 International Union of Biochemistry and Molecular Biology.

Extrinsic factors promoting insulin producing cell-differentiation and insulin expression enhancement-hope for diabetics.

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Dave, Shruti

2013-11-01

Diabetes mellitus (DM) is considered to be an autoimmune disorder leading to destruction of beta-cells resulting in to a loss of blood sugar control. Attempts using many pharmacological compositions including exogenous insulin have failed to show tight control of glycemia and associated manifestations. Stem cells are considered a potential tool for the supply of insulin-producing cells (IPC) generation in vitro. Stem cell differentiation in to pancreatic lineages requires influence of both intrinsic and extrinsic factors. Application of islet growth factors is considered to be potential for enhancement of beta-cell replication, function and survival. Use of certain extrinsic factors is known to facilitate expression of transcription factors known to be important for beta-cell differentiation and production of insulin enabling IPC generation. Hierarchies of secreted signals and transcription factors have been identified by studies from several laboratories that guide cell differentiation in to IPC. This knowledge provides insights for in vitro IPC differentiation from stem cells. Current advancement in medical knowledge promises an insulin independency for DM patients. The review sheds light on few specific extrinsic factors which facilitate differentiation of stem cells in to IPC in vitro have been discussed; which can be proven as a potential therapeutic option for treatment of DM and associated diseases.

2-(trimethylammonium)ethyl (R)-3-methoxy-3-oxo-2-stearamidopropyl phosphate promotes megakaryocytic differentiation of myeloid leukaemia cells and primary human CD34⁺ haematopoietic stem cells.

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Limb, Jin-Kyung; Song, Doona; Jeon, Mijeong; Han, So-Yeop; Han, Gyoonhee; Jhon, Gil-Ja; Bae, Yun Soo; Kim, Jaesang

2015-04-01

In this study we showed that 2-(trimethylammonium)ethyl (R)-3-methoxy-3-oxo-2-stearamidopropyl phosphate [(R)-TEMOSPho], a derivative of an organic chemical identified from a natural product library, promotes highly efficient differentiation of megakaryocytes. Specifically, (R)-TEMOSPho induces cell cycle arrest, cell size increase and polyploidization from K562 and HEL cells, which are used extensively to model megakaryocytic differentiation. In addition, megakaryocyte-specific cell surface markers showed a dramatic increase in expression in response to (R)-TEMOSPho treatment. Importantly, we demonstrated that such megakaryocytic differentiation can also be induced from primary human CD34(+) haematopoietic stem cells. Activation of the PI3K-AKT pathway and, to a lesser extent, the MEK-ERK pathway appears to be required for this process, as blocking with specific inhibitors interferes with the differentiation of K562 cells. A subset of (R)-TEMOSPho-treated K562 cells undergoes spontaneous apoptosis and produces platelets that are apparently functional, as they bind to fibrinogen, express P-selectin and aggregate in response to SFLLRN and AYPGFK, the activating peptides for the PAR1 and PAR4 receptors, respectively. Taken together, these results indicate that (R)-TEMOSPho will be useful for dissecting the molecular mechanisms of megakaryocytic differentiation, and that this class of compounds represents potential therapeutic reagents for thrombocytopenia. Copyright © 2012 John Wiley & Sons, Ltd.

Ferritin nanoparticles for improved self-renewal and differentiation of human neural stem cells.

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Lee, Jung Seung; Yang, Kisuk; Cho, Ann-Na; Cho, Seung-Woo

2018-01-01

Biomaterials that promote the self-renewal ability and differentiation capacity of neural stem cells (NSCs) are desirable for improving stem cell therapy to treat neurodegenerative diseases. Incorporation of micro- and nanoparticles into stem cell culture has gained great attention for the control of stem cell behaviors, including proliferation and differentiation. In this study, ferritin, an iron-containing natural protein nanoparticle, was applied as a biomaterial to improve the self-renewal and differentiation of NSCs and neural progenitor cells (NPCs). Ferritin nanoparticles were added to NSC or NPC culture during cell growth, allowing for incorporation of ferritin nanoparticles during neurosphere formation. Compared to neurospheres without ferritin treatment, neurospheres with ferritin nanoparticles showed significantly promoted self-renewal and cell-cell interactions. When spontaneous differentiation of neurospheres was induced during culture without mitogenic factors, neuronal differentiation was enhanced in the ferritin-treated neurospheres. In conclusion, we found that natural nanoparticles can be used to improve the self-renewal ability and differentiation potential of NSCs and NPCs, which can be applied in neural tissue engineering and cell therapy for neurodegenerative diseases.

Selective AR Modulators that Distinguish Proliferative from Differentiative Gene Promoters

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2017-08-01

Public Release; Distribution Unlimited The views, opinions and/or findings contained in this report are those of the author(s) and should not be...Research and Materiel Command Fort Detrick, Maryland 21702-5012 11. SPONSOR/MONITOR’S REPORT NUMBER(S) 12. DISTRIBUTION / AVAILABILITY STATEMENT...recognition, we performed a high -throughput screen for compounds eliciting differential AR activity on cARE vs. sARE reporters. Of 10,000 compounds

International conference on differential and difference equations with applications

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Caraballo, Tomás; Kloeden, Peter; Graef, John

2018-01-01

This book gathers papers from the International Conference on Differential & Difference Equations and Applications 2017 (ICDDEA 2017), held in Lisbon, Portugal on June 5-9, 2017. The editors have compiled the strongest research presented at the conference, providing readers with valuable insights into new trends in the field, as well as applications and high-level survey results. The goal of the ICDDEA was to promote fruitful collaborations between researchers in the fields of differential and difference equations. All areas of differential and difference equations are represented, with a special emphasis on applications.

RAGE, receptor of advanced glycation endoproducts, negatively regulates chondrocytes differentiation.

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Tatsuya Kosaka

Full Text Available RAGE, receptor for advanced glycation endoproducts (AGE, has been characterized as an activator of osteoclastgenesis. However, whether RAGE directly regulates chondrocyte proliferation and differentiation is unclear. Here, we show that RAGE has an inhibitory role in chondrocyte differentiation. RAGE expression was observed in chondrocytes from the prehypertrophic to hypertrophic regions. In cultured cells, overexpression of RAGE or dominant-negative-RAGE (DN-RAGE demonstrated that RAGE inhibited cartilaginous matrix production, while DN-RAGE promoted production. Additionally, RAGE regulated Ihh and Col10a1 negatively but upregulated PTHrP receptor. Ihh promoter analysis and real-time PCR analysis suggested that downregulation of Cdxs was the key for RAGE-induced inhibition of chondrocyte differentiation. Overexpression of the NF-κB inhibitor I-κB-SR inhibited RAGE-induced NF-κB activation, but did not influence inhibition of cartilaginous matrix production by RAGE. The inhibitory action of RAGE was restored by the Rho family GTPases inhibitor Toxin B. Furthermore, inhibitory action on Ihh, Col10a1 and Cdxs was reproduced by constitutively active forms, L63RhoA, L61Rac, and L61Cdc42, but not by I-κB-SR. Cdx1 induced Ihh and Col10a1 expressions and directly interacted with Ihh promoter. Retinoic acid (RA partially rescued the inhibitory action of RAGE. These data combined suggests that RAGE negatively regulates chondrocyte differentiation at the prehypertrophic stage by modulating NF-κB-independent and Rho family GTPases-dependent mechanisms.

Three-dimensional spheroid culture promotes odonto/osteoblastic differentiation of dental pulp cells.

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Yamamoto, Mioko; Kawashima, Nobuyuki; Takashino, Nami; Koizumi, Yu; Takimoto, Koyo; Suzuki, Noriyuki; Saito, Masahiro; Suda, Hideaki

2014-03-01

Three-dimensional (3D) spheroid culture is a method for creating 3D aggregations of cells and their extracellular matrix without a scaffold mimicking the actual tissues. The aim of this study was to evaluate the effects of 3D spheroid culture on the phenotype of immortalized mouse dental papilla cells (MDPs) that have the ability to differentiate into odontoblasts. We cultured MDPs for 1, 3, 7, and 14 days in 96-well low-attachment culture plates for 3D spheroid culture or flat-bottomed plates for two-dimensional (2D) monolayer culture. Cell proliferation and apoptosis were detected by immunohistochemical staining of Ki67 and cleaved caspase-3, respectively. Hypoxia was measured by the hypoxia probe LOX-1. Odonto/osteoblastic differentiation marker gene expression was evaluated by quantitative PCR. We also determined mineralized nodule formation, alkaline phosphatase (ALP) activity, and dentine matrix protein-1 (DMP1) expression. Vinculin and integrin signalling-related proteins were detected immunohistochemically. Odonto/osteoblastic marker gene expression and mineralized nodule formation were significantly up-regulated in 3D spheroid-cultured MDPs compared with those in 2D monolayer-cultured MDPs (podonto/osteoblastic differentiation of MDPs, which may be mediated by integrin signalling. Copyright © 2013 Elsevier Ltd. All rights reserved.

Sparse dynamics for partial differential equations.

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Schaeffer, Hayden; Caflisch, Russel; Hauck, Cory D; Osher, Stanley

2013-04-23

We investigate the approximate dynamics of several differential equations when the solutions are restricted to a sparse subset of a given basis. The restriction is enforced at every time step by simply applying soft thresholding to the coefficients of the basis approximation. By reducing or compressing the information needed to represent the solution at every step, only the essential dynamics are represented. In many cases, there are natural bases derived from the differential equations, which promote sparsity. We find that our method successfully reduces the dynamics of convection equations, diffusion equations, weak shocks, and vorticity equations with high-frequency source terms.

Potential of Resveratrol Analogues as Antagonists of Osteoclasts and Promoters of Osteoblasts

DEFF Research Database (Denmark)

Kupisiewicz, Katarzyna; Boissy, Patrice; Abdallah, Basem M

2010-01-01

The plant phytoalexin resveratrol was previously demonstrated to inhibit the differentiation and bone resorbing activity of osteoclasts, to promote the formation of osteoblasts from mesenchymal precursors in cultures, and inhibit myeloma cell proliferation, when used at high concentrations....... In the current study, we screened five structurally modified resveratrol analogues for their ability to modify the differentiation of osteoclasts and osteoblasts and proliferation of myeloma cells. Compared to resveratrol, analogues showed an up to 5,000-fold increased potency to inhibit osteoclast...... differentiation. To a lesser extent, resveratrol analogues also promoted osteoblast maturation. However, they did not antagonize the proliferation of myeloma cells. The potency of the best-performing candidate in vitro was tested in vivo in an ovariectomy-induced model of osteoporosis, but an effect on bone loss...

Direct and indirect effects in the regulation of overlapping promoters

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Bendtsen, Kristian Moss; Erdossy, Janos; Csiszovski, Zsolt

2011-01-01

promoter database we found that ~14% of the identified 'forward' promoters overlap with a promoter oriented in the opposite direction. In this article we combine a mathematical model with experimental analysis of synthetic regulatory regions to investigate interference of overlapping promoters. We find...... that promoter interference depends on the characteristics of overlapping promoters. The model predicts that promoter strength and interference can be regulated separately, which provides unique opportunities for regulation. Our experimental data suggest that in principle any DNA binding protein can be used......Optimal response to environmental stimuli often requires activation of certain genes and repression of others. Dual function regulatory proteins play a key role in the differential regulation of gene expression. While repression can be achieved by any DNA binding protein through steric occlusion...

Overexpression of miR‑21 promotes neural stem cell proliferation and neural differentiation via the Wnt/β‑catenin signaling pathway in vitro.

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Zhang, Wei-Min; Zhang, Zhi-Ren; Yang, Xi-Tao; Zhang, Yong-Gang; Gao, Yan-Sheng

2018-01-01

The primary aim of the present study was to examine the effects of microRNA‑21 (miR‑21) on the proliferation and differentiation of rat primary neural stem cells (NSCs) in vitro. miR‑21 was overexpressed in NSCs by transfection with a miR‑21 mimic. The effects of miR‑21 overexpression on NSC proliferation were revealed by Cell Counting kit 8 and 5‑ethynyl‑2'‑deoxyuridine incorporation assay, and miR‑21 overexpression was revealed to increase NSC proliferation. miR‑21 overexpression was confirmed using reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR). mRNA and protein expression levels of key molecules (β‑catenin, cyclin D1, p21 and miR‑21) in the Wnt/β‑catenin signaling pathway were studied by RT‑qPCR and western blot analysis. RT‑qPCR and western blot analyses revealed that miR‑21 overexpression increased β‑catenin and cyclin D1 expression, and decreased p21 expression. These results suggested that miR‑21‑induced increase in proliferation was mediated by activation of the Wnt/β‑catenin signaling pathway, since overexpression of miR‑21 increased β‑catenin and cyclin D1 expression and reduced p21 expression. Furthermore, inhibition of the Wnt/β‑catenin pathway with FH535 attenuated the influence of miR‑21 overexpression on NSC proliferation, indicating that the factors activated by miR‑21 overexpression were inhibited by FH535 treatment. Furthermore, overexpression of miR‑21 enhanced the differentiation of NSCs into neurons and inhibited their differentiation into astrocytes. The present study indicated that in primary rat NSCs, overexpression of miR‑21 may promote proliferation and differentiation into neurons via the Wnt/β‑catenin signaling pathway in vitro.

Identification and characterization of the human SOX6 promoter

International Nuclear Information System (INIS)

Ikeda, Toshiyuki; Saito, Taku; Ushita, Masahiro; Yano, Fumiko; Kan, Akinori; Itaka, Keiji; Moro, Toru; Nakamura, Kozo; Kawaguchi, Hiroshi; Chung, Ung-il

2007-01-01

The present study attempted to identify and characterize the embryonic promoter of Sox6, a determinant regulator of chondrogenic differentiation. A common transcription start region for human and mouse Sox6 was initially identified, which contained a highly conserved sequence, A-box. Tandem repeats of A-box had a strong transcriptional activity both at the basal level and in response to Sox9. Cells carrying the 4xA-box-DsRed2 reporter fluoresced only upon chondrogenic differentiation. The 46-bp core enhancer region (CES6) was then identified in the 3' half of A-box, within which a C/EBP-binding motif was identified. Overexpressed C/EBPβ activated the Sox6 promoter, and mutant 4xCES6 constructs lacking the C/EBP motif lost their basal activity. CES6 and nuclear extracts formed a specific complex, which was supershifted by anti-C/EBPβ antibody, and in vitro translated C/EBPβ specifically bound to CES6. Thus, we successfully identified the Sox6 promoter and its core enhancer and characterized the interactions with regulatory transcription factors

JAZF1 promotes proliferation of C2C12 cells, but retards their myogenic differentiation through transcriptional repression of MEF2C and MRF4—Implications for the role of Jazf1 variants in oncogenesis and type 2 diabetes

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Yuasa, Katsutoshi; Aoki, Natsumi; Hijikata, Takao, E-mail: hijikata@musashino-u.ac.jp

2015-08-15

Single-nucleotide polymorphisms associated with type 2 diabetes (T2D) have been identified in Jazf1, which is also involved in the oncogenesis of endometrial stromal tumors. To understand how Jazf1 variants confer a risk of tumorigenesis and T2D, we explored the functional roles of JAZF1 and searched for JAZF1 target genes in myogenic C2C12 cells. Consistent with an increase of Jazf1 transcripts during myoblast proliferation and their decrease during myogenic differentiation in regenerating skeletal muscle, JAZF1 overexpression promoted cell proliferation, whereas it retarded myogenic differentiation. Examination of myogenic genes revealed that JAZF1 overexpression transcriptionally repressed MEF2C and MRF4 and their downstream genes. AMP deaminase1 (AMPD1) was identified as a candidate for JAZF1 target by gene array analysis. However, promoter assays of Ampd1 demonstrated that mutation of the putative binding site for the TR4/JAZF1 complex did not alleviate the repressive effects of JAZF1 on promoter activity. Instead, JAZF1-mediated repression of Ampd1 occurred through the MEF2-binding site and E-box within the Ampd1 proximal regulatory elements. Consistently, MEF2C and MRF4 expression enhanced Ampd1 promoter activity. AMPD1 overexpression and JAZF1 downregulation impaired AMPK phosphorylation, while JAZF1 overexpression also reduced it. Collectively, these results suggest that aberrant JAZF1 expression contributes to the oncogenesis and T2D pathogenesis. - Highlights: • JAZF1 promotes cell cycle progression and proliferation of myoblasts. • JAZF1 retards myogenic differentiation and hypertrophy of myotubes. • JAZF1 transcriptionally represses Mef2C and Mrf4 expression. • JAZF1 has an impact on the phosphorylation of AMPK.

Factors promoting tourism services and their development

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Simona Cristina Martin

2013-10-01

Because the fact that tourism services are intangible, sales through self-service are impossible, which makes indispensable the presence of the seller or counselor at the point of sale. Unable to clearly differentiate against competitors, tourist trips wholesalers will practice a more limited range of methods of sales promotion.

Fasting exacerbates hepatic growth differentiation factor 15 to promote fatty acid β-oxidation and ketogenesis via activating XBP1 signaling in liver

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Meiyuan Zhang

2018-06-01

Full Text Available Liver coordinates a series of metabolic adaptations to maintain systemic energy balance and provide adequate nutrients for critical organs, tissues and cells during starvation. However, the mediator(s implicated in orchestrating these fasting-induced adaptive responses and the underlying molecular mechanisms are still obscure. Here we show that hepatic growth differentiation factor 15 (GDF15 is regulated by IRE1α-XBP1s branch and promotes hepatic fatty acids β-oxidation and ketogenesis upon fasting. GDF15 expression was exacerbated in liver of mice subjected to long-term fasted or ketogenic diet feeding. Abrogation of hepatic Gdf15 dramatically attenuated hepatic β-oxidation and ketogenesis in fasted mice or mice with STZ-initiated type I diabetes. Further study revealed that XBP1s activated Gdf15 transcription via binding to its promoter. Elevated GDF15 in liver reduced lipid accumulation and impaired NALFD development in obese mice through enhancing fatty acids oxidation in liver. Therefore, our results demonstrate a novel and critical role of hepatic GDF15 activated by IRE1α-XBP1s branch in regulating adaptive responses of liver upon starvation stress. Keywords: Fasting, Fatty acid β-oxidation, Ketogenesis, GDF15, XBP1, NAFLD

Ordinary differential equations

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Cox, William

1995-01-01

Building on introductory calculus courses, this text provides a sound foundation in the underlying principles of ordinary differential equations. Important concepts, including uniqueness and existence theorems, are worked through in detail and the student is encouraged to develop much of the routine material themselves, thus helping to ensure a solid understanding of the fundamentals required.The wide use of exercises, problems and self-assessment questions helps to promote a deeper understanding of the material and it is developed in such a way that it lays the groundwork for further

Ti nanorod arrays with a medium density significantly promote osteogenesis and osteointegration

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Ning, Chengyun; Wang, Shuangying; Zhu, Ye; Zhong, Meiling; Lin, Xi; Zhang, Yu; Tan, Guoxin; Li, Mei; Yin, Zhaoyi; Yu, Peng; Wang, Xiaolan; Li, Ying; He, Tianrui; Chen, Wei; Wang, Yingjun; Mao, Chuanbin

2016-01-01

Ti implants are good candidates in bone repair. However, how to promote bone formation on their surface and their consequent perfect integration with the surrounding tissue is still a challenge. To overcome such challenge, we propose to form Ti nanorods on their surface to promote the new bone formation around the implants. Here Ti nanorod arrays (TNrs) with different densities were produced on pure Ti surfaces using an anodizing method. The influence of TNr density on the protein adsorption as well as on the adhesion, proliferation, and osteogenic differentiation of MC3T3-E1 pre-osteoblastic cells were assessed. The TNrs were also implanted into the bone defects in rabbits to test their application in promoting bone formation and osteointegration at the implant-bone interface. TNrs with the medium density were found to show the best capability in promoting the protein adsorption from surrounding medium, which in turn efficiently enhanced osteogenic differentiation in vitro and osteointegration in vivo. Our work suggests that growing TNrs with a medium density on the surface of traditional Ti implants is an efficient and facile method for promoting bone formation and osteointegration in bone repair.

Potassium recycling pathways in the human cochlea.

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Weber, P C; Cunningham, C D; Schulte, B A

2001-07-01

Potential pathways for recycling potassium (K+) used in the maintenance of inner ear electrochemical gradients have been elucidated in animal models. However, little is known about K+ transport in the human cochlea. This study was designed to characterize putative K+ recycling pathways in the human ear and to determine whether observations from animal models can be extrapolated to humans. A prospective laboratory study using an immunohistochemical approach to analyze the distribution of key ion transport mediators in the human cochlea. Human temporal bones were fixed in situ within 1 to 6 hours of death and subsequently harvested at autopsy. Decalcification was accomplished with the aid of microwaving. Immunohistochemical staining was then performed to define the presence and cell type-specific distribution of Na,K-ATPase, sodium-potassium-chloride cotransporter (NKCC), and carbonic anhydrase (CA) in the inner ear. Staining patterns visualized in the human cochlea closely paralleled those seen in other species. Anti-Na,K-ATPase stained strongly the basolateral plasma membrane of strial marginal cells and nerve endings underlying hair cells. This antibody also localized Na,K-ATPase to type II, type IV, and type V fibrocytes in the spiral ligament and in limbal fibrocytes. NKCC was present in the basolateral membrane of strial marginal cells as well as in type II, type V, and limbal fibrocytes. Immunoreactive carbonic anhydrase was present in type I and type III fibrocytes and in epithelial cells lining Reissner's membrane and the spiral prominence. The distribution of several major ion transport proteins in the human cochlea is similar but not identical to that described in various rodent models. These results support the presence of a complex system for recycling and regulating K+ homeostasis in the human cochlea, similar to that described in other mammalian species.

Mineral trioxide aggregate promotes the odonto/osteogenic differentiation and dentinogenesis of stem cells from apical papilla via nuclear factor kappa B signaling pathway.

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Yan, Ming; Wu, Jintao; Yu, Yan; Wang, Yanping; Xie, Lizhe; Zhang, Guangdong; Yu, Jinhua; Zhang, Chengfei

2014-05-01

Mineral trioxide aggregate (MTA) has been widely used in clinical apexification and apexogenesis. However, the effects of MTA on the stem cells from apical papilla (SCAPs) and the precise mechanism of apexogenesis have not been elucidated in detail. Multiple colony-derived stem cells were isolated from the apical papillae, and the effects of MTA on the proliferation and differentiation of SCAPs were investigated both in vitro and in vivo. Activation of nuclear factor kappa B (NFκB) pathway in MTA-treated SCAPs was analyzed by immunofluorescence assay and Western blot. MTA at the concentration of 2 mg/mL did not affect the proliferation activity of SCAPs. However, 2 mg/mL MTA-treated SCAPs presented the ultrastructural changes, up-regulated alkaline phosphatase, increased calcium deposition, up-regulated expression of odontoblast markers (dentin sialoprotein and dentin sialophosphoprotein) and odonto/osteoblast markers (runt-related transcription factor 2 and osteocalcin), suggesting that MTA enhanced the odonto/osteoblastic differentiation of SCAPs in vitro. In vivo results confirmed that MTA can promote the regular dentinogenesis of SCAPs. Moreover, MTA-treated SCAPs exhibited the up-regulated cytoplasmic phos-IκBα and phos-P65, enhanced nuclear P65, and increased nuclear translocation of P65. When co-treated with BMS345541 (the specific NFκB inhibitor), MTA-mediated odonto/osteoblastic differentiation was significantly attenuated. MTA at the concentration of 2 mg/mL can improve the odonto/osteogenic capacity of SCAPs via the activation of NFκB pathway. Copyright © 2014 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

MyT1 Counteracts the Neural Progenitor Program to Promote Vertebrate Neurogenesis

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Francisca F. Vasconcelos

2016-10-01

Full Text Available The generation of neurons from neural stem cells requires large-scale changes in gene expression that are controlled to a large extent by proneural transcription factors, such as Ascl1. While recent studies have characterized the differentiation genes activated by proneural factors, less is known on the mechanisms that suppress progenitor cell identity. Here, we show that Ascl1 induces the transcription factor MyT1 while promoting neuronal differentiation. We combined functional studies of MyT1 during neurogenesis with the characterization of its transcriptional program. MyT1 binding is associated with repression of gene transcription in neural progenitor cells. It promotes neuronal differentiation by counteracting the inhibitory activity of Notch signaling at multiple levels, targeting the Notch1 receptor and many of its downstream targets. These include regulators of the neural progenitor program, such as Hes1, Sox2, Id3, and Olig1. Thus, Ascl1 suppresses Notch signaling cell-autonomously via MyT1, coupling neuronal differentiation with repression of the progenitor fate.

Heterogeneity in Fibroblast Proliferation and Survival in Idiopathic Pulmonary Fibrosis

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David Michael Habiel

2014-01-01

Full Text Available Idiopathic pulmonary fibrosis (IPF is the most common form of interstitial lung disease characterized by the persistence of activated myofibroblasts resulting in excessive deposition of extracellular matrix proteins and profound tissue remodeling. Myofibroblasts have been shown to arise from interstitial fibroblasts, epithelial to mesenchymal transition of type II alveolar epithelial cells, and the differentiation of recruited fibrocytes. There are many mechanisms that are utilized by these cells for survival, proliferation and persistent activation including up-regulation of cytokines (i.e. Interlukin 6 (IL-6, cytokine receptors (i.e. Interlukin 6 Receptor 1 (IL-6R1, Glycoprotein 130 (gp130 and C-C Chemokine Receptor type 7 (CCR7 and innate pattern recognition receptors (PRRs; i.e. Toll Like Receptor 9 (TLR9. In this review, we will discuss the role of the cytokines IL-6 and CCL21, their receptors and the pattern recognition receptor (PRR, TLR9, in fibroblast recruitment, activation, survival and differentiation into myofibroblasts in IPF.

Role of hormones in controlling vascular differentiation and the mechanism of lateral root initiation.

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Aloni, Roni

2013-11-01

The vascular system in plants is induced and controlled by streams of inductive hormonal signals. Auxin produced in young leaves is the primary controlling signal in vascular differentiation. Its polar and non-polar transport pathways and major controlling mechanisms are clarified. Ethylene produced in differentiating protoxylem vessels is the signal that triggers lateral root initiation, while tumor-induced ethylene is a limiting and controlling factor of crown gall development and its vascular differentiation. Gibberellin produced in mature leaves moves non-polarly and promotes elongation, regulates cambium activity and induces long fibers. Cytokinin from the root cap moves upward to promote cambial activity and stimulate shoot growth and branching, while strigolactone from the root inhibits branching. Furthermore, the role of the hormonal signals in controlling the type of differentiating vascular elements and gradients of conduit size and density, and how they regulate plant adaptation and have shaped wood evolution are elucidated.

Genome-wide Anaplasma phagocytophilum AnkA-DNA interactions are enriched in intergenic regions and gene promoters and correlate with infection-induced differential gene expression.

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J Stephen Dumler

2016-09-01

Full Text Available Anaplasma phagocytophilum, an obligate intracellular prokaryote, infects neutrophils and alters cardinal functions via reprogrammed transcription. Large contiguous regions of neutrophil chromosomes are differentially expressed during infection. Secreted A. phagocytophilum effector AnkA transits into the neutrophil or granulocyte nucleus to complex with DNA in heterochromatin across all chromosomes. AnkA binds to gene promoters to dampen cis-transcription and also has features of matrix attachment region (MAR-binding proteins that regulate three-dimensional chromatin architecture and coordinate transcriptional programs encoded in topologically-associated chromatin domains. We hypothesize that identification of additional AnkA binding sites will better delineate how A. phagocytophilum infection results in reprogramming of the neutrophil genome. Using AnkA-binding ChIP-seq, we showed that AnkA binds broadly throughout all chromosomes in a reproducible pattern, especially at: i intergenic regions predicted to be matrix attachment regions (MARs; ii within predicted lamina-associated domains; and iii at promoters ≤3,000 bp upstream of transcriptional start sites. These findings provide genome-wide support for AnkA as a regulator of cis-gene transcription. Moreover, the dominant mark of AnkA in distal intergenic regions known to be AT-enriched, coupled with frequent enrichment in the nuclear lamina, provides strong support for its role as a MAR-binding protein and genome re-organizer. AnkA must be considered a prime candidate to promote neutrophil reprogramming and subsequent functional changes that belie improved microbial fitness and pathogenicity.

RANK ligand signaling modulates the matrix metalloproteinase-9 gene expression during osteoclast differentiation

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Sundaram, Kumaran; Nishimura, Riko; Senn, Joseph; Youssef, Rimon F.; London, Steven D.; Reddy, Sakamuri V.

2007-01-01

Osteoclast differentiation is tightly regulated by receptor activator of NF-κB ligand (RANKL) signaling. Matrix metalloproteinase-9 (MMP-9), a type IV collagenase is highly expressed in osteoclast cells and plays an important role in degradation of extracellular matrix; however, the molecular mechanisms that regulate MMP-9 gene expression are unknown. In this study, we demonstrate that RANKL signaling induces MMP-9 gene expression in osteoclast precursor cells. We further show that RANKL regulates MMP-9 gene expression through TRAF6 but not TRAF2. Interestingly, blockade of p38 MAPK activity by pharmacological inhibitor, SB203580 increases MMP-9 activity whereas ERK1/2 inhibitor, PD98059 decreases RANKL induced MMP-9 activity in RAW264.7 cells. These data suggest that RANKL differentially regulates MMP-9 expression through p38 and ERK signaling pathways during osteoclast differentiation. Transient expression of MMP-9 gene (+ 1 to - 1174 bp relative to ATG start codon) promoter-luciferase reporter plasmids in RAW264.7 cells and RANKL stimulation showed significant increase (20-fold) of MMP-9 gene promoter activity; however, there is no significant change with respect to + 1 bp to - 446 bp promoter region and empty vector transfected cells. These results indicated that MMP-9 promoter sequence from - 446 bp to - 1174 bp relative to start codon is responsive to RANKL stimulation. Sequence analysis of the mouse MMP-9 gene promoter region further identified the presence of binding motif (- 1123 bp to - 1153 bp) for the nuclear factor of activated T cells 1 (NFATc1) transcription factor. Inhibition of NFATc1 using siRNA and VIVIT peptide inhibitor significantly decreased RANKL stimulation of MMP-9 activity. We further confirm by oligonucleotide pull-down assay that RANKL stimuli enhanced NFATc1 binding to MMP-9 gene promoter element. In addition, over-expression of constitutively active NFAT in RAW264.7 cells markedly increased (5-fold) MMP-9 gene promoter activity in

Effect of growth factors (BMP-4/7 & bFGF on proliferation & osteogenic differentiation of bone marrow stromal cells

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Shaohui Yuan

2013-01-01

Full Text Available Background & objectives: BMP (bone morphogenetic protein-4/7 and bFGF (basic fibroblast growth factor significantly promote the osteogenic activity and the proliferation of rabbit BMSCs (bone marrow stromal cells, respectively. However, their synergistic effects on the proliferation and the differentiation of BMSCs remain unclear. In the present study, the effects of bFGF and BMP-4/7 were investigated on the proliferation and the differentiation of rat BMSCs in vitro. Methods: BMSCs were isolated from New Zealand white rabbits and cultured to the third passage. The samples were divided into five groups according to the material implanted: (A 80 ng/ml BMP-4/7; (B 80 ng/ml bFGF; (C 30 ng/ml BMP-4/7 and 30 ng/ml bFGF; (D 50 ng/ml BMP-4/7 and 50 ng/ml bFGF; and (E 80 ng/ml BMP-4/7 and 80 ng/ml bFGF. Cell proliferation was analyzed using methyl thiazolyl tetrazolium (MTT assay. Alkaline phosphatase activity and osteocalcin (OC dynamics were also measured. Results: BMP-4/7 alone significantly (P<0.05 promoted the proliferation of BMSCs. At the same time, it also promoted or inhibited the osteogenic differentiation of BMSCs. The synergistic effects of BMP-4/7 and bFGF significantly promoted both the proliferation and the osteogenic differentiation of BMSCs. The treatment of the synergistic effects was dose and time dependent. Interpretation & conclusions: A rational combination of BMP-4/7 and bFGF can promote the proliferation and the osteogenic differentiation of BMSCs. In addition, the synergistic functions are effective.

Toll like Receptor 2 engagement on CD4+ T cells promotes TH9 differentiation and function.

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Karim, Ahmad Faisal; Reba, Scott M; Li, Qing; Boom, W Henry; Rojas, Roxana E

2017-09-01

We have recently demonstrated that mycobacterial ligands engage Toll like receptor 2 (TLR2) on CD4 + T cells and up-regulate T-cell receptor (TCR) triggered Th1 responses in vitro and in vivo. To better understand the role of T-cell expressed TLR2 on CD4 + T-cell differentiation and function, we conducted a gene expression analysis of murine naïve CD4 + T-cells stimulated in the presence or absence of TLR2 co-stimulation. Unexpectedly, naïve CD4 + T-cells co-stimulated via TLR2 showed a significant up-regulation of Il9 mRNA compared to cells co-stimulated via CD28. Under TH9 differentiation, we observed up-regulation of TH9 differentiation, evidenced by increases in both percent of IL-9 secreting cells and IL-9 in culture supernatants in the presence of TLR2 agonist both in polyclonal and Ag85B cognate peptide specific stimulations. Under non-polarizing conditions, TLR2 engagement on CD4 + T-cells had minimal effect on IL-9 secretion and TH9 differentiation, likely due to a prominent effect of TLR2 signaling on IFN-γ secretion and TH1 differentiation. We also report that, TLR2 signaling in CD4 + T cells increased expression of transcription factors BATF and PU.1, known to positively regulate TH9 differentiation. These results reveal a novel role of T-cell expressed TLR2 in enhancing the differentiation and function of TH9 T cells. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The endocrine disruptor diethylstilbestrol induces adipocyte differentiation and promotes obesity in mice

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Hao, Chan-Juan; Cheng, Xue-Jia; Xia, Hong-Fei, E-mail: hongfeixia@yahoo.com.cn; Ma, Xu

2012-08-15

Epidemiology studies indicate that exposure to endocrine disruptors during developmental “window” contributes to adipogenesis and the development of obesity. Implication of endocrine disruptor such as diethylstilbestrol (DES) on adipose tissue development has been poorly investigated. Here we evaluated the effects of DES on adipocyte differentiation in vitro and in vivo, and explored potential mechanism involved in its action. DES induced 3T3-L1 preadipocyte differentiation in a dose-dependent manner, and activated the expression of estrogen receptor (ER) and peroxisome proliferator-acivated receptor (PPAR) γ as well as its target genes required for adipogenesis in vitro. ER mediated the enhancement of DES-induced PPARγ activity. Moreover, DES perturbed key regulators of adipogenesis and lipogenic pathway in vivo. In utero exposure to low dose of DES significantly increased body weight, liver weight and fat mass in female offspring at postnatal day (PND) 60. In addition, serum triglyceride and glucose levels were also significantly elevated. These results suggest that perinatal exposure to DES may be expected to increase the incidence of obesity in a sex-dependent manner and can act as a potential chemical stressor for obesity and obesity-related disorders. -- Highlights: ► DES induced adipocyte differentiation in a dose-dependent manner in 3T3-L1 cells. ► DES activated adipogenic critical regulators and markers in vitro and in vivo. ► Perinatal exposure to DES led to the obese phenotype in female offspring. ► DES might be a potential chemical stressor for obesity and obesity-related disorders.

The endocrine disruptor diethylstilbestrol induces adipocyte differentiation and promotes obesity in mice

International Nuclear Information System (INIS)

Hao, Chan-Juan; Cheng, Xue-Jia; Xia, Hong-Fei; Ma, Xu

2012-01-01

Epidemiology studies indicate that exposure to endocrine disruptors during developmental “window” contributes to adipogenesis and the development of obesity. Implication of endocrine disruptor such as diethylstilbestrol (DES) on adipose tissue development has been poorly investigated. Here we evaluated the effects of DES on adipocyte differentiation in vitro and in vivo, and explored potential mechanism involved in its action. DES induced 3T3-L1 preadipocyte differentiation in a dose-dependent manner, and activated the expression of estrogen receptor (ER) and peroxisome proliferator-acivated receptor (PPAR) γ as well as its target genes required for adipogenesis in vitro. ER mediated the enhancement of DES-induced PPARγ activity. Moreover, DES perturbed key regulators of adipogenesis and lipogenic pathway in vivo. In utero exposure to low dose of DES significantly increased body weight, liver weight and fat mass in female offspring at postnatal day (PND) 60. In addition, serum triglyceride and glucose levels were also significantly elevated. These results suggest that perinatal exposure to DES may be expected to increase the incidence of obesity in a sex-dependent manner and can act as a potential chemical stressor for obesity and obesity-related disorders. -- Highlights: ► DES induced adipocyte differentiation in a dose-dependent manner in 3T3-L1 cells. ► DES activated adipogenic critical regulators and markers in vitro and in vivo. ► Perinatal exposure to DES led to the obese phenotype in female offspring. ► DES might be a potential chemical stressor for obesity and obesity-related disorders.

Rho-associated kinase inhibitors promote the cardiac differentiation of embryonic and induced pluripotent stem cells.

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Cheng, Ya-Ting; Yeih, Dong-Feng; Liang, Shu-Man; Chien, Chia-Ying; Yu, Yen-Ling; Ko, Bor-Sheng; Jan, Yee-Jee; Kuo, Cheng-Chin; Sung, Li-Ying; Shyue, Song-Kun; Chen, Ming-Fong; Yet, Shaw-Fang; Wu, Kenneth K; Liou, Jun-Yang

2015-12-15

Rho-associated kinase (ROCK) plays an important role in maintaining embryonic stem (ES) cell pluripotency. To determine whether ROCK is involved in ES cell differentiation into cardiac and hematopoietic lineages, we evaluated the effect of ROCK inhibitors, Y-27632 and fasudil on murine ES and induced pluripotent stem (iPS) cell differentiation. Gene expression levels were determined by real-time PCR, Western blot analysis and immunofluorescent confocal microscopy. Cell transplantation of induced differentiated cells were assessed in vivo in a mouse model (three groups, n=8/group) of acute myocardial infarction (MI). The cell engraftment was examined by immunohistochemical staining and the outcome was analyzed by echocardiography. Cells were cultured in hematopoietic differentiation medium in the presence or absence of ROCK inhibitor and colony formation as well as markers of ES, hematopoietic stem cells (HSC) and cells of cardiac lineages were analyzed. ROCK inhibition resulted in a drastic change in colony morphology accompanied by loss of hematopoietic markers (GATA-1, CD41 and β-Major) and expressed markers of cardiac lineages (GATA-4, Isl-1, Tbx-5, Tbx-20, MLC-2a, MLC-2v, α-MHC, cTnI and cTnT) in murine ES and iPS cells. Fasudil-induced cardiac progenitor (Mesp-1 expressing) cells were infused into a murine MI model. They engrafted into the peri-infarct and infarct regions and preserved left ventricular function. These findings provide new insights into the signaling required for ES cell differentiation into hematopoietic as well as cardiac lineages and suggest that ROCK inhibitors are useful in directing iPS cell differentiation into cardiac progenitor cells for cell therapy of cardiovascular diseases. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Alternative Splicing of G9a Regulates Neuronal Differentiation

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Ana Fiszbein

2016-03-01

Full Text Available Chromatin modifications are critical for the establishment and maintenance of differentiation programs. G9a, the enzyme responsible for histone H3 lysine 9 dimethylation in mammalian euchromatin, exists as two isoforms with differential inclusion of exon 10 (E10 through alternative splicing. We find that the G9a methyltransferase is required for differentiation of the mouse neuronal cell line N2a and that E10 inclusion increases during neuronal differentiation of cultured cells, as well as in the developing mouse brain. Although E10 inclusion greatly stimulates overall H3K9me2 levels, it does not affect G9a catalytic activity. Instead, E10 increases G9a nuclear localization. We show that the G9a E10+ isoform is necessary for neuron differentiation and regulates the alternative splicing pattern of its own pre-mRNA, enhancing E10 inclusion. Overall, our findings indicate that by regulating its own alternative splicing, G9a promotes neuron differentiation and creates a positive feedback loop that reinforces cellular commitment to differentiation.

Small-Molecule Induction Promotes Corneal Epithelial Cell Differentiation from Human Induced Pluripotent Stem Cells

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Alexandra Mikhailova

2014-02-01

Full Text Available Human induced pluripotent stem cells (hiPSCs offer unique opportunities for developing novel cell-based therapies and disease modeling. In this study, we developed a directed differentiation method for hiPSCs toward corneal epithelial progenitor cells capable of terminal differentiation toward mature corneal epithelial-like cells. In order to improve the efficiency and reproducibility of our method, we replicated signaling cues active during ocular surface ectoderm development with the help of two small-molecule inhibitors in combination with basic fibroblast growth factor (bFGF in serum-free and feeder-free conditions. First, small-molecule induction downregulated the expression of pluripotency markers while upregulating several transcription factors essential for normal eye development. Second, protein expression of the corneal epithelial progenitor marker p63 was greatly enhanced, with up to 95% of cells being p63 positive after 5 weeks of differentiation. Third, corneal epithelial-like cells were obtained upon further maturation.

LncRNA TUG1 sponges miR-204-5p to promote osteoblast differentiation through upregulating Runx2 in aortic valve calcification.

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Yu, Cong; Li, Lifu; Xie, Fei; Guo, Shichao; Liu, Fayuan; Dong, Nianguo; Wang, Yongjun

2018-01-01

Emerging evidence indicates that long non-coding RNAs (lncRNAs) play a vital role in cardiovascular physiology and pathology. Although the lncRNA TUG1 is implicated in atherosclerosis, its function in calcific aortic valve disease (CAVD) remains unknown. In this study, we found that TUG1 was highly expressed in human aortic valves and primary valve interstitial cells (VICs). Moreover, TUG1 knockdown induced inhibition of osteoblast differentiation in CAVD both in vitro and in vivo. Mechanistically, silencing of TUG1 increased the expression of miR-204-5p and subsequently inhibited Runx2 expression at the post-transcriptional level. Importantly, TUG1 directly interacted with miR-204-5p and downregulation of miR-204-5p efficiently reversed the suppression of Runx2 induced by TUG1 short hairpin RNA (shRNA). Thus, TUG1 positively regulated the expression of Runx2, through sponging miR-204-5p, and promoted osteogenic differentiation in CAVD. All together, the evidence generated by our study elucidates the role of lncRNA TUG1 as a miRNA sponge in CAVD, and sheds new light on lncRNA-directed diagnostics and therapeutics in CAVD. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2017. For permissions please email: journals.permissions@oup.com.

All-trans retinoic acid promotes neural lineage entry by pluripotent embryonic stem cells via multiple pathways

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Fang Bo

2009-07-01

Full Text Available Abstract Background All-trans retinoic acid (RA is one of the most important morphogens with pleiotropic actions. Its embryonic distribution correlates with neural differentiation in the developing central nervous system. To explore the precise effects of RA on neural differentiation of mouse embryonic stem cells (ESCs, we detected expression of RA nuclear receptors and RA-metabolizing enzymes in mouse ESCs and investigated the roles of RA in adherent monolayer culture. Results Upon addition of RA, cell differentiation was directed rapidly and exclusively into the neural lineage. Conversely, pharmacological interference with RA signaling suppressed this neural differentiation. Inhibition of fibroblast growth factor (FGF signaling did not suppress significantly neural differentiation in RA-treated cultures. Pharmacological interference with extracellular signal-regulated kinase (ERK pathway or activation of Wnt pathway effectively blocked the RA-promoted neural specification. ERK phosphorylation was enhanced in RA-treated cultures at the early stage of differentiation. Conclusion RA can promote neural lineage entry by ESCs in adherent monolayer culture systems. This effect depends on RA signaling and its crosstalk with the ERK and Wnt pathways.

Characterization of Chondrogenic Gene Expression and Cartilage Phenotype Differentiation in Human Breast Adipose-Derived Stem Cells Promoted by Ginsenoside Rg1 In Vitro

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Fang-Tian Xu

2015-11-01

Full Text Available Background/Aims: Investigating and understanding chondrogenic gene expression during the differentiation of human breast adipose-derived stem cells (HBASCs into chondrogenic cells is a prerequisite for the application of this approach for cartilage repair and regeneration. In this study, we aim to characterize HBASCs and to examine chondrogenic gene expression in chondrogenic inductive culture medium containing ginsenoside Rg1. Methods: Human breast adipose-derived stem cells at passage 3 were evaluated based on specific cell markers and their multilineage differentiation capacity. Cultured HBASCs were treated either with basic chondrogenic inductive conditioned medium alone (group A, control or with basic chondrogenic inductive medium plus 10 µg/ml (group B, 50 µg/ml (group C, or 100µg/ml ginsenoside Rg1 (group D. Cell proliferation was assessed using the CCK-8 assay for a period of 9 days. Two weeks after induction, the expression of chondrogenic genes (collagen type II, collagen type XI, ACP, COMP and ELASTIN was determined using real-time PCR in all groups. Results: The different concentrations of ginsenoside Rg1 that were added to the basic chondrogenic inductive culture medium promoted the proliferation of HBASCs at earlier stages (groups B, C, and D but resulted in chondrogenic phenotype differentiation and higher mRNA expression of collagen type II (CO-II, collagen type XI (CO-XI, acid phosphatase (ACP, cartilage oligomeric matrix protein (COMP and ELASTIN compared with the control (group A at later stages. The results reveal an obvious positive dose-effect relationship between ginsenoside Rg1 and the proliferation and chondrogenic phenotype differentiation of HBASCs in vitro. Conclusions: Human breast adipose-derived stem cells retain stem cell characteristics after expansion in culture through passage 3 and serve as a feasible source of cells for cartilage regeneration in vitro. Chondrogenesis in HBASCs was found to be prominent

Reconstructing Dynamic Promoter Activity Profiles from Reporter Gene Data.

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Kannan, Soumya; Sams, Thomas; Maury, Jérôme; Workman, Christopher T

2018-03-16

Accurate characterization of promoter activity is important when designing expression systems for systems biology and metabolic engineering applications. Promoters that respond to changes in the environment enable the dynamic control of gene expression without the necessity of inducer compounds, for example. However, the dynamic nature of these processes poses challenges for estimating promoter activity. Most experimental approaches utilize reporter gene expression to estimate promoter activity. Typically the reporter gene encodes a fluorescent protein that is used to infer a constant promoter activity despite the fact that the observed output may be dynamic and is a number of steps away from the transcription process. In fact, some promoters that are often thought of as constitutive can show changes in activity when growth conditions change. For these reasons, we have developed a system of ordinary differential equations for estimating dynamic promoter activity for promoters that change their activity in response to the environment that is robust to noise and changes in growth rate. Our approach, inference of dynamic promoter activity (PromAct), improves on existing methods by more accurately inferring known promoter activity profiles. This method is also capable of estimating the correct scale of promoter activity and can be applied to quantitative data sets to estimate quantitative rates.

Epigenetic transgenerational actions of vinclozolin on promoter regions of the sperm epigenome.

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Carlos Guerrero-Bosagna

2010-09-01

Full Text Available Previous observations have demonstrated that embryonic exposure to the endocrine disruptor vinclozolin during gonadal sex determination promotes transgenerational adult onset disease such as male infertility, kidney disease, prostate disease, immune abnormalities and tumor development. The current study investigates genome-wide promoter DNA methylation alterations in the sperm of F3 generation rats whose F0 generation mother was exposed to vinclozolin. A methylated DNA immunoprecipitation with methyl-cytosine antibody followed by a promoter tilling microarray (MeDIP-Chip procedure was used to identify 52 different regions with statistically significant altered methylation in the sperm promoter epigenome. Mass spectrometry bisulfite analysis was used to map the CpG DNA methylation and 16 differential DNA methylation regions were confirmed, while the remainder could not be analyzed due to bisulfite technical limitations. Analysis of these validated regions identified a consensus DNA sequence (motif that associated with 75% of the promoters. Interestingly, only 16.8% of a random set of 125 promoters contained this motif. One candidate promoter (Fam111a was found to be due to a copy number variation (CNV and not a methylation change, suggesting initial alterations in the germline epigenome may promote genetic abnormalities such as induced CNV in later generations. This study identifies differential DNA methylation sites in promoter regions three generations after the initial exposure and identifies common genome features present in these regions. In addition to primary epimutations, a potential indirect genetic abnormality was identified, and both are postulated to be involved in the epigenetic transgenerational inheritance observed. This study confirms that an environmental agent has the ability to induce epigenetic transgenerational changes in the sperm epigenome.

Epigenetic transgenerational actions of vinclozolin on promoter regions of the sperm epigenome.

Science.gov (United States)

Guerrero-Bosagna, Carlos; Settles, Matthew; Lucker, Ben; Skinner, Michael K

2010-09-30

Previous observations have demonstrated that embryonic exposure to the endocrine disruptor vinclozolin during gonadal sex determination promotes transgenerational adult onset disease such as male infertility, kidney disease, prostate disease, immune abnormalities and tumor development. The current study investigates genome-wide promoter DNA methylation alterations in the sperm of F3 generation rats whose F0 generation mother was exposed to vinclozolin. A methylated DNA immunoprecipitation with methyl-cytosine antibody followed by a promoter tilling microarray (MeDIP-Chip) procedure was used to identify 52 different regions with statistically significant altered methylation in the sperm promoter epigenome. Mass spectrometry bisulfite analysis was used to map the CpG DNA methylation and 16 differential DNA methylation regions were confirmed, while the remainder could not be analyzed due to bisulfite technical limitations. Analysis of these validated regions identified a consensus DNA sequence (motif) that associated with 75% of the promoters. Interestingly, only 16.8% of a random set of 125 promoters contained this motif. One candidate promoter (Fam111a) was found to be due to a copy number variation (CNV) and not a methylation change, suggesting initial alterations in the germline epigenome may promote genetic abnormalities such as induced CNV in later generations. This study identifies differential DNA methylation sites in promoter regions three generations after the initial exposure and identifies common genome features present in these regions. In addition to primary epimutations, a potential indirect genetic abnormality was identified, and both are postulated to be involved in the epigenetic transgenerational inheritance observed. This study confirms that an environmental agent has the ability to induce epigenetic transgenerational changes in the sperm epigenome.

Optimal pricing and promotional effort control policies for a new product growth in segmented market

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Jha P.C.

2015-01-01

Full Text Available Market segmentation enables the marketers to understand and serve the customers more effectively thereby improving company’s competitive position. In this paper, we study the impact of price and promotion efforts on evolution of sales intensity in segmented market to obtain the optimal price and promotion effort policies. Evolution of sales rate for each segment is developed under the assumption that marketer may choose both differentiated as well as mass market promotion effort to influence the uncaptured market potential. An optimal control model is formulated and a solution method using Maximum Principle has been discussed. The model is extended to incorporate budget constraint. Model applicability is illustrated by a numerical example. P.C. Jha, P. Manik, K. Chaudhary, R. Cambini / Optimal Pricing and Promotional 2 Since the discrete time data is available, the formulated model is discretized. For solving the discrete model, differential evolution algorithm is used.

Effect of TCEA3 on the differentiation of bovine skeletal muscle satellite cells

International Nuclear Information System (INIS)

Zhu, Yue; Tong, Hui-Li; Li, Shu-Feng; Yan, Yun-Qin

2017-01-01

Bovine muscle-derived satellite cells (MDSCs) are important for animal growth. In this study, the effect of transcription elongation factor A3 (TCEA3) on bovine MDSC differentiation was investigated. Western blotting, immunofluorescence assays, and cytoplasmic and nuclear protein isolation and purification techniques were used to determine the expression pattern and protein localization of TCEA3 in bovine MDSCs during in vitro differentiation. TCEA3 expression was upregulated using the CRISPR/Cas9 technique to study its effects on MDSC differentiation in vitro. TCEA3 expression gradually increased during the in vitro differentiation of bovine MDSCs and peaked on the 5th day of differentiation. TCEA3 was mainly localized in the cytoplasm of bovine MDSCs, and its expression was not detected in the nucleus. The level of TCEA3 was relatively higher in myotubes at a higher degree of differentiation than during early differentiation. After transfection with a TCEA3-activating plasmid vector (TCEA3 overexpression) for 24 h, the myotube fusion rate, number of myotubes, and expression levels of the muscle differentiation-related loci myogenin (MYOG) and myosin heavy chain 3 (MYH3) increased significantly during the in vitro differentiation of bovine MDSCs. After transfection with a TCEA3-inhibiting plasmid vector for 24 h, the myotube fusion rate, number of myotubes, and expression levels of MYOG and MYH3 decreased significantly. Our results indicated, for the first time, that TCEA3 promotes the differentiation of bovine MDSCs and have implications for meat production and animal rearing. - Highlights: • Muscle-derived satellite cell differentiation is promoted by TCEA3. • TCEA3 protein was localized in the cytoplasm, but not nuclei of bovine MDSCs. • TCEA3 levels increased as myotube differentiation increased. • TCEA3 affected myotube fusion, myotube counts, and MYOG and MYH3 levels.

Promoter characteristics of two cyp19 genes differentially expressed in the brain and ovary of teleost fish.

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Tchoudakova, A; Kishida, M; Wood, E; Callard, G V

2001-11-01

Teleost fish are characterized by exceptionally high levels of neural estrogen biosynthesis when compared with the brains of other vertebrates or to the ovaries of the same fish. Two P450arom mRNAs which derive from separate gene loci (cyp19a and cyp19b) are differentially expressed in brain (b>a) and ovary (a>b) and have a different developmental program (b>a) and estrogen upregulation (b only). A polymerase chain reaction (PCR)-based genomic walking strategy was used to isolate the 5'-flanking regions of the goldfish (Carassius auratus) cyp19 genes. Sequence analysis of the cyp19b gene approximately 1.8 kb upstream of the transcription start site revealed a TATA box at nucleotide (nt) -30, two estrogen responsive elements (EREs; nt -351 and -211) and a consensus binding site (NBRE) for nerve growth factor inducible-B protein (NGFI-B/Nur77) at -286, which includes another ERE half-site. Also present were a sequence at nt -399 (CCCTCCT) required for neural specificity of the zebrafish GATA-2 gene, and 16 copies of an SRY/SOX binding motif. The 5'-flanking region ( approximately 1.0 kb) of the cyp19a gene had TATA (nt -48) and CAAT (nt -71) boxes, a steroidogenic factor-1 (SF-1) binding site (nt -265), eight copies of the SRY/SOX motif, and two copies of a recognition site for binding the arylhydrocarbon receptor (AhR)/AhR nuclear translocator factor (ARNT) heterodimer. Both genes had elements previously identified in the brain specific exon I promoter of the mouse aromatase gene. Cyp19a- and -b/luciferase constructs showed basal promoter activity in aromatase-expressing rodent pituitary (GH3) cells, but differences (a>b) did not reflect expression in fish pituitary in vivo (b>a), implying a lack of appropriate cell factors. Consistent with the onset of cyp19b expression in zebrafish embryos, microinjection of a green fluorescent protein (GFP) reporter plasmid into fertilized eggs revealed labeling in neural tissues at 30-48 h post-fertilization (hpf), most

Pulsed electromagnetic fields promote the proliferation and differentiation of osteoblasts by reinforcing intracellular calcium transients.

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Tong, Jie; Sun, Lijun; Zhu, Bin; Fan, Yun; Ma, Xingfeng; Yu, Liyin; Zhang, Jianbao

2017-10-01

Pulsed electromagnetic fields (PEMF) can be used to treat bone-related diseases, but the underlying mechanism remains unclear, especially the process by which PEMFs initiate biological effects. In this study, we demonstrated the effects of PEMF on proliferation and differentiation of osteoblasts using the model of calcium transients induced by high extracellular calcium. Our results showed that PEMF can increase both the percentage of responding cells and amplitude of intracellular calcium transients induced by high extracellular calcium stimulation. Compared with corresponding extracellular calcium levels, PEMF stimulation increased proliferation and differentiation of osteoblasts and related gene expressions, such as insulin-like growth factor 1 (IGF-1), alkaline phosphatase (ALP), runt-related transcription factor 2 (Runx2), and osteocalcin (OCN), which can be completely abolished by BAPTA-AM. Moreover, PEMF did not affect proliferation and differentiation of osteoblasts if no intracellular calcium transient was present in osteoblasts during PEMF exposure. Our results revealed that PEMF affects osteoblast proliferation and differentiation through enhanced intracellular calcium transients, which provided a cue to treat bone-related diseases with PEMF. Bioelectromagnetics. 38:541-549, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Function of caspase-14 in trophoblast differentiation

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Charles Adrian K

2009-09-01

Full Text Available Abstract Background Within the human placenta, the cytotrophoblast consists of a proliferative pool of progenitor cells which differentiate to replenish the overlying continuous, multi-nucleated syncytiotrophoblast, which forms the barrier between the maternal and fetal tissues. Disruption to trophoblast differentiation and function may result in impaired fetal development and preeclampsia. Caspase-14 expression is limited to barrier forming tissues. It promotes keratinocyte differentiation by cleaving profilaggrin to stabilise keratin intermediate filaments, and indirectly providing hydration and UV protection. However its role in the trophoblast remains unexplored. Methods Using RNA Interference the reaction of control and differentiating trophoblastic BeWo cells to suppressed caspase-14 was examined for genes pertaining to hormonal, cell cycle and cytoskeletal pathways. Results Transcription of hCG, KLF4 and cytokeratin-18 were increased following caspase-14 suppression suggesting a role for caspase-14 in inhibiting their pathways. Furthermore, hCG, KLF4 and cytokeratin-18 protein levels were disrupted. Conclusion Since expression of these molecules is normally increased with trophoblast differentiation, our results imply that caspase-14 inhibits trophoblast differentiation. This is the first functional study of this unusual member of the caspase family in the trophoblast, where it has a different function than in the epidermis. This knowledge of the molecular underpinnings of trophoblast differentiation may instruct future therapies of trophoblast disease.

Role of human amnion-derived mesenchymal stem cells in promoting osteogenic differentiation by influencing p38 MAPK signaling in lipopolysaccharide -induced human bone marrow mesenchymal stem cells

International Nuclear Information System (INIS)

Wang, Yuli; Wu, Hongxia; Shen, Ming; Ding, Siyang; Miao, Jing; Chen, Ning

2017-01-01

Periodontitis is a chronic inflammatory disease induced by bacterial pathogens, which not only affect connective tissue attachments but also cause alveolar bone loss. In this study, we investigated the anti-inflammatory effects of Human amnion-derived mesenchymal stem cells (HAMSCs) on human bone marrow mesenchymal stem cells (HBMSCs) under lipopolysaccharide (LPS)-induced inflammatory conditions. Proliferation levels were measured by flow cytometry and immunofluorescence staining of 5-ethynyl-2′-deoxyuridine (EdU). Osteoblastic differentiation and mineralization were investigated using chromogenic alkaline phosphatase activity (ALP) activity substrate assays, Alizarin red S staining, and RT-PCR analysis of HBMSCs osteogenic marker expression. Oxidative stress induced by LPS was investigated by assaying reactive oxygen species (ROS) level and superoxide dismutase (SOD) activity. Here, we demonstrated that HAMSCs increased the proliferation, osteoblastic differentiation, and SOD activity of LPS-induced HBMSCs, and down-regulated the ROS level. Moreover, our results suggested that the activation of p38 MAPK signal transduction pathway is essential for reversing the LPS-induced bone-destructive processes. SB203580, a selective inhibitor of p38 MAPK signaling, significantly suppressed the anti-inflammatory effects in HAMSCs. In conclusion, HAMSCs show a strong potential in treating inflammation-induced bone loss by influencing p38 MAPK signaling. - Highlights: • LPS inhibites osteogenic differentiation in HBMSCs via suppression of p38 MAPK signaling pathway. • HAMSCs promote LPS-induced HBMSCs osteogenic differentiation through p38 MAPK signaling pathway. • HAMSCs reverse LPS-induced oxidative stress in LPS-induced HBMSCs through p38 MAPK signaling pathway.

The Effects of Brand Loyalty on Competitive Price Promotional Strategies

OpenAIRE

Jagmohan S. Raju; V. Srinivasan; Rajiv Lal

1990-01-01

This paper analyzes the role played by brand loyalty in determining optimal price promotional strategies used by firms in a competitive setting. (Loyalty is operationalized as the minimum price differential needed before consumers who prefer one brand switch to another brand.) Our objective is to examine how loyalties toward the competing brands influence whether or not firms would use price promotions in a product category. We also examine how loyalty differences lead to variations in the de...

The impact of using the internet in promoting Romanian industry

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Carmen Adina PASTIU

2012-03-01

Full Text Available Central element of the marketing mix, advertising can differentiate the companies in Romanian industry through the strategy used by each company. The present paper summarises the results of a qualitative research conducted in 15 companies acting in food, mechanical processing, textile, leather, and footwear industries. Throughout this study the benefits of using online promotion were highlighted and a diagnosis regarding the use of the Internet for promoting products in Romanian industry was performed.

[Comprehensive regulation effect of traditional Chinese medicine on proliferation and differentiation of neural stem cells].

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Wang, Hong-Jin; Li, Jing-Jing; Ke, Hui; Xu, Xiao-Yu

2017-11-01

Since the discovery of neural stem cells(NSCs) in embryonic and adult mammalian central nervous systems, new approaches for proliferation and differentiation of NSCs have been put forward. One of the approaches to promote the clinical application of NSCs is to search effective methods to regulate the proliferation and differentiation. This problem is urgently to be solved in the medical field. Previous studies have shown that traditional Chinese medicine could promote the proliferation and differentiation of NSCs by regulating the relevant signaling pathway in vivo and in vitro. Domestic and foreign literatures for regulating the proliferation and differentiation of neural stem cells in recent 10 years and the reports for their target and signaling pathways were analyzed in this paper. Traditional Chinese medicine could regulate the proliferation and differentiation of NSCs through signaling pathways of Notch, PI3K/Akt, Wnt/β-catenin and GFs. However, studies about NSCs and traditional Chinese medicine should be further deepened; the mechanism of multiple targets and the comprehensive regulation function of traditional Chinese medicine should be clarified. Copyright© by the Chinese Pharmaceutical Association.

Functional analysis of human and chimpanzee promoters.

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Heissig, Florian; Krause, Johannes; Bryk, Jaroslaw; Khaitovich, Philipp; Enard, Wolfgang; Pääbo, Svante

2005-01-01

It has long been argued that changes in gene expression may provide an additional and crucial perspective on the evolutionary differences between humans and chimpanzees. To investigate how often expression differences seen in tissues are caused by sequence differences in the proximal promoters, we tested the expression activity in cultured cells of human and chimpanzee promoters from genes that differ in mRNA expression between human and chimpanzee tissues. Twelve promoters for which the corresponding gene had been shown to be differentially expressed between humans and chimpanzees in liver or brain were tested. Seven showed a significant difference in activity between the human promoter and the orthologous chimpanzee promoter in at least one of the two cell lines used. However, only three of them showed a difference in the same direction as in the tissues. Differences in proximal promoter activity are likely to be common between humans and chimpanzees, but are not linked in a simple fashion to gene-expression levels in tissues. This suggests that several genetic differences between humans and chimpanzees might be responsible for a single expression difference and thus that relevant expression differences between humans and chimpanzees will be difficult to predict from cell culture experiments or DNA sequences.

Altered binding of human histone gene transcription factors during the shutdown of proliferation and onset of differentiation in HL-60 cells

International Nuclear Information System (INIS)

Stein, G.; Lian, J.; Stein, J.; Shalhoub, V.; Wright, K.; Pauli, U.; Van Wijnen, A.; Briggs, R.

1989-01-01

Two sites of protein-DNA interaction have been identified in vivo and in vitro in the proximal promoter regions of an H4 and an H3 human histone gene. In proliferating cells, these genes are transcribed throughout the cell cycle, and both the more distal site I and the proximal site II are occupied by promoter-binding factors. In this report the authors demonstrate that during the shutdown of proliferation and onset of differentiation of the human promyelocytic leukemia cell line HL-60 into cells that exhibit phenotypic properties of monocytes, histone gene expression is down-regulated at the level of transcription. In vivo occupancy of site I by promoter factors persists in the differentiated HL-60 cells, but protein-DNA interactions at site II are selectively lost. Furthermore, in vitro binding activity of the site II promoter factor HiNF-D is lost in differentiated cells, and nuclear extracts from differentiated cells do not support in vitro transcription of these histone genes. The results suggest that the interaction of HiNF-D with proximal promoter site II sequences plays a primary role in rendering cell growth-regulated histone genes transcribable in proliferating cells. It appears that while cell-cycle control of histone gene expression is mediated by both transcription and mRNA stability, with the shutdown of proliferation and onset of differentiation, histone gene expression is regulated at the transcriptional level

Functional analysis of the OCA-B promoter.

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Stevens, S; Wang, L; Roeder, R G

2000-06-15

OCA-B was identified as a B cell-specific coactivator that functions with either Oct-1 or Oct-2 to mediate efficient cell type-specific transcription via the octamer site (ATGCAAAT) both in vivo and in vitro. Mice lacking OCA-B exhibit normal Ag-independent B cell maturation. In contrast, Ag-dependent functions, including production of secondary Ig isotypes and germinal center formation, are greatly affected. To better understand OCA-B expression and, ultimately, the defects observed in the OCA-B knockout mice, we have cloned the OCA-B promoter and examined its function in both transformed and primary B cells. We show here that the OCA-B promoter is developmentally regulated, with activity increasing throughout B cell differentiation. Through physical and functional assays, we have found an activating transcription factor/cAMP response element binding protein binding site (or cAMP response element) that is crucial for OCA-B promoter activity. Furthermore, we demonstrate that IL-4 and anti-CD40 induce both the OCA-B promoter and octamer-dependent promoters, thus implicating OCA-B in B cell signaling events in the nucleus.

Irisin Enhances Osteoblast Differentiation In Vitro

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Graziana Colaianni

2014-01-01

Full Text Available It has been recently demonstrated that exercise activity increases the expression of the myokine Irisin in skeletal muscle, which is able to drive the transition of white to brown adipocytes, likely following a phenomenon of transdifferentiation. This new evidence supports the idea that muscle can be considered an endocrine organ, given its ability to target adipose tissue by promoting energy expenditure. In accordance with these new findings, we hypothesized that Irisin is directly involved in bone metabolism, demonstrating its ability to increase the differentiation of bone marrow stromal cells into mature osteoblasts. Firstly, we confirmed that myoblasts from mice subjected to 3 weeks of free wheel running increased Irisin expression compared to nonexercised state. The conditioned media (CM collected from myoblasts of exercised mice induced osteoblast differentiation in vitro to a greater extent than those of mice housed in resting conditions. Furthermore, the differentiated osteoblasts increased alkaline phosphatase and collagen I expression by an Irisin-dependent mechanism. Our results show, for the first time, that Irisin directly targets osteoblasts, enhancing their differentiation. This finding advances notable perspectives in future studies which could satisfy the ongoing research of exercise-mimetic therapies with anabolic action on the skeleton.

Biomimetic hydrogels direct spinal progenitor cell differentiation and promote functional recovery after spinal cord injury

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Geissler, Sydney A.; Sabin, Alexandra L.; Besser, Rachel R.; Gooden, Olivia M.; Shirk, Bryce D.; Nguyen, Quan M.; Khaing, Zin Z.; Schmidt, Christine E.

2018-04-01

Objective. Demyelination that results from disease or traumatic injury, such as spinal cord injury (SCI), can have a devastating effect on neural function and recovery. Many researchers are examining treatments to minimize demyelination by improving oligodendrocyte availability in vivo. Transplantation of stem and oligodendrocyte progenitor cells is a promising option, however, trials are plagued by undirected differentiation. Here we introduce a biomaterial that has been optimized to direct the differentiation of neural progenitor cells (NPCs) toward oligodendrocytes as a cell delivery vehicle after SCI. Approach. A collagen-based hydrogel was modified to mimic the mechanical properties of the neonatal spinal cord, and components present in the developing extracellular matrix were included to provide appropriate chemical cues to the NPCs to direct their differentiation toward oligodendrocytes. The hydrogel with cells was then transplanted into a unilateral cervical contusion model of SCI to examine the functional recovery with this treatment. Six behavioral tests and histological assessment were performed to examine the in vivo response to this treatment. Main results. Our results demonstrate that we can achieve a significant increase in oligodendrocyte differentiation of NPCs compared to standard culture conditions using a three-component biomaterial composed of collagen, hyaluronic acid, and laminin that has mechanical properties matched to those of neonatal neural tissue. Additionally, SCI rats with hydrogel transplants, with and without NPCs, showed functional recovery. Animals transplanted with hydrogels with NPCs showed significantly increased functional recovery over six weeks compared to the media control group. Significance. The three-component hydrogel presented here has the potential to provide cues to direct differentiation in vivo to encourage regeneration of the central nervous system.

Myostatin acts as an autocrine/paracrine negative regulator in myoblast differentiation from human induced pluripotent stem cells

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Gao, Fei; Kishida, Tsunao; Ejima, Akika [Department of Immunology, Kyoto Prefectural University of Medicine, Kyoto (Japan); Gojo, Satoshi [Department of Cardiac Support, Kyoto Prefectural University of Medicine, Kyoto (Japan); Mazda, Osam, E-mail: mazda@koto.kpu-m.ac.jp [Department of Immunology, Kyoto Prefectural University of Medicine, Kyoto (Japan)

2013-02-08

Highlights: ► iPS-derived cells express myostatin and its receptor upon myoblast differentiation. ► Myostatin inhibits myoblast differentiation by inhibiting MyoD and Myo5a induction. ► Silencing of myostatin promotes differentiation of human iPS cells into myoblasts. -- Abstract: Myostatin, also known as growth differentiation factor (GDF-8), regulates proliferation of muscle satellite cells, and suppresses differentiation of myoblasts into myotubes via down-regulation of key myogenic differentiation factors including MyoD. Recent advances in stem cell biology have enabled generation of myoblasts from pluripotent stem cells, but it remains to be clarified whether myostatin is also involved in regulation of artificial differentiation of myoblasts from pluripotent stem cells. Here we show that the human induced pluripotent stem (iPS) cell-derived cells that were induced to differentiate into myoblasts expressed myostatin and its receptor during the differentiation. An addition of recombinant human myostatin (rhMyostatin) suppressed induction of MyoD and Myo5a, resulting in significant suppression of myoblast differentiation. The rhMyostatin treatment also inhibited proliferation of the cells at a later phase of differentiation. RNAi-mediated silencing of myostatin promoted differentiation of human iPS-derived embryoid body (EB) cells into myoblasts. These results strongly suggest that myostatin plays an important role in regulation of myoblast differentiation from iPS cells of human origin. The present findings also have significant implications for potential regenerative medicine for muscular diseases.

Myostatin acts as an autocrine/paracrine negative regulator in myoblast differentiation from human induced pluripotent stem cells

International Nuclear Information System (INIS)

Gao, Fei; Kishida, Tsunao; Ejima, Akika; Gojo, Satoshi; Mazda, Osam

2013-01-01

Highlights: ► iPS-derived cells express myostatin and its receptor upon myoblast differentiation. ► Myostatin inhibits myoblast differentiation by inhibiting MyoD and Myo5a induction. ► Silencing of myostatin promotes differentiation of human iPS cells into myoblasts. -- Abstract: Myostatin, also known as growth differentiation factor (GDF-8), regulates proliferation of muscle satellite cells, and suppresses differentiation of myoblasts into myotubes via down-regulation of key myogenic differentiation factors including MyoD. Recent advances in stem cell biology have enabled generation of myoblasts from pluripotent stem cells, but it remains to be clarified whether myostatin is also involved in regulation of artificial differentiation of myoblasts from pluripotent stem cells. Here we show that the human induced pluripotent stem (iPS) cell-derived cells that were induced to differentiate into myoblasts expressed myostatin and its receptor during the differentiation. An addition of recombinant human myostatin (rhMyostatin) suppressed induction of MyoD and Myo5a, resulting in significant suppression of myoblast differentiation. The rhMyostatin treatment also inhibited proliferation of the cells at a later phase of differentiation. RNAi-mediated silencing of myostatin promoted differentiation of human iPS-derived embryoid body (EB) cells into myoblasts. These results strongly suggest that myostatin plays an important role in regulation of myoblast differentiation from iPS cells of human origin. The present findings also have significant implications for potential regenerative medicine for muscular diseases

Monocytes/Macrophages Upregulate the Hyaluronidase HYAL1 and Adapt Its Subcellular Trafficking to Promote Extracellular Residency upon Differentiation into Osteoclasts.

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Emeline Puissant

Full Text Available Osteoclasts are giant bone-resorbing cells originating from monocytes/macrophages. During their differentiation, they overexpress two lysosomal enzymes, cathepsin K and TRAP, which are secreted into the resorption lacuna, an acidified sealed area in contact with bone matrix where bone degradation takes place. Here we report that the acid hydrolase HYAL1, a hyaluronidase able to degrade the glycosaminoglycans hyaluronic acid (HA and chondroitin sulfate, is also upregulated upon osteoclastogenesis. The mRNA expression and protein level of HYAL1 are markedly increased in osteoclasts differentiated from RAW264.7 mouse macrophages or primary mouse bone marrow monocytes compared to these precursor cells. As a result, the HYAL1-mediated HA hydrolysis ability of osteoclasts is strongly enhanced. Using subcellular fractionation, we demonstrate that HYAL1 proteins are sorted to the osteoclast lysosomes even though, in contrast to cathepsin K and TRAP, HYAL1 is poorly mannose 6-phosphorylated. We reported previously that macrophages secrete HYAL1 proforms by constitutive secretion, and that these are recaptured by the cell surface mannose receptor, processed in endosomes and sorted to lysosomes. Present work highlights that osteoclasts secrete HYAL1 in two ways, through lysosomal exocytosis and constitutive secretion, and that these cells promote the extracellular residency of HYAL1 through downregulation of the mannose receptor. Interestingly, the expression of the other main hyaluronidase, HYAL2, and of lysosomal exoglycosidases involved in HA degradation, does not increase similarly to HYAL1 upon osteoclastogenesis. Taken together, these findings point out the predominant involvement of HYAL1 in bone HA metabolism and perhaps bone remodeling via the resorption lacuna.

RUNX1 suppression induces megakaryocytic differentiation of UT-7/GM cells

International Nuclear Information System (INIS)

Nagai, Ryohei; Matsuura, Eri; Hoshika, Yusuke; Nakata, Emi; Nagura, Hironori; Watanabe, Ayako; Komatsu, Norio; Okada, Yoshiaki; Doi, Takefumi

2006-01-01

The transcription factor RUNX1 plays a crucial role in hematopoiesis. RUNX1 regulates both differentiation and proliferation of hematopoietic cells. Several reports have shown that RUNX1 participates in megakaryopoiesis, which is a process that leads to formation of platelets. However, to date, the mechanisms by which this occurs have not been fully elucidated. In the present study, we investigated whether siRNA-mediated depletion of RUNX1 affected megakaryopoiesis of UT-7/GM cells. The depletion of RUNX1 in UT-7/GM cells resulted in up-regulation of the expression of megakaryocytic markers and polyploidization, while cell proliferation was down-regulated. Furthermore, the overexpression of RUNX1 decreased the activity of megakaryocytic gene promoters. These results suggest that RUNX1 down-regulates terminal differentiation of megakaryocytes and promotes proliferation of megakaryocytic progenitors

Epigenetic Library Screen Identifies Abexinostat as Novel Regulator of Adipocytic and Osteoblastic Differentiation of Human Skeletal (Mesenchymal) Stem Cells

Science.gov (United States)

Ali, Dalia; Hamam, Rimi; Alfayez, Musaed; Kassem, Moustapha; Aldahmash, Abdullah

2016-01-01

The epigenetic mechanisms promoting lineage-specific commitment of human skeletal (mesenchymal or stromal) stem cells (hMSCs) into adipocytes or osteoblasts are still not fully understood. Herein, we performed an epigenetic library functional screen and identified several novel compounds, including abexinostat, which promoted adipocytic and osteoblastic differentiation of hMSCs. Using gene expression microarrays, chromatin immunoprecipitation for H3K9Ac combined with high-throughput DNA sequencing (ChIP-seq), and bioinformatics, we identified several key genes involved in regulating stem cell proliferation and differentiation that were targeted by abexinostat. Concordantly, ChIP-quantitative polymerase chain reaction revealed marked increase in H3K9Ac epigenetic mark on the promoter region of AdipoQ, FABP4, PPARγ, KLF15, CEBPA, SP7, and ALPL in abexinostat-treated hMSCs. Pharmacological inhibition of focal adhesion kinase (PF-573228) or insulin-like growth factor-1R/insulin receptor (NVP-AEW51) signaling exhibited significant inhibition of abexinostat-mediated adipocytic differentiation, whereas inhibition of WNT (XAV939) or transforming growth factor-β (SB505124) signaling abrogated abexinostat-mediated osteogenic differentiation of hMSCs. Our findings provide insight into the understanding of the relationship between the epigenetic effect of histone deacetylase inhibitors, transcription factors, and differentiation pathways governing adipocyte and osteoblast differentiation. Manipulating such pathways allows a novel use for epigenetic compounds in hMSC-based therapies and tissue engineering. Significance This unbiased epigenetic library functional screen identified several novel compounds, including abexinostat, that promoted adipocytic and osteoblastic differentiation of human skeletal (mesenchymal or stromal) stem cells (hMSCs). These data provide new insight into the understanding of the relationship between the epigenetic effect of histone deacetylase

Synthetic Glycopolymers for Highly Efficient Differentiation of Embryonic Stem Cells into Neurons: Lipo- or Not?

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Liu, Qi; Lyu, Zhonglin; Yu, You; Zhao, Zhen-Ao; Hu, Shijun; Yuan, Lin; Chen, Gaojian; Chen, Hong

2017-04-05

To realize the potential application of embryonic stem cells (ESCs) for the treatment of neurodegenerative diseases, it is a prerequisite to develop an effective strategy for the neural differentiation of ESCs so as to obtain adequate amount of neurons. Considering the efficacy of glycosaminoglycans (GAG) and their disadvantages (e.g., structure heterogeneity and impurity), GAG-mimicking glycopolymers (designed polymers containing functional units similar to natural GAG) with or without phospholipid groups were synthesized in the present work and their ability to promote neural differentiation of mouse ESCs (mESCs) was investigated. It was found that the lipid-anchored GAG-mimicking glycopolymers (lipo-pSGF) retained on the membrane of mESCs rather than being internalized by cells after 1 h of incubation. Besides, lipo-pSGF showed better activity in promoting neural differentiation. The expression of the neural-specific maker β3-tubulin in lipo-pSGF-treated cells was ∼3.8- and ∼1.9-fold higher compared to natural heparin- and pSGF-treated cells at day 14. The likely mechanism involved in lipo-pSGF-mediated neural differentiation was further investigated by analyzing its effect on fibroblast growth factor 2 (FGF2)-mediated extracellular signal-regulated kinases 1 and 2 (ERK1/2) signaling pathway which is important for neural differentiation of ESCs. Lipo-pSGF was found to efficiently bind FGF2 and enhance the phosphorylation of ERK1/2, thus promoting neural differentiation. These findings demonstrated that engineering of cell surface glycan using our synthetic lipo-glycopolymer is a highly efficient approach for neural differentiation of ESCs and this strategy can be applied for the regulation of other cellular activities mediated by cell membrane receptors.

Astrocytes from the contused spinal cord inhibit oligodendrocyte differentiation of adult oligodendrocyte precursor cells by increasing the expression of bone morphogenetic proteins.

Science.gov (United States)

Wang, Yaping; Cheng, Xiaoxin; He, Qian; Zheng, Yiyan; Kim, Dong H; Whittemore, Scott R; Cao, Qilin L

2011-04-20

Promotion of remyelination is an important therapeutic strategy to facilitate functional recovery after traumatic spinal cord injury (SCI). Transplantation of neural stem cells (NSCs) or oligodendrocyte precursor cells (OPCs) has been used to enhance remyelination after SCI. However, the microenvironment in the injured spinal cord is inhibitory for oligodendrocyte (OL) differentiation of NSCs or OPCs. Identifying the signaling pathways that inhibit OL differentiation in the injured spinal cord could lead to new therapeutic strategies to enhance remyelination and functional recovery after SCI. In the present study, we show that reactive astrocytes from the injured rat spinal cord or their conditioned media inhibit OL differentiation of adult OPCs with concurrent promotion of astrocyte differentiation. The expression of bone morphogenetic proteins (BMP) is dramatically increased in the reactive astrocytes and their conditioned media. Importantly, blocking BMP activity by BMP receptor antagonist, noggin, reverse the effects of active astrocytes on OPC differentiation by increasing the differentiation of OL from OPCs while decreasing the generation of astrocytes. These data indicate that the upregulated bone morphogenetic proteins in the reactive astrocytes are major factors to inhibit OL differentiation of OPCs and to promote its astrocyte differentiation. These data suggest that manipulation of BMP signaling in the endogenous or grafted NSCs or OPCs may be a useful therapeutic strategy to increase their OL differentiation and remyelination and enhance functional recovery after SCI.

Cap-proximal nucleotides via differential eIF4E binding and alternative promoter usage mediate translational response to energy stress.

Science.gov (United States)

Tamarkin-Ben-Harush, Ana; Vasseur, Jean-Jacques; Debart, Françoise; Ulitsky, Igor; Dikstein, Rivka

2017-02-08

Transcription start-site (TSS) selection and alternative promoter (AP) usage contribute to gene expression complexity but little is known about their impact on translation. Here we performed TSS mapping of the translatome following energy stress. Assessing the contribution of cap-proximal TSS nucleotides, we found dramatic effect on translation only upon stress. As eIF4E levels were reduced, we determined its binding to capped-RNAs with different initiating nucleotides and found the lowest affinity to 5'cytidine in correlation with the translational stress-response. In addition, the number of differentially translated APs was elevated following stress. These include novel glucose starvation-induced downstream transcripts for the translation regulators eIF4A and Pabp, which are also translationally-induced despite general translational inhibition. The resultant eIF4A protein is N-terminally truncated and acts as eIF4A inhibitor. The induced Pabp isoform has shorter 5'UTR removing an auto-inhibitory element. Our findings uncovered several levels of coordination of transcription and translation responses to energy stress.

Demethylating agent, 5-azacytidine, reverses differentiation of embryonic stem cells

International Nuclear Information System (INIS)

Tsuji-Takayama, Kazue; Inoue, Toshiya; Ijiri, Yoshihiro; Otani, Takeshi; Motoda, Ryuichi; Nakamura, Shuji; Orita, Kunzo

2004-01-01

The de novo methylation activity is essential for embryonic development as well as embryonic stem (ES) cell differentiation, where the intensive and extensive DNA methylation was detected. In this study, we investigated the effects of a demethylating agent, 5-azacytidine (5-AzaC), on differentiated ES cells in order to study the possibility of reversing the differentiation process. We first induced differentiation of ES cells by forming embryoid bodies, and then the cells were treated with 5-AzaC. The cells showed some undifferentiated features such as stem cell-like morphology with unclear cell-to-cell boundary and proliferative responsiveness to LIF. Moreover, 5-AzaC increased the expressions of ES specific markers, SSEA-1, and alkaline phosphatase activity as well as ES specific genes, Oct4, Nanog, and Sox2. We also found that 5-AzaC demethylated the promoter region of H19 gene, a typical methylated gene during embryonic differentiation. These results indicate that 5-AzaC reverses differentiation state of ES cells through its DNA demethylating activity to differentiation related genes

Effects of matrix elasticity and cell density on human mesenchymal stem cells differentiation.

Science.gov (United States)

Xue, Ruyue; Li, Julie Yi-Shuan; Yeh, Yiting; Yang, Li; Chien, Shu

2013-09-01

Human mesenchymal stem cells (hMSCs) can differentiate into various cell types, including osteogenic and chondrogenic cells. The matrix elasticity and cell seeding density are important factors in hMSCs differentiation. We cultured hMSCs at different seeding densities on polyacrylamide hydrogels with different stiffness corresponding to Young's moduli of 1.6 ± 0.3 and 40 ± 3.6 kPa. The promotion of osteogenic marker expression by hard gel is overridden by a high seeding density. Cell seeding density, however, did not influence the chondrogenic marker expressions induced by soft gel. These findings suggest that interplays between cell-matrix and cell-cell interactions contribute to hMSCs differentiation. The promotion of osteogenic differentiation on hard matrix was shown to be mediated through the Ras pathway. Inhibition of Ras (RasN17) significantly decreased ERK, Smad1/5/8 and AKT activation, and osteogenic markers expression. However, constitutively active Ras (RasV12) had little effect on osteogenic marker expression, suggesting that the Ras pathways are necessary but not sufficient for osteogenesis. Taken together, our results indicate that matrix elasticity and cell density are important microenvironmental cues driving hMSCs proliferation and differentiation. Copyright © 2013 Orthopaedic Research Society.

Developmental exposure to trichloroethylene promotes CD4+ T cell differentiation and hyperactivity in association with oxidative stress and neurobehavioral deficits in MRL+/+ mice

International Nuclear Information System (INIS)

Blossom, Sarah J.; Doss, Jason C.; Hennings, Leah J.; Jernigan, Stefanie; Melnyk, Stepan; James, S. Jill

2008-01-01

The non adult immune system is particularly sensitive to perinatal and early life exposures to environmental toxicants. The common environmental toxicant, trichloroethylene (TCE), was shown to increase CD4+ T cell production of the proinflammatory cytokine IFN-γ following a period of prenatal and lifetime exposure in autoimmune-prone MRL+/+ mice. In the current study, MRL+/+ mice were used to further examine the impact of TCE on the immune system in the thymus and periphery. Since there is considerable cross-talk between the immune system and the brain during development, the potential relationship between TCE and neurobehavioral endpoints were also examined. MRL+/+ mice were exposed to 0.1 mg/ml TCE (∼ 31 mg/kg/day) via maternal drinking water or direct exposure via the drinking water from gestation day 1 until postnatal day (PD) 42. TCE exposure did not impact gross motor skills but instead significantly altered social behaviors and promoted aggression associated with indicators of oxidative stress in brain tissues in male mice. The immunoregulatory effects of TCE involved a redox-associated promotion of T cell differentiation in the thymus that preceded the production of proinflammatory cytokines, IL-2, TNF-α, and IFN-γ by mature CD4+ T cells. The results demonstrated that developmental and early life TCE exposure modulated immune function and may have important implications for neurodevelopmental disorders

Hypoxia-induced pulmonary vascular remodeling requires recruitment of circulating mesenchymal precursors of a monocyte/macrophage lineage.

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Frid, Maria G; Brunetti, Jacqueline A; Burke, Danielle L; Carpenter, Todd C; Davie, Neil J; Reeves, John T; Roedersheimer, Mark T; van Rooijen, Nico; Stenmark, Kurt R

2006-02-01

Vascular remodeling in chronic hypoxic pulmonary hypertension includes marked fibroproliferative changes in the pulmonary artery (PA) adventitia. Although resident PA fibroblasts have long been considered the primary contributors to these processes, we tested the hypothesis that hypoxia-induced pulmonary vascular remodeling requires recruitment of circulating mesenchymal precursors of a monocyte/macrophage lineage, termed fibrocytes. Using two neonatal animal models (rats and calves) of chronic hypoxic pulmonary hypertension, we demonstrated a dramatic perivascular accumulation of mononuclear cells of a monocyte/macrophage lineage (expressing CD45, CD11b, CD14, CD68, ED1, ED2). Many of these cells produced type I collagen, expressed alpha-smooth muscle actin, and proliferated, thus exhibiting mesenchymal cell characteristics attributed to fibrocytes. The blood-borne origin of these cells was confirmed in experiments wherein circulating monocytes/macrophages of chronically hypoxic rats were in vivo-labeled with DiI fluorochrome via liposome delivery and subsequently identified in the remodeled pulmonary, but not systemic, arterial adventitia. The DiI-labeled cells that appeared in the vessel wall expressed monocyte/macrophage markers and procollagen. Selective depletion of this monocytic cell population, using either clodronate-liposomes or gadolinium chloride, prevented pulmonary adventitial remodeling (ie, production of collagen, fibronectin, and tenascin-C and accumulation of myofibroblasts). We conclude that circulating mesenchymal precursors of a monocyte/macrophage lineage, including fibrocytes, are essential contributors to hypoxia-induced pulmonary vascular remodeling.

Tendon and ligament as novel cell sources for engineering the knee meniscus.

Science.gov (United States)

Hadidi, P; Paschos, N K; Huang, B J; Aryaei, A; Hu, J C; Athanasiou, K A

2016-12-01

The application of cell-based therapies in regenerative medicine is hindered by the difficulty of acquiring adequate numbers of competent cells. For the knee meniscus in particular, this may be solved by harvesting tissue from neighboring tendons and ligaments. In this study, we have investigated the potential of cells from tendon and ligament, as compared to meniscus cells, to engineer scaffold-free self-assembling fibrocartilage. Self-assembling meniscus-shaped constructs engineered from a co-culture of articular chondrocytes and either meniscus, tendon, or ligament cells were cultured for 4 weeks with TGF-β1 in serum-free media. After culture, constructs were assessed for their mechanical properties, histological staining, gross appearance, and biochemical composition including cross-link content. Correlations were performed to evaluate relationships between biochemical content and mechanical properties. In terms of mechanical properties as well as biochemical content, constructs engineered using tenocytes and ligament fibrocytes were found to be equivalent or superior to constructs engineered using meniscus cells. Furthermore, cross-link content was found to be correlated with engineered tissue tensile properties. Tenocytes and ligament fibrocytes represent viable cell sources for engineering meniscus fibrocartilage using the self-assembling process. Due to greater cross-link content, fibrocartilage engineered with tenocytes and ligament fibrocytes may maintain greater tensile properties than fibrocartilage engineered with meniscus cells. Copyright © 2016 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

Injury-activated glial cells promote wound healing of the adult skin in mice.

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Parfejevs, Vadims; Debbache, Julien; Shakhova, Olga; Schaefer, Simon M; Glausch, Mareen; Wegner, Michael; Suter, Ueli; Riekstina, Una; Werner, Sabine; Sommer, Lukas

2018-01-16

Cutaneous wound healing is a complex process that aims to re-establish the original structure of the skin and its functions. Among other disorders, peripheral neuropathies are known to severely impair wound healing capabilities of the skin, revealing the importance of skin innervation for proper repair. Here, we report that peripheral glia are crucially involved in this process. Using a mouse model of wound healing, combined with in vivo fate mapping, we show that injury activates peripheral glia by promoting de-differentiation, cell-cycle re-entry and dissemination of the cells into the wound bed. Moreover, injury-activated glia upregulate the expression of many secreted factors previously associated with wound healing and promote myofibroblast differentiation by paracrine modulation of TGF-β signalling. Accordingly, depletion of these cells impairs epithelial proliferation and wound closure through contraction, while their expansion promotes myofibroblast formation. Thus, injury-activated glia and/or their secretome might have therapeutic potential in human wound healing disorders.

Single-step generation of gene knockout-rescue system in pluripotent stem cells by promoter insertion with CRISPR/Cas9.

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Matsunaga, Taichi; Yamashita, Jun K

2014-02-07

Specific gene knockout and rescue experiments are powerful tools in developmental and stem cell biology. Nevertheless, the experiments require multiple steps of molecular manipulation for gene knockout and subsequent rescue procedures. Here we report an efficient and single step strategy to generate gene knockout-rescue system in pluripotent stem cells by promoter insertion with CRISPR/Cas9 genome editing technology. We inserted a tetracycline-regulated inducible gene promoter (tet-OFF/TRE-CMV) upstream of the endogenous promoter region of vascular endothelial growth factor receptor 2 (VEGFR2/Flk1) gene, an essential gene for endothelial cell (EC) differentiation, in mouse embryonic stem cells (ESCs) with homologous recombination. Both homo- and hetero-inserted clones were efficiently obtained through a simple selection with a drug-resistant gene. The insertion of TRE-CMV promoter disrupted endogenous Flk1 expression, resulting in null mutation in homo-inserted clones. When the inserted TRE-CMV promoter was activated with doxycycline (Dox) depletion, Flk1 expression was sufficiently recovered from the downstream genomic Flk1 gene. Whereas EC differentiation was almost completely perturbed in homo-inserted clones, Flk1 rescue with TRE-CMV promoter activation restored EC appearance, indicating that phenotypic changes in EC differentiation can be successfully reproduced with this knockout-rescue system. Thus, this promoter insertion strategy with CRISPR/Cas9 would be a novel attractive method for knockout-rescue experiments. Copyright © 2014 Elsevier Inc. All rights reserved.

Study of the Role of siRNA Mediated Promoter Methylation in DNMT3B Knockdown and Alteration of Promoter Methylation of CDH1, GSTP1 Genes in MDA-MB -453 Cell Line.

Science.gov (United States)

Naghitorabi, Mojgan; Mir Mohammad Sadeghi, Hamid; Mohammadi Asl, Javad; Rabbani, Mohammad; Jafarian-Dehkordi, Abbas

2017-01-01

Promoter methylation is one of the main epigenetic mechanisms that leads to the inactivation of tumor suppressor genes during carcinogenesis. Due to the reversible nature of DNA methylation, many studies have been performed to correct theses epigenetic defects by inhibiting DNA methyltransferases (DNMTs). In this case novel therapeutics especially siRNA oligonucleotides have been used to specifically knock down the DNMTs at mRNA level. Also many studies have focused on transcriptional gene silencing in mammalian cells via siRNA mediated promoter methylation. The present study was designed to assess the role of siRNA mediated promoter methylation in DNMT3B knockdown and alteration of promoter methylation of Cadherin-1 (CDH1), Glutathione S-Transferase Pi 1(GSTP1), and DNMT3B genes in MDA-MB-453 cell line. MDA-MB-453 cells were transfected with siDNMT targeting DNMT3B promoter and harvested at 24 and 48 h post transfection to monitor gene silencing and promoter methylation respectively. DNMT3B expression was monitored by quantitative RT-PCR method. Promoter methylation was quantitatively evaluated using differential high resolution melting analysis. A non-significant 20% reduction in DNMT3B mRNA level was shown only after first transfection with siDNMT, which was not reproducible. Promoter methylation levels of DNMT3B, CDH1, and GSTP1 were detected at about 15%, 70% and 10% respectively, in the MDA-MB-453 cell line, with no significant change after transfection. Our results indicated that siDNMT sequence were not able to affect promoter methylation and silencing of DNMT3B in MDA-MB-453 cells. However, quantitation of methylation confirmed a hypermethylated phenotype at CDH1 and GSTP1 promoters as well as a differential methylation pattern at DNMT3B promoter in breast cancer.

Tlx3 exerts context-dependent transcriptional regulation and promotes neuronal differentiation from embryonic stem cells

OpenAIRE

Kondo, Takako; Sheets, Patrick L.; Zopf, David A.; Aloor, Heather L.; Cummins, Theodore R.; Chan, Rebecca J.; Hashino, Eri

2008-01-01

The T cell leukemia 3 (Tlx3) gene has been implicated in specification of glutamatergic sensory neurons in the spinal cord. In cranial sensory ganglia, Tlx3 is highly expressed in differentiating neurons during early embryogenesis. To study a role of Tlx3 during neural differentiation, mouse embryonic stem (ES) cells were transfected with a Tlx3 expression vector. ES cells stably expressing Tlx3 were grown in the presence or absence of a neural induction medium. In undifferentiated ES cells, ...

Activation of mitochondrial promoter PH-binding protein in a radio-resistant Chinese hamster cell strain associated with Bcl-2

International Nuclear Information System (INIS)

Roychoudhury, Paromita; Ghosh, Utpal; Bhattacharyya, Nitai P.; Chaudhuri, Keya

2006-01-01

The cellular response to ionizing radiation is mediated by a complex interaction of number of proteins involving different pathways. Previously, we have shown that up regulation of mitochondrial genes ND1, ND4, and COX1 transcribed from the heavy strand promoter (P H ) has been increased in a radio-resistant cell strain designated as M5 in comparison with the parental Chinese hamster V79 cells. These genes are also up regulated in Chinese hamster V79 cells VB13 that express exogenous human Bcl2. In the present study, the expression of the gene ND6 that is expressed from the light strand promoter (P L ) was found to be similar in both the cell lines, as determined by RT-PCR. To test the possibility that this differential expression of mitochondrial genes under these two promoters was mediated by differences in proteins' affinity to interact with these promoters, we have carried out electrophoretic mobility shift assay (EMSA) using mitochondrial cell extracts from these two cell lines. Our result of these experiments revealed that two different proteins formed complex with the synthetic promoters and higher amount of protein from M5 cell extracts interacted with the P H promoter in comparison to that observed with cell extracts from Chinese hamster V79 cells. The promoter-specific differential binding of proteins was also observed in VB13. These results showed that differential mitochondrial gene expression observed earlier in the radio-resistant M5 cells was due to enhanced interaction proteins with the promoters P H and mediated by the expression of Bcl2

A new module in neural differentiation control: two microRNAs upregulated by retinoic acid, miR-9 and -103, target the differentiation inhibitor ID2.

Directory of Open Access Journals (Sweden)

Daniela Annibali

Full Text Available The transcription factor ID2 is an important repressor of neural differentiation strongly implicated in nervous system cancers. MicroRNAs (miRNAs are increasingly involved in differentiation control and cancer development. Here we show that two miRNAs upregulated on differentiation of neuroblastoma cells--miR-9 and miR-103--restrain ID2 expression by directly targeting the coding sequence and 3' untranslated region of the ID2 encoding messenger RNA, respectively. Notably, the two miRNAs show an inverse correlation with ID2 during neuroblastoma cell differentiation induced by retinoic acid. Overexpression of miR-9 and miR-103 in neuroblastoma cells reduces proliferation and promotes differentiation, as it was shown to occur upon ID2 inhibition. Conversely, an ID2 mutant that cannot be targeted by either miRNA prevents retinoic acid-induced differentiation more efficient than wild-type ID2. These findings reveal a new regulatory module involving two microRNAs upregulated during neural differentiation that directly target expression of the key differentiation inhibitor ID2, suggesting that its alteration may be involved in neural cancer development.

Social deprivation and exposure to health promotion. A study of the distribution of health promotion resources to schools in England.

Science.gov (United States)

Chivu, Corina M; Reidpath, Daniel D

2010-08-10

Area deprivation is a known determinant of health. It is also known that area deprivation is associated with lower impact health promotion. It is less well known, however, whether deprived areas are less responsive to health promotion, or whether they are less exposed. Using data from a national, school-based campaign to promote vaccination against the human papilloma virus (HPV), the relationship between area deprivation and exposure was examined. Taking advantage of a health promotion campaign to provide information to schools about HPV vaccination, a cross sectional study was conducted to examine the relationship between area level, social deprivation, and take-up of (i.e., exposure to) available health promotion material. The sample was 4,750 schools across England, including government maintained and independent schools. The relationship between area deprivation and exposure was examined using bi- and multivariate logistic regression. It was found that schools in the least deprived quintile had 1.32 times the odds of requesting health promotion materials than schools in the most deprived areas (p = .01). This effect was independent of the school size, the type of school, and the geographic region. The relationship between area deprivation and the impact of health promotion may be due, at least in part, to differential levels of exposure. The study was limited in scope, pointing to the need for more research, but also points to potentially important policy implications.

Global mapping of cell type-specific open chromatin by FAIRE-seq reveals the regulatory role of the NFI family in adipocyte differentiation.

Directory of Open Access Journals (Sweden)

Hironori Waki

2011-10-01

Full Text Available Identification of regulatory elements within the genome is crucial for understanding the mechanisms that govern cell type-specific gene expression. We generated genome-wide maps of open chromatin sites in 3T3-L1 adipocytes (on day 0 and day 8 of differentiation and NIH-3T3 fibroblasts using formaldehyde-assisted isolation of regulatory elements coupled with high-throughput sequencing (FAIRE-seq. FAIRE peaks at the promoter were associated with active transcription and histone modifications of H3K4me3 and H3K27ac. Non-promoter FAIRE peaks were characterized by H3K4me1+/me3-, the signature of enhancers, and were largely located in distal regions. The non-promoter FAIRE peaks showed dynamic change during differentiation, while the promoter FAIRE peaks were relatively constant. Functionally, the adipocyte- and preadipocyte-specific non-promoter FAIRE peaks were, respectively, associated with genes up-regulated and down-regulated by differentiation. Genes highly up-regulated during differentiation were associated with multiple clustered adipocyte-specific FAIRE peaks. Among the adipocyte-specific FAIRE peaks, 45.3% and 11.7% overlapped binding sites for, respectively, PPARγ and C/EBPα, the master regulators of adipocyte differentiation. Computational motif analyses of the adipocyte-specific FAIRE peaks revealed enrichment of a binding motif for nuclear family I (NFI transcription factors. Indeed, ChIP assay showed that NFI occupy the adipocyte-specific FAIRE peaks and/or the PPARγ binding sites near PPARγ, C/EBPα, and aP2 genes. Overexpression of NFIA in 3T3-L1 cells resulted in robust induction of these genes and lipid droplet formation without differentiation stimulus. Overexpression of dominant-negative NFIA or siRNA-mediated knockdown of NFIA or NFIB significantly suppressed both induction of genes and lipid accumulation during differentiation, suggesting a physiological function of these factors in the adipogenic program. Together, our

Lactate induces osteoblast differentiation by stabilization of HIF1α.

Science.gov (United States)

Wu, Yu; Wang, Miaomiao; Feng, Haihua; Peng, Ying; Sun, Jieyun; Qu, Xiuxia; Li, Chunping

2017-09-05

Aerobic glycolysis is involved in osteoblast differentiation induced by Wnt signaling or PTH treatment. However, it is still unclear whether lactate, the end product of aerobic glycolysis, plays any role in osteoblast differentiation. Herein we report that in cultures of osteoblast-lineage cells, lactate promoted alkaline phosphatase-positive cell formation, increased the activity of alkaline phosphatase, and induced the expression of osteocalcin. This osteoblast differentiation-inducing effect of lactate can be inhibited by blocking its entry into cells with MCT1 siRNA or inhibitors, and by interfering with its metabolism by using specific siRNAs for LDHB and PDH. Moreover, lactate stabilized HIF1α expression and inhibited HIF1α activity, with BAY87-2243 lowering the osteoblast differentiation-inducing effect of lactate. Thus, these findings reveal an unrecognized role for aerobic glycolysis in osteoblast differentiation via its end product, lactate. Copyright © 2017 Elsevier B.V. All rights reserved.

Insulin-like growth factor-1 suppresses the Myostatin signaling pathway during myogenic differentiation

International Nuclear Information System (INIS)

Retamales, A.; Zuloaga, R.; Valenzuela, C.A.; Gallardo-Escarate, C.; Molina, A.; Valdés, J.A.

2015-01-01

Myogenic differentiation is a complex and well-coordinated process for generating mature skeletal muscle fibers. This event is autocrine/paracrine regulated by growth factors, principally Myostatin (MSTN) and Insulin-like Growth Factor-1 (IGF-1). Myostatin, a member of the transforming growth factor-β superfamily, is a negative regulator of skeletal muscle growth in vertebrates that exerts its inhibitory function by activating Smad transcription factors. In contrast, IGF-1 promotes the differentiation of skeletal myoblasts by activating the PI3K/Akt signaling pathway. This study reports on a novel functional crosstalk between the IGF-1 and MSTN signaling pathways, as mediated through interaction between PI3K/Akt and Smad3. Stimulation of skeletal myoblasts with MSTN resulted in a transient increase in the pSmad3:Smad3 ratio and Smad-dependent transcription. Moreover, MSTN inhibited myod gene expression and myoblast fusion in an Activin receptor-like kinase/Smad3-dependent manner. Preincubation of skeletal myoblasts with IGF-1 blocked MSTN-induced Smad3 activation, promoting myod expression and myoblast differentiation. This inhibitory effect of IGF-1 on the MSTN signaling pathway was dependent on IGF-1 receptor, PI3K, and Akt activities. Finally, immunoprecipitation assay analysis determined that IGF-1 pretreatment increased Akt and Smad3 interaction. These results demonstrate that the IGF-1/PI3K/Akt pathway may inhibit MSTN signaling during myoblast differentiation, providing new insight to existing knowledge on the complex crosstalk between both growth factors. - Highlights: • IGF-1 inhibits Myostatin canonical signaling pathway through IGF-1R/PI3K/Akt pathway. • IGF-1 promotes myoblast differentiation through a direct blocking of Myostatin signaling pathway. • IGF-1 induces the interaction of Akt with Smad3 in skeletal myoblast

Insulin-like growth factor-1 suppresses the Myostatin signaling pathway during myogenic differentiation

Energy Technology Data Exchange (ETDEWEB)

Retamales, A.; Zuloaga, R.; Valenzuela, C.A. [Laboratorio de Biotecnología Molecular, Facultad de Ciencias Biológicas, Universidad Andrés Bello, Santiago (Chile); Gallardo-Escarate, C. [Laboratory of Biotechnology and Aquatic Genomics, Universidad de Concepción, Concepción (Chile); Interdisciplinary Center for Aquaculture Research (INCAR), P.O. Box 160-C, Concepción (Chile); Molina, A. [Laboratorio de Biotecnología Molecular, Facultad de Ciencias Biológicas, Universidad Andrés Bello, Santiago (Chile); Interdisciplinary Center for Aquaculture Research (INCAR), P.O. Box 160-C, Concepción (Chile); Valdés, J.A., E-mail: jvaldes@unab.cl [Laboratorio de Biotecnología Molecular, Facultad de Ciencias Biológicas, Universidad Andrés Bello, Santiago (Chile); Interdisciplinary Center for Aquaculture Research (INCAR), P.O. Box 160-C, Concepción (Chile)

2015-08-21

Myogenic differentiation is a complex and well-coordinated process for generating mature skeletal muscle fibers. This event is autocrine/paracrine regulated by growth factors, principally Myostatin (MSTN) and Insulin-like Growth Factor-1 (IGF-1). Myostatin, a member of the transforming growth factor-β superfamily, is a negative regulator of skeletal muscle growth in vertebrates that exerts its inhibitory function by activating Smad transcription factors. In contrast, IGF-1 promotes the differentiation of skeletal myoblasts by activating the PI3K/Akt signaling pathway. This study reports on a novel functional crosstalk between the IGF-1 and MSTN signaling pathways, as mediated through interaction between PI3K/Akt and Smad3. Stimulation of skeletal myoblasts with MSTN resulted in a transient increase in the pSmad3:Smad3 ratio and Smad-dependent transcription. Moreover, MSTN inhibited myod gene expression and myoblast fusion in an Activin receptor-like kinase/Smad3-dependent manner. Preincubation of skeletal myoblasts with IGF-1 blocked MSTN-induced Smad3 activation, promoting myod expression and myoblast differentiation. This inhibitory effect of IGF-1 on the MSTN signaling pathway was dependent on IGF-1 receptor, PI3K, and Akt activities. Finally, immunoprecipitation assay analysis determined that IGF-1 pretreatment increased Akt and Smad3 interaction. These results demonstrate that the IGF-1/PI3K/Akt pathway may inhibit MSTN signaling during myoblast differentiation, providing new insight to existing knowledge on the complex crosstalk between both growth factors. - Highlights: • IGF-1 inhibits Myostatin canonical signaling pathway through IGF-1R/PI3K/Akt pathway. • IGF-1 promotes myoblast differentiation through a direct blocking of Myostatin signaling pathway. • IGF-1 induces the interaction of Akt with Smad3 in skeletal myoblast.

RSPO1/β-catenin signaling pathway regulates oogonia differentiation and entry into meiosis in the mouse fetal ovary.

Directory of Open Access Journals (Sweden)

Anne-Amandine Chassot

Full Text Available Differentiation of germ cells into male gonocytes or female oocytes is a central event in sexual reproduction. Proliferation and differentiation of fetal germ cells depend on the sex of the embryo. In male mouse embryos, germ cell proliferation is regulated by the RNA helicase Mouse Vasa homolog gene and factors synthesized by the somatic Sertoli cells promote gonocyte differentiation. In the female, ovarian differentiation requires activation of the WNT/β-catenin signaling pathway in the somatic cells by the secreted protein RSPO1. Using mouse models, we now show that Rspo1 also activates the WNT/β-catenin signaling pathway in germ cells. In XX Rspo1(-/- gonads, germ cell proliferation, expression of the early meiotic marker Stra8, and entry into meiosis are all impaired. In these gonads, impaired entry into meiosis and germ cell sex reversal occur prior to detectable Sertoli cell differentiation, suggesting that β-catenin signaling acts within the germ cells to promote oogonial differentiation and entry into meiosis. Our results demonstrate that RSPO1/β-catenin signaling is involved in meiosis in fetal germ cells and contributes to the cellular decision of germ cells to differentiate into oocyte or sperm.

Genome-wide analysis of promoter architecture in Drosophila melanogaster

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Hoskins, Roger A.; Landolin, Jane M.; Brown, James B.; Sandler, Jeremy E.; Takahashi, Hazuki; Lassmann, Timo; Yu, Charles; Booth, Benjamin W.; Zhang, Dayu; Wan, Kenneth H.; Yang, Li; Boley, Nathan; Andrews, Justen; Kaufman, Thomas C.; Graveley, Brenton R.; Bickel, Peter J.; Carninci, Piero; Carlson, Joseph W.; Celniker, Susan E.

2010-10-20

Core promoters are critical regions for gene regulation in higher eukaryotes. However, the boundaries of promoter regions, the relative rates of initiation at the transcription start sites (TSSs) distributed within them, and the functional significance of promoter architecture remain poorly understood. We produced a high-resolution map of promoters active in the Drosophila melanogaster embryo by integrating data from three independent and complementary methods: 21 million cap analysis of gene expression (CAGE) tags, 1.2 million RNA ligase mediated rapid amplification of cDNA ends (RLMRACE) reads, and 50,000 cap-trapped expressed sequence tags (ESTs). We defined 12,454 promoters of 8037 genes. Our analysis indicates that, due to non-promoter-associated RNA background signal, previous studies have likely overestimated the number of promoter-associated CAGE clusters by fivefold. We show that TSS distributions form a complex continuum of shapes, and that promoters active in the embryo and adult have highly similar shapes in 95% of cases. This suggests that these distributions are generally determined by static elements such as local DNA sequence and are not modulated by dynamic signals such as histone modifications. Transcription factor binding motifs are differentially enriched as a function of promoter shape, and peaked promoter shape is correlated with both temporal and spatial regulation of gene expression. Our results contribute to the emerging view that core promoters are functionally diverse and control patterning of gene expression in Drosophila and mammals.

The Transcription Factor c-Maf Promotes the Differentiation of Follicular Helper T Cells

Directory of Open Access Journals (Sweden)

Fabienne Andris

2017-04-01

Full Text Available Follicular helper T cells (Tfh have been identified as the primary cell subpopulation regulating B cell responses in germinal centers, thus supporting high-affinity antibody production. Among the transcription factors orchestrating Tfh cell differentiation and function, the role played by the proto-oncogene c-Maf remains poorly characterized. We report herein that selective loss of c-Maf expression in the T cell compartment results in defective development of Tfh cells in response to both antigen/adjuvant vaccinations and commensal intestinal bacteria. Accordingly, c-Maf expression in T cells was essential for the development and high-affinity antibody secretion in vaccinated animals. c-Maf was expressed early, concomitantly to BCL6, in Tfh cell precursors and found to regulate Tfh fate in a cell-autonomous fashion. Altogether, our findings reveal a novel, non-redundant, function for c-Maf in the differentiation of Tfh cells and the regulation of humoral immune responses to T-cell-dependent antigens.

Nukbone® promotes proliferation and osteoblastic differentiation of mesenchymal stem cells from human amniotic membrane

Energy Technology Data Exchange (ETDEWEB)

Rodríguez-Fuentes, Nayeli; Rodríguez-Hernández, Ana G. [Depto. Microbiología y Parasitología, Facultad de Medicina, Universidad Nacional Autónoma de México (UNAM), Mexico City 04510 (Mexico); Enríquez-Jiménez, Juana [Depto. Biología de la Reproducción, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán (INCMNSZ), México City 14000 (Mexico); Alcántara-Quintana, Luz E. [Subd. de Investigación, Centro Nacional de la Transfusión Sanguínea, Secretaria de Salud, Mexico City 07370 (Mexico); Fuentes-Mera, Lizeth [Depto. Biología Molecular e Histocompatibilidad, Hospital General “Dr. Manuel Gea González”, México City 4800 (Mexico); Piña-Barba, María C. [Depto. Materiales Metálicos y Cerámicos, Instituto de Investigaciones en Materiales, Universidad Nacional Autónoma de México (UNAM), México City 04510 (Mexico); Zepeda-Rodríguez, Armando [Depto. Biología Celular y Tisular, Facultad de Medicina, Universidad Nacional Autónoma de México (UNAM), México City 04510 (Mexico); and others

2013-05-10

Highlights: •Nukbone showed to be a good scaffold for adhesion, proliferation and differentiation of stem cells. •Nukbone induced osteoblastic differentiation of human mesenchymal stem cells. •Results showed that Nukbone offer an excellent option for bone tissue regeneration due to properties. -- Abstract: Bovine bone matrix Nukbone® (NKB) is an osseous tissue-engineering biomaterial that retains its mineral and organic phases and its natural bone topography and has been used as a xenoimplant for bone regeneration in clinics. There are not studies regarding its influence of the NKB in the behavior of cells during the repairing processes. The aim of this research is to demonstrate that NKB has an osteoinductive effect in human mesenchymal stem cells from amniotic membrane (AM-hMSCs). Results indicated that NKB favors the AM-hMSCs adhesion and proliferation up to 7 days in culture as shown by the scanning electron microscopy and proliferation measures using an alamarBlue assay. Furthermore, as demonstrated by reverse transcriptase polymerase chain reaction, it was detected that two gene expression markers of osteoblastic differentiation: the core binding factor and osteocalcin were higher for AM-hMSCs co-cultured with NKB in comparison with cultivated cells in absence of the biomaterial. As the results indicate, NKB possess the capability for inducing successfully the osteoblastic differentiation of AM-hMSC, so that, NKB is an excellent xenoimplant option for repairing bone tissue defects.

Nukbone® promotes proliferation and osteoblastic differentiation of mesenchymal stem cells from human amniotic membrane

International Nuclear Information System (INIS)

Rodríguez-Fuentes, Nayeli; Rodríguez-Hernández, Ana G.; Enríquez-Jiménez, Juana; Alcántara-Quintana, Luz E.; Fuentes-Mera, Lizeth; Piña-Barba, María C.; Zepeda-Rodríguez, Armando

2013-01-01

Highlights: •Nukbone showed to be a good scaffold for adhesion, proliferation and differentiation of stem cells. •Nukbone induced osteoblastic differentiation of human mesenchymal stem cells. •Results showed that Nukbone offer an excellent option for bone tissue regeneration due to properties. -- Abstract: Bovine bone matrix Nukbone® (NKB) is an osseous tissue-engineering biomaterial that retains its mineral and organic phases and its natural bone topography and has been used as a xenoimplant for bone regeneration in clinics. There are not studies regarding its influence of the NKB in the behavior of cells during the repairing processes. The aim of this research is to demonstrate that NKB has an osteoinductive effect in human mesenchymal stem cells from amniotic membrane (AM-hMSCs). Results indicated that NKB favors the AM-hMSCs adhesion and proliferation up to 7 days in culture as shown by the scanning electron microscopy and proliferation measures using an alamarBlue assay. Furthermore, as demonstrated by reverse transcriptase polymerase chain reaction, it was detected that two gene expression markers of osteoblastic differentiation: the core binding factor and osteocalcin were higher for AM-hMSCs co-cultured with NKB in comparison with cultivated cells in absence of the biomaterial. As the results indicate, NKB possess the capability for inducing successfully the osteoblastic differentiation of AM-hMSC, so that, NKB is an excellent xenoimplant option for repairing bone tissue defects

Effect of resveratrol on proliferation and differentiation of embryonic cardiomyoblasts

International Nuclear Information System (INIS)

Leong, C.-W.; Wong, C.H.; Lao, S.-C.; Leong, Emilia Conceicao; Lao, Iok Fong; Law, Patrick Tik Wan; Fung, Kwok Pui; Tsang, Kam Sze; Waye, Mary Miu-Yee; Tsui, Stephen Kwok-Wing; Wang Yitao; Lee, Simon Ming-Yuen

2007-01-01

Resveratrol (trans-3,5,4'-trihydroxystilbene), a polyphenolic compound found largely in the skins of red grapes, has been used as a nutritional supplement or an investigational new drug for prevention of cardiovascular diseases. Previous reports showed that resveratrol had a protective effect against oxidative agent-induced cell injury. Our studies indicate that resveratrol plays a role in the differentiation of cardiomyoblasts. The cardiomyoblast cell line, H9c2, was exposed to 30-120 μM resveratrol for up to 5 days. Resveratrol inhibits cardiomyoblast proliferation without causing cells injury. Moreover, resveratrol treatment modulated the differentiation of morphological characteristics including elongation and cell fusion in cardiomyoblasts. Proliferation and differentiation of H9c2 cells were further revealed by measurement of the mRNA expression of a cell cycle marker (CDK2), a differentiation marker (myogenin), and a contractile apparatus protein (MLC-2). Gene expression analysis revealed that resveratrol promoted entry into cell cycle arrest but extended the myogenic differentiation progress. These results have implications for the role of resveratrol in modulating cell cycle control and differentiation in cardiomyoblasts

Regulation of T Cell Differentiation and Function by EZH2

Science.gov (United States)

Karantanos, Theodoros; Christofides, Anthos; Bardhan, Kankana; Li, Lequn; Boussiotis, Vassiliki A.

2016-01-01

The enhancer of zeste homolog 2 (EZH2), one of the polycomb-group proteins, is the catalytic subunit of Polycomb-repressive complex 2 (PRC2) and induces the trimethylation of the histone H3 lysine 27 (H3K27me3) promoting epigenetic gene silencing. EZH2 contains a SET domain promoting the methyltransferase activity, while the three other protein components of PRC2, namely EED, SUZ12, and RpAp46/48, induce compaction of the chromatin permitting EZH2 enzymatic activity. Numerous studies highlight the role of this evolutionary conserved protein as a master regulator of differentiation in humans involved in the repression of the homeotic gene and the inactivation of X-chromosome. Through its effects in the epigenetic regulation of critical genes, EZH2 has been strongly linked to cell cycle progression, stem cell pluripotency, and cancer biology, being currently at the cutting edge of research. Most recently, EZH2 has been associated with hematopoietic stem cell proliferation and differentiation, thymopoiesis and lymphopoiesis. Several studies have evaluated the role of EZH2 in the regulation of T cell differentiation and plasticity as well as its implications in the development of autoimmune diseases and graft-versus-host disease (GVHD). The aim of this review is to summarize the current knowledge regarding the role of EZH2 in the regulation of the differentiation and function of T cells focusing on possible applications in various immune-mediated conditions, including autoimmune disorders and GVHD. PMID:27199994

Role of alpha- and beta-adrenergic receptors in cardiomyocyte differentiation from murine-induced pluripotent stem cells.

Science.gov (United States)

Li, Xiao-Li; Zeng, Di; Chen, Yan; Ding, Lu; Li, Wen-Ju; Wei, Ting; Ou, Dong-Bo; Yan, Song; Wang, Bin; Zheng, Qiang-Sun

2017-02-01

Induced pluripotent stem cell (iPSC)-derived cardiomyocytes are a promising source of cells for regenerative heart disease therapies, but progress towards their use has been limited by their low differentiation efficiency and high cellular heterogeneity. Previous studies have demonstrated expression of adrenergic receptors (ARs) in stem cells after differentiation; however, roles of ARs in fate specification of stem cells, particularly in cardiomyocyte differentiation and development, have not been characterized. Murine-induced pluripotent stem cells (miPSCs) were cultured in hanging drops to form embryoid bodies, cells of which were then differentiated into cardiomyocytes. To determine whether ARs regulated miPSC differentiation into cardiac lineages, effects of the AR agonist, epinephrine (EPI), on miPSC differentiation and underlying signalling mechanisms, were evaluated. Treatment with EPI, robustly enhanced miPSC cardiac differentiation, as indicated by increased expression levels of cardiac-specific markers, GATA4, Nkx2.5 and Tnnt2. Although β-AR signalling is the foremost signalling pathway in cardiomyocytes, EPI-enhanced cardiac differentiation depended more on α-AR signalling than β-AR signalling. In addition, selective activation of α 1 -AR signalling with specific agonists induced vigorous cardiomyocyte differentiation, whereas selective activation of α 2 - or β-AR signalling induced no or less differentiation, respectively. EPI- and α 1 -AR-dependent cardiomyocyte differentiation from miPSCs occurred through specific promotion of CPC proliferation via the MEK-ERK1/2 pathway and regulation of miPS cell-cycle progression. These results demonstrate that activation of ARs, particularly of α 1 -ARs, promoted miPSC differentiation into cardiac lineages via MEK-ERK1/2 signalling. © 2016 John Wiley & Sons Ltd.

Differential response of potato toward inoculation with taxonomically diverse plant growth promoting Rhizobacteria

NARCIS (Netherlands)

Naqqash, Tahir; Hameed, Sohail; Imran, Asma; Hanif, Muhammad Kashif; Majeed, Afshan; van Elsas, Jan Dirk

2016-01-01

Rhizosphere engineering with beneficial plant growth promoting bacteria offers great promise for sustainable crop yield. Potato is an important food commodity that needs large inputs of nitrogen and phosphorus fertilizers. To overcome high fertilizer demand (especially nitrogen), five bacteria,

MicroRNA-1 Regulates the Differentiation of Adipose-Derived Stem Cells into Cardiomyocyte-Like Cells

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Can Chen

2018-01-01

Full Text Available Stem cell transplantation is one of most valuable methods in the treatment of myocardial infarction, and adipose-derived stem cells (ASCs are becoming a hot topic in medical research. Previous studies have shown that ASCs can be differentiated into cardiomyocyte-like cells, but the efficiency and survival rates are low. We investigated the role and mechanism of microRNA-1 (miR-1 in the differentiation of ASCs into cardiomyocyte-like cells. ASCs and cardiomyocytes were isolated from neonatal rats. We constructed lentivirus for overexpressing miR-1 and used DAPT, an antagonist of the Notch1 pathway, for in vitro analyses. We performed cocultures with ASCs and cardiomyocytes. The differentiation efficiency of ASCs was detected by cell-specific surface antigens. Our results showed that miR-1 can promote the expression of Notch1 and reduce the expression of Hes1, a Notch pathway factor, and overexpression of miR-1 can promote the differentiation of ASCs into cardiomyocyte-like cells, which may occur by regulating Notch1 and Hes1.

The expression of VE-cadherin in breast cancer cells modulates cell dynamics as a function of tumor differentiation and promotes tumor-endothelial cell interactions.

Science.gov (United States)

Rezaei, Maryam; Cao, Jiahui; Friedrich, Katrin; Kemper, Björn; Brendel, Oliver; Grosser, Marianne; Adrian, Manuela; Baretton, Gustavo; Breier, Georg; Schnittler, Hans-Joachim

2018-01-01

The cadherin switch has profound consequences on cancer invasion and metastasis. The endothelial-specific vascular endothelial cadherin (VE-cadherin) has been demonstrated in diverse cancer types including breast cancer and is supposed to modulate tumor progression and metastasis, but underlying mechanisms need to be better understood. First, we evaluated VE-cadherin expression by tissue microarray in 392 cases of breast cancer tumors and found a diverse expression and distribution of VE-cadherin. Experimental expression of fluorescence-tagged VE-cadherin (VE-EGFP) in undifferentiated, fibroblastoid and E-cadherin-negative MDA-231 (MDA-VE-EGFP) as well as in differentiated E-cadherin-positive MCF-7 human breast cancer cell lines (MCF-VE-EGFP), respectively, displayed differentiation-dependent functional differences. VE-EGFP expression reversed the fibroblastoid MDA-231 cells to an epithelial-like phenotype accompanied by increased β-catenin expression, actin and vimentin remodeling, increased cell spreading and barrier function and a reduced migration ability due to formation of VE-cadherin-mediated cell junctions. The effects were largely absent in both MDA-VE-EGFP and in control MCF-EGFP cell lines. However, MCF-7 cells displayed a VE-cadherin-independent planar cell polarity and directed cell migration that both developed in MDA-231 only after VE-EGFP expression. Furthermore, VE-cadherin expression had no effect on tumor cell proliferation in monocultures while co-culturing with endothelial cells enhanced tumor cell proliferation due to integration of the tumor cells into monolayer where they form VE-cadherin-mediated cell contacts with the endothelium. We propose an interactive VE-cadherin-based crosstalk that might activate proliferation-promoting signals. Together, our study shows a VE-cadherin-mediated cell dynamics and an endothelial-dependent proliferation in a differentiation-dependent manner.

Regulatory T Cells in Skin Facilitate Epithelial Stem Cell Differentiation.

Science.gov (United States)

Ali, Niwa; Zirak, Bahar; Rodriguez, Robert Sanchez; Pauli, Mariela L; Truong, Hong-An; Lai, Kevin; Ahn, Richard; Corbin, Kaitlin; Lowe, Margaret M; Scharschmidt, Tiffany C; Taravati, Keyon; Tan, Madeleine R; Ricardo-Gonzalez, Roberto R; Nosbaum, Audrey; Bertolini, Marta; Liao, Wilson; Nestle, Frank O; Paus, Ralf; Cotsarelis, George; Abbas, Abul K; Rosenblum, Michael D

2017-06-01

The maintenance of tissue homeostasis is critically dependent on the function of tissue-resident immune cells and the differentiation capacity of tissue-resident stem cells (SCs). How immune cells influence the function of SCs is largely unknown. Regulatory T cells (Tregs) in skin preferentially localize to hair follicles (HFs), which house a major subset of skin SCs (HFSCs). Here, we mechanistically dissect the role of Tregs in HF and HFSC biology. Lineage-specific cell depletion revealed that Tregs promote HF regeneration by augmenting HFSC proliferation and differentiation. Transcriptional and phenotypic profiling of T regs and HFSCs revealed that skin-resident Tregs preferentially express high levels of the Notch ligand family member, Jagged 1 (Jag1). Expression of Jag1 on Tregs facilitated HFSC function and efficient HF regeneration. Taken together, our work demonstrates that Tregs in skin play a major role in HF biology by promoting the function of HFSCs. Copyright © 2017 Elsevier Inc. All rights reserved.

DNA-damage-induced differentiation of leukaemic cells as an anti-cancer barrier.

Science.gov (United States)

Santos, Margarida A; Faryabi, Robert B; Ergen, Aysegul V; Day, Amanda M; Malhowski, Amy; Canela, Andres; Onozawa, Masahiro; Lee, Ji-Eun; Callen, Elsa; Gutierrez-Martinez, Paula; Chen, Hua-Tang; Wong, Nancy; Finkel, Nadia; Deshpande, Aniruddha; Sharrow, Susan; Rossi, Derrick J; Ito, Keisuke; Ge, Kai; Aplan, Peter D; Armstrong, Scott A; Nussenzweig, André

2014-10-02

Self-renewal is the hallmark feature both of normal stem cells and cancer stem cells. Since the regenerative capacity of normal haematopoietic stem cells is limited by the accumulation of reactive oxygen species and DNA double-strand breaks, we speculated that DNA damage might also constrain leukaemic self-renewal and malignant haematopoiesis. Here we show that the histone methyl-transferase MLL4, a suppressor of B-cell lymphoma, is required for stem-cell activity and an aggressive form of acute myeloid leukaemia harbouring the MLL-AF9 oncogene. Deletion of MLL4 enhances myelopoiesis and myeloid differentiation of leukaemic blasts, which protects mice from death related to acute myeloid leukaemia. MLL4 exerts its function by regulating transcriptional programs associated with the antioxidant response. Addition of reactive oxygen species scavengers or ectopic expression of FOXO3 protects MLL4(-/-) MLL-AF9 cells from DNA damage and inhibits myeloid maturation. Similar to MLL4 deficiency, loss of ATM or BRCA1 sensitizes transformed cells to differentiation, suggesting that myeloid differentiation is promoted by loss of genome integrity. Indeed, we show that restriction-enzyme-induced double-strand breaks are sufficient to induce differentiation of MLL-AF9 blasts, which requires cyclin-dependent kinase inhibitor p21(Cip1) (Cdkn1a) activity. In summary, we have uncovered an unexpected tumour-promoting role of genome guardians in enforcing the oncogene-induced differentiation blockade in acute myeloid leukaemia.

Lithium doped calcium phosphate cement maintains physical mechanical properties and promotes osteoblast proliferation and differentiation.

Science.gov (United States)

Li, Li; Wang, Renchong; Li, Baichuan; Liang, Wei; Pan, Haobo; Cui, Xu; Tang, Jingli; Li, Bing

2017-07-01

Calcium phosphate cement (CPC) has been widely used in bone tissue repairing due to its physical mechanical properties and biocompatibility. Addition of trace element to CPC has shown promising evidence to improve the physical properties and biological activities of CPC. Lithium (Li) has effect on osteoblast proliferation and differentiation. In this study, we incorporated Li to CPC and examined the physical properties of Li/CPC and its effect on osteoblast proliferation and differentiation. We found that Li doped CPC maintained similar setting time, pore size distribution, compressive strength, composition, and morphology as CPC without Li. Additionally, Li doped CPC improved osteoblast proliferation and differentiation significantly compared to CPC without Li. To our knowledge, our results, for the first time, show that Li doped CPC has beneficial effect on osteoblast in cell culture while keeps the excellent physical-mechanical properties of CPC. This study will lead to potential application of Li doped CPC in bone tissue engineering. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 944-952, 2017. © 2016 Wiley Periodicals, Inc.

Upstream-Downstream Joint Carbon Reduction Strategies Based on Low-Carbon Promotion

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Xiqiang Xia

2018-06-01

Full Text Available A differential game model is established to analyze the impact of emissions reduction efforts and low-carbon product promotion on the reduction strategies of low-carbon product manufacturers (subsequently referred to as manufacturers and the retailers of such products in a dynamic environment. Based on this model, changes in emissions reduction efforts and promotional efforts are comparatively analyzed under three scenarios (retailers bearing the promotional cost, manufacturers bearing the promotional cost, and centralized decision-making. The results are as follows: (1 the trajectory of carbon emissions reduction per product unit is the highest when the supply chain is under centralized decision-making, followed by when manufacturers bear the promotional cost, and lastly when retailers bear the cost; (2 when manufacturers bear the promotional cost, the market demand, emissions reduction effort, and promotional effort are higher, although the unit retail price is higher than when retailers bear the promotional cost; and (3 under centralized decision-making, the unit retail price is the lowest; however, sales volume, the emissions reduction effort, and the promotional effort are all higher than those in the other scenarios.

Molecular Mechanisms of Mouse Skin Tumor Promotion

International Nuclear Information System (INIS)

Rundhaug, Joyce E.; Fischer, Susan M.

2010-01-01

Multiple molecular mechanisms are involved in the promotion of skin carcinogenesis. Induction of sustained proliferation and epidermal hyperplasia by direct activation of mitotic signaling pathways or indirectly in response to chronic wounding and/or inflammation, or due to a block in terminal differentiation or resistance to apoptosis is necessary to allow clonal expansion of initiated cells with DNA mutations to form skin tumors. The mitotic pathways include activation of epidermal growth factor receptor and Ras/Raf/mitogen-activated protein kinase signaling. Chronic inflammation results in inflammatory cell secretion of growth factors and cytokines such as tumor necrosis factor-α and interleukins, as well as production of reactive oxygen species, all of which can stimulate proliferation. Persistent activation of these pathways leads to tumor promotion

Moderate Increase of Indoxyl Sulfate Promotes Monocyte Transition into Profibrotic Macrophages.

Directory of Open Access Journals (Sweden)

Chiara Barisione

Full Text Available The uremic toxin Indoxyl-3-sulphate (IS, a ligand of Aryl hydrocarbon Receptor (AhR, raises in blood during early renal dysfunction as a consequence of tubular damage, which may be present even when eGFR is normal or only moderately reduced, and promotes cardiovascular damage and monocyte-macrophage activation. We previously found that patients with abdominal aortic aneurysms (AAAs have higher CD14+CD16+ monocyte frequency and prevalence of moderate chronic kidney disease (CKD than age-matched control subjects. Here we aimed to evaluate the IS levels in plasma from AAA patients and to investigate in vitro the effects of IS concentrations corresponding to mild-to-moderate CKD on monocyte polarization and macrophage differentiation.Free IS plasma levels, monocyte subsets and laboratory parameters were evaluated on blood from AAA patients and eGFR-matched controls. THP-1 monocytes, treated with IS 1, 10, 20 μM were evaluated for CD163 expression, AhR signaling and then induced to differentiate into macrophages by PMA. Their phenotype was evaluated both at the stage of semi-differentiated and fully differentiated macrophages. AAA and control sera were similarly used to treat THP-1 monocytes and the resulting macrophage phenotype was analyzed.IS plasma concentration correlated positively with CD14+CD16+ monocytes and was increased in AAA patients. In THP-1 cells, IS promoted CD163 expression and transition to macrophages with hallmarks of classical (IL-6, CCL2, COX2 and alternative phenotype (IL-10, PPARγ, TGF-β, TIMP-1, via AhR/Nrf2 activation. Analogously, AAA sera induced differentiation of macrophages with enhanced IL-6, MCP1, TGF-β, PPARγ and TIMP-1 expression.IS skews monocyte differentiation toward low-inflammatory, profibrotic macrophages and may contribute to sustain chronic inflammation and maladaptive vascular remodeling.

Hyperglycemia Promotes Schwann Cell De-differentiation and De-myelination via Sorbitol Accumulation and Igf1 Protein Down-regulation*

Science.gov (United States)

Hao, Wu; Tashiro, Syoichi; Hasegawa, Tomoka; Sato, Yuiko; Kobayashi, Tami; Tando, Toshimi; Katsuyama, Eri; Fujie, Atsuhiro; Watanabe, Ryuichi; Morita, Mayu; Miyamoto, Kana; Morioka, Hideo; Nakamura, Masaya; Matsumoto, Morio; Amizuka, Norio; Toyama, Yoshiaki; Miyamoto, Takeshi

2015-01-01

Diabetes mellitus (DM) is frequently accompanied by complications, such as peripheral nerve neuropathy. Schwann cells play a pivotal role in regulating peripheral nerve function and conduction velocity; however, changes in Schwann cell differentiation status in DM are not fully understood. Here, we report that Schwann cells de-differentiate into immature cells under hyperglycemic conditions as a result of sorbitol accumulation and decreased Igf1 expression in those cells. We found that de-differentiated Schwann cells could be re-differentiated in vitro into mature cells by treatment with an aldose reductase inhibitor, to reduce sorbitol levels, or with vitamin D3, to elevate Igf1 expression. In vivo DM models exhibited significantly reduced nerve function and conduction, Schwann cell de-differentiation, peripheral nerve de-myelination, and all conditions were significantly rescued by aldose reductase inhibitor or vitamin D3 administration. These findings reveal mechanisms underlying pathological changes in Schwann cells seen in DM and suggest ways to treat neurological conditions associated with this condition. PMID:25998127

CD4+CD25+ regulatory T cells control CD8+ T-cell effector differentiation by modulating IL-2 homeostasis

Science.gov (United States)

McNally, Alice; Hill, Geoffrey R.; Sparwasser, Tim; Thomas, Ranjeny; Steptoe, Raymond J.

2011-01-01

CD4+CD25+ regulatory T cells (Treg) play a crucial role in the regulation of immune responses. Although many mechanisms of Treg suppression in vitro have been described, the mechanisms by which Treg modulate CD8+ T cell differentiation and effector function in vivo are more poorly defined. It has been proposed, in many instances, that modulation of cytokine homeostasis could be an important mechanism by which Treg regulate adaptive immunity; however, direct experimental evidence is sparse. Here we demonstrate that CD4+CD25+ Treg, by critically regulating IL-2 homeostasis, modulate CD8+ T-cell effector differentiation. Expansion and effector differentiation of CD8+ T cells is promoted by autocrine IL-2 but, by competing for IL-2, Treg limit CD8+ effector differentiation. Furthermore, a regulatory loop exists between Treg and CD8+ effector T cells, where IL-2 produced during CD8+ T-cell effector differentiation promotes Treg expansion. PMID:21502514

Telomerase activity promotes osteoblast differentiation by modulating IGF-signaling pathway

DEFF Research Database (Denmark)

Saeed, Hamid; Qiu, Weimin; Li, Chen

2015-01-01

-regulation of several components of insulin-like growth factor (IGF) signaling. Specifically, a significant increase in IGF-induced AKT phosphorylation and alkaline phosphatase (ALP) activity were observed in hMSC-TERT. Enhanced ALP activity was reduced in presence of IGF1 receptor inhibitor: picropodophyllin....... In addition, telomerase deficiency caused significant reduction in IGF signaling proteins in osteoblastic cells cultured from telomerase deficient mice (Terc (-/-)). The low bone mass exhibited by Terc (-/-) mice was associated with significant reduction in serum levels of IGF1 and IGFBP3 as well as reduced...... skeletal mRNA expression of Igf1, Igf2, Igf2r, Igfbp5 and Igfbp6. IGF1-induced osteoblast differentiation was also impaired in Terc (-/-) MSC. In conclusion, our data demonstrate that impaired IGF/AKT signaling contributes to the observed decreased bone mass and bone formation exhibited by telomerase...

Somatic stem cell differentiation is regulated by PI3K/Tor signaling in response to local cues.

Science.gov (United States)

Amoyel, Marc; Hillion, Kenzo-Hugo; Margolis, Shally R; Bach, Erika A

2016-11-01

Stem cells reside in niches that provide signals to maintain self-renewal, and differentiation is viewed as a passive process that depends on loss of access to these signals. Here, we demonstrate that the differentiation of somatic cyst stem cells (CySCs) in the Drosophila testis is actively promoted by PI3K/Tor signaling, as CySCs lacking PI3K/Tor activity cannot differentiate properly. We find that an insulin peptide produced by somatic cells immediately outside of the stem cell niche acts locally to promote somatic differentiation through Insulin-like receptor (InR) activation. These results indicate that there is a local 'differentiation' niche that upregulates PI3K/Tor signaling in the early daughters of CySCs. Finally, we demonstrate that CySCs secrete the Dilp-binding protein ImpL2, the Drosophila homolog of IGFBP7, into the stem cell niche, which blocks InR activation in CySCs. Thus, we show that somatic cell differentiation is controlled by PI3K/Tor signaling downstream of InR and that the local production of positive and negative InR signals regulates the differentiation niche. These results support a model in which leaving the stem cell niche and initiating differentiation are actively induced by signaling. © 2016. Published by The Company of Biologists Ltd.

MicroRNA-138 regulates osteogenic differentiation of human stromal (mesenchymal) stem cells in vivo

DEFF Research Database (Denmark)

Eskildsen, Tilde; Taipaleenmäki, Hanna; Stenvang, Jan

2011-01-01

Elucidating the molecular mechanisms that regulate human stromal (mesenchymal) stem cell (hMSC) differentiation into osteogenic lineage is important for the development of anabolic therapies for treatment of osteoporosis. MicroRNAs (miRNAs) are short, noncoding RNAs that act as key regulators......-regulated during osteoblast differentiation of hMSCs. Overexpression of miR-138 inhibited osteoblast differentiation of hMSCs in vitro, whereas inhibition of miR-138 function by antimiR-138 promoted expression of osteoblast-specific genes, alkaline phosphatase (ALP) activity, and matrix mineralization. Furthermore...

Tracking plasma cell differentiation and survival.

Science.gov (United States)

Roth, Katrin; Oehme, Laura; Zehentmeier, Sandra; Zhang, Yang; Niesner, Raluca; Hauser, Anja E

2014-01-01

Plasma cells play a crucial role for the humoral immune response as they represent the body's factories for antibody production. The differentiation from a B cell into a plasma cell is controlled by a complex transcriptional network and happens within secondary lymphoid organs. Based on their lifetime, two types of antibody secreting cells can be distinguished: Short-lived plasma cells are located in extrafollicular sites of secondary lymphoid organs such as lymph node medullary cords and the splenic red pulp. A fraction of plasmablasts migrate from secondary lymphoid organs to the bone marrow where they can become long-lived plasma cells. Bone marrow plasma cells reside in special microanatomical environments termed survival niches, which provide factors promoting their longevity. Reticular stromal cells producing the chemokine CXCL12, which is known to attract plasmablasts to the bone marrow but also to promote plasma cell survival, play a crucial role in the maintenance of these niches. In addition, hematopoietic cells are contributing to the niches by providing other soluble survival factors. Here, we review the current knowledge on the factors involved in plasma cell differentiation, their localization and migration. We also give an overview on what is known regarding the maintenance of long lived plasma cells in survival niches of the bone marrow. © 2013 International Society for Advancement of Cytometry.

IGF-II Promotes Stemness of Neural Restricted Precursors

Science.gov (United States)

Ziegler, Amber N.; Schneider, Joel S.; Qin, Mei; Tyler, William A.; Pintar, John E.; Fraidenraich, Diego; Wood, Teresa L.; Levison, Steven W.

2016-01-01

Insulin-like growth factor (IGF)-I and IGF-II regulate brain development and growth through the IGF type 1 receptor (IGF-1R). Less appreciated is that IGF-II, but not IGF-I, activates a splice variant of the insulin receptor (IR) known as IR-A. We hypothesized that IGF-II exerts distinct effects from IGF-I on neural stem/progenitor cells (NSPs) via its interaction with IR-A. Immunofluorescence revealed high IGF-II in the medial region of the subventricular zone (SVZ) comprising the neural stem cell niche, with IGF-II mRNA predominant in the adjacent choroid plexus. The IGF-1R and the IR isoforms were differentially expressed with IR-A predominant in the medial SVZ, whereas the IGF-1R was more abundant laterally. Similarly, IR-A was more highly expressed by NSPs, whereas the IGF-1R was more highly expressed by lineage restricted cells. In vitro, IGF-II was more potent in promoting NSP expansion than either IGF-I or standard growth medium. Limiting dilution and differentiation assays revealed that IGF-II was superior to IGF-I in promoting stemness. In vivo, NSPs propagated in IGF-II migrated to and took up residence in periventricular niches while IGF-I-treated NSPs predominantly colonized white matter. Knockdown of IR or IGF-1R using shRNAs supported the conclusion that the IGF-1R promotes progenitor proliferation, whereas the IR is important for self-renewal. Q-PCR revealed that IGF-II increased Oct4, Sox1, and FABP7 mRNA levels in NSPs. Our data support the conclusion that IGF-II promotes the self-renewal of neural stem/progenitors via the IR. By contrast, IGF-1R functions as a mitogenic receptor to increase precursor abundance. PMID:22593020

Brain cytoplasmic RNA 1 suppresses smooth muscle differentiation and vascular development in mice.

Science.gov (United States)

Wang, Yung-Chun; Chuang, Ya-Hui; Shao, Qiang; Chen, Jian-Fu; Chen, Shi-You

2018-04-13

The cardiovascular system develops during the early stages of embryogenesis, and differentiation of smooth muscle cells (SMCs) is essential for that process. SMC differentiation is critically regulated by transforming growth factor (TGF)-β/SMAD family member 3 (SMAD3) signaling, but other regulators may also play a role. For example, long noncoding RNAs (lncRNAs) regulate various cellular activities and events, such as proliferation, differentiation, and apoptosis. However, whether long noncoding RNAs also regulate SMC differentiation remains largely unknown. Here, using the murine cell line C3H10T1/2, we found that brain cytoplasmic RNA 1 (BC1) is an important regulator of SMC differentiation. BC1 overexpression suppressed, whereas BC1 knockdown promoted, TGF-β-induced SMC differentiation, as indicated by altered cell morphology and expression of multiple SMC markers, including smooth muscle α-actin (αSMA), calponin, and smooth muscle 22α (SM22α). BC1 appeared to block SMAD3 activity and inhibit SMC marker gene transcription. Mechanistically, BC1 bound to SMAD3 via RNA SMAD-binding elements (rSBEs) and thus impeded TGF-β-induced SMAD3 translocation to the nucleus. This prevented SMAD3 from binding to SBEs in SMC marker gene promoters, an essential event in SMC marker transcription. In vivo , BC1 overexpression in mouse embryos impaired vascular SMC differentiation, leading to structural defects in the artery wall, such as random breaks in the elastic lamina, abnormal collagen deposition on SM fibers, and disorganized extracellular matrix proteins in the media of the neonatal aorta. Our results suggest that BC1 is a suppressor of SMC differentiation during vascular development. © 2018 by The American Society for Biochemistry and Molecular Biology, Inc.

Social deprivation and exposure to health promotion. A study of the distribution of health promotion resources to schools in England

Directory of Open Access Journals (Sweden)

Reidpath Daniel D

2010-08-01

Full Text Available Abstract Background Area deprivation is a known determinant of health. It is also known that area deprivation is associated with lower impact health promotion. It is less well known, however, whether deprived areas are less responsive to health promotion, or whether they are less exposed. Using data from a national, school-based campaign to promote vaccination against the human papilloma virus (HPV, the relationship between area deprivation and exposure was examined. Methods Taking advantage of a health promotion campaign to provide information to schools about HPV vaccination, a cross sectional study was conducted to examine the relationship between area level, social deprivation, and take-up of (i.e., exposure to available health promotion material. The sample was 4,750 schools across England, including government maintained and independent schools. The relationship between area deprivation and exposure was examined using bi- and multivariate logistic regression. Results It was found that schools in the least deprived quintile had 1.32 times the odds of requesting health promotion materials than schools in the most deprived areas (p = .01. This effect was independent of the school size, the type of school, and the geographic region. Conclusion The relationship between area deprivation and the impact of health promotion may be due, at least in part, to differential levels of exposure. The study was limited in scope, pointing to the need for more research, but also points to potentially important policy implications.