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Sample records for factor-2 enhances proliferation

  1. Chicken stem cell factor enhances primordial germ cell proliferation cooperatively with fibroblast growth factor 2

    PubMed Central

    MIYAHARA, Daichi; OISHI, Isao; MAKINO, Ryuichi; KURUMISAWA, Nozomi; NAKAYA, Ryuma; ONO, Tamao; KAGAMI, Hiroshi; TAGAMI, Takahiro

    2015-01-01

    An in vitro culture system of chicken primordial germ cells (PGCs) has been recently developed, but the growth factor involved in the proliferation of PGCs is largely unknown. In the present study, we investigated the growth effects of chicken stem cell factor (chSCF) on the in vitro proliferation of chicken PGCs. We established two feeder cell lines (buffalo rat liver cells; BRL cells) that stably express the putative secreted form of chSCF (chSCF1-BRL) and membrane bound form of chSCF (chSCF2-BRL). Cultured PGC lines were incubated on chSCF1 or chSCF2-BRL feeder cells with fibroblast growth factor 2 (FGF2), and growth effects of each chSCF isoform were investigated. The in vitro proliferation rate of the PGCs cultured on chSCF2-BRL at 20 days of culture was more than threefold higher than those cultured on chSCF1-BRL cells and more than fivefold higher than those cultured on normal BRL cells. Thus, use of chSCF2-BRL feeder layer was effective for in vitro proliferation of chicken PGCs. However, the acceleration of PGC proliferation on chSCF2-BRL was not observed without FGF2, suggesting that chSCF2 would act as a proliferation co-factor of FGF2. We transferred the PGCs cultured on chSCF2-BRL cells to recipient embryos, generated germline chimeric chickens and assessed the germline competency of cultured PGCs by progeny test. Donor-derived progenies were obtained, and the frequency of germline transmission was 3.39%. The results of this study demonstrate that chSCF2 induces hyperproliferation of chicken PGCs retaining germline competency in vitro in cooperation with FGF2. PMID:26727404

  2. Syndecan-4 proteoliposomes enhance fibroblast growth factor-2 (FGF-2)–induced proliferation, migration, and neovascularization of ischemic muscle

    PubMed Central

    Jang, Eugene; Albadawi, Hassan; Watkins, Michael T.; Edelman, Elazer R.; Baker, Aaron B.

    2012-01-01

    Ischemia of the myocardium and lower limbs is a common consequence of arterial disease and a major source of morbidity and mortality in modernized countries. Inducing neovascularization for the treatment of ischemia is an appealing therapeutic strategy for patients for whom traditional treatment modalities cannot be performed or are ineffective. In the past, the stimulation of blood vessel growth was pursued using direct delivery of growth factors, angiogenic gene therapy, or cellular therapy. Although therapeutic angiogenesis holds great promise for treating patients with ischemia, current methods have not found success in clinical trials. Fibroblast growth factor-2 (FGF-2) was one of the first growth factors to be tested for use in therapeutic angiogenesis. Here, we present a method for improving the biological activity of FGF-2 by codelivering the growth factor with a liposomally embedded coreceptor, syndecan-4. This technique was shown to increase FGF-2 cellular signaling, uptake, and nuclear localization in comparison with FGF-2 alone. Delivery of syndecan-4 proteoliposomes also increased endothelial proliferation, migration, and angiogenic tube formation in response to FGF-2. Using an animal model of limb ischemia, syndecan-4 proteoliposomes markedly improved the neovascularization following femoral artery ligation and recovery of perfusion of the ischemic limb. Taken together, these results support liposomal delivery of syndecan-4 as an effective means to improving the potential of using growth factors to achieve therapeutic neovascularization of ischemic tissue. PMID:22307630

  3. MicroRNAs in the Myocyte Enhancer Factor 2 (MEF2)-regulated Gtl2-Dio3 Noncoding RNA Locus Promote Cardiomyocyte Proliferation by Targeting the Transcriptional Coactivator Cited2.

    PubMed

    Clark, Amanda L; Naya, Francisco J

    2015-09-18

    Understanding cell cycle regulation in postmitotic cardiomyocytes may lead to new therapeutic approaches to regenerate damaged cardiac tissue. We have demonstrated previously that microRNAs encoded by the Gtl2-Dio3 noncoding RNA locus function downstream of the MEF2A transcription factor in skeletal muscle regeneration. We have also reported expression of these miRNAs in the heart. Here we investigated the role of two Gtl2-Dio3 miRNAs, miR-410 and miR-495, in cardiac muscle. Overexpression of miR-410 and miR-495 robustly stimulated cardiomyocyte DNA synthesis and proliferation. Interestingly, unlike our findings in skeletal muscle, these miRNAs did not modulate the activity of the WNT signaling pathway. Instead, these miRNAs targeted Cited2, a coactivator required for proper cardiac development. Consistent with miR-410 and miR-495 overexpression, siRNA knockdown of Cited2 in neonatal cardiomyocytes resulted in robust proliferation. This phenotype was associated with reduced expression of Cdkn1c/p57/Kip2, a cell cycle inhibitor, and increased expression of VEGFA, a growth factor with proliferation-promoting effects. Therefore, miR-410 and miR-495 are among a growing number of miRNAs that have the ability to potently stimulate neonatal cardiomyocyte proliferation.

  4. Regulation of Myocyte Enhancer Factor-2 Transcription Factors by Neurotoxins

    PubMed Central

    She, Hua; Mao, Zixu

    2011-01-01

    Various isoforms of myocyte enhancer factor-2 (MEF2) constitute a group of nuclear proteins found to play important roles in increasing types of cells. In neurons, MEF2s are required to regulate neuronal development, synaptic plasticity, as well as survival. MEF2s promote the survival of several types of neurons under different conditions. In cellular models, negative regulation of MEF2s by stress and toxic signals contributes to neuronal death. In contrast, enhancing MEF2 activity not only protects cultured primary neurons from death in vitro but also attenuates the loss of dopaminergic neurons in substantia nigra pars compacta in a 1-methyl 4-phenyl 1,2,3,6-tetrahydropyridine mouse model of Parkinson’s disease. In this work, the mechanisms of regulation of MEF2 function by several well-known neurotoxins and their implications in various neurodegenerative diseases are reviewed. PMID:21741404

  5. Elevated eukaryotic elongation factor 2 expression is involved in proliferation and invasion of lung squamous cell carcinoma

    PubMed Central

    Hao, LiHong; Hu, Jun; Du, Sha; Zhou, Xin; Zhang, LiYuan; Liu, Lu; Gong, LinLin; Chi, XinMing; Liu, Qiang; Shao, ShuJuan

    2016-01-01

    Eukaryotic elongation factor 2 (EF2), is a critical enzyme solely responsible for catalyzing the translocation of the elongated peptidyl-tRNA from the A to P sites of the ribosome during the process of protein synthesis. EF2 is found to be highly expressed in a variety of malignant tumors and is correlated with cancer cell progression and recurrence. The present study was designed to uncover the function of EF2 on lung squamous cell carcinoma (LSCC) cancer cell growth and progression. Our results from clinical tissue studies showed that EF2 protein was significantly overexpressed in LSCC tissues, compared with the adjacent normal lung tissues, which was confirmed by western blotting and tissue microarray. Forced expression of EF2 resulted in the enhancement of lung squamous carcinoma NCI-H520 cells growth through promotion of G2/M progression in cell cycle, activating Akt and Cdc2/Cyclin B1. In nude mice cancer xenograft model, overexpression of EF2 significantly facilitated cell proliferation in vivo. Furthermore, forced expression of EF2 in the cells increased the capabilities of migration and invasion by changing the expressions of EMT-related proteins and genes. These results provided novel insights into the role of EF2 in tumorigenesis and progression in LSCC. EF2-targeted therapy could become a good strategy for the clinical treatment of LSCC. PMID:27542262

  6. Effects of fibroblast growth factor 2 on osteoblastic proliferation and differentiation by regulating bone morphogenetic protein receptor expression.

    PubMed

    Park, Jun-Beom

    2011-09-01

    Fibroblast growth factors (FGFs) are known to play a critical role in bone growth and development, affecting both osteogenesis and chondrogenesis. Fibroblast growth factor 2 (FGF-2) is produced intracellularly by osteoblasts and secreted into the surrounding matrix in bone.The dose-dependent effects of FGF-2 were tested to examine the relationship between FGF-2 and osteoblast proliferation and differentiation. Tests used included a cell viability test, an alkaline phosphatase activity test, and a Western blot analysis.Cultures growing in the presence of FGF-2 showed an increased value for 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide assay and a decreased value for alkaline phosphatase activity. Results of the Western blot analysis showed that the addition of FGF-2 seems to decrease osteocalcin and bone morphogenetic protein receptor IA.These data show that FGF-2 in the tested dosage within MC3T3-E1 cells seems to affect proliferation and differentiation. Results of the Western blot analysis may add some possible mechanisms, and it may be suggested that treatment of FGF-2 may have an influence on the expression of bone morphogenetic protein receptors in osteoprecursor cells. Further elucidation of the mechanisms related to this mechanism within the in vivo model may be necessary to ascertain greater detail.

  7. Microfluidic Screening Reveals Heparan Sulfate Enhances Human Mesenchymal Stem Cell Growth by Modulating Fibroblast Growth Factor-2 Transport.

    PubMed

    Titmarsh, Drew M; Tan, Clarissa L L; Glass, Nick R; Nurcombe, Victor; Cooper-White, Justin J; Cool, Simon M

    2017-04-01

    Cost-effective expansion of human mesenchymal stem/stromal cells (hMSCs) remains a key challenge for their widespread clinical deployment. Fibroblast growth factor-2 (FGF-2) is a key hMSC mitogen often supplemented to increase hMSC growth rates. However, hMSCs also produce endogenous FGF-2, which critically interacts with cell surface heparan sulfate (HS). We assessed the interplay of FGF-2 with a heparan sulfate variant (HS8) engineered to bind FGF-2 and potentiate its activity. Bone marrow-derived hMSCs were screened in perfused microbioreactor arrays (MBAs), showing that HS8 (50 μg/ml) increased hMSC proliferation and cell number after 3 days, with an effect equivalent to FGF-2 (50 ng/ml). In combination, the effects of HS8 and FGF-2 were additive. Differential cell responses, from upstream to downstream culture chambers under constant flow of media in the MBA, provided insights into modulation of FGF-2 transport by HS8. HS8 treatment induced proliferation mainly in the downstream chambers, suggesting a requirement for endogenous FGF-2 accumulation, whereas responses to FGF-2 occurred primarily in the upstream chambers. Adding HS8 along with FGF-2, however, maximized the range of FGF-2 effectiveness. Measurements of FGF-2 in static cultures then revealed that this was because HS8 caused increased endogenous FGF-2 production and liberated FGF-2 from the cell surface into the supernatant. HS8 also sustained levels of supplemented FGF-2 available over 3 days. These results suggest HS8 enhances hMSC proliferation and expansion by leveraging endogenous FGF-2 production and maximizing the effect of supplemented FGF-2. This is an exciting strategy for cost-effective expansion of hMSCs. Stem Cells Translational Medicine 2017;6:1178-1190.

  8. Identification of a new hybrid serum response factor and myocyte enhancer factor 2-binding element in MyoD enhancer required for MyoD expression during myogenesis.

    PubMed

    L'honore, Aurore; Rana, Vanessa; Arsic, Nikola; Franckhauser, Celine; Lamb, Ned J; Fernandez, Anne

    2007-06-01

    MyoD is a critical myogenic factor induced rapidly upon activation of quiescent satellite cells, and required for their differentiation during muscle regeneration. One of the two enhancers of MyoD, the distal regulatory region, is essential for MyoD expression in postnatal muscle. This enhancer contains a functional divergent serum response factor (SRF)-binding CArG element required for MyoD expression during myoblast growth and muscle regeneration in vivo. Electrophoretic mobility shift assay, chromatin immunoprecipitation, and microinjection analyses show this element is a hybrid SRF- and MEF2 Binding (SMB) sequence where myocyte enhancer factor 2 (MEF2) complexes can compete out binding of SRF at the onset of differentiation. As cells differentiate into postmitotic myotubes, MyoD expression no longer requires SRF but instead MEF2 binding to this dual-specificity element. As such, the MyoD enhancer SMB element is the site for a molecular relay where MyoD expression is first initiated in activated satellite cells in an SRF-dependent manner and then increased and maintained by MEF2 binding in differentiated myotubes. Therefore, SMB is a DNA element with dual and stage-specific binding activity, which modulates the effects of regulatory proteins critical in controlling the balance between proliferation and differentiation.

  9. Dynamic Phosphorylation of the Myocyte Enhancer Factor 2Cα1 Splice Variant Promotes Skeletal Muscle Regeneration and Hypertrophy.

    PubMed

    Baruffaldi, Fiorenza; Montarras, Didier; Basile, Valentina; De Feo, Luca; Badodi, Sara; Ganassi, Massimo; Battini, Renata; Nicoletti, Carmine; Imbriano, Carol; Musarò, Antonio; Molinari, Susanna

    2017-03-01

    The transcription factor MEF2C (Myocyte Enhancer Factor 2C) plays an established role in the early steps of myogenic differentiation. However, the involvement of MEF2C in adult myogenesis and in muscle regeneration has not yet been systematically investigated. Alternative splicing of mammalian MEF2C transcripts gives rise to two mutually exclusive protein variants: MEF2Cα2 which exerts a positive control of myogenic differentiation, and MEF2Cα1, in which the α1 domain acts as trans-repressor of the MEF2C pro-differentiation activity itself. However, MEF2Cα1 variants are persistently expressed in differentiating cultured myocytes, suggesting a role in adult myogenesis. We found that overexpression of both MEF2Cα1/α2 proteins in a mouse model of muscle injury promotes muscle regeneration and hypertrophy, with each isoform promoting different stages of myogenesis. Besides the ability of MEF2Cα2 to increase differentiation, we found that overexpressed MEF2Cα1 enhances both proliferation and differentiation of primary myoblasts, and activates the AKT/mTOR/S6K anabolic signaling pathway in newly formed myofibers. The multiple activities of MEF2Cα1 are modulated by phosphorylation of Ser98 and Ser110, two amino acid residues located in the α1 domain of MEF2Cα1. These specific phosphorylations allow the interaction of MEF2Cα1 with the peptidyl-prolyl isomerase PIN1, a regulator of MEF2C functions. Overall, in this study we established a novel regulatory mechanism in which the expression and the phosphorylation of MEF2Cα1 are critically required to sustain the adult myogenesis. The described molecular mechanism will represent a new potential target for the development of therapeutical strategies to treat muscle-wasting diseases. Stem Cells 2017;35:725-738.

  10. Expression of myocyte enhancer factor-2 and downstream genes in ground squirrel skeletal muscle during hibernation.

    PubMed

    Tessier, Shannon N; Storey, Kenneth B

    2010-11-01

    Myocyte enhancer factor-2 (MEF2) transcription factors regulate the expression of a variety of genes encoding contractile proteins and other proteins associated with muscle performance. We proposed that changes in MEF2 levels and expression of selected downstream targets would aid the skeletal muscle of thirteen-lined ground squirrels (Spermophilus tridecemlineatus) in meeting metabolic challenges associated with winter hibernation; e.g., cycles of torpor-arousal, body temperature that can fall to near 0°C, long periods of inactivity that could lead to atrophy. MEF2A protein levels were significantly elevated when animals were in torpor (maximally 2.8-fold higher than in active squirrels) and the amount of phosphorylated active MEF2A Thr312 increased during entrance into torpor. MEF2C levels also rose significantly during entrance and torpor as did the amount of phosphorylated MEF2C Ser387. Furthermore, both MEF2 members showed elevated amounts in the nuclear fraction during torpor as well as enhanced binding to DNA indicating that MEF2-mediated gene expression was up-regulated in torpid animals. Indeed, the protein products of two MEF2 downstream gene targets increased in muscle during torpor (glucose transporter isoforms 4; GLUT4) or early arousal (myogenic differentiation; MyoD). Significant increases in Glut4 and MyoD mRNA transcript levels correlated with the rise in protein product levels and provided further support for the activation of MEF2-mediated gene expression in the hibernator. Transcript levels of Mef2a and Mef2c also showed time-dependent patterns with levels of both being highest during arousal from torpor. The data suggest a significant role for MEF2-mediated gene transcription in the selective adjustment of muscle protein complement over the course of torpor-arousal cycles.

  11. Myocyte enhancer factor 2c, an osteoblast transcription factor identified by dimethyl sulfoxide (DMSO)-enhanced mineralization.

    PubMed

    Stephens, Alexandre S; Stephens, Sebastien R; Hobbs, Carl; Hutmacher, Deitmar W; Bacic-Welsh, Desa; Woodruff, Maria Ann; Morrison, Nigel A

    2011-08-26

    Rapid mineralization of cultured osteoblasts could be a useful characteristic in stem cell-mediated therapies for fracture and other orthopedic problems. Dimethyl sulfoxide (DMSO) is a small amphipathic solvent molecule capable of stimulating cell differentiation. We report that, in primary human osteoblasts, DMSO dose-dependently enhanced the expression of osteoblast differentiation markers alkaline phosphatase activity and extracellular matrix mineralization. Furthermore, similar DMSO-mediated mineralization enhancement was observed in primary osteoblast-like cells differentiated from mouse mesenchymal cells derived from fat, a promising source of starter cells for cell-based therapy. Using a convenient mouse pre-osteoblast model cell line MC3T3-E1, we further investigated this phenomenon showing that numerous osteoblast-expressed genes were elevated in response to DMSO treatment and correlated with enhanced mineralization. Myocyte enhancer factor 2c (Mef2c) was identified as the transcription factor most induced by DMSO, among the numerous DMSO-induced genes, suggesting a role for Mef2c in osteoblast gene regulation. Immunohistochemistry confirmed expression of Mef2c in osteoblast-like cells in mouse mandible, cortical, and trabecular bone. shRNAi-mediated Mef2c gene silencing resulted in defective osteoblast differentiation, decreased alkaline phosphatase activity, and matrix mineralization and knockdown of osteoblast specific gene expression, including osteocalcin and bone sialoprotein. A flow on knockdown of bone-specific transcription factors, Runx2 and osterix by shRNAi knockdown of Mef2c, suggests that Mef2c lies upstream of these two important factors in the cascade of gene expression in osteoblasts.

  12. ENHANCING ADVANCED CANDU PROLIFERATION RESISTANCE FUEL WITH MINOR ACTINIDES

    SciTech Connect

    Gray S. Chang

    2010-05-01

    The advanced nuclear system will significantly advance the science and technology of nuclear energy systems and to enhance the spent fuel proliferation resistance. Minor actinides (MA) are viewed more as a resource to be recycled, and transmuted to less hazardous and possibly more useful forms, rather than simply disposed of as a waste stream in an expensive repository facility. MAs can play a much larger part in the design of advanced systems and fuel cycles, not only as additional sources of useful energy, but also as direct contributors to the reactivity control of the systems into which they are incorporated. In this work, an Advanced CANDU Reactor (ACR) fuel unit lattice cell model with 43 UO2 fuel rods will be used to investigate the effectiveness of a Minor Actinide Reduction Approach (MARA) for enhancing proliferation resistance and improving the fuel cycle performance. The main MARA objective is to increase the 238Pu / Pu isotope ratio by using the transuranic nuclides (237Np and 241Am) in the high burnup fuel and thereby increase the proliferation resistance even for a very low fuel burnup. As a result, MARA is a very effective approach to enhance the proliferation resistance for the on power refueling ACR system nuclear fuel. The MA transmutation characteristics at different MA loadings were compared and their impact on neutronics criticality assessed. The concept of MARA, significantly increases the 238Pu/Pu ratio for proliferation resistance, as well as serves as a burnable absorber to hold-down the initial excess reactivity. It is believed that MARA can play an important role in atoms for peace and the intermediate term of nuclear energy reconnaissance.

  13. Enhancing VVER Annular Proliferation Resistance Fuel with Minor Actinides

    SciTech Connect

    G. S. Chang

    2007-06-01

    Key aspects of the Global Nuclear Energy Partnership (GNEP) are to significantly advance the science and technology of nuclear energy systems and the Advanced Fuel Cycle (AFC) program. The merits of nuclear energy are the high-density energy, and low environmental impacts i.e. almost zero greenhouse gas emission. Planned efforts involve near-term and intermediate-term improvements in fuel utilization and recycling in current LWR as well as the longer-term development of new nuclear energy systems that offer much improved fuel utilization and proliferation resistance, along with continued advances in operational safety. The challenges are solving the energy needs of the world, protection against nuclear proliferation, the problem of nuclear waste, and the global environmental problem. To reduce the spent fuel for storage and enhance the proliferation resistance for the intermediate-term, there are two major approaches (a) increase the discharged spent fuel burnup in the advanced LWR (Gen-III Plus), which not only can reduce the spent fuel for storage, but also increase the 238Pu and 240Pu isotopes ratio to enhance the proliferation resistance, (b) use of transuranic nuclides (237Np and 241Am) in the high burnup fuel, which can drastically increase the proliferation resistance isotope 238Pu /Pu ratio. For future advanced nuclear systems, the minor actinides are viewed more as a resource to be recycled, or transmuted to less hazardous and possibly more useful forms, rather than simply as a waste stream to be disposed of in expensive repository facilities. In this paper, a typical pressurized water reactor (PWR) VVER-1000 annular fuel unit lattice cell model with UO2 fuel pins will be used to investigate the effectiveness of minor actinide reduction approach (MARA) for enhancing proliferation resistance and improving the fuel cycle performance. We concluded that the concept of MARA, involves the use of transuranic nuclides (237Np and/or 241Am), can not only drastically

  14. FOXM1 regulates expression of eukaryotic elongation factor 2 kinase and promotes proliferation, invasion and tumorgenesis of human triple negative breast cancer cells

    PubMed Central

    Hamurcu, Zuhal; Ashour, Ahmed; Kahraman, Nermin; Ozpolat, Bulent

    2016-01-01

    Eukaryotic elongation factor 2 kinase (eEF2K), an emerging molecular target for cancer therapy, contributes to cancer proliferation, cell survival, tumorigenesis, and invasion, disease progression and drug resistance. Although eEF2K is highly up-regulated in various cancers, the mechanism of gene regulation has not been elucidated. In this study, we examined the role of Forkhead Box M1 (FOXM1) proto-oncogenic transcription factor in triple negative breast cancer (TNBC) cells and the regulation of eEF2K. We found that FOXM1 is highly upregulated in TNBC and its knockdown by RNA interference (siRNA) significantly inhibited eEF2K expression and suppressed cell proliferation, colony formation, migration, invasion and induced apoptotic cell death, recapitulating the effects of eEF2K inhibition. Knockdown of FOXM1 inhibited regulators of cell cycle, migration/invasion and survival, including cyclin D1, Src and MAPK-ERK signaling pathways, respectively. We also demonstrated that FOXM1 (1B and 1C isoforms) directly binds to and transcriptionally regulates eEF2K gene expression by chromatin immunoprecipitation (ChIP) and luciferase gene reporter assays. Furthermore, in vivo inhibition of FOXM1 by liposomal siRNA-nanoparticles suppressed growth of MDA-MB-231 TNBC tumor xenografts in orthotopic models. In conclusion, our study provides the first evidence about the transcriptional regulation of eEF2K in TNBC and the role of FOXM1 in mediating breast cancer cell proliferation, survival, migration/invasion, progression and tumorgenesis and highlighting the potential of FOXM1/eEF2K axis as a molecular target in breast and other cancers. PMID:26918606

  15. Enhancing BWR proliferation resistance fuel with minor actinides

    NASA Astrophysics Data System (ADS)

    Chang, Gray S.

    2009-03-01

    To reduce spent fuel for storage and enhance the proliferation resistance for the intermediate-term, there are two major approaches (a) increase the discharged spent fuel burnup in the advanced light water reactor- LWR (Gen-III Plus), which not only can reduce the spent fuel for storage, but also increase the 238Pu isotopes ratio to enhance the proliferation resistance, and (b) use of transuranic nuclides ( 237Np and 241Am) in the high burnup fuel, which can drastically increase the proliferation resistance isotope ratio of 238Pu/Pu. For future advanced nuclear systems, minor actinides (MA) are viewed more as a resource to be recycled, and transmuted to less hazardous and possibly more useful forms, rather than simply disposed of as a waste stream in an expensive repository facility. As a result, MAs play a much larger part in the design of advanced systems and fuel cycles, not only as additional sources of useful energy, but also as direct contributors to the reactivity control of the systems into which they are incorporated. In the study, a typical boiling water reactor (BWR) fuel unit lattice cell model with UO 2 fuel pins will be used to investigate the effectiveness of minor actinide reduction approach (MARA) for enhancing proliferation resistance and improving the fuel cycle performance in the intermediate-term goal for future nuclear energy systems. To account for the water coolant density variation from the bottom (0.76 g/cm 3) to the top (0.35 g/cm 3) of the core, the axial coolant channel and fuel pin were divided to 24 nodes. The MA transmutation characteristics at different elevations were compared and their impact on neutronics criticality discussed. The concept of MARA, which involves the use of transuranic nuclides ( 237Np and/or 241Am), significantly increases the 238Pu/Pu ratio for proliferation resistance, as well as serves as a burnable absorber to hold-down the initial excess reactivity. It is believed that MARA can play an important role in

  16. Enhancing BWR Proliferation Resistance Fuel with Minor Actinides

    SciTech Connect

    Gray S. Chang

    2009-03-01

    To reduce spent fuel for storage and enhance the proliferation resistance for the intermediate-term, there are two major approaches (a) increase the discharged spent fuel burnup in the advanced light water reactor- LWR (Gen-III Plus), which not only can reduce the spent fuel for storage, but also increase the 238Pu isotopes ratio to enhance the proliferation resistance, and (b) use of transuranic nuclides (237Np and 241Am) in the high burnup fuel, which can drastically increase the proliferation resistance isotope ratio of 238Pu/Pu. For future advanced nuclear systems, minor actinides (MA) are viewed more as a resource to be recycled, and transmuted to less hazardous and possibly more useful forms, rather than simply disposed of as a waste stream in an expensive repository facility. As a result, MAs play a much larger part in the design of advanced systems and fuel cycles, not only as additional sources of useful energy, but also as direct contributors to the reactivity control of the systems into which they are incorporated. In the study, a typical boiling water reactor (BWR) fuel unit lattice cell model with UO2 fuel pins will be used to investigate the effectiveness of minor actinide reduction approach (MARA) for enhancing proliferation resistance and improving the fuel cycle performance in the intermediate-term goal for future nuclear energy systems. To account for the water coolant density variation from the bottom (0.76 g/cm3) to the top (0.35 g/cm3) of the core, the axial coolant channel and fuel pin were divided to 24 nodes. The MA transmutation characteristics at different elevations were compared and their impact on neutronics criticality discussed. The concept of MARA, which involves the use of transuranic nuclides (237Np and/or 241Am), significantly increases the 238Pu/Pu ratio for proliferation resistance, as well as serves as a burnable absorber to hold-down the initial excess reactivity. It is believed that MARA can play an important role in atoms

  17. Enhancing BWR Proliferation Resistance Fuel with Minor Actinides

    SciTech Connect

    Gray S. Chang

    2008-07-01

    Key aspects of the Global Nuclear Energy Partnership (GNEP) are to significantly advance the science and technology of nuclear energy systems and the Advanced Fuel Cycle (AFC) program. It consists of both innovative nuclear reactors and innovative research in separation and transmutation. To accomplish these goals, international cooperation is very important and public acceptance is crucial. The merits of nuclear energy are high-density energy, with low environmental impacts (i.e. almost zero greenhouse gas emission). Planned efforts involve near-term and intermediate-term improvements in fuel utilization and recycling in current light water reactors (LWRs) as well as the longer-term development of new nuclear energy systems that offer much improved fuel utilization and proliferation resistance, along with continued advances in operational safety. The challenges are solving the energy needs of the world, protection against nuclear proliferation, the problem of nuclear waste, and the global environmental problem. To reduce spent fuel for storage and enhance the proliferation resistance for the intermediate-term, there are two major approaches (a) increase the discharged spent fuel burnup in the advanced LWR (Gen-III Plus), which not only can reduce the spent fuel for storage, but also increase the 238Pu and 240Pu isotopes ratio to enhance the proliferation resistance, and (b) use of transuranic nuclides (237Np and 241Am) in the high burnup fuel, which can drastically increase the proliferation resistance isotope ratio of 238Pu /Pu. For future advanced nuclear systems, the minor actinides (MA) are viewed more as a resource to be recycled, or transmuted to less hazardous and possibly more useful forms, rather than simply as a waste stream to be disposed of in expensive repository facilities. As a result, MAs play a much larger part in the design of advanced systems and fuel cycles, not only as additional sources of useful energy, but also as direct contributors to the

  18. Enhanced osteoblast proliferation and collagen gene expression by estradiol

    SciTech Connect

    Ernest, M.; Schmid, Ch.; Froesch, E.R. )

    1988-04-01

    Estrogens play a crucial role in the development of postmenopausal osteoporosis. However, the mechanism by which estrogens exert their effects on bone is unknown. To examine possible direct effects of 17{beta}-estradiol on bone-forming cells, the authors used pure rat osteoblast-like cells in vitro as a model. Osteoblast-like cells prepared from calvaria of newborn rats were cultured serum-free in methylcellulose-containing medium for 21 days. Osteoblast-like cells proliferate selectively into clonally derived cell clusters of spherical morphorlogy. 17{beta}-Estradiol at concentrations of 0.1 nM and 1 nM enhanced osteoblast-like cell proliferation by 41% and 68% above vehicle-treated controls. The biologically inactive stereoisomer 17{alpha}-estradiol (same concentrations) had no effect. Moreover, the antiestrogen tamoxifen abolished the stimulation of osteoblast-like cell proliferation by 17{beta}-estradiol. After 21 days of culture, RNA was prepared and analyzed in a dot-hybridization assay for the abundance of pro{alpha}1(I) collagen mRNA. Steady-state mRNA levels were increased in cultures treated with 17{beta}-estradiol in a dose-dependent manner with maximal stimulation at 1 nM and 10 nM. At the same concentrations, the percentage of synthesized protein (labeled by ({sup 3}H)proline pulse) that was digestible by collagenase was increased, indicating that 17{beta}-estradiol acts as pretranslational levels to enhance synthesis of bone collagen. These data show that the osteoblast is a direct target for 17{beta}-estradiol.

  19. Nuclear Factor Erythroid 2-Related Factor 2 Drives Podocyte-Specific Expression of Peroxisome Proliferator-Activated Receptor γ Essential for Resistance to Crescentic GN

    PubMed Central

    Bollee, Guillaume; Lenoir, Olivia; Dhaun, Neeraj; Camus, Marine; Chipont, Anna; Flosseau, Kathleen; Mandet, Chantal; Yamamoto, Masayuki; Karras, Alexandre; Thervet, Eric; Bruneval, Patrick; Nochy, Dominique; Mesnard, Laurent

    2016-01-01

    Necrotizing and crescentic rapidly progressive GN (RPGN) is a life-threatening syndrome characterized by a rapid loss of renal function. Evidence suggests that podocyte expression of the transcription factor peroxisome proliferator-activated receptor γ (PPARγ) may prevent podocyte injury, but the function of glomerular PPARγ in acute, severe inflammatory GN is unknown. Here, we observed marked loss of PPARγ abundance and transcriptional activity in glomerular podocytes in experimental RPGN. Blunted expression of PPARγ in podocyte nuclei was also found in kidneys from patients diagnosed with crescentic GN. Podocyte-specific Pparγ gene targeting accentuated glomerular damage, with increased urinary loss of albumin and severe kidney failure. Furthermore, a PPARγ gain-of-function approach achieved by systemic administration of thiazolidinedione (TZD) failed to prevent severe RPGN in mice with podocyte-specific Pparγ gene deficiency. In nuclear factor erythroid 2-related factor 2 (NRF2)–deficient mice, loss of podocyte PPARγ was observed at baseline. NRF2 deficiency markedly aggravated the course of RPGN, an effect that was partially prevented by TZD administration. Furthermore, delayed administration of TZD, initiated after the onset of RPGN, still alleviated the severity of experimental RPGN. These findings establish a requirement for the NRF2–PPARγ cascade in podocytes, and we suggest that these transcription factors have a role in augmenting the tolerance of glomeruli to severe immune-complex mediated injury. The NRF2–PPARγ pathway may be a therapeutic target for RPGN. PMID:25999406

  20. Hypoxia-inducible factor-2 alpha promotes the proliferation of human placenta-derived mesenchymal stem cells through the MAPK/ERK signaling pathway

    PubMed Central

    Zhu, Chengxing; Yu, Jiong; Pan, Qiaoling; Yang, Jinfeng; Hao, Guangshu; Wang, Yingjie; Li, Lanjuan; Cao, Hongcui

    2016-01-01

    Human placenta-derived mesenchymal stem cells (hPMSCs) reside in a physiologically low-oxygen microenvironment. Hypoxia influences a variety of stem cell cellular activities, frequently involving hypoxia-inducible factor-2 alpha (HIF-2α). This research showed that hPMSCs cultured in hypoxic conditions (5% O2) exhibited a more naïve morphology and had a higher proliferative capability and higher HIF-2α expression than hPMSCs cultured in normoxic conditions (21% O2). Similar to the hypoxic cultures, hPMSCs over-expressing HIF-2α showed higher proliferative potential and higher expression of CCND1 (CyclinD1), MYC (c-Myc), POU5F1 (Oct4) and the components of the MAPK/ERK pathway. In contrast, these genes were down-regulated in the HIF-2α-silenced hPMSCs. After adding the MAPK/ERK inhibitor PD0325901, cell growth and the expression of CCND1 and MYC were inhibited. Furthermore, the chromatin immunoprecipitation (ChIP) assay and electrophoretic mobility shift assay (EMSA) showed that HIF-2α bound to the MAPK3 (ERK1) promoter, indicative of its direct regulation of MAPK/ERK components at the transcriptional level during hPMSC expansion. Taken together, our results suggest that HIF-2α facilitated the preservation of hPMSC stemness and promoted their proliferation by regulating CCND1 and MYC through the MAPK/ERK signaling pathway. PMID:27765951

  1. Rebamipide Delivered by Brushite Cement Enhances Osteoblast and Macrophage Proliferation

    PubMed Central

    Pujari-Palmer, Michael; Pujari-Palmer, Shiuli; Engqvist, Håkan; Karlsson Ott, Marjam

    2015-01-01

    Many of the bioactive agents capable of stimulating osseous regeneration, such as bone morphogenetic protein-2 (BMP-2) or prostaglandin E2 (PGE2), are limited by rapid degradation, a short bioactive half-life at the target site in vivo, or are prohibitively expensive to obtain in large quantities. Rebamipide, an amino acid modified hydroxylquinoline, can alter the expression of key mediators of bone anabolism, cyclo-oxygenase 2 (COX-2), BMP-2 and vascular endothelial growth factor (VEGF), in diverse cell types such as mucosal and endothelial cells or chondrocytes. The present study investigates whether Rebamipide enhances proliferation and differentiation of osteoblasts when delivered from brushite cement. The reactive oxygen species (ROS) quenching ability of Rebampide was tested in macrophages as a measure of bioactivity following drug release incubation times, up to 14 days. Rebamipide release from brushite occurrs via non-fickian diffusion, with a rapid linear release of 9.70% ±0.37% of drug per day for the first 5 days, and an average of 0.5%-1% per day thereafter for 30 days. Rebamipide slows the initial and final cement setting time by up to 3 and 1 minute, respectively, but does not significantly reduce the mechanical strength below 4% (weight percentage). Pre-osteoblast proliferation increases by 24% upon exposure to 0.4uM Rebamipide, and by up to 73% when Rebamipide is delivered via brushite cement. Low doses of Rebamipide do not adversely affect peak alkaline phosphatase activity in differentiating pre-osteoblasts. Rebamipide weakly stimulates proliferation in macrophages at low concentrations (118 ±7.4% at 1uM), and quenches ROS by 40-60%. This is the first investigation of Rebamipide in osteoblasts. PMID:26023912

  2. Nanovesicles engineered from ES cells for enhanced cell proliferation.

    PubMed

    Jeong, Dayeong; Jo, Wonju; Yoon, Jaewoong; Kim, Junho; Gianchandani, Sachi; Gho, Yong Song; Park, Jaesung

    2014-11-01

    Extracellular vesicles (Exosomes and microvesicles) have drawn wide attentions in both diagnostic and therapeutic applications, since they are considered to shuttle biological signals intercellularly. However, further research on exosomes is limited by their rarity and heterogeneity even after lengthy isolation processes. In particular, these limitations are challenging in therapeutic applications. To meet these demands, cell-derived nanovesicles that mimic exosomes were generated by extruding living embryonic stem cells through micro-filters. These nanovesicles have an enclosed lipid bilayer and contain cellular contents. The present study investigated the ability of these nanovesicles to improve proliferation by treating primary murine skin fibroblasts with the nanovesicles. The treated skin fibroblasts showed higher expression levels of mRNA, VEGF-α, protein levels of TGF-β collagen I, PCNA, and Ki-67, as well as enhanced cell proliferation rate and number, compared to non-treated cells. The results indicate that treatment with the nanovesicles could potentially contribute to recovery or wound healing process of tissues.

  3. Polymorphism of chicken myocyte-specific enhancer-binding factor 2A gene and its association with chicken carcass traits.

    PubMed

    Zhou, Yan; Liu, Yiping; Jiang, Xiaosong; Du, Huarui; Li, Xiaocheng; Zhu, Qing

    2010-01-01

    Myocyte-specific enhancer-binding factor 2A (MEF2A) gene is a member of the myocyte-specific enhancer-binding factor 2 (MEF2) protein family which involved in vertebrate skeletal muscle development and differentiation. The aim of the current study is to investigate the potential associations between MEF2A gene SNPs (single nucleotide polymorphisms) and the carcass traits in 471 chicken samples from four populations. Three new SNPs (T46023C, A72626G, and T89232G) were detected in the chicken MEF2A gene. The T46023C genotypes were associated with live body weight (BW), carcass weight (CW), eviscerated weight, semi-eviscerated weight (SEW), and leg muscle weight (LMW) (P < 0.05); the A72626G genotypes were associated with BW, CW, LMW (P < 0.01) and breast muscle weight (BMW), leg muscle percentage (LMP) (P < 0.05); whereas the T89232G genotypes were associated with carcass percentage (CP) and semi-eviscerated percentage (SEP) (P < 0.05). The haplotypes constructed on the three SNPs were associated with BW, CW, LMW (P < 0.01), SEW, BMW, CP (P < 0.05). Significantly and suggestive dominant effects of diplotype H1H2 were observed for BW, CW, SEW, BMW and CP, whereas diplotype H5H5 had a negative effect on BW, CW, SEW, BMW and LMW. Our results suggest that the MEF2A gene may be a potential marker affecting the muscle trait of chickens.

  4. Heat shock factor 2 is associated with the occurrence of lung cancer by enhancing the expression of heat shock proteins

    PubMed Central

    Zhong, Yun-Hua; Cheng, Hong-Zhong; Peng, Hao; Tang, Shi-Cong; Wang, Ping

    2016-01-01

    Cancer is the leading cause of morbidity and mortality worldwide, particularly lung cancer. Heat shock proteins and their upstream heat shock factors are involved in the occurrence of cancer and have been widely researched. However, the role of heat shock factor 2 (HSF2) in lung cancer remains unclear. In the present study, expression levels of HSF2 in lung cancer tissues from 50 lung cancer patients were detected by reverse transcription quantitative polymerase chain reaction, and 76% (38/50) were upregulated compared with the matched normal tissues. This suggested possible involvement of HSF2 in lung cancer. To additionally investigate the role of HSF2 in lung cancer occurrence, a plasmid encoding HSF2 was constructed. HSF2 was over expressed in normal lung epithelial BEAS-2B cells and lung cancer A549 cells. The results showed that HSF2 overexpression promoted cell proliferation and cell migration in BEAS-2B and A549 cells. Additional experiments showed that the HSF2-induced cell proliferation and cell migration were dependent on induction of HSPs, particularly HSP27 and HSP90, as co-transfection of HSP27 small interfering RNA (siRNA) or HSP90 siRNA attenuated HSF2-induced cell growth and migration. In conclusion, the present study showed that HSF2 is aberrantly expressed in lung cancer, and it may be an upstream regulator of HSPs, which may strongly affect cell growth and cell migration. Additional studies are required to explain the detailed mechanism between lung cancer, HSF2, HSPs and other possible signaling pathways. PMID:28101237

  5. Exogenous insulin-like growth factor 2 administration enhances memory consolidation and persistence in a time-dependent manner.

    PubMed

    Lee, Younghwan; Lee, Young Woo; Gao, Qingtao; Lee, Younghwa; Lee, Hyung Eun; Ryu, Jong Hoon

    2015-10-05

    Memory consolidation is an important process for the formation of long-term memory. We have previously reported that mature brain-derived neurotrophic factor enhances memory consolidation within 9h after initial learning. Recent studies suggest that insulin-like growth factor 2 (IGF2) significantly enhances memory consolidation and prevents forgetting. Thus, we hypothesized that IGF2 exerts its activity on cognitive performance in a time-dependent manner as observed in our previous study. In the one-trial step-through inhibitory avoidance task, we demonstrate that a bilateral injection of IGF2 into the dorsal hippocampus 6 or 9 h after training significantly enhanced the step-through latencies compared with the vehicle-treated controls in the retention trial, which was conducted 24 h after the acquisition trial. However, 12h post-training, IGF2 injection did not increase the step-through latencies. Intriguingly, in the retention trial at 21 days after the training, hippocampal IGF2 injection 6, 9 or 12 h after the acquisition trial significantly increased the step-through latencies compared with the vehicle-treated controls. IGF2 administration at 9 h and 12 h after the acquisition trial significantly increased discrimination index and exploration time on the novel-located object in the test trial at 24 h and 21 days, respectively, after the acquisition trial in the novel location recognition task. In addition, IGF2-induced an increase in the step-through latencies in the retention trial 24 h or 21 days, respectively, after the initial learning was completely abolished by co-injected anti-IGF2 receptor antibody. These results suggest that IGF2 enhances memory consolidation within 9h after initial learning, and increased IGF2 within the 12 h after the acquisition trial, which represents a delayed consolidation phase, is also critical for memory persistence.

  6. PC4 Coactivates MyoD by Relieving the Histone Deacetylase 4-Mediated Inhibition of Myocyte Enhancer Factor 2C

    PubMed Central

    Micheli, Laura; Leonardi, Luca; Conti, Filippo; Buanne, Pasquale; Canu, Nadia; Caruso, Maurizia; Tirone, Felice

    2005-01-01

    Histone deacetylase 4 (HDAC4) negatively regulates skeletal myogenesis by associating with the myocyte enhancer factor 2 (MEF2) transcription factors. Our data indicate that the gene PC4 (interferon-related developmental regulator 1 [IFRD1], Tis7), which we have previously shown to be required for myoblast differentiation, is both induced by MyoD and potentiates the transcriptional activity of MyoD, thus revealing a positive regulatory loop between these molecules. Enhancement by PC4 of MyoD-dependent activation of muscle gene promoters occurs selectively through MEF2 binding sites. Furthermore, PC4 localizes in the nucleus of differentiating myoblasts, associates with MEF2C, and is able to counteract the HDAC4-mediated inhibition of MEF2C. This latter action can be explained by the observed ability of PC4 to dose dependently displace HDAC4 from MEF2C. Consistently, we have observed that (i) the region of PC4 that binds MEF2C is sufficient to counteract the inhibition by HDAC4; (ii) PC4, although able to bind HDAC4, does not inhibit the enzymatic activity of HDAC4; and (iii) PC4 overcomes the inhibition mediated by the amino-terminal domain of HDAC4, which associates with MEF2C but not with PC4. Together, our findings strongly suggest that PC4 acts as a coactivator of MyoD and MEF2C by removing the inhibitory effect of HDAC4, thus exerting a pivotal function during myogenesis. PMID:15743821

  7. Vascular endothelial growth factor and fibroblast growth factor 2 delivery from spinal cord bridges to enhance angiogenesis following injury.

    PubMed

    De Laporte, Laura; des Rieux, Anne; Tuinstra, Hannah M; Zelivyanskaya, Marina L; De Clerck, Nora M; Postnov, Andrei A; Préat, Véronique; Shea, Lonnie D

    2011-09-01

    The host response to spinal cord injury can lead to an ischemic environment that can induce cell death and limits cell transplantation approaches to promote spinal cord regeneration. Spinal cord bridges that provide a localized and sustained release of vascular endothelial growth factor (VEGF) and fibroblast growth factor 2 (FGF-2) were investigated for their ability to promote angiogenesis and nerve growth within the injury. Bridges were fabricated by fusion of poly(lactide-co-glycolide) microspheres using a gas foaming/particulate leaching technique, and proteins were incorporated by encapsulation into the microspheres and/or mixing with the microspheres before foaming. Compared to the mixing method, encapsulation reduced the losses during leaching and had a slower protein release, while VEGF was released more rapidly than FGF-2. In vivo implantation of bridges loaded with VEGF enhanced the levels of VEGF within the injury at 1 week, and bridges releasing VEGF and FGF-2 increased the infiltration of endothelial cells and the formation of blood vessel at 6 weeks postimplantation. Additionally, substantial neurofilament staining was observed within the bridge; however, no significant difference was observed between bridges with or without protein. Bridges releasing angiogenic factors may provide an approach to overcome an ischemic environment that limits regeneration and cell transplantation-based approaches.

  8. Localization of myocyte enhancer factor 2 in the rodent forebrain: regionally-specific cytoplasmic expression of MEF2A.

    PubMed

    Neely, M Diana; Robert, Elizabeth M; Baucum, Anthony J; Colbran, Roger J; Muly, E Chris; Deutch, Ariel Y

    2009-06-05

    The transcription factor myocyte enhancer factor 2 (MEF2) is expressed throughout the central nervous system, where four MEF2 isoforms play important roles in neuronal survival and differentiation and in synapse formation and maintenance. It is therefore somewhat surprising that there is a lack of detailed information on the localization of MEF2 isoforms in the mammalian brain. We have analyzed the regional, cellular, and subcellular expression of MEF2A and MEF2D in the rodent brain. These two MEF2 isoforms were co-expressed in virtually all neurons in the cortex and the striatum, but were not detected in astrocytes. MEF2A and MEF2D were localized to the nuclei of neurons in many forebrain areas, consistent with their roles as transcriptional regulators. However, in several subcortical sites we observed extensive cytoplasmic expression of MEF2A but not MEF2D. MEF2A was particularly enriched in processes of neurons in the lateral septum and bed nucleus of the stria terminalis, as well as in several other limbic sites, including the central amygdala and paraventricular nuclei of the hypothalamus and thalamus. Ultrastructural examination similarly revealed MEF2A-ir in axons and dendrites as well as MEF2A-ir nuclei in the lateral septum and bed nucleus of the stria terminalis neurons. This study demonstrates for the first time extensive cytoplasmic localization of a MEF2 transcription factor in the mammalian brain in vivo. The extranuclear localization of MEF2A suggests novel roles for MEF2A in specific neuronal populations.

  9. MECHANISMS INVOLVED IN THE ENHANCED SUSCEPTIBILITY OF SENESCENT RATS TO THE HEPATOCARCINOGENIC EFFECT OF PEROXISOME PROLIFERATORS: ROLE OF PEROXISOME PROLIFERATOR-ACTIVATED RECEPTOR ALPHA (PPARA), CELL PROLIFERATION AND OXIDATIVE STRESS

    EPA Science Inventory

    Mechanisms involved in the ENHANCED SUSCEPTIBILITY of SENESCENT Rats TO THE HEPATOCARCINOGENIC EFFECT OF PEROXISOME PROLIFERATORS: Role of peroxisome proliferator-activated receptor alpha (PPARa), cell proliferation and oxidative stress

    Jihan A. Youssef1, Pierre Ammann2, B...

  10. Localized Ultrasound Enhances Delivery of Rapamycin from Microbubbles to Prevent Smooth Muscle Proliferation

    PubMed Central

    Phillips, Linsey C.; Klibanov, Alexander L.; Wamhoff, Brian R.; Hossack, John A.

    2011-01-01

    Microbubble contrast agents have been shown to enhance reagent delivery when activated by ultrasound. We hypothesized that ultrasound would enhance delivery of rapamycin, an antiproliferative agent, from the shell of microbubbles, thus reducing proliferation of vascular smooth muscle cells. Our objective was to determine optimal ultrasound parameters that maximized therapeutic efficacy, maintained cell adherence, and minimized the drug exposure time. In vitro assays determined that ultrasound (1 MHz, 0.5% duty cycle) is required to successfully deliver rapamycin from microbubbles and reduce proliferation. Co-injection of rapamycin with control microbubbles did not result in a reduction in proliferation. Successful reduction in proliferation (>50%) required pulses at least 10 cycles in length and at least 300 kPa peak negative pressure at which point 90% of cells remained adherent. The anti-proliferative effect was also localized within a 6mm wide zone by focusing the ultrasound beam. PMID:21549778

  11. Clopidogrel Enhances Mesenchymal Stem Cell Proliferation Following Periodontitis

    PubMed Central

    Coimbra, L.S.; Steffens, J.P.; Alsadun, S.; Albiero, M.L.; Rossa, C.; Pignolo, R.J.; Spolidorio, L.C.; Graves, D.T.

    2015-01-01

    Bone formation is dependent on the differentiation of osteoblasts from mesenchymal stem cells (MSCs). In addition to serving as progenitors, MSCs reduce inflammation and produce factors that stimulate tissue formation. Upon injury, MSCs migrate to the periodontium, where they contribute to regeneration. We examined the effect of clopidogrel and aspirin on MSCs following induction of periodontitis in rats by placement of ligatures. We showed that after the removal of ligatures, which induces resolution of periodontal inflammation, clopidogrel had a significant effect on reducing the inflammatory infiltrate. It also increased the number of osteoblasts and MSCs. Mechanistically, the latter was linked to increased proliferation of MSCs in vivo and in vitro. When given prior to inducing periodontitis, clopidogrel had little effect on MSC or osteoblasts numbers. Applying aspirin before or after induction of periodontitis did not have a significant effect on the parameters measured. These results suggest that clopidogrel may have a positive effect on MSCs in conditions where a reparative process has been initiated. PMID:26220958

  12. Prostaglandin E2 released from activated microglia enhances astrocyte proliferation in vitro

    SciTech Connect

    Zhang Dan; Hu Xiaoming; Qian Li; Wilson, Belinda; Lee, Christopher; Flood, Patrick; Langenbach, Robert; Hong, J.-S.

    2009-07-01

    Microglial activation has been implicated in many astrogliosis-related pathological conditions including astroglioma; however, the detailed mechanism is not clear. In this study, we used primary enriched microglia and astrocyte cultures to determine the role of microglial prostaglandin E{sub 2} (PGE{sub 2}) in the proliferation of astrocytes. The proliferation of astrocytes was measured by BrdU incorporation. The level of PGE{sub 2} was measured by ELISA method. Pharmacological inhibition or genetic ablation of COX-2 in microglia were also applied in this study. We found that proliferation of astrocytes increased following lipopolysaccharide (LPS) treatment in the presence of microglia. Furthermore, increased proliferation of astrocytes was observed in the presence of conditioned media from LPS-treated microglia. The potential involvement of microglial PGE{sub 2} in enhanced astrocyte proliferation was suggested by the findings that PGE{sub 2} production and COX-2 expression in microglia were increased by LPS treatment. In addition, activated microglia-induced increases in astrocyte proliferation were blocked by the PGE{sub 2} antagonist AH6809, COX-2 selective inhibitor DuP-697 or by genetic knockout of microglial COX-2. These findings were further supported by the finding that addition of PGE{sub 2} to the media significantly induced astrocyte proliferation. These results indicate that microglial PGE{sub 2} plays an important role in astrocyte proliferation, identifying PGE{sub 2} as a key neuroinflammatory molecule that triggers the pathological response related to uncontrollable astrocyte proliferation. These findings are important in elucidating the role of activated microglia and PGE{sub 2} in astrocyte proliferation and in suggesting a potential avenue in the use of anti-inflammatory agents for the therapy of astroglioma.

  13. Silencing myotubularin related protein 7 enhances proliferation and early differentiation of C2C12 myoblast.

    PubMed

    Yuan, Zhuning; Chen, Yaosheng; Zhang, Xumeng; Zhou, Xingyu; Li, Mingsen; Chen, Hu; Wu, Ming; Zhang, Ying; Mo, Delin

    2017-03-11

    Myotubularin related protein 7 (MTMR7) is a key member of the highly conserved myotubularin related proteins (MTMRs) family, which has phosphatase activity. MTMR7 was increased during myoblast differentiation and exhibited high expression level at primary fibers formation stages in pigs. This suggests that MTMR7 may be involved in myogenesis. In our study, we investigated the roles of MTMR7 on proliferation and differentiation of C2C12 myoblasts. Knocking down MTMR7 not only enhanced myoblast early differentiation via altering the expression of Myf5, but also promoted myoblast proliferation through increasing cyclinA2 expression. The improved proliferation capacity was related to the increased phosphorylation of AKT. Taken together, our research demonstrates that MTMR7 plays an important role in proliferation and early differentiation of C2C12 myoblast.

  14. Mimosine, the Allelochemical from the leguminous tree Leucaena leucocephala, selectively enhances cell proliferation in dinoflagellates.

    PubMed

    Yeung, Patrick K K; Wong, Francis T W; Wong, Joseph T Y

    2002-10-01

    Mimosine, the allelochemical from the leguminous tree Leucaena leucocephala, is toxic to most terrestrial animals and plants. We report here that while mimosine inhibits major phytoplankton groups, it enhances cell proliferation in dinoflagellates. On addition to coastal seawater samples, mimosine is able to confer a growth advantage to dinoflagellates. The use of mimosine will promote the isolation and culture of this group of phytoplankton.

  15. Oxidized LDL enhances stretch-induced smooth muscle cell proliferation through alterations in nuclear protein import.

    PubMed

    Chahine, Mirna N; Dibrov, Elena; Blackwood, David P; Pierce, Grant N

    2012-12-01

    Mechanical stress contributes to hypertension and atherosclerosis partly through the stimulation of vascular smooth muscle cell (VSMC) proliferation. Oxidized low density lipoprotein (oxLDL) is another important atherogenic factor that can increase VSMC proliferation. The purpose of this study was to investigate whether oxLDL could further enhance the proliferative action of mechanical stretch on VSMC, and to determine the mechanism responsible for this interaction. Because nuclear protein import is critical in regulating gene expression, transcription, and cell proliferation, its involvement in the mitogenic effects of oxLDL and mechanical stress was studied. OxLDL enhanced the proliferative effects of mechanical stretch on its own in rabbit aortic VSMC, and induced increases in the expression of HSP60 in an additive manner. Adenoviral-mediated overexpression of HSP60 induced increases in cell proliferation compared with uninfected VSMC. Mechanical stretch and oxLDL stimulated the rate of nuclear protein import in VSMC and increased the expression of nucleoporins. These effects were sensitive to inhibition of the MAPK pathway. We conclude that oxLDL and mechanical stretch have a synergistic effect on VSMC proliferation. This synergistic effect is induced through a stimulation of nuclear protein import via HSP60 and an activation of the MAPK pathway.

  16. Dectin-1 activation induces proliferation and migration of human keratinocytes enhancing wound re-epithelialization.

    PubMed

    van den Berg, Linda M; Zijlstra-Willems, Esther M; Richters, Cornelia D; Ulrich, Magda M W; Geijtenbeek, Teunis B H

    2014-01-01

    Beta-glucans in temporary wound dressings have immuno-stimulatory capacities and have been shown to enhance wound healing in burn patients. Curdlan is a 1,3-linked bacterial/fungal derived beta-glucan that induces inflammatory responses via the C-type lectin receptor dectin-1 on dendritic cells (DCs). Here we investigated the effect of beta-glucan curdlan and the role of dectin-1 expressed by keratinocytes (KCs) in wound healing. Curdlan enhanced migration, proliferation and wound closure of human KCs in a dectin-1 dependent manner, both in vitro and ex vivo. Our data suggest that curdlan induces human KC proliferation and migration and could therefore be used in creams to enhance wound healing.

  17. Class IIa Histone Deacetylases and Myocyte Enhancer Factor 2 Proteins Regulate the Mesenchymal-to-Epithelial Transition of Somatic Cell Reprogramming*

    PubMed Central

    Zhuang, Qiang; Qing, Xiaobing; Ying, Yue; Wu, Haitao; Benda, Christina; Lin, Jiao; Huang, Zhijian; Liu, Longqi; Xu, Yan; Bao, Xichen; Qin, Baoming; Pei, Duanqing; Esteban, Miguel A.

    2013-01-01

    Class IIa histone deacetylases (HDACs) and myocyte enhancer factor 2 (MEF2) proteins compose a signaling module that orchestrates lineage specification during embryogenesis. We show here that this module also regulates the generation of mouse induced pluripotent stem cells by defined transcription factors. Class IIa HDACs and MEF2 proteins rise steadily during fibroblast reprogramming to induced pluripotent stem cells. MEF2 proteins tend to block the process by inducing the expression of Tgfβ cytokines, which impairs the necessary phase of mesenchymal-to-epithelial transition (MET). Conversely, class IIa HDACs endeavor to suppress the activity of MEF2 proteins, thus enhancing the MET and colony formation efficiency. Our work highlights an unexpected role for a developmental axis in somatic cell reprogramming and provides new insight into how the MET is regulated in this context. PMID:23467414

  18. Myocyte enhancer factor 2D regulates ectoderm specification and adhesion properties of animal cap cells in the early Xenopus embryo.

    PubMed

    Katz Imberman, Sandra; Kolpakova, Alina; Keren, Aviad; Bengal, Eyal

    2015-08-01

    In Xenopus, animal cap (AC) cells give rise to ectoderm and its derivatives: epidermis and the central nervous system. Ectoderm has long been considered a default pathway of embryonic development, with cells that are not under the influence of vegetal Nodal signaling adopting an ectodermal program of gene expression. In the present study, we describe the involvement of the animally-localized maternal transcription factor myocyte enhancer factor (Mef) 2D in regulating the identity of AC cells. We find that Mef2D is required for the formation of both ectodermal lineages: neural and epidermis. Gain and loss of function experiments indicate that Mef2D regulates early gastrula expression of key ectodermal/epidermal genes in the animal region. Mef2D controls the activity of zygotic bone morphogenetic protein (BMP) signaling known to dictate the epidermal differentiation program. Exogenous expression of Mef2D in vegetal blastomeres was sufficient to induce ectopic expression of ectoderm/epidermal genes in the vegetal half of the embryo, when Nodal signaling was inhibited. Depletion of Mef2D caused a loss of AC cell adhesion that was rescued by the expression of E-cadherin or bone morphogenetic protein 4. In addition, expression of Mef2D in the prospective endoderm caused unusual aggregation of vegetal cells with animal cells in vitro and inappropriate segregation to other germ layers in vivo. Mef2D cooperates with another animally-expressed transcription factor, FoxI1e. Together, they regulate the expression of genes encoding signaling proteins and the transcription factors that control the regional identity of animal cells. Therefore, we describe a new role for the animally-localized Mef2D protein in early ectoderm specification, which is similar to that of the vegetally-localized VegT in endoderm and mesoderm formation.

  19. Fibroblast growth factor 2 retargeted adenovirus has redirected cellular tropism: evidence for reduced toxicity and enhanced antitumor activity in mice.

    PubMed

    Gu, D L; Gonzalez, A M; Printz, M A; Doukas, J; Ying, W; D'Andrea, M; Hoganson, D K; Curiel, D T; Douglas, J T; Sosnowski, B A; Baird, A; Aukerman, S L; Pierce, G F

    1999-06-01

    Adenovirus (Ad) have been used as vectors to deliver genes to a wide variety of tissues. Despite achieving high expression levels in vivo, Ad vectors display normal tissue toxicity, transient expression, and antivector immune responses that limit therapeutic potential. To circumvent these problems, several retargeting strategies to abrogate native tropism and redirect Ad uptake through defined receptors have been attempted. Despite success in cell culture, in vivo results have generally not shown sufficient selectivity for target tissues. We have previously identified (C. K. Goldman et al., Cancer Res., 57: 1447-1451, 1997) the fibroblast growth factor (FGF) ligand and receptor families as conferring sufficient specificity and binding affinity to be useful for targeting DNA in vivo. In the present studies, we retargeted Ad using basic FGF (FGF2) as a targeting ligand. Cellular uptake is redirected through high-affinity FGF receptors (FGFRs) and not the more ubiquitous lower-affinity Ad receptors. Initial in vitro experiments demonstrated a 10- to 100-fold increase in gene expression in numerous FGFR positive (FGFR+) cell lines using FGF2-Ad when compared with Ad. To determine whether increased selectivity could be detected in vivo, FGF2-Ad was administered i.v. to normal mice. FGF2-Ad demonstrates markedly decreased hepatic toxicity and liver transgene expression compared with Ad treatment. Importantly, FGF2-Ad encoding the herpes simplex virus thymidine kinase (TK) gene transduces Ad-resistant FGFR+ tumor cells both ex vivo and in vivo, which results in substantially enhanced survival (180-260%) when the prodrug ganciclovir is administered. Because FGFRs are up-regulated on many types of malignant or injured cells, this broadly useful method to redirect native Ad tropism and to increase the potency of gene expression may offer significant therapeutic advantages.

  20. Proliferation-Related Activity in Endothelial Cells Is Enhanced by Micropower Plasma

    PubMed Central

    Suzuki, Kotaro

    2016-01-01

    Nonthermal plasma has received a lot of attention as a medical treatment technique in recent years. It can easily create various reactive chemical species (ROS) and is harmless to living body. Although plasma at gas-liquid interface has a potential for a biomedical application, the interactions between the gas-liquid plasma and living cells remain unclear. Here, we show characteristics of a micropower plasma with 0.018 W of the power input, generated at gas-liquid interface. We also provide the evidence of plasma-induced enhancement in proliferation activity of endothelial cells. The plasma produced H2O2, HNO2, and HNO3 in phosphate buffered saline containing Mg++ and Ca++ (PBS(+)), and their concentration increased linearly during 600-second discharge. The value of pH in PBS(+) against the plasma discharge time was stable at about 7.0. Temperature in PBS(+) rose monotonically, and its rise was up to 0.8°C at the bottom of a cell-cultured dish by the plasma discharge for 600 s. Short-time treatment of the plasma enhanced proliferation activity of endothelial cells. In contrast, the treatment of H2O2 does not enhance the cell proliferation. Thus, the ROS production and the nuclear factor-kappa B (NF-κB) activation due to the plasma treatment might be related to enhancement of the cell proliferation. Our results may potentially provide the basis for developing the biomedical applications using the gas-liquid plasma. PMID:28058258

  1. Pleiotrophin enhances PDGFB-induced gliomagenesis through increased proliferation of neural progenitor cells

    PubMed Central

    Zhang, Lei; Laaniste, Liisi; Jiang, Yiwen; Alafuzoff, Irina; Uhrbom, Lene; Dimberg, Anna

    2016-01-01

    Pleiotrophin (PTN) augments tumor growth by increasing proliferation of tumor cells and promoting vascular abnormalization, but its role in early gliomagenesis has not been evaluated. Through analysis of publically available datasets, we demonstrate that increased PTN mRNA expression is associated with amplification of chromosome 7, identified as one of the earliest steps in glioblastoma development. To elucidate the role of PTN in tumor initiation we employed the RCAS/tv-a model that allows glioma induction by RCAS-virus mediated expression of oncogenes in neural progenitor cells. Intracranial injection of RCAS-PTN did not induce glioma formation when administrated alone, but significantly enhanced RCAS-platelet derived growth factor (PDGF)B-induced gliomagenesis. PTN co-treatment augmented PDGFB-induced Akt activation in neural progenitor cells in vitro, and enhanced neural sphere size associated with increased proliferation. Our data indicates that PTN expression is associated with chromosome 7 gain, and that PTN enhances PDGFB-induced gliomagenesis by stimulating proliferation of neural progenitor cells. PMID:27806344

  2. Pleiotrophin enhances PDGFB-induced gliomagenesis through increased proliferation of neural progenitor cells.

    PubMed

    Zhang, Lei; Laaniste, Liisi; Jiang, Yiwen; Alafuzoff, Irina; Uhrbom, Lene; Dimberg, Anna

    2016-12-06

    Pleiotrophin (PTN) augments tumor growth by increasing proliferation of tumor cells and promoting vascular abnormalization, but its role in early gliomagenesis has not been evaluated. Through analysis of publically available datasets, we demonstrate that increased PTN mRNA expression is associated with amplification of chromosome 7, identified as one of the earliest steps in glioblastoma development. To elucidate the role of PTN in tumor initiation we employed the RCAS/tv-a model that allows glioma induction by RCAS-virus mediated expression of oncogenes in neural progenitor cells. Intracranial injection of RCAS-PTN did not induce glioma formation when administrated alone, but significantly enhanced RCAS-platelet derived growth factor (PDGF)B-induced gliomagenesis. PTN co-treatment augmented PDGFB-induced Akt activation in neural progenitor cells in vitro, and enhanced neural sphere size associated with increased proliferation. Our data indicates that PTN expression is associated with chromosome 7 gain, and that PTN enhances PDGFB-induced gliomagenesis by stimulating proliferation of neural progenitor cells.

  3. Peptide-decorated chitosan derivatives enhance fibroblast adhesion and proliferation in wound healing.

    PubMed

    Patrulea, V; Hirt-Burri, N; Jeannerat, A; Applegate, L A; Ostafe, V; Jordan, O; Borchard, G

    2016-05-20

    RGD peptide sequences are known to regulate cellular activities by interacting with α5β1, αvβ5 and αvβ3 integrin, which contributes to the wound healing process. In this study, RGDC peptide was immobilized onto chitosan derivative 1,6-diaminohexane-O-carboxymethyl-N,N,N-trimethyl chitosan (DAH-CMTMC) to display RGDC-promoting adhesion for enhanced wound healing. The efficiency of N-methylation, O-carboxymethylation and spacer grafting was quantitatively and qualitatively analyzed by (1)H NMR and FTIR, yielding 0.38 degree of substitution for N-methylation and >0.85 for O-carboxymethylation. The glass transition temperatures for chitosan derivatives were also studied. Peptide immobilization was achieved through sulfhydryl groups using sulfosuccinimidyl (4-iodoacetyl)amino-benzoate (sulfo-SIAB method). RGDC immobilized peptide onto DAH-CMTMC was found to be about 15.3 μg/mg of chitosan derivative by amino acid analysis (AAA). The significant increase of human dermal fibroblast (HDF) viability in vitro over 7 days suggests that RGDC-functionalized chitosan may lead to enhanced wound healing (viability >140%). Moreover, bio-adhesion and proliferation assays confirmed that coatings of RGDC-functionalized chitosan derivatives exhibit in vitro wound healing properties by enhancing fibroblast proliferation and adhesion. These results showed that RGDC peptide-functionalized chitosan provides an optimal environment for fibroblast adhesion and proliferation.

  4. Linagliptin enhances neural stem cell proliferation after stroke in type 2 diabetic mice.

    PubMed

    Darsalia, Vladimer; Olverling, Anna; Larsson, Martin; Mansouri, Shiva; Nathanson, David; Nyström, Thomas; Klein, Thomas; Sjöholm, Åke; Patrone, Cesare

    2014-05-01

    Dipeptidyl peptidase 4 (DPP-4) inhibitors are current drugs for the treatment of type 2 diabetes (T2D) based on their main property to enhance endogenous glucagon-like peptide-1 (GLP-1) levels, thus increasing insulin secretion. However, the mechanism of action of DPP-4 inhibition in extra pancreatic tissues has been poorly investigated and it might occur differently from that induced by GLP-1R agonists. Increased adult neurogenesis by GLP-1R agonists has been suggested to play a role in functional recovery in animal models of brain disorders. We recently showed that the DPP-4 inhibitor linagliptin reduces brain damage after stroke in normal and type 2 diabetic (T2D) mice. The aim of this study was to determine whether linagliptin impacts stroke-induced neurogenesis. T2D was induced by 25 weeks of high-fat diet. Linagliptin treatment was carried out for 7 weeks. Standard diet fed-mice were used as controls. Stroke was induced by middle cerebral artery occlusion 4 weeks into the linagliptin treatment. Neural stem cell (NSC) proliferation/neuroblast formation and striatal neurogenesis/gliogenesis were assessed 3 weeks after stroke. The effect of linagliptin on NSC viability was also determined in vitro. The results show that linagliptin enhances NSC proliferation in T2D mice but not in normal mice. Linagliptin did not increase NSC number in vitro indicating that the effect of linagliptin on NSC proliferation in T2D is indirect. Neurogenesis and gliogenesis were not affected. In conclusion, we found no correlation between acute neuroprotection (occurring in both T2D and normal mice) and increased NSC proliferation (occurring only in T2D mice). However, our results show that linagliptin evokes a differential response on NSC proliferation after stroke in normal and T2D mice suggesting that DPP-4 inhibition effect in the CNS might go beyond the well known increase of GLP-1.

  5. Boiling Method-Based Zinc Oxide Nanorods for Enhancement of Adipose-Derived Stem Cell Proliferation.

    PubMed

    Jin, Su-Eon; Ahn, Hyo-Sun; Kim, Ji Hye; Arai, Yoshie; Lee, Soo-Hong; Yoon, Tae-Jong; Hwang, Sung-Joo; Sung, Jong-Hyuk

    2016-09-01

    Adipose-derived stem cells (ASCs) are typically expanded to acquire large numbers of cells for therapeutic applications. Diverse stimuli such as sphingosylphosphocholine and vitamin C have been used to increase the production yield and regenerative potential of ASCs. In the present study, we hypothesized that ZnO nanorods have promising potential for the enhancement of ASC proliferation. ZnO nanorods were prepared using three different methods: grinding and boiling at low temperature with and without surfactant. The physicochemical properties of the nanorods such as their crystallinity, morphology, size, and solvent compatibility were evaluated, and then, the ability of the synthesized ZnO nanorods to enhance ASC proliferation was investigated. Scanning electron microscopy images of all of the ZnO powders showed rod-shaped nanoflakes with lengths of 200-500 nm. Notably, although ZnO-G produced by the grinding method was well dispersed in ethanol, atomic force microscopy images of dispersions of both ZnO-B from boiling methods and ZnO-G indicated the presence of clusters of ZnO nanorods. In contrast, ZnO-B was freely dispersible in 5% dextrose of water and dimethyl sulfoxide, whereas ZnO-G and ZnO-M, produced by boiling with ethanolamine, were not. All three types of ZnO nanorods increased the proliferation of ASCs in a dose-dependent manner. These results collectively suggest that ZnO nanorods have promising potential for use as an agent for the enhancement of ASC proliferation.

  6. GMP-grade platelet lysate enhances proliferation and migration of tenon fibroblasts.

    PubMed

    Carducci, Augusto; Scafetta, Gaia; Siciliano, Camilla; Carnevale, Roberto; Rosa, Paolo; Coccia, Andrea; Mangino, Giorgio; Bordin, Antonella; Vingolo, Enzo Maria; Pierelli, Luca; Lendaro, Eugenio; Ragona, Giuseppe; Frati, Giacomo; De Falco, Elena

    2016-01-01

    Tenon's fibroblasts (TFs), widely employed as in vitro model for many ophthalmological studies, are routinely cultured with FBS. Platelet Lysate (PL), a hemoderivate enriched with growth factors and cytokines has been largely tested in several clinical applications and as substitute of FBS in culture. Here, we investigate whether PL can exert biological effects on TF populations similarly to other cell types. Results show that PL significantly enhances cell proliferation and migration vs. FBS, without influencing cell size/granularity. Upregulation of EGF, VEGF, KDR, MMP2-9, FAK mRNA levels also occurs and phosphorylation of AKT but not of ERK1/2 is significantly enhanced. The inhibition of the PI3kinase/AKT pathway with the specific inhibitor wortmannin, decreases PL-induced cell migration but not proliferation. Condition supernatants containing PL show increased bioavailability of Nitric Oxide and reduced levels of 8-Iso-PGF2-alpha, correlating with cell proliferation and migration. Pro-angiogenic/inflammatory soluble factors (GRO, Angiogenin, EGF, I-309, PARC) are exclusively or greater expressed in media containing PL than FBS. GMP-grade PL preparations positively influence in vitro biological effects of TFs representing a suitable and safer alternative to FBS.

  7. Enhanced proliferation, attachment and osteopontin expression by porcine periodontal cells exposed to Emdogain.

    PubMed

    Rincon, J C; Xiao, Y; Young, W G; Bartold, P M

    2005-12-01

    Emdogain (EMD) is an enamel matrix derivative extracted from developing porcine teeth with demonstrated periodontal regenerative potential. EMD has been shown to influence a number of properties of periodontal ligament cells including proliferation, cell attachment and matrix synthesis. To date, the effect of EMD on the epithelial cell rests of Malassez (ERM) is unknown. In this study, periodontal ligament fibroblasts, ERM, alveolar bone cells and gingival fibroblasts were obtained from porcine periodontal ligament, alveolar bone and gingiva. This study investigated, in vitro, the effect of EMD at three concentrations on proliferation, cell attachment and expression of mRNA for two mineralised tissue-related proteins (osteopontin and bone sialoprotein). As for other periodontal cells, the ERM proliferative response was enhanced by EMD. Attachment assays revealed a highly significant increase for ERM and gingival fibroblasts after EMD treatment at all concentrations. This study has also shown that EMD stimulated expression of osteopontin mRNA by ERM and alveolar bone cells. The results from this study provide evidence that EMD enhanced cellular events related with proliferation, attachment and osteopontin mRNA expression by porcine periodontal cells, in a manner consistent with its role in periodontal regenerative therapy.

  8. Statins enhance peroxisome proliferator-activated receptor gamma coactivator-1alpha activity to regulate energy metabolism.

    PubMed

    Wang, Wenxian; Wong, Chi-Wai

    2010-03-01

    Peroxisome proliferator-activated receptor gamma coactivator-1alpha (PGC-1alpha) serves as an inducible coactivator for a number of transcription factors to control energy metabolism. Insulin signaling through Akt kinase has been demonstrated to phosphorylate PGC-1alpha at serine 571 and downregulate its activity in the liver. Statins are 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors that reduce cholesterol synthesis in the liver. In this study, we found that statins reduced the active form of Akt and enhanced PGC-1alpha activity. Specifically, statins failed to activate an S571A mutant of PGC-1alpha. The activation of PGC-1alpha by statins selectively enhanced the expression of energy metabolizing enzymes and regulators including peroxisome proliferator-activated receptor alpha, acyl-CoA oxidase, carnitine palmitoyl transferase-1A, and pyruvate dehydrogenase kinase 4. Importantly, a constitutively active form of Akt partially reduced the statin-enhanced gene expression. Our study thus provides a plausible mechanistic explanation for the hypolipidemic effect of statin through elevating the rate of beta-oxidation and mitochondrial Kreb's cycle capacity to enhance fatty acid utilization while reducing the rate of glycolysis.

  9. In vitro electromagnetic stimulation to enhance cell proliferation in extracellular matrix constructs with and without metallic nanoparticles.

    PubMed

    Grant, Daniel N; Cozad, Matthew J; Grant, David A; White, Richard A; Grant, Sheila A

    2015-11-01

    Extremely low frequency electromagnetic fields (ELF-EMFs) can induce beneficial effects including enhanced protein synthesis and cell proliferation on healing bone and skin wounds. This study investigated the effects of ELF-EMFs on acellular tissue constructs with and without gold nanoparticles (AuNPs) to determine if cell proliferation could be increase and thus provide an enhanced mechanism for in vitro cell seeding on tissue engineered constructs. Different sized AuNPs, 20 and 100 nm, were conjugated to acellular porcine tissue, seeded with L929 murine fibroblasts and exposed to a continuous 12 gauss, 60 Hz electromagnetic field for 2 hours each day up to 10 days. Scanning electron microscopy and cell culture assays were performed to ascertain cell proliferation and viability before and after exposure. Results indicate the ELF-EMF stimulation significantly increased cell proliferation. The presence of AuNPs did not boost the stimulatory effects, but they did demonstrated higher rates of proliferation from day 3 to day 10. In addition, unstimulated 100 nm AuNPs constructs resulted in significant increases in proliferation as compared to unstimulated crosslinked constructs. In conclusion, ELF-EMF stimulation enhanced cellular proliferation and while the presence of AuNPs did not significantly enhance this effect, AuNPs resulted in increased proliferation rates from day 3 to day 10.

  10. Dopamine Receptor Antagonists Enhance Proliferation and Neurogenesis of Midbrain Lmx1a-expressing Progenitors.

    PubMed

    Hedlund, Eva; Belnoue, Laure; Theofilopoulos, Spyridon; Salto, Carmen; Bye, Chris; Parish, Clare; Deng, Qiaolin; Kadkhodaei, Banafsheh; Ericson, Johan; Arenas, Ernest; Perlmann, Thomas; Simon, András

    2016-06-01

    Degeneration of dopamine neurons in the midbrain causes symptoms of the movement disorder, Parkinson disease. Dopamine neurons are generated from proliferating progenitor cells localized in the embryonic ventral midbrain. However, it remains unclear for how long cells with dopamine progenitor character are retained and if there is any potential for reactivation of such cells after cessation of normal dopamine neurogenesis. We show here that cells expressing Lmx1a and other progenitor markers remain in the midbrain aqueductal zone beyond the major dopamine neurogenic period. These cells express dopamine receptors, are located in regions heavily innervated by midbrain dopamine fibres and their proliferation can be stimulated by antagonizing dopamine receptors, ultimately leading to increased neurogenesis in vivo. Furthermore, treatment with dopamine receptor antagonists enhances neurogenesis in vitro, both from embryonic midbrain progenitors as well as from embryonic stem cells. Altogether our results indicate a potential for reactivation of resident midbrain cells with dopamine progenitor potential beyond the normal period of dopamine neurogenesis.

  11. Identification of singles bar as a direct transcriptional target of Drosophila Myocyte enhancer factor-2 and a regulator of adult myoblast fusion.

    PubMed

    Brunetti, Tonya M; Fremin, Brayon J; Cripps, Richard M

    2015-05-15

    In Drosophila, myoblast fusion is a conserved process in which founder cells (FCs) and fusion competent myoblasts (FCMs) fuse to form a syncytial muscle fiber. Mutants for the myogenic regulator Myocyte enhancer factor-2 (MEF2) show a failure of myoblast fusion, indicating that MEF2 regulates the fusion process. Indeed, chromatin immunoprecipitation studies show that several genes involved in myoblast fusion are bound by MEF2 during embryogenesis. Of these, the MARVEL domain gene singles bar (sing), is down-regulated in MEF2 knockdown pupae, and has five consensus MEF2 binding sites within a 9000-bp region. To determine if MEF2 is an essential and direct regulator of sing during pupal muscle development, we identified a 315-bp myoblast enhancer of sing. This enhancer was active during myoblast fusion, and mutation of two MEF2 sites significantly decreased enhancer activity. We show that lack of sing expression resulted in adult lethality and muscle loss, due to a failure of fusion during the pupal stage. Additionally, we sought to determine if sing was required in either FCs or FCMs to support fusion. Interestingly, knockdown of sing in either population did not significantly affect fusion, however, knockdown in both FCs and FCMs resulted in muscles with significantly reduced nuclei numbers, provisionally indicating that sing function is required in either cell type, but not both. Finally, we found that MEF2 regulated sing expression at the embryonic stage through the same 315-bp enhancer, indicating that sing is a MEF2 target at both critical stages of myoblast fusion. Our studies define for the first time how MEF2 directly controls fusion at multiple stages of the life cycle, and provide further evidence that the mechanisms of fusion characterized in Drosophila embryos is also used in the formation of the more complex adult muscles.

  12. Hypoxia-induced mitogenic factor enhances angiogenesis by promoting proliferation and migration of endothelial cells

    SciTech Connect

    Tong Qiangsong; Zheng Liduan; Li Bo; Wang Danming; Huang Chuanshu; Matuschak, George M.; Li Dechun . E-mail: dli2@slu.edu

    2006-11-01

    Our previous studies have indicated that hypoxia-induced mitogenic factor (HIMF) has angiogenic properties in an in vivo matrigel plug model and HIMF upregulates expression of vascular endothelial growth factor (VEGF) in mouse lungs and cultured lung epithelial cells. However, whether HIMF exerts angiogenic effects through modulating endothelial cell function remains unknown. In this study, mouse aortic rings cultured with recombinant HIMF protein resulted in enhanced vascular sprouting and increased endothelial cell spreading as confirmed by Dil-Ac-LDL uptake, von Willebrand factor and CD31 staining. In cultured mouse endothelial cell line SVEC 4-10, HIMF dose-dependently enhanced cell proliferation, in vitro migration and tubulogenesis, which was not attenuated by SU1498, a VEGFR2/Flk-1 receptor tyrosine kinase inhibitor. Moreover, HIMF stimulation resulted in phosphorylation of Akt, p38 and ERK1/2 kinases in SVEC 4-10 cells. Treatment of mouse aortic rings and SVEC 4-10 cells with LY294002, but not SB203580, PD098059 or U0126, abolished HIMF-induced vascular sprouting and angiogenic responses. In addition, transfection of a dominant-negative mutant of phosphatidylinositol 3-kinase (PI-3K), {delta}p85, blocked HIMF-induced phosphorylation of Akt, endothelial activation and tubulogenesis. These results indicate that HIMF enhances angiogenesis by promoting proliferation and migration of endothelial cells via activation of the PI-3K/Akt pathways.

  13. Platelet Lysate-Modified Porous Silicon Microparticles for Enhanced Cell Proliferation in Wound Healing Applications.

    PubMed

    Fontana, Flavia; Mori, Michela; Riva, Federica; Mäkilä, Ermei; Liu, Dongfei; Salonen, Jarno; Nicoletti, Giovanni; Hirvonen, Jouni; Caramella, Carla; Santos, Hélder A

    2016-01-13

    The new frontier in the treatment of chronic nonhealing wounds is the use of micro- and nanoparticles to deliver drugs or growth factors into the wound. Here, we used platelet lysate (PL), a hemoderivative of platelets, consisting of a multifactorial cocktail of growth factors, to modify porous silicon (PSi) microparticles and assessed both in vitro and ex vivo the properties of the developed microsystem. PL-modified PSi was assessed for its potential to induce proliferation of fibroblasts. The wound closure-promoting properties of the microsystem were then assessed in an in vitro wound healing assay. Finally, the PL-modified PSi microparticles were evaluated in an ex vivo experiment over human skin. It was shown that PL-modified PSi microparticles were cytocompatible and enhanced the cell proliferation in different experimental settings. In addition, this microsystem promoted the closure of the gap between the fibroblast cells in the wound healing assay, in periods of time comparable with the positive control, and induced a proliferation and regeneration process onto the human skin in an ex vivo experiment. Overall, our results show that PL-modified PSi microparticles are suitable microsystems for further development toward applications in the treatment of chronic nonhealing wounds.

  14. Canonical Wnt signaling transiently stimulates proliferation and enhances neurogenesis in neonatal neural progenitor cultures

    SciTech Connect

    Hirsch, Cordula; Campano, Louise M.; Woehrle, Simon; Hecht, Andreas . E-mail: andreas.hecht@mol-med.uni-freiburg.de

    2007-02-01

    Canonical Wnt signaling triggers the formation of heterodimeric transcription factor complexes consisting of {beta}-catenin and T cell factors, and thereby controls the execution of specific genetic programs. During the expansion and neurogenic phases of embryonic neural development canonical Wnt signaling initially controls proliferation of neural progenitor cells, and later neuronal differentiation. Whether Wnt growth factors affect neural progenitor cells postnatally is not known. Therefore, we have analyzed the impact of Wnt signaling on neural progenitors isolated from cerebral cortices of newborn mice. Expression profiling of pathway components revealed that these cells are fully equipped to respond to Wnt signals. However, Wnt pathway activation affected only a subset of neonatal progenitors and elicited a limited increase in proliferation and neuronal differentiation in distinct subsets of cells. Moreover, Wnt pathway activation only transiently stimulated S-phase entry but did not support long-term proliferation of progenitor cultures. The dampened nature of the Wnt response correlates with the predominant expression of inhibitory pathway components and the rapid actuation of negative feedback mechanisms. Interestingly, in differentiating cell cultures activation of canonical Wnt signaling reduced Hes1 and Hes5 expression suggesting that during postnatal neural development, Wnt/{beta}-catenin signaling enhances neurogenesis from progenitor cells by interfering with Notch pathway activity.

  15. Mesenchymal stem cells growth and proliferation enhancement using PLA vs PCL based nanofibrous scaffolds.

    PubMed

    Marei, Narguess H; El-Sherbiny, Ibrahim M; Lotfy, Ahmed; El-Badawy, Ahmed; El-Badri, Nagwa

    2016-12-01

    Electrospinning of polymers is the most commonly used technique for nanofiber fabrication. polylactic acid (PLA) and polycaprolactone (PCL) have been shown to be ideal for nanofiber preparation in various biomedical applications, due to characteristics such as biodegradablity and their ability to promote the cell growth, similar to native tissues. The aim of this study was to develop biocompatible and biodegradable PLA and PCL-based nanofibrous scaffolds for enhancing stem cell growth and proliferation. The scaffolds were prepared by electrospinning, and their physicochemical properties were studied using Fourier Transform Infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and X-ray diffraction (XRD). The surface morphology of the developed scaffolds was determined using scanning electron microscopy (SEM). Mesenchymal stem cells (MSCs), derived from both adipose tissue and bone marrow, were seeded onto the prepared nanofibrous scaffolds. The effect of scaffold type, and structural characteristics on survival and proliferation of MSCs were evaluated. Our results show that after full physicochemical characterization of PCL and PLA nanofibrous scaffolds both were safe and non-toxic to the evaluated cells and both scaffolds supported cell attachment and proliferation of bone marrow and adipose tissue-derived MSCs.

  16. Epigenetic inhibition of miR-663b by long non-coding RNA HOTAIR promotes pancreatic cancer cell proliferation via up-regulation of insulin-like growth factor 2

    PubMed Central

    Chen, Xuemin; Sun, Donglin; Chen, Tongbing; Peng, Yan; Zhu, Feng; Jiang, Yong; He, Xiaozhou

    2016-01-01

    Pancreatic cancer is one of the most deadly cancers with a poor prognosis. Although microRNAs are involving in the carcinogenesis and development of pancreatic cancer, little information is known regarding the role of miR-663b in pancreatic cancer. In this study, the expression of miR-663b in pancreatic cancer cells was down-regulated by hypermethylation in its putative promoter region, and overexpression of miR-663b repressed cell proliferation, invasion and migration, and induced apoptosis in pancreatic cancer cells. Bioinformatics analysis, luciferase report assay and rescue experiments showed that insulin-like growth factor 2 (IGF2) was a direct target of miR-663b. Results from clinical samples showed that the expression level of miR-663b correlated with the pathological grading, and the expression of miR-663b was down-regulated and was inversely correlated with IGF2 expression level in pancreatic cancer tissues. More importantly, the long non-coding RNA, HOX transcript antisense RNA (HOTAIR), was up-regulated in both pancreatic cancer cells and tissues, and HOTAIR suppressed the expression of miR-663b in pancreatic cancer by histone modification on H3K4me3 and H3K27me3 on miR-663b promoter. Further in vivo studies demonstrated that the stable overexpression of miR-663b or knock-down of HOTAIR inhibited tumor growth and was associated with IGF2 expression. In summary, our studies demonstrated that miR-663b is epigenetically repressed by HOTAIR and exerts its tumor-suppressive function via targeting IGF2 in pancreatic cancer. PMID:27895308

  17. Both core and F proteins of hepatitis C virus could enhance cell proliferation in transgenic mice

    SciTech Connect

    Hu, Wen-Ta; Li, Hui-Chun; Lee, Shen-Kao; Ma, Hsin-Chieh; Yang, Chee-Hing; Chen, Hung-Ling; Lo, Shih-Yen

    2013-05-24

    Highlights: •HCV core and F proteins could induce hepatocyte proliferation in the transgenic mice. •β-Catenin signaling pathway was activated by core protein in the transgenic mice. •β-Catenin signaling pathway was activated by myc-F protein in the transgenic mice. •Expression of SMA protein was enhanced by core but not myc-F protein. -- Abstract: The role of the protein encoded by the alternative open reading frame (ARF/F/core+1) of the Hepatitis C virus (HCV) genome in viral pathogenesis remains unknown. The different forms of ARF/F/core+1 protein were labile in cultured cells, a myc-tag fused at the N-terminus of the F protein made it more stable. To determine the role of core and F proteins in HCV pathogenesis, transgenic mice with either protein expression under the control of Albumin promoter were generated. Expression of core protein and F protein with myc tag (myc-F) could be detected by Western blotting analysis in the livers of these mice. The ratio of liver to body weight is increased for both core and myc-F transgenic mice compared to that of wild type mice. Indeed, the proliferating cell nuclear antigen protein, a proliferation marker, was up-regulated in the transgenic mice with core or myc-F protein. Further analyses by microarray and Western blotting suggested that β-catenin signaling pathway was activated by either core or myc-F protein in the transgenic mice. These transgenic mice were further treated with either Diethynitrosamine (a tumor initiator) or Phenobarbital (a tumor promoter). Phenobarbital but not Diethynitrosamine treatment could increase the liver/body weight ratio of these mice. However, no tumor formation was observed in these mice. In conclusion, HCV core and myc-F proteins could induce hepatocyte proliferation in the transgenic mice possibly through β-catenin signaling pathway.

  18. In vivo but not in vitro leptin enhances lymphocyte proliferation in Siberian hamsters (Phodopus sungorus).

    PubMed

    Demas, Gregory E

    2010-04-01

    Mounting an immune response requires a relatively substantial investment of energy and marked reductions in energy availability can suppress immune function and presumably increase disease susceptibility. We have previously demonstrated that a moderate reduction in energy stores by partial surgical lipectomy impairs humoral immunity of Siberian hamsters (Phodopus sungorus) and is mediated, in part, by changes in the adipose tissue hormone leptin. The goals of the present study were to assess the role of leptin in cell-mediated immunity and to determine if the potential effects of leptin on immunity are via the direct actions of this hormone on lymphocytes, or indirect, via the sympathetic nervous system (SNS). In Experiment 1, hamsters received osmotic minipumps containing either murine leptin (0.5 microl/h) or vehicle alone for 10 days and splenocyte proliferation in response to the T-cell mitogen Concanavalin A (Con A) was determined. In Experiment 2, Con A-induced splenocyte proliferation was tested in the presence or absence of leptin in vitro. In Experiment 3, exogenous leptin was administered to intact or sympathetically denervated hamsters. Hamsters treated with in vivo leptin displayed increased splenocyte proliferation compared with control hamsters receiving vehicle. In contrast, in vitro leptin had no effect on splenocyte proliferation. Sympathetic denervation attenuated, but did not block, leptin-induced increases in immunity. Taken together, these results are consistent with the idea that leptin can enhance cell-mediated immunity; the SNS appears to contribute, least in part, to leptin-induced increases in immunity. Importantly, these findings confirm previous studies that leptin serves as an important endocrine link between energy balance and immunity.

  19. Proliferation and motility of HaCaT keratinocyte derivatives is enhanced by fibroblast nemosis

    SciTech Connect

    Raesaenen, Kati; Vaheri, Antti

    2010-06-10

    The role of paracrine tumor-stroma regulation in the progression of cancer is under intense investigation. Activated fibroblasts are key components of the tumor microenvironment providing the soluble factors mediating the regulation. Nemosis is an experimental model to study these parameters: formation of a multicellular spheroid activates fibroblasts and leads to increased production of soluble factors involved in the promotion of growth and motility. Role of nemosis was investigated in the tumorigenesis of HaCaT derivatives representing skin carcinoma progression. Conditioned medium from fibroblast spheroids increased proliferation rate of HaCaT derivatives. Expression of proliferation marker Ki-67 increased significantly in benign A5 and low-grade malignant II-4 cells, but did not further increase in the metastatic RT3 cells. Expression of p63, keratinocyte stem cell marker linked to cancer progression, was augmented by medium from nemotic fibroblasts; this increase was also seen in RT3 cells. Scratch-wound healing of the keratinocytes was enhanced in response to fibroblast nemosis. Neutralizing antibodies against growth factors inhibited wound healing to some extent; the response varied between benign and malignant keratinocytes. Migration and invasion were enhanced by conditioned medium from nemotic fibroblasts in benign and low-grade malignant cells. RT3 keratinocyte migration was further augmented, but invasion was not, indicating their intrinsic capacity to invade. Our data demonstrate that fibroblast nemosis increases proliferation and motility of HaCaT keratinocyte derivatives, and thus nemosis can be used as a model to study the role of soluble factors secreted by fibroblasts in tumor progression.

  20. Titanium phosphate glass microcarriers induce enhanced osteogenic cell proliferation and human mesenchymal stem cell protein expression

    PubMed Central

    Lakhkar, Nilay J; M Day, Richard; Kim, Hae-Won; Ludka, Katarzyna; Mordan, Nicola J; Salih, Vehid; Knowles, Jonathan C

    2015-01-01

    In this study, we have developed 50- to 100-µm-sized titanium phosphate glass microcarriers (denoted as Ti5) that show enhanced proliferation of human mesenchymal stem cells and MG63 osteosarcoma cells, as well as enhanced human mesenchymal stem cell expression of bone differentiation markers, in comparison with commercially available glass microspheres at all time points. We also demonstrate that these microcarriers provide superior human mesenchymal stem cell proliferation with conventional Dulbecco’s Modified Eagle medium than with a specially developed commercial stem cell medium. The microcarrier proliferative capacity is revealed by a 24-fold increase in MG63 cell numbers in spinner flask bioreactor studies performed over a 7-day period, versus only a 6-fold increase in control microspheres under the same conditions; the corresponding values of Ti5 and control microspheres under static culture are 8-fold and 7-fold, respectively. The capability of guided osteogenic differentiation is confirmed by ELISAs for bone morphogenetic protein-2 and osteopontin, which reveal significantly greater expression of these markers, especially osteopontin, by human mesenchymal stem cells on the Ti5 microspheres than on the control. Scanning electron microscopy and confocal laser scanning microscopy images reveal favorable MG63 and human mesenchymal stem cell adhesion on the Ti5 microsphere surfaces. Thus, the results demonstrate the suitability of the developed microspheres for use as microcarriers in bone tissue engineering applications. PMID:26668711

  1. Interactions between mitochondria and the transcription factor myocyte enhancer factor 2 (MEF2) regulate neuronal structural and functional plasticity and metaplasticity

    PubMed Central

    Brusco, Janaina; Haas, Kurt

    2015-01-01

    The classical view of mitochondria as housekeeping organelles acting in the background to simply maintain cellular energy demands has been challenged by mounting evidence of their direct and active participation in synaptic plasticity in neurons. Time-lapse imaging has revealed that mitochondria are motile in dendrites, with their localization and fusion and fission events regulated by synaptic activity. The positioning of mitochondria directly influences function of nearby synapses through multiple pathways including control over local concentrations of ATP, Ca2+ and reactive oxygen species. Recent studies have also shown that mitochondrial protein cascades, classically associated with apoptosis, are involved in neural plasticity in healthy cells. These findings link mitochondria to the plasticity- and metaplasticity-associated activity-dependent transcription factor myocyte enhancer factor 2 (MEF2), further repositioning mitochondria as potential command centres for regulation of synaptic plasticity. Intriguingly, MEF2 and mitochondrial functions appear to be intricately intertwined, as MEF2 is a target of mitochondrial apoptotic caspases and, in turn, MEF2 regulates mitochondrial genome transcription essential for production of superoxidase and hydrogen peroxidase. Here, we review evidence supporting mitochondria as central organelles controlling the spatiotemporal expression of neuronal plasticity, and attempt to disentangle the MEF2–mitochondria relationship mediating these functions. PMID:25581818

  2. Promotion of glucose utilization by insulin enhances granulosa cell proliferation and developmental competence of porcine oocyte grown in vitro.

    PubMed

    Itami, Nobuhiko; Munakata, Yasuhisa; Shirasuna, Koumei; Kuwayama, Takehito; Iwata, Hisataka

    2017-02-01

    In vitro culture of the oocyte granulosa cell complexes (OGCs) from early antral follicles (EAFs) shows granulosa cell (GC) proliferation, but to a lesser extent than that observed in vivo during follicle development. As the number of GCs closely relates to energy sufficiency of the oocytes, enhancement of GC proliferation influences oocyte development. GC proliferation depends on glycolysis and insulin-mediated AKT/mTOR signaling pathway; therefore, addition of culture medium containing insulin and glucose may potentially promote GC proliferation and hence improve oocyte development. In the present study, we assessed the effect of exogenous insulin and glucose concentration on GC proliferation and oocyte energy status as well as developmental abilities of porcine oocytes grown in vitro. In the presence of 5.5 mM of glucose (Low), a comparison of 10 versus 20 μg/ml insulin showed that high insulin enhanced GC proliferation but exhausted glucose from the medium, which resulted in low energy status including lipid and adenosine triphosphate of the oocyte. Whereas, in the presence of 20 μg/ml insulin, medium with 11 mM glucose (High) enhanced GC proliferation and oocyte energy status as well as developmental ability up to the blastocyst stage. Considering that there was no difference in OGCs development observed with medium (10 μg/ml insulin) containing 5.5 versus 11 mM glucose, we concluded that the combination of high insulin and glucose enhanced GC proliferation and energy status of oocytes as well as the developmental ability of the oocytes grown in vitro.

  3. Dopamine Receptor Antagonists Enhance Proliferation and Neurogenesis of Midbrain Lmx1a-expressing Progenitors

    PubMed Central

    Hedlund, Eva; Belnoue, Laure; Theofilopoulos, Spyridon; Salto, Carmen; Bye, Chris; Parish, Clare; Deng, Qiaolin; Kadkhodaei, Banafsheh; Ericson, Johan; Arenas, Ernest; Perlmann, Thomas; Simon, András

    2016-01-01

    Degeneration of dopamine neurons in the midbrain causes symptoms of the movement disorder, Parkinson disease. Dopamine neurons are generated from proliferating progenitor cells localized in the embryonic ventral midbrain. However, it remains unclear for how long cells with dopamine progenitor character are retained and if there is any potential for reactivation of such cells after cessation of normal dopamine neurogenesis. We show here that cells expressing Lmx1a and other progenitor markers remain in the midbrain aqueductal zone beyond the major dopamine neurogenic period. These cells express dopamine receptors, are located in regions heavily innervated by midbrain dopamine fibres and their proliferation can be stimulated by antagonizing dopamine receptors, ultimately leading to increased neurogenesis in vivo. Furthermore, treatment with dopamine receptor antagonists enhances neurogenesis in vitro, both from embryonic midbrain progenitors as well as from embryonic stem cells. Altogether our results indicate a potential for reactivation of resident midbrain cells with dopamine progenitor potential beyond the normal period of dopamine neurogenesis. PMID:27246266

  4. Discovery of Novel Small Molecules that Activate Satellite Cell Proliferation and Enhance Repair of Damaged Muscle.

    PubMed

    Billin, Andrew N; Bantscheff, Marcus; Drewes, Gerard; Ghidelli-Disse, Sonja; Holt, Jason A; Kramer, Henning F; McDougal, Alan J; Smalley, Terry L; Wells, Carrow I; Zuercher, William J; Henke, Brad R

    2016-02-19

    Skeletal muscle progenitor stem cells (referred to as satellite cells) represent the primary pool of stem cells in adult skeletal muscle responsible for the generation of new skeletal muscle in response to injury. Satellite cells derived from aged muscle display a significant reduction in regenerative capacity to form functional muscle. This decrease in functional recovery has been attributed to a decrease in proliferative capacity of satellite cells. Hence, agents that enhance the proliferative abilities of satellite cells may hold promise as therapies for a variety of pathological settings, including repair of injured muscle and age- or disease-associated muscle wasting. Through phenotypic screening of isolated murine satellite cells, we identified a series of 2,4-diaminopyrimidines (e.g., 2) that increased satellite cell proliferation. Importantly, compound 2 was effective in accelerating repair of damaged skeletal muscle in an in vivo mouse model of skeletal muscle injury. While these compounds were originally prepared as c-Jun N-terminal kinase 1 (JNK-1) inhibitors, structure-activity analyses indicated JNK-1 inhibition does not correlate with satellite cell activity. Screening against a broad panel of kinases did not result in identification of an obvious molecular target, so we conducted cell-based proteomics experiments in an attempt to identify the molecular target(s) responsible for the potentiation of the satellite cell proliferation. These data provide the foundation for future efforts to design improved small molecules as potential therapeutics for muscle repair and regeneration.

  5. Utility of Social Modeling for Proliferation Assessment - Enhancing a Facility-Level Model for Proliferation Resistance Assessment of a Nuclear Enegry System

    SciTech Connect

    Coles, Garill A.; Brothers, Alan J.; Gastelum, Zoe N.; Olson, Jarrod; Thompson, Sandra E.

    2009-10-26

    The Utility of Social Modeling for Proliferation Assessment project (PL09-UtilSocial) investigates the use of social and cultural information to improve nuclear proliferation assessments, including nonproliferation assessments, Proliferation Resistance (PR) assessments, safeguards assessments, and other related studies. These assessments often use and create technical information about a host State and its posture towards proliferation, the vulnerability of a nuclear energy system (NES) to an undesired event, and the effectiveness of safeguards. This objective of this project is to find and integrate social and technical information by explicitly considering the role of cultural, social, and behavioral factors relevant to proliferation; and to describe and demonstrate if and how social science modeling has utility in proliferation assessment. This report describes a modeling approach and how it might be used to support a location-specific assessment of the PR assessment of a particular NES. The report demonstrates the use of social modeling to enhance an existing assessment process that relies on primarily technical factors. This effort builds on a literature review and preliminary assessment performed as the first stage of the project and compiled in PNNL-18438. [ T his report describes an effort to answer questions about whether it is possible to incorporate social modeling into a PR assessment in such a way that we can determine the effects of social factors on a primarily technical assessment. This report provides: 1. background information about relevant social factors literature; 2. background information about a particular PR assessment approach relevant to this particular demonstration; 3. a discussion of social modeling undertaken to find and characterize social factors that are relevant to the PR assessment of a nuclear facility in a specific location; 4. description of an enhancement concept that integrates social factors into an existing, technically

  6. Osterix enhances proliferation and osteogenic potential of bone marrow stromal cells

    SciTech Connect

    Tu Qisheng; Valverde, Paloma . E-mail: paloma.valverde@tufts.edu; Chen, Jake

    2006-03-24

    Osterix (Osx) is a zinc-finger-containing transcription factor that is expressed in osteoblasts of all endochondral and membranous bones. In Osx null mice osteoblast differentiation is impaired and bone formation is absent. In this study, we hypothesized that overexpression of Osx in murine bone marrow stromal cells (BMSC) would be able to enhance their osteoblastic differentiation and mineralization in vitro. Retroviral transduction of Osx in BMSC cultured in non-differentiating medium did not affect expression of Runx2/Cbfa1, another key transcription factor of osteoblast differentiation, but induced an increase in the expression of other markers associated with the osteoblastic lineage including alkaline phosphatase, bone sialoprotein, osteocalcin, and osteopontin. Retroviral transduction of Osx in BMSC also increased their proliferation, alkaline phosphatase activity, and ability to form bone nodules. These events occurred without significant changes in the expression of {alpha}1(II) procollagen or lipoprotein lipase, which are markers of chondrogenic and adipogenic differentiation, respectively.

  7. FBI-1 enhances ETS-1 signaling activity and promotes proliferation of human colorectal carcinoma cells.

    PubMed

    Zhu, Min; Li, Mingyang; Zhang, Fan; Feng, Fan; Chen, Weihao; Yang, Yutao; Cui, Jiajun; Zhang, Dong; Linghu, Enqiang

    2014-01-01

    In this study, we investigated a potential regulatory role of FBI-1 in transcription factor activity of ETS-1. The protein interaction was identified between ETS-1 and FBI-1 in lovo cells. The accumulating data showed that FBI-1 promoted the recruitment of ETS-1 to endogenous promoter of its target genes and increase ETS-1 accumulation in the nuclear. Our work also indicated that the FBI-1 enhances ETS-1 transcription factor activity via down-regulating p53-mediated inhibition on ETS-1. Further, FBI-1 plays a role in regulation of colorectal carcinoma cells proliferation. These findings supported that FBI-1 might be a potential molecule target for treating colorectal carcinoma.

  8. Three-dimensional polycaprolactone hierarchical scaffolds supplemented with natural biomaterials to enhance mesenchymal stem cell proliferation.

    PubMed

    Yoon, Hyeon; Ahn, Seunghyun; Kim, Geunhyung

    2009-10-01

    A hybrid technology that combines a three-dimensional (3-D) dispensing system with an electrospinning process was used to produce a hierarchical 3-D scaffold consisting of micro-sized polycaprolactone (PCL) strands and micro/nano-sized fibres. The micro/nanofibre biocomposites electrospun with PCL/small intestine submucosa (SIS) and PCL/Silk fibroin were layered between melt-plotted micro-strands. The scaffold containing SIS exhibited a stronger hydrophilic property than other scaffolds due to the various hydrophilic components in SIS. The 3-D hierarchical scaffold having biocomposites exhibited an incredibly enhanced initial cell attachment and proliferation of bone marrow-derived mesenchymal stem cells relative to the normally designed 3-D scaffold.

  9. FBI-1 Enhances ETS-1 Signaling Activity and Promotes Proliferation of Human Colorectal Carcinoma Cells

    PubMed Central

    Chen, Weihao; Yang, Yutao; Cui, Jiajun; Zhang, Dong; Linghu, Enqiang

    2014-01-01

    In this study, we investigated a potential regulatory role of FBI-1 in transcription factor activity of ETS-1. The protein interaction was identified between ETS-1 and FBI-1 in lovo cells. The accumulating data showed that FBI-1 promoted the recruitment of ETS-1 to endogenous promoter of its target genes and increase ETS-1 accumulation in the nuclear. Our work also indicated that the FBI-1 enhances ETS-1 transcription factor activity via down-regulating p53-mediated inhibition on ETS-1. Further, FBI-1 plays a role in regulation of colorectal carcinoma cells proliferation. These findings supported that FBI-1 might be a potential molecule target for treating colorectal carcinoma. PMID:24857950

  10. Acetylation Enhances the Promoting Role of AIB1 in Breast Cancer Cell Proliferation

    PubMed Central

    You, Dingyun; Zhao, Hongbo; Wang, Yan; Jiao, Yang; Lu, Minnan; Yan, Shan

    2016-01-01

    The oncogene nuclear receptor coactivator amplified in breast cancer 1 (AIB1) is a transcriptional coactivator, which is overexpressed in various types of human cancers, including breast cancer. However, the molecular mechanisms regulating AIB1 function remain largely unknown. In this study, we present evidence demonstrating that AIB1 is acetylated by MOF in human breast cancer cells. Moreover, we also found that the acetylation of AIB1 enhances its function in promoting breast cancer cell proliferation. We further showed that the acetylation of AIB1 is required for its recruitment to E2F1 target genes by E2F1. More importantly, we found that the acetylation levels of AIB1 are greatly elevated in human breast cancer cells compared with that in non-cancerous cells. Collectively, our results shed light on the molecular mechanisms that regulate AIB1 function in breast cancer. PMID:27665502

  11. GPR171 expression enhances proliferation and metastasis of lung cancer cells.

    PubMed

    Dho, So Hee; Lee, Kwang-Pyo; Jeong, Dongjun; Kim, Chang-Jin; Chung, Kyung-Sook; Kim, Ji Young; Park, Bum-Chan; Park, Sung Sup; Kim, Seon-Young; Kwon, Ki-Sun

    2016-02-16

    G protein-coupled receptors (GPCRs) are among the most significant therapeutic targets and some of them promote the growth and metastasis of cancer. Here, we show that an increase in the levels of GPR171 is crucial for lung cancer tumor progression in vitro and in vivo. Immunostaining of clinical samples indicated that GPR171 was overexpressed in 46.8% of lung carcinoma tissues. Depletion of GPR171 with an anti-GPR171 antibody decreased proliferation of lung carcinoma cells and attenuated tumor progression in a mouse xenograft model. Knockdown of GPR171 also inhibited migration and invasion of the lung cancer cell lines. Notably, inhibition of GPR171 synergistically enhanced the tumoricidal activity of an epidermal growth factor receptor (EGFR) inhibitor in lung cancer cells. These results indicate that GPR171 blockade is a promising antineoplastic strategy and provide a preclinical rationale for combined inhibition of GPR171 and EGFR.

  12. Preferential enhancement of older human T cell cytokine generation, Chemotaxis, proliferation and survival by lenalidomide

    PubMed Central

    Huang, Mei-Chuan; Greig, Nigel H.; Luo, Weiming; Tweedie, David; Schwartz, Janice B.; Longo, Dan L.; Ferrucci, Luigi; Ershler, William B.; Goetzl, Edward J.

    2015-01-01

    Lenalidomide, an analog of thalidomide, modified responses of stimulated T cells from healthy young (ages 21–40 years) and old (≥age 65 years) subjects. At 0.03 μM to 1 μM, lenalidomide enhanced generation of IL-2 and IFN-γ by T cell receptor-stimulated T cells of young subjects up to respective maximum increases of 17-fold and three-fold, but at 0.3 μM and 1 μM suppressed IL-17 generation. The same concentrations of lenalidomide enhanced IL-2 and IFN-γ generation by stimulated T cells of old subjects more, with greater respective maximal increases of up to 120-fold and six-fold, without suppressing IL-17 generation. Lenalidomide enhanced proliferation and suppressed apoptosis of stimulated T cells from old subjects, by IL-2-dependent mechanisms, and restored diminished T cell chemotactic responses to CCL21 and sphingosine 1-phosphate. The reversal of T cell abnormalities of immunosenescence by low concentrations of lenalidomide suggest a potential for improvement of immunity in the elderly. PMID:21130040

  13. Enhanced proliferation of PC12 neural cells on untreated, nanotextured glass coverslips

    NASA Astrophysics Data System (ADS)

    Islam, Muhymin; Atmaramani, Rahul; Mukherjee, Siddhartha; Ghosh, Santaneel; Iqbal, Samir M.

    2016-10-01

    Traumatic injury to the central nervous system is a significant health problem. There is no effective treatment available partly because of the complexity of the system. Implementation of multifunctional micro- and nano-device based combinatorial therapeutics can provide biocompatible and tunable approaches to perform on-demand release of specific drugs. This can help the damaged cells to improve neuronal survival, regeneration of axons, and their reconnection to appropriate targets. Nano-topological features induced rapid cell growth is especially important towards the design of effective platforms to facilitate damaged neural circuit reconstruction. In this study, for the first time, feasibility of neuron-like PC12 cell growth on untreated and easy to prepare nanotextured surfaces has been carried out. The PC12 neuron-like cells were cultured on micro reactive ion etched nanotextured glass coverslips. The effect of nanotextured topology as physical cue for the growth of PC12 cells was observed exclusively, eliminating the possible influence(s) of the enhanced concentration of coated materials on the surface. The cell density was observed to increase by almost 200% on nanotextured coverslips compared to plain coverslips. The morphology study indicated that PC12 cell attachment and growth on the nanotextured substrates did not launch any apoptotic machinery of the cell. Less than 5% cells deformed and depicted condensed nuclei with apoptotic bodies on nanotextured surfaces which is typical for the normal cell handling and culture. Enhanced PC12 cell proliferation by such novel and easy to prepare substrates is not only attractive for neurite outgrowth and guidance, but may be used to increase the affinity of similar cancerous cells (ex: B35 neuroblastoma) and rapid proliferation thereafter—towards the development of combinatorial theranostics to diagnose and treat aggressive cancers like neuroblastoma.

  14. Enhanced proliferation of PC12 neural cells on untreated, nanotextured glass coverslips.

    PubMed

    Islam, Muhymin; Atmaramani, Rahul; Mukherjee, Siddhartha; Ghosh, Santaneel; Iqbal, Samir M

    2016-10-14

    Traumatic injury to the central nervous system is a significant health problem. There is no effective treatment available partly because of the complexity of the system. Implementation of multifunctional micro- and nano-device based combinatorial therapeutics can provide biocompatible and tunable approaches to perform on-demand release of specific drugs. This can help the damaged cells to improve neuronal survival, regeneration of axons, and their reconnection to appropriate targets. Nano-topological features induced rapid cell growth is especially important towards the design of effective platforms to facilitate damaged neural circuit reconstruction. In this study, for the first time, feasibility of neuron-like PC12 cell growth on untreated and easy to prepare nanotextured surfaces has been carried out. The PC12 neuron-like cells were cultured on micro reactive ion etched  nanotextured glass coverslips. The effect of nanotextured topology as physical cue for the growth of PC12 cells was observed exclusively, eliminating the possible influence(s) of the enhanced concentration of coated materials on the surface. The cell density was observed to increase by almost 200% on nanotextured coverslips compared to plain coverslips. The morphology study indicated that PC12 cell attachment and growth on the nanotextured substrates did not launch any apoptotic machinery of the cell. Less than 5% cells deformed and depicted condensed nuclei with apoptotic bodies on nanotextured surfaces which is typical for the normal cell handling and culture. Enhanced PC12 cell proliferation by such novel and easy to prepare substrates is not only attractive for neurite outgrowth and guidance, but may be used to increase the affinity of similar cancerous cells (ex: B35 neuroblastoma) and rapid proliferation thereafter-towards the development of combinatorial theranostics to diagnose and treat aggressive cancers like neuroblastoma.

  15. An optimized dosing regimen of cimaglermin (neuregulin 1β3, glial growth factor 2) enhances molecular markers of neuroplasticity and functional recovery after permanent ischemic stroke in rats

    PubMed Central

    Parry, Tom J.; Huang, Zhihong; Pavlopoulos, Elias; Finklestein, Seth P.; Ren, Jingmei; Caggiano, Anthony

    2015-01-01

    Cimaglermin (neuregulin 1β3, glial growth factor 2) is a neuregulin growth factor family member in clinical development for chronic heart failure. Previously, in a permanent middle cerebral artery occlusion (pMCAO) rat stroke model, systemic cimaglermin treatment initiated up to 7 days after ischemia onset promoted recovery without reduced lesion volume. Presented here to extend the evidence are two studies that use a rat stroke model to evaluate the effects of cimaglermin dose level and dose frequency initiated 24 hr after pMCAO. Forelimb‐ and hindlimb‐placing scores (proprioceptive behavioral tests), body‐swing symmetry, and infarct volume were compared between treatment groups (n = 12/group). Possible mechanisms underlying cimaglermin‐mediated neurologic recovery were examined through axonal growth and synapse formation histological markers. Cimaglermin was evaluated over a wider dose range (0.02, 0.1, or 1.0 mg/kg) than doses previously shown to be effective but used the same dosing regimen (2 weeks of daily intravenous administration, then 1 week without treatment). The dose‐frequency study used the dose‐ranging study's most effective dose (1.0 mg/kg) to compare daily, once per week, and twice per week dosing for 3 weeks (then 1 week without treatment). Dose‐ and frequency‐dependent functional improvements were observed with cimaglermin without reduced lesion volume. Cimaglermin treatment significantly increased growth‐associated protein 43 expression in both hemispheres (particularly somatosensory and motor cortices) and also increased synaptophysin expression. These data indicate that cimaglermin enhances recovery after stroke. Immunohistochemical changes were consistent with axonal sprouting and synapse formation but not acute neuroprotection. Cimaglermin represents a potential clinical development candidate for ischemic stroke treatment. © 2015 The Authors. Journal of Neuroscience Research Published by Wiley Periodicals, Inc

  16. Autism-Associated Chromatin Regulator Brg1/SmarcA4 Is Required for Synapse Development and Myocyte Enhancer Factor 2-Mediated Synapse Remodeling

    PubMed Central

    Zhang, Zilai; Cao, Mou; Chang, Chia-Wei; Wang, Cindy; Shi, Xuanming; Zhan, Xiaoming; Birnbaum, Shari G.; Bezprozvanny, Ilya; Huber, Kimberly M.

    2015-01-01

    Synapse development requires normal neuronal activities and the precise expression of synapse-related genes. Dysregulation of synaptic genes results in neurological diseases such as autism spectrum disorders (ASD). Mutations in genes encoding chromatin-remodeling factor Brg1/SmarcA4 and its associated proteins are the genetic causes of several developmental diseases with neurological defects and autistic symptoms. Recent large-scale genomic studies predicted Brg1/SmarcA4 as one of the key nodes of the ASD gene network. We report that Brg1 deletion in early postnatal hippocampal neurons led to reduced dendritic spine density and maturation and impaired synapse activities. In developing mice, neuronal Brg1 deletion caused severe neurological defects. Gene expression analyses indicated that Brg1 regulates a significant number of genes known to be involved in synapse function and implicated in ASD. We found that Brg1 is required for dendritic spine/synapse elimination mediated by the ASD-associated transcription factor myocyte enhancer factor 2 (MEF2) and that Brg1 regulates the activity-induced expression of a specific subset of genes that overlap significantly with the targets of MEF2. Our analyses showed that Brg1 interacts with MEF2 and that MEF2 is required for Brg1 recruitment to target genes in response to neuron activation. Thus, Brg1 plays important roles in both synapse development/maturation and MEF2-mediated synapse remodeling. Our study reveals specific functions of the epigenetic regulator Brg1 in synapse development and provides insights into its role in neurological diseases such as ASD. PMID:26459759

  17. Wip1 knockout inhibits the proliferation and enhances the migration of bone marrow mesenchymal stem cells

    SciTech Connect

    Tang, Yiting; Liu, Lan; Sheng, Ming; Xiong, Kai; Huang, Lei; Gao, Qian; Wei, Jingliang; Wu, Tianwen; Yang, Shulin; Liu, Honglin; Mu, Yulian; Li, Kui

    2015-06-10

    Mesenchymal stem cells (MSCs), a unique population of multipotent adult progenitor cells originally found in bone marrow (BM), are extremely useful for multifunctional therapeutic approaches. However, the growth arrest and premature senescence of MSCs in vitro prevent the in-depth characterization of these cells. In addition, the regulatory factors involved in MSCs migration remain largely unknown. Given that protein phosphorylation is associated with the processes of MSCs proliferation and migration, we focused on wild-type p53-inducible phosphatase-1 (Wip1), a well-studied modulator of phosphorylation, in this study. Our results showed that Wip1 knockout significantly inhibited MSCs proliferation and induced G2-phase cell-cycle arrest by reducing cyclinB1 expression. Compared with WT-MSCs, Wip1{sup −/−} MSCs displayed premature growth arrest after six passages in culture. Transwell and scratch assays revealed that Wip1{sup −/−} MSCs migrate more effectively than WT-MSCs. Moreover, the enhanced migratory response of Wip1{sup −/−} MSCs may be attributed to increases in the induction of Rac1-GTP activity, the pAKT/AKT ratio, the rearrangement of filamentous-actin (f-actin), and filopodia formation. Based on these results, we then examined the effect of treatment with a PI3K/AKT and Rac1 inhibitor, both of which impaired the migratory activity of MSCs. Therefore, we propose that the PI3K/AKT/Rac1 signaling axis mediates the Wip1 knockout-induced migration of MSCs. Our findings indicate that the principal function of Wip1 in MSCs transformation is the maintenance of proliferative capacity. Nevertheless, knocking out Wip1 increases the migratory capacity of MSCs. This dual effect of Wip1 provides the potential for purposeful routing of MSCs. - Highlights: • Wip1 knockout inhibited MSCs proliferation through reducing cyclinB1 expression. • Wip1{sup −/−} MSCs displayed premature growth arrest in vitro after six passages. • Knocking out Wip1

  18. Both estrogen receptor alpha and estrogen receptor beta agonists enhance cell proliferation in the dentate gyrus of adult female rats.

    PubMed

    Mazzucco, C A; Lieblich, S E; Bingham, B I; Williamson, M A; Viau, V; Galea, L A M

    2006-09-15

    This study investigated the involvement of estrogen receptors alpha and beta in estradiol-induced enhancement of hippocampal neurogenesis in the adult female rat. Subtype selective estrogen receptor agonists, propyl-pyrazole triol (estrogen receptor alpha agonist) and diarylpropionitrile (estrogen receptor beta agonist) were examined for each receptor's contribution, individual and cooperative, for estradiol-enhanced hippocampal cell proliferation. Estradiol increases hippocampal cell proliferation within 4 h [Ormerod BK, Lee TT, Galea LA (2003) Estradiol initially enhances but subsequently suppresses (via adrenal steroids) granule cell proliferation in the dentate gyrus of adult female rats. J Neurobiol 55:247-260]. Therefore, animals received s.c. injections of estradiol (10 microg), propyl-pyrazole triol and diarylpropionitrile alone (1.25, 2.5, 5.0 mg/0.1 ml dimethylsulfoxide) or in combination (2.5 mg propyl-pyrazole triol+2.5 mg diarylpropionitrile/0.1 ml dimethylsulfoxide) and 4 h later received an i.p. injection of the cell synthesis marker, bromodeoxyuridine (200 mg/kg). Diarylpropionitrile enhanced cell proliferation at all three administered doses (1.25 mg, P<0.008; 2.5 mg, P<0.003; 5 mg, P<0.005), whereas propyl-pyrazole triol significantly increased cell proliferation (P<0.0002) only at the dose of 2.5 mg. Our results demonstrate both estrogen receptor alpha and estrogen receptor beta are individually involved in estradiol-enhanced cell proliferation. Furthermore both estrogen receptor alpha and estrogen receptor beta mRNA was found co-localized with Ki-67 expression in the hippocampus albeit at low levels, indicating a potential direct influence of each receptor subtype on progenitor cells and their progeny. Dual receptor activation resulted in reduced levels of cell proliferation, supporting previous studies suggesting that estrogen receptor alpha and estrogen receptor beta may modulate each other's activity. Our results also suggest that a component

  19. Estradiol induces endothelial cell migration and proliferation through estrogen receptor-enhanced RhoA/ROCK pathway.

    PubMed

    Oviedo, Pilar J; Sobrino, Agua; Laguna-Fernandez, Andrés; Novella, Susana; Tarín, Juan J; García-Pérez, Miguel-Angel; Sanchís, Juan; Cano, Antonio; Hermenegildo, Carlos

    2011-03-30

    Migration and proliferation of endothelial cells are involved in re-endothelialization and angiogenesis, two important cardiovascular processes that are increased in response to estrogens. RhoA, a small GTPase which controls multiple cellular processes, is involved in the control of cell migration and proliferation. Our aim was to study the role of RhoA on estradiol-induced migration and proliferation and its dependence on estrogen receptors activity. Human umbilical vein endothelial cells were stimulated with estradiol, in the presence or absence of ICI 182780 (estrogen receptors antagonist) and Y-27632 (Rho kinase inhibitor). Estradiol increased Rho GEF-1 gene expression and RhoA (gene and protein expression and activity) in an estrogen receptor-dependent manner. Cell migration, stress fiber formation and cell proliferation were increased in response to estradiol and were also dependent on the estrogen receptors and RhoA activation. Estradiol decreased p27 levels, and significantly raised the expression of cyclins and CDK. These effects were counteracted by the use of either ICI 182780 or Y-27632. In conclusion, estradiol enhances the RhoA/ROCK pathway and increases cell cycle-related protein expression by acting through estrogen receptors. This results in an enhanced migration and proliferation of endothelial cells.

  20. Expression of peroxisome proliferator-activated receptor and CCAAT/enhancer binding protein transcription factors in cultured human sebocytes.

    PubMed

    Chen, WenChieh; Yang, Chao-Chun; Sheu, Hamm-Ming; Seltmann, Holger; Zouboulis, Christos C

    2003-09-01

    Lipid synthesis and accumulation represent a major step in sebocyte differentiation and it may be of importance for sebocytes to express two families of transcription factors, CCAAT/enhancer binding proteins (c/EBPs) and peroxisome proliferator-activated receptors (PPARs), which were found to play a crucial role in the differentiation of adipocytes. Using the immortalized human sebaceous gland cell line SZ95 we examined the expression of the molecules before and after treatment with testosterone, 5alpha-dihydrotestosterone, dexamethasone, 17beta-estradiol and genistein, at 6, 12, 24, and 48 h, respectively. Reverse transcription-PCR analysis showed expression of peroxisome proliferator-activated receptors -alpha, -delta, -gamma1, -gamma2 and CCAAT/enhancer binding proteins-alpha, -beta, -gamma-delta in native SZ95 sebocytes. In western blot studies, high levels of CCAAT/enhancer binding proteins-alpha and -beta, and peroxisome proliferator-activated receptors-gamma were expressed at 6, 24, and 12 h, respectively. Immunostaining of the cultured sebocytes showed the CCAAT/enhancer binding proteins-alpha and -beta mainly localized within nuclei, whereas peroxisome proliferator-activated receptors-gamma in the cytoplasm. Strong staining of sebocytes was immunohistochemically revealed in the basal layer of sebaceous glands in human scalp and sebaceous nevus. Genistein down-regulated the expression of CCAAT/enhancer binding proteins-alpha and -beta, and peroxisome proliferator-activated receptors-gamma on the protein level. Treatment with linoleic acid for 48 h induced further differentiation of sebocytes leading to abundant lipid synthesis.

  1. Identification of a novel human deoxynivalenol metabolite enhancing proliferation of intestinal and urinary bladder cells

    NASA Astrophysics Data System (ADS)

    Warth, Benedikt; Del Favero, Giorgia; Wiesenberger, Gerlinde; Puntscher, Hannes; Woelflingseder, Lydia; Fruhmann, Philipp; Sarkanj, Bojan; Krska, Rudolf; Schuhmacher, Rainer; Adam, Gerhard; Marko, Doris

    2016-09-01

    The mycotoxin deoxynivalenol (DON) is an abundant contaminant of cereal based food and a severe issue for global food safety. We report the discovery of DON-3-sulfate as a novel human metabolite and potential new biomarker of DON exposure. The conjugate was detectable in 70% of urine samples obtained from pregnant women in Croatia. For the measurement of urinary metabolites, a highly sensitive and selective LC-MS/MS method was developed and validated. The method was also used to investigate samples from a duplicate diet survey for studying the toxicokinetics of DON-3-sulfate. To get a preliminary insight into the biological relevance of the newly discovered DON-sulfates, in vitroexperiments were performed. In contrast to DON, sulfate conjugates lacked potency to suppress protein translation. However, surprisingly we found that DON-sulfates enhanced proliferation of human HT-29 colon carcinoma cells, primary human colon epithelial cells (HCEC-1CT) and, to some extent, also T24 bladder cancer cells. A proliferative stimulus, especially in tumorigenic cells raises concern on the potential impact of DON-sulfates on consumer health. Thus, a further characterization of their toxicological relevance should be of high priority.

  2. Enhancement of Dopaminergic Differentiation in Proliferating Midbrain Neuroblasts by Sonic Hedgehog and Ascorbic Acid

    PubMed Central

    Volpicelli, Floriana; Consales, Claudia; Caiazzo, Massimiliano; Colucci-D'Amato, Luca; Perrone-Capano, Carla; di Porzio, Umberto

    2004-01-01

    We analyzed the molecular mechanisms involved in the acquisition and maturation of dopaminergic (DA) neurons generated in vitro from rat ventral mesencephalon (MES) cells in the presence of mitogens or specific signaling molecules. The addition of basic fibroblast growth factor (bFGF) to MES cells in serum-free medium stimulates the proliferation of neuroblasts but delays DA differentiation. Recombinant Sonic hedgehog (SHH) protein increases up to three fold the number of tyrosine hydroxylase (TH)-positive cells and their differentiation, an effect abolished by anti-SHH antibodies. The expanded cultures are rich in nestin-positive neurons, glial cells are rare, all TH+ neurons are DA, and all DA and GABAergic markers analyzed are expressed. Adding ascorbic acid to bFGF/SHH-treated cultures resulted in a further five- to seven-fold enhancement of viable DA neurons. This experimental system also provides a powerful tool to generate DA neurons from single embryos. Our strategy provides an enriched source of MES DA neurons that are useful for analyzing molecular mechanisms controlling their function and for experimental regenerative approaches in DA dysfunction. PMID:15303305

  3. Identification of a novel human deoxynivalenol metabolite enhancing proliferation of intestinal and urinary bladder cells

    PubMed Central

    Warth, Benedikt; Del Favero, Giorgia; Wiesenberger, Gerlinde; Puntscher, Hannes; Woelflingseder, Lydia; Fruhmann, Philipp; Sarkanj, Bojan; Krska, Rudolf; Schuhmacher, Rainer; Adam, Gerhard; Marko, Doris

    2016-01-01

    The mycotoxin deoxynivalenol (DON) is an abundant contaminant of cereal based food and a severe issue for global food safety. We report the discovery of DON-3-sulfate as a novel human metabolite and potential new biomarker of DON exposure. The conjugate was detectable in 70% of urine samples obtained from pregnant women in Croatia. For the measurement of urinary metabolites, a highly sensitive and selective LC-MS/MS method was developed and validated. The method was also used to investigate samples from a duplicate diet survey for studying the toxicokinetics of DON-3-sulfate. To get a preliminary insight into the biological relevance of the newly discovered DON-sulfates, in vitroexperiments were performed. In contrast to DON, sulfate conjugates lacked potency to suppress protein translation. However, surprisingly we found that DON-sulfates enhanced proliferation of human HT-29 colon carcinoma cells, primary human colon epithelial cells (HCEC-1CT) and, to some extent, also T24 bladder cancer cells. A proliferative stimulus, especially in tumorigenic cells raises concern on the potential impact of DON-sulfates on consumer health. Thus, a further characterization of their toxicological relevance should be of high priority. PMID:27659167

  4. Programmed cell death-10 enhances proliferation and protects malignant T cells from apoptosis.

    PubMed

    Lauenborg, Britt; Kopp, Katharina; Krejsgaard, Thorbjørn; Eriksen, Karsten W; Geisler, Carsten; Dabelsteen, Sally; Gniadecki, Robert; Zhang, Qian; Wasik, Mariusz A; Woetmann, Anders; Odum, Niels

    2010-10-01

    The programmed cell death-10 (PDCD10; also known as cerebral cavernous malformation-3 or CCM3) gene encodes an evolutionarily conserved protein associated with cell apoptosis. Mutations in PDCD10 result in cerebral cavernous malformations, an important cause of cerebral hemorrhage. PDCD10 is associated with serine/threonine kinases and phosphatases and modulates the extracellular signal-regulated kinase pathway suggesting a role in the regulation of cellular growth. Here we provide evidence of a constitutive expression of PDCD10 in malignant T cells and cell lines from peripheral blood of cutaneous T-cell lymphoma (Sezary syndrome) patients. PDCD10 is associated with protein phosphatase-2A, a regulator of mitogenesis and apoptosis in malignant T cells. Inhibition of oncogenic signal pathways [Jak3, Notch1, and nuclear factor-κB (NF-κB)] partly inhibits the constitutive PDCD10 expression, whereas an activator of Jak3 and NF-κB, interleukin-2 (IL-2), enhances PDCD10 expression. Functional data show that PDCD10 depletion by small interfering RNA induces apoptosis and decreases proliferation of the sensitive cells. To our knowledge, these data provide the first functional link between PDCD10 and cancer.

  5. The Transcriptional Repressor ZNF503/Zeppo2 Promotes Mammary Epithelial Cell Proliferation and Enhances Cell Invasion*

    PubMed Central

    Shahi, Payam; Slorach, Euan M.; Wang, Chih-Yang; Chou, Jonathan; Lu, Angela; Ruderisch, Aline; Werb, Zena

    2015-01-01

    The NET (nocA, Nlz, elB, TLP-1) subfamily of zinc finger proteins is an important mediator during developmental processes. The evolutionary conserved zinc finger protein ZNF503/Zeppo2 (zinc finger elbow-related proline domain protein 2, Zpo2) plays critical roles during embryogenesis. We found that Zpo2 is expressed in adult tissue and examined its function. We found that ZPO2 is a nuclearly targeted transcriptional repressor that is expressed in mammary epithelial cells. Elevated Zpo2 levels increase mammary epithelial cell proliferation. Zpo2 promotes cellular invasion through down-regulation of E-cadherin and regulates the invasive phenotype in a RAC1-dependent manner. We detect elevated Zpo2 expression during breast cancer progression in a MMTV-PyMT transgenic mouse model. Tumor transplant experiments indicated that overexpression of Zpo2 in MMTV-PyMT mammary tumor cell lines enhances lung metastasis. Our findings suggest that Zpo2 plays a significant role in mammary gland homeostasis and that deregulation of Zpo2 may promote breast cancer development. PMID:25538248

  6. Overexpression of TGF-β1 enhances chondrogenic differentiation and proliferation of human synovium-derived stem cells

    SciTech Connect

    Kim, Yong Il; Ryu, Jae-Sung; Yeo, Jee Eun; Choi, Yun Jin; Kim, Yong Sang; Ko, Kinarm; Koh, Yong-Gon

    2014-08-08

    Highlights: • Continuous TGF-β1 overexpression in hSD-MSCs did not influence their phenotypes. • Retroviral-mediated transduction of TGFB1 in hSD-MSCs enhances cell proliferation. • TGF-β1 overexpression did not effect to adipo- or osteogenic potential of hSD-MSCs. • TGF-β1 overexpression in hSD-MSCs could stimulate and accelerate chondrogenesis. - Abstract: Transforming growth factor-beta (TGF-β) superfamily proteins play a critical role in proliferation, differentiation, and other functions of mesenchymal stem cells (MSCs). During chondrogenic differentiation of MSCs, TGF-β up-regulates chondrogenic gene expression by enhancing the expression of the transcription factor SRY (sex-determining region Y)-box9 (Sox9). In this study, we investigated the effect of continuous TGF-β1 overexpression in human synovium-derived MSCs (hSD-MSCs) on immunophenotype, differentiation potential, and proliferation rate. hSD-MSCs were transduced with recombinant retroviruses (rRV) encoding TGF-β1. The results revealed that continuous overexpression of TGF-β1 did not affect their phenotype as evidenced by flow cytometry and reverse transcriptase PCR (RT-PCR). In addition, continuous TGF-β1 overexpression strongly enhanced cell proliferation of hSD-MSCs compared to the control groups. Also, induction of chondrogenesis was more effective in rRV-TGFB-transduced hSD-MSCs as shown by RT-PCR for chondrogenic markers, toluidine blue staining and glycosaminoglycan (GAG)/DNA ratio. Our data suggest that overexpression of TGF-β1 positively enhances the proliferation and chondrogenic potential of hSD-MSCs.

  7. Enhanced osteoblast proliferation and corrosion resistance of commercially pure titanium through surface nanostructuring by ultrasonic shot peening and stress relieving.

    PubMed

    Jindal, Shitu; Bansal, Rajesh; Singh, Bijay P; Pandey, Rajiv; Narayanan, Shankar; Wani, Mohan R; Singh, Vakil

    2014-07-01

    This investigation was carried out to study the effect of a novel process of surface modification, surface nanostructuring by ultrasonic shot peening, on osteoblast proliferation and corrosion behavior of commercially pure titanium (c p-Ti) in simulated body fluid. A mechanically polished disc of c p-Ti was subjected to ultrasonic shot peening with stainless steel balls to create nanostructure at the surface. A nanostructure (<20 nm) with inhomogeneous distribution was revealed by atomic force and scanning electron microscopy. There was an increase of approximately 10% in cell proliferation, but there was drastic fall in corrosion resistance. Corrosion rate was increased by 327% in the shot peened condition. In order to examine the role of residual stresses associated with the shot peened surface on these aspects, a part of the shot peened specimen was annealed at 400°C for 1 hour. A marked influence of annealing treatment was observed on surface structure, cell proliferation, and corrosion resistance. Surface nanostructure was much more prominent, with increased number density and sharper grain boundaries; cell proliferation was enhanced to approximately 50% and corrosion rate was reduced by 86.2% and 41% as compared with that of the shot peened and the as received conditions, respectively. The highly significant improvement in cell proliferation, resulting from annealing of the shot peened specimen, was attributed to increased volume fraction of stabilized nanostructure, stress recovery, and crystallization of the oxide film. Increase in corrosion resistance from annealing of shot peened material was related to more effective passivation. Thus, the surface of c p-Ti, modified by this novel process, possessed a unique quality of enhancing cell proliferation as well as the corrosion resistance and could be highly effective in reducing treatment time of patients adopting dental and orthopedic implants of titanium and its alloys.

  8. Low-intensity laser phototherapy enhances the proliferation of dental pulp stem cells under nutritional deficiency.

    PubMed

    Moura-Netto, Cacio; Ferreira, Leila Soares; Maranduba, Carlos Magno; Mello-Moura, Anna Carolina Volpi; Marques, Marcia Martins

    2016-05-31

    Dental trauma in immature permanent teeth can damage pulp vascularization, which leads to necrosis and cessation of apexogenesis. Studies on tissue engineering using stem cells from human exfoliated deciduous teeth (SHEDs) have yielded promising results. Laser phototherapy (LPT) is able to influence the proliferation and differentiation of these cells, which could improve tissue engineering. SHEDs (eighth passage) were seeded into 96-well culture plates (103 cells/well) and were grown in culture medium supplemented with 15% defined fetal bovine serum (FBS) for 12 h. After determining the appropriate nutrition deficiency status (5% FBS), the cells were assigned into four groups: 1) G1 - 15% FBS (positive control); 2) G2 - 5% FBS (negative control); 3) G3 - 5% FBS+LPT 3 J/cm2; and 4) G4 - 5% FBS+LPT 5 J/cm2. For the LPT groups, two laser irradiations at 6 h intervals were performed using a continuous wave InGaAlP diode laser (660 nm, with a spot size of 0.028 cm2, 10 mW) in punctual and contact mode. Cell viability was assessed via an MTT reduction assay immediately after the second laser irradiation (0 h) and 24, 48, and 72 h later. We found that G3 and G4 presented a significantly higher cell growth rate when compared with G2 (p < 0.01). Moreover, G4 exhibited a similar cell growth rate as G1 throughout the entire experiment (p > 0.05). These findings indicate that LPT with 5 J/cm2 can enhance the growth of SHEDs during situations of nutritional deficiency. Therefore, LPT could be a valuable adjunct treatment in tissue engineering when using stem cells derived from the dental pulp of primary teeth.

  9. Propiconazole Enhances Cell Proliferation by Dysregulation of Ras Farnesylation and theMAPK pathway

    EPA Science Inventory

    Previous studies of mice exposed to the hepatotumorigenic fungicide, propiconazole, revealed an increase in hepatic cell proliferation and over-expression of hepatic genes within the cholesterol biosynthesis pathway. Mevalonate, an intermediate in this pathway, has long been a ta...

  10. Plutonium partitioning in uranium and plutonium co-recovery system for fast reactor fuel recycling with enhanced nuclear proliferation resistance

    SciTech Connect

    Nakahara, Masaumi; Koma, Yoshikazu; Nakajima, Yasuo

    2013-07-01

    For enhancement of nuclear proliferation resistance, a 'co-processing' method for U and Pu co-recovery was studied. Two concepts, no U scrubbing and no Pu reduction partitioning, were employed to formulate two types of flow sheets by using a calculation code. Their process performance was demonstrated using radioactive solutions derived from an irradiated fast reactor fuel. These experimental results indicated that U and Pu were co-recovered in the U/Pu product, and the Pu content in the U/Pu product increased approximately 2.3 times regardless of using reductant. The proposed no U scrubbing and no Pu reductant flow sheet is applicable to fast reactor fuel reprocessing and enhances its resistance to nuclear proliferation. (authors)

  11. Delta(9)-Tetrahydrocannabinol enhances MCF-7 cell proliferation via cannabinoid receptor-independent signaling.

    PubMed

    Takeda, Shuso; Yamaori, Satoshi; Motoya, Erina; Matsunaga, Tamihide; Kimura, Toshiyuki; Yamamoto, Ikuo; Watanabe, Kazuhito

    2008-03-12

    We recently reported that Delta(9)-tetrahydrocannabinol (Delta(9)-THC) has the ability to stimulate the proliferation of human breast carcinoma MCF-7 cells. However, the mechanism of action remains to be clarified. The present study focused on the relationship between receptor expression and the effects of Delta(9)-THC on cell proliferation. RT-PCR analysis demonstrated that there was no detectable expression of CB receptors in MCF-7 cells. In accordance with this, no effects of cannabinoid 1/2 (CB1/2) receptor antagonists and pertussis toxin on cell proliferation were observed. Although MCF-7 cell proliferation is suggested to be suppressed by Delta(9)-THC in the presence of CB receptors, it was revealed that Delta(9)-THC could exert upregulation of living cells in the absence of the receptors. Interestingly, Delta(9)-THC upregulated human epithelial growth factor receptor type 2 (HER2) expression, which is known to be a predictive factor of human breast cancer and is able to stimulate cancer cells as well as MCF-7 cells. Actinomycin D-treatment interfered with the upregulation of HER2 and cell proliferation by cannabinoid. Taken together, these studies suggest that, in the absence of CB receptors, Delta(9)-THC can stimulate the proliferation of MCF-7 cells by modulating, at least in part, HER2 transcription.

  12. Endogenous Hydrogen Sulfide Enhances Cell Proliferation of Human Gastric Cancer AGS Cells.

    PubMed

    Sekiguchi, Fumiko; Sekimoto, Teruki; Ogura, Ayaka; Kawabata, Atsufumi

    2016-01-01

    Hydrogen sulfide (H2S), the third gasotransmitter, is endogenously generated by certain H2S synthesizing enzymes, including cystathionine-γ-lyase (CSE) and cystathionine-β-synthase (CBS) from L-cysteine in the mammalian body. Several studies have shown that endogenous and exogenous H2S affects the proliferation of cancer cells, although the effects of H2S appear to vary with cell type, being either promotive or suppressive. In the present study, we determined whether endogenously formed H2S regulates proliferation in human gastric cancer AGS cells. CSE, but not CBS, was expressed in AGS cells. CSE inhibitors, DL-propargylglycine (PPG) and β-cyano-L-alanine (BCA), significantly suppressed the proliferation of AGS cells in a concentration-dependent manner. CSE inhibitors did not increase lactate dehydrogenase (LDH) release in the same concentration range. The inhibitory effects of PPG and BCA on cell proliferation were reversed by repetitive application of NaHS, a donor of H2S. Interestingly, nuclear condensation and fragmentation were detected in AGS cells treated with PPG or BCA. These results suggest that endogenous H2S produced by CSE may contribute to the proliferation of gastric cancer AGS cells, most probably through anti-apoptotic actions.

  13. Endogenous Cannabinoid Signaling Is Required for Voluntary Exercise-induced Enhancement of Progenitor Cell Proliferation in the Hippocampus

    PubMed Central

    Hill, Matthew N.; Titterness, Andrea K.; Morrish, Anna C.; Carrier, Erica J.; Lee, Tiffany T.-Y.; Gil-Mohapel, Joana; Gorzalka, Boris B.; Hillard, Cecilia J.; Christie, Brian R.

    2009-01-01

    Voluntary exercise and endogenous cannabinoid activity have independently been shown to regulate hippocampal plasticity. The aim of the current study was to determine whether the endocannabinoid system is regulated by voluntary exercise and if these changes contribute to exercise-induced enhancement of cell proliferation. In Experiment 1, eight days of free access to a running wheel increased the agonist binding site density of the cannabinoid CB1 receptor; CB1 receptor-mediated GTPγS binding; and the tissue content of the endocannabinoid anandamide in the hippocampus but not in the prefrontal cortex. In Experiment 2, the CB1 receptor antagonist AM251 (1 mg/kg) was administered daily to animals given free access to a running wheel for 8 days, after which cell proliferation in the hippocampus was examined through immunohistochemical analysis of the cell cycle protein Ki-67. Voluntary exercise increased proliferation of progenitor cells, as evidenced by the increase in the number of Ki-67 positive cells in the granule cell layer of the dentate gyrus in the hippocampus. However, this effect was abrogated by concurrent treatment with AM251, indicating that the increase in endocannabinoid signaling in the hippocampus is required for the exercise-induced increase in cell proliferation. These data demonstrate that the endocannabinoid system in the hippocampus is sensitive to environmental change and suggest that it is a mediator of experience-induced plasticity. PMID:19489006

  14. Extremely low-frequency electromagnetic fields enhance the proliferation and differentiation of neural progenitor cells cultured from ischemic brains.

    PubMed

    Cheng, Yannan; Dai, Yiqin; Zhu, Ximin; Xu, Haochen; Cai, Ping; Xia, Ruohong; Mao, Lizhen; Zhao, Bing-Qiao; Fan, Wenying

    2015-10-21

    In the mammalian brain, neurogenesis persists throughout the embryonic period and adulthood in the subventricular zone of the lateral ventricle and the granular zone (dentate gyrus) of the hippocampus. Newborn neural progenitor cells (NPCs) in the two regions play a critical role in structural and functional plasticity and neural regeneration after brain injury. Previous studies have reported that extremely low-frequency electromagnetic fields (ELF-EMF) could promote osteogenesis, angiogenesis, and cardiac stem cells' differentiation, which indicates that ELF-EMF might be an effective tool for regenerative therapy. The present studies were carried out to examine the effects of ELF-EMF on hippocampal NPCs cultured from embryonic and adult ischemic brains. We found that exposure to ELF-EMF (50 Hz, 0.4 mT) significantly enhanced the proliferation capability both in embryonic NPCs and in ischemic NPCs. Neuronal differentiation was also enhanced after 7 days of cumulative ELF-EMF exposure, whereas glial differentiation was not influenced markedly. The expression of phosphorylated Akt increased during the proliferation process when ischemic NPCs were exposed to ELF-EMF. However, blockage of the Akt pathway abolished the ELF-EMF-induced proliferation of ischemic NPCs. These data show that ELF-EMF promotes neurogenesis of ischemic NPCs and suggest that this effect may occur through the Akt pathway.Video abstract, Supplemental Digital Content 1, http://links.lww.com/WNR/A347.

  15. Conditional knockout of N-WASP in mouse fibroblast caused keratinocyte hyper proliferation and enhanced wound closure

    PubMed Central

    Jain, Neeraj; Kalailingam, Pazhanichamy; Tan, Kai Wei; Tan, Hui Bing; Sng, Ming Keat; Chan, Jeremy Soon Kiat; Tan, Nguan Soon; Thanabalu, Thirumaran

    2016-01-01

    Neural-Wiskott Aldrich Syndrome Protein (N-WASP) is expressed ubiquitously, regulates actin polymerization and is essential during mouse development. We have previously shown that N-WASP is critical for cell-ECM adhesion in fibroblasts. To characterize the role of N-WASP in fibroblast for skin development, we generated a conditional knockout mouse model in which fibroblast N-WASP was ablated using the Cre recombinase driven by Fibroblast Specific Protein promoter (Fsp-Cre). N-WASPFKO (N-WASPfl/fl; Fsp-cre) were born following Mendelian genetics, survived without any visible abnormalities for more than 1 year and were sexually reproductive, suggesting that expression of N-WASP in fibroblast is not critical for survival under laboratory conditions. Histological sections of N-WASPFKO mice skin (13 weeks old) showed thicker epidermis with higher percentage of cells staining for proliferation marker (PCNA), suggesting that N-WASP deficient fibroblasts promote keratinocyte proliferation. N-WASPFKO mice skin had elevated collagen content, elevated expression of FGF7 (keratinocyte growth factor) and TGFβ signaling proteins. Wound healing was faster in N-WASPFKO mice compared to control mice and N-WASP deficient fibroblasts were found to have enhanced collagen gel contraction properties. These results suggest that N-WASP deficiency in fibroblasts improves wound healing by growth factor-mediated enhancement of keratinocyte proliferation and increased wound contraction in mice. PMID:27909303

  16. Stem cell factor and interleukin-2/15 combine to enhance MAPK-mediated proliferation of human natural killer cells.

    PubMed

    Benson, Don M; Yu, Jianhua; Becknell, Brian; Wei, Min; Freud, Aharon G; Ferketich, Amy K; Trotta, Rossana; Perrotti, Danilo; Briesewitz, Roger; Caligiuri, Michael A

    2009-03-19

    Stem cell factor (SCF) promotes synergistic cellular proliferation in combination with several growth factors, and appears important for normal natural killer (NK)-cell development. CD34(+) hematopoietic precursor cells (HPCs) require interleukin-15 (IL-15) for differentiation into human NK cells, and this effect can be mimicked by IL-2. Culture of CD34(+) HPCs or some primary human NK cells in IL-2/15 and SCF results in enhanced growth compared with either cytokine alone. The molecular mechanisms responsible for this are unknown and were investigated in the present work. Activation of NK cells by IL-2/15 increases expression of c-kit whose kinase activity is required for synergy with IL-2/15 signaling. Mitogen-activated protein kinase (MAPK) signaling intermediaries that are activated both by SCF and IL-2/15 are enhanced in combination to facilitate earlier cell-cycle entry. The effect results at least in part via enhanced MAPK-mediated modulation of p27 and CDK4. Collectively the data reveal a novel mechanism by which SCF enhances cellular proliferation in combination with IL-2/15 in primary human NK cells.

  17. Overexpression of intraislet ghrelin enhances β-cell proliferation after streptozotocin-induced β-cell injury in mice.

    PubMed

    Bando, Mika; Iwakura, Hiroshi; Ariyasu, Hiroyuki; Koyama, Hiroyuki; Hosoda, Kiminori; Adachi, Souichi; Nakao, Kazuwa; Kangawa, Kenji; Akamizu, Takashi

    2013-07-01

    Previously, we reported that exogenous administration of ghrelin ameliorates glucose metabolism in a neonate streptozotocin (STZ)-induced diabetic rat model through enhancement of β-cell proliferation. However, it was not clear whether the observed β-cell proliferation was a direct or indirect effect (e.g., via orexigenic or growth hormone-stimulated pathways) of ghrelin activity. Here, we aimed to investigate whether ghrelin directly impacts β-cell proliferation after STZ-induced injury in mice. Seven-week-old male rat insulin II promoter-ghrelin internal ribosomal sequence ghrelin O-acyltransferase transgenic (RIP-GG Tg) mice, which have elevated pancreatic ghrelin levels, but only minor changes in plasma ghrelin levels when fed a medium-chain triglyceride-rich diet, were treated with STZ. Then, serum insulin, pancreatic insulin mRNA expression, and islet histology were evaluated. We found that the serum insulin levels, but not blood glucose levels, of RIP-GG Tg mice were significantly ameliorated 14 days post-STZ treatment. Pancreatic insulin mRNA expression was significantly elevated in RIP-GG Tg mice, and β-cell numbers in islets were increased. Furthermore, the number of phospho-histone H3⁺ or Ki67⁺ proliferating β-cells was significantly elevated in RIP-GG Tg mice, whereas the apoptotic indexes within the islets, as determined by TUNEL assay, were not changed. These results indicate that ghrelin can directly stimulate β-cell proliferation in vivo after β-cell injury even without its orexigenic or GH-stimulating activities, although it did not have enough impact to normalize the glucose tolerance in adult mice.

  18. Liposomes encapsulating Aloe vera leaf gel extract significantly enhance proliferation and collagen synthesis in human skin cell lines.

    PubMed

    Takahashi, Makoto; Kitamoto, Dai; Asikin, Yonathan; Takara, Kensaku; Wada, Koji

    2009-01-01

    Aloe vela leaf gel extract (AGE) are widely used as cosmetic and pharmaceutical ingredients because of its versatile skin care properties. In order to enhance the bioavailability of AGE, liposomes encapsulating AGE were prepared and examined for their interfacial and biochemical properties. The liposomes prepared from a soybean lecithin (SLP-WHITE, 1.0 wt%) by the Bangham method gave relatively a good trapping efficiency up to the AGE concentration of 0.5 wt%. The stable liposomes were then prepared from 1.0 wt% of SLP-WHITE and different concentrations of AGE by the mechanochemical method using a homogenizer and microfluidizer. The liposomes obtained from 0.25 wt% of AGE were confirmed to be small unilamellar vesicles with a diameter of less than 200 nm, and remained well dispersed for at least two weeks. The obtained liposomes encapsulating AGE were further examined for the effects on proliferation and type I collagen synthesis in normal human neonatal skin fibroblasts, NB1RGB cells. Liposomal AGE clearly showed higher proliferation rate than that of AGE alone. In addition, compared to the control, liposomal AGE significantly increased the collagen synthesis by 23%, while AGE alone showed a small effect. Liposomal AGE was also assayed for the effect on proliferation in normal human epidermal keratinocytes, NHEK(F) cells. Interestingly, liposomal AGE fractions containing 4 and 20 microg/mL of the extract considerably increased the proliferation rate by 77% and 101%, respectively. In contrast, AGE alone fractions containing 4 and 20 microg/mL of the extract increased the rate by 41% and 60%, respectively. Accordingly, the bioavailability and skin care properties of AGE will be significantly enhanced by liposome encapsulation, and the present liposomal AGE should have a great potential as an effective skin care formulation.

  19. Cadherin-12 enhances proliferation in colorectal cancer cells and increases progression by promoting EMT.

    PubMed

    Ma, Junjun; Zhao, Jingkun; Lu, Jun; Wang, Puxiongzhi; Feng, Hao; Zong, Yaping; Ou, Baochi; Zheng, Minhua; Lu, Aiguo

    2016-07-01

    Cadherin-12 (CDH12) is a subtype of N-cadherin family. In this study, we investigated the expression of CDH12 and the role of CDH12 in prognosis of colorectal cancer (CRC) patients. In addition, we observed the influence of CDH12 on proliferation and progression of CRC cell lines. By using immunohistochemical staining, we analyzed CRC samples and adjacent non-tumor tissues collected from 78 patients who underwent laparoscopic surgery in Shanghai Minimally Invasive Center, China. Statistical analyses were used to analyze relationship between CDH12 and tumor features. Kaplan-Meier method was used to analyze patients' survival. Proliferation ability of CRC cells was tested by CCK-8 assay, and transwell assays were performed to detect migration and invasion ability. Western blot assay was performed to investigate epithelial-mesenchymal transition (EMT) variants. We found that expression of CDH12 in tumor tissue was higher than in adjacent normal tissue. High expression of CDH12 was associated with tumor invasion depth and predicts poor prognosis of CRC patients. Ectopic/repressing expression of CDH12 increased/decreased the proliferation and migration ability of CRC cells. CDH12 is able to increase cancer cell migration and invasion via promoting EMT by targeting transcriptional factor Snail. These findings may conclude that CDH12 may act as a predictor in CRC patients' prognosis and an oncogene in CRC cell proliferation and migration. CDH12 may influence CRC cell progression through promoting EMT by targeting Snail. In addition, CDH12 is promoted by MCP1 through induction of MCPIP.

  20. PPARγ1 phosphorylation enhances proliferation and drug resistance in human fibrosarcoma cells

    SciTech Connect

    Pang, Xiaojuan; Shu, Yuxin; Niu, Zhiyuan; Zheng, Wei; Wu, Haochen; Lu, Yan; Shen, Pingping

    2014-03-10

    Post-translational regulation plays a critical role in the control of cell growth and proliferation. The phosphorylation of peroxisome proliferator-activated receptor γ (PPARγ) is the most important post-translational modification. The function of PPARγ phosphorylation has been studied extensively in the past. However, the relationship between phosphorylated PPARγ1 and tumors remains unclear. Here we investigated the role of PPARγ1 phosphorylation in human fibrosarcoma HT1080 cell line. Using the nonphosphorylation (Ser84 to alanine, S84A) and phosphorylation (Ser84 to aspartic acid, S84D) mutant of PPARγ1, the results suggested that phosphorylation attenuated PPARγ1 transcriptional activity. Meanwhile, we demonstrated that phosphorylated PPARγ1 promoted HT1080 cell proliferation and this effect was dependent on the regulation of cell cycle arrest. The mRNA levels of cyclin-dependent kinase inhibitor (CKI) p21{sup Waf1/Cip1} and p27{sup Kip1} descended in PPARγ1{sup S84D} stable HT1080 cell, whereas the expression of p18{sup INK4C} was not changed. Moreover, compared to the PPARγ1{sup S84A}, PPARγ1{sup S84D} up-regulated the expression levels of cyclin D1 and cyclin A. Finally, PPARγ1 phosphorylation reduced sensitivity to agonist rosiglitazone and increased resistance to anticancer drug 5-fluorouracil (5-FU) in HT1080 cell. Our findings establish PPARγ1 phosphorylation as a critical event in human fibrosarcoma growth. These findings raise the possibility that chemical compounds that prevent the phosphorylation of PPARγ1 could act as anticancer drugs. - Highlights: • Phosphorylation attenuates PPARγ1 transcriptional activity. • Phosphorylated PPARγ1 promotes HT1080 cells proliferation. • PPARγ1 phosphorylation regulates cell cycle by mediating expression of cell cycle regulators. • PPARγ1 phosphorylation reduces sensitivity to agonist and anticancer drug. • Our findings establish PPARγ1 phosphorylation as a critical event in HT1080

  1. Enhancement by Wy-14,643, a hepatic peroxisome proliferator, of diethylnitrosamine-initiated hepatic tumorigenesis in the rat.

    PubMed Central

    Reddy, J. K.; Rao, M. S.

    1978-01-01

    Diethylnitrosamine (DEN), at a concentration of 100 parts/10(6) in drinking water for 14 days, caused the development, by 48 weeks, of very few liver tumours in 5 of 18 (27%) male F=344 rats fed control diet. When the DEN treatment was followed one week later by continuous feeding of the hypolipidemic hepatic peroxisome proliferator, Wy-14,643, at 0.1% dietary level, all of 28 rats (100%) developed, between 38 and 48 weeks, a significantly higher number of liver tumours. Furthermore, laparotomy at 22 weeks revealed that several rats fed Wy-14,643 after DEN initiation had developed visible liver nodules, suggesting that Wy-14,643 also accelerates the appearance of these tumours. Administration of another peroxisome proliferator, clofibrate, at 0.5% level in the diet after DEN initiation, also caused a substantial enhancement of liver tumorigenesis. The enhancement of liver-tumour development by clofibrate, however, was less than that by Wy-14,643. The marked enhancing effect of Wy-14,643 may be due to its profound hepatomegalic and peroxisome proliferative properties. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 PMID:728341

  2. Methylglyoxal, a reactive glucose metabolite, enhances autophagy flux and suppresses proliferation of human retinal pigment epithelial ARPE-19 cells.

    PubMed

    Chang, Yo-Chen; Hsieh, Ming-Chu; Wu, Horng-Jiun; Wu, Wen-Chuan; Kao, Ying-Hsien

    2015-10-01

    Methylglyoxal (MGO), a glycolytic metabolite, induces oxidative injury and apoptotic cell death that play a pathogenetic role in age-related macular degeneration (AMD). This study examined the impact of MGO on cell proliferation and autophagy flux in retinal pigment epithelium (RPE) ARPE-19 cells and elucidated the underlying mechanism. Short-term MGO exposure suppressed cell proliferation without induction of apoptotic cell death, increased production of reactive oxygen species, and potentiated H2O2-exhibited cytotoxicity in ARPE-19 cells. Conversely, pretreatment with N-acetylcysteine, a ROS scavenger, and aminoguanidine, an MGO blocker, prevented MGO-induced growth retardation. MGO significantly enhanced autophagy flux and increased intracellular accumulation of autophagosomes, which was functionally confirmed by addition of autophagy enhancer or inhibitors. Signaling kinetic observation indicated that MGO remarkably triggered phosphorylation of Akt, ERK1/2, p38 MAPK, and JNK1/2. Blockade of kinase activity demonstrated that the hyperphosphorylation of Akt, ERK1/2, JNK, and p38 MAPK were all involved in the MGO-enhanced autophagy and growth-arresting effect in ARPE-19 cells. Moreover, pretreatment with autophagic flux inhibitors including 3-methyladenine, bafilomycin A, and chloroquine effectively ameliorated MGO- but not H2O2-mediated ARPE-19 cytotoxicity. In conclusion, modulation of autophagy flux activity by using autophagic or kinase inhibitors may be an applicable modality to treat AMD.

  3. B-Myb enhances proliferation and suppresses differentiation of keratinocytes in three-dimensional cell culture.

    PubMed

    Maruyama, Hiroshi; Ishitsuka, Yosuke; Fujisawa, Yasuhiro; Furuta, Junichi; Sekido, Mitsuru; Kawachi, Yasuhiro

    2014-05-01

    B-Myb (Mybl2) is a member of the Myb gene family of transcription factors involved in the control of cell growth, differentiation, and apoptosis. The effects of B-Myb on keratinocyte proliferation and differentiation have not yet been clarified. The present study was performed to examine the role of B-Myb in proliferation and differentiation of the spontaneously immortalized human skin keratinocyte cell line HaCaT and normal human keratinocytes with formation of a stratified epidermoid structure in air-liquid interface three-dimensional culture. B-Myb was expressed specifically in undifferentiated normal keratinocytes and downregulated during differentiation. The constitutive overexpression of B-Myb in HaCaT cells during air exposure-induced differentiation resulted in an undifferentiated phenotype, i.e., thickening of the stratified layers, suppression of differentiation marker expression, and retention of proliferative activity with activation of cell cycle regulatory proteins in the S and G2/M phases. In contrast, suppression of B-Myb caused their downregulation and constrained proliferation with retention of differentiation capacity. These findings suggested that B-Myb plays an important role in maintenance of the undifferentiated phenotype of keratinocytes in the basal epidermal layer.

  4. Chemosensitizing effects of carbon-based nanomaterials in cancer cells: enhanced apoptosis and inhibition of proliferation as underlying mechanisms

    NASA Astrophysics Data System (ADS)

    Erdmann, Kati; Ringel, Jessica; Hampel, Silke; Rieger, Christiane; Huebner, Doreen; Wirth, Manfred P.; Fuessel, Susanne

    2014-10-01

    Recent studies have shown that carbon nanomaterials such as carbon nanofibres (CNFs) and multi-walled carbon nanotubes (CNTs) can exert antitumor activities themselves and sensitize cancer cells to conventional chemotherapeutics such as carboplatin and cisplatin. In the present study, the chemosensitizing effect of CNFs and CNTs on cancer cells of urological origin was investigated regarding the underlying mechanisms. Prostate cancer (DU-145, PC-3) and bladder cancer (EJ28) cells were treated with carbon nanomaterials (CNFs, CNTs) and chemotherapeutics (carboplatin, cisplatin) alone as well as in combination for 24 h. Forty-eight (EJ28) or 72 h (DU-145, PC-3) after the end of treatment the effects on cellular proliferation, clonogenic survival, cell death rate and cell cycle distribution were evaluated. Depending on the cell line, simultaneous administration of chemotherapeutics and carbon nanomaterials produced an additional inhibition of cellular proliferation and clonogenic survival of up to 77% and 98%, respectively, compared to the inhibitory effects of the chemotherapeutics alone. These strongly enhanced antiproliferative effects were accompanied by an elevated cell death rate, which was predominantly mediated via apoptosis and not by necrosis. The antitumor effects of combinations with CNTs were less pronounced than those with CNFs. The enhanced effects of the combinatory treatments on cellular function were mostly of additive to partly synergistic nature. Furthermore, cell cycle analysis demonstrated an arrest at the G2/M phase mediated by a monotreatment with chemotherapeutics. Following combinatory treatments, mostly less than or nearly additive increases of cell fractions in the G2/M phase could be observed. In conclusion, the pronounced chemosensitizing effects of CNFs and CNTs were mediated by an enhanced apoptosis and inhibition of proliferation. The combination of carbon-based nanomaterials and conventional chemotherapeutics represents a novel

  5. Suppression of hepatocellular carcinoma cell proliferation by short hairpin RNA of frizzled 2 with Sonazoid-enhanced irradiation.

    PubMed

    Tomizawa, Minoru; Shinozaki, Fuminobu; Motoyoshi, Yasufumi; Sugiyama, Takao; Yamamoto, Shigenori; Ishige, Naoki

    2016-01-01

    Short-hairpin RNA of frizzled-2 (shRNA-Fz2) is known to suppress the proliferation of hepatocellular carcinoma (HCC) cells; however, its effect on HCC cell motility is unknown. In this study, suppression of HCC cell motility by shRNA-Fz2 was analyzed, and introduction of shRNA-Fz2 into HCC cells was facilitated with ultrasound (US) irradiation generated from a diagnostic US device, which was enhanced by the contrast-enhanced US reagent Sonazoid. The HCC cell lines HLF and PLC/PRF/5 that were transfected with shRNA-Fz2 were plated to form monolayers, following which the cell monolayers were scratched with a sterile razor. After 48 h, the cells were stained with hematoxylin and eosin, and the distance between the growing edge of the cell layer and the scratch lines was measured. Total RNA from the cells was isolated and subjected to real-time quantitative PCR to quantify matrix metalloproteinase 9 expression at 48 h after transfection of shRNA-Fz2. Starch-iodide method was applied to analyze the generation of H2O2 following US irradiation with the addition of Sonazoid in the liquid, and cell proliferation was analyzed 72 h later. The distances between the growing edge of the cell layer and the scratch lines and MMP9 expression levels were significantly decreased with transfection of shRNA-Fz2 (P<0.05). In the starch-iodide method, absorbance significantly decreased with the addition of Sonazoid (P<0.05), which suggested that US irradiation with Sonazoid generated H2O2 and enhanced sonoporation. ShRNA-Fz2 suppressed cell proliferation of both cell lines at a mechanical index of 0.4. Motility of HLF cells and PLC/PRF/5 cells was suppressed by shRNA-FZ2. Sonazoid enhanced sonoporation of the cells with the diagnostic US device and the suppression of proliferation of both HCC cell lines by shRNA-Fz2.

  6. The MMP-1/PAR-1 Axis Enhances Proliferation and Neuronal Differentiation of Adult Hippocampal Neural Progenitor Cells

    PubMed Central

    Valente, Maria Maddalena; Allen, Megan; Bortolotto, Valeria; Lim, Seung T.; Conant, Katherine; Grilli, Mariagrazia

    2015-01-01

    Matrix metalloproteinases (MMPs) are zinc-dependent endopeptidases that play a role in varied forms of developmental and postnatal neuroplasticity. MMP substrates include protease-activated receptor-1 (PAR-1), a G-protein coupled receptor expressed in hippocampus. We examined proliferation and differentiation of adult neural progenitor cells (aNPCs) from hippocampi of mice that overexpress the potent PAR-1 agonist MMP-1. We found that, as compared to aNPCs from littermate controls, MMP-1 tg aNPCs display enhanced proliferation. Under differentiating conditions, these cells give rise to a higher percentage of MAP-2+ neurons and a reduced number of oligodendrocyte precursors, and no change in the number of astrocytes. The fact that these results are MMP and PAR-1 dependent is supported by studies with distinct antagonists. Moreover, JSH-23, an inhibitor of NF-κB p65 nuclear translocation, counteracted both the proliferation and differentiation changes seen in MMP-1 tg-derived NPCs. In complementary studies, we found that the percentage of Sox2+ undifferentiated progenitor cells is increased in hippocampi of MMP-1 tg animals, compared to wt mice. Together, these results add to a growing body of data suggesting that MMPs are effectors of hippocampal neuroplasticity in the adult CNS and that the MMP-1/PAR-1 axis may play a role in neurogenesis following physiological and/or pathological stimuli. PMID:26783471

  7. Enhanced cellular uptake and anti-proliferating effect of chitosan hydrochlorides modified genistein loaded NLC on human lens epithelial cells.

    PubMed

    Zhang, Wenji; Liu, Jinlu; Zhang, Qi; Li, Xuedong; Yu, Shihui; Yang, Xinggang; Kong, Jun; Pan, Weisan

    2014-08-25

    This study was attempted to increase the cellular uptake of developed genistein loaded nanostructured lipid carriers (NLC) into human lens epithelial (HLE) cells by chitosan hydrochlorides coatings when applied in post lens capsule (PCO) treatment, and to provide further understanding of the uptake and anti-proliferation mechanisms inside. NLCs were produced using melt-emulsification method and were subsequently coated with chitosan hydrochlorides by adsorption. The uptake of various particle sizes were evaluated and visualized by confocal laser scanning microscopy (CLSM), showing a size-dependent manner. The uptake of NLC was proved to be endocytosed in an energy dependent and clathrin-mediated endocytosis to HLE cells by the decrease in uptake at lower temperature, when pre-saturated by blank NLC and in the presence of NaN3 and sucrose. CH coating improved the uptake percentage of NLC irrespective of the particle size, without influencing the uptake mechanism. Cell apoptosis was tested using PI and Annexin V-FITC/PI staining, followed by flow cytometer analysis. Higher anti-proliferation effect was observed for CH-NLC in inhibiting the growth of HLE cells by causing more apoptosis. Results above indicate that GEN-NLC surface modified by chitosan hydrochlorides could enhance the trans-cellular performance and anti-proliferating effect as PCO therapy.

  8. [Fibroblast growth factor-2].

    PubMed

    Faitová, J

    2004-01-01

    Fibroblast growth factor-2 is a member of a large family of proteins that bind heparin and heparan sulfate and modulate the function of a wide range of cell types. FGF-2 occurs in several isoforms resulting from alternative initiations of traslation: an 18 kDa cytoplasmic isoform and four larger molecular weight nuclear isoforms (22, 22.5, 24 and 34 kDa). It acts mainly through a paracrine/autocrine mechanism involving high affinity transmembrane receptors and heparan sulfate proteoglycan low affinity receptors. It is expressed mostly in tissues of mesoderm and neuroectoderm origin, and plays an important role in mesoderm induction, stimulates the growth and development of the new blood vessels (angiogenesis), normal wound healing and tissue development. FGF-2 positively regulates hematopoiesis by acting on various cellular targets: stromal cells, early and committed hematopoietic progenitors and possibly some mature blood cells. FGF-2 is a potent hematopoietic growth factor that is likely to play an important role in physiological and pathological hematopoiesis.

  9. Synthesis of trace element Si and Sr codoping hydroxyapatite with non-cytotoxicity and enhanced cell proliferation and differentiation.

    PubMed

    Gao, Jianyong; Wang, Ming; Shi, Chao; Wang, Liping; Wang, Dalin; Zhu, Yingchun

    2016-11-01

    The main inorganic minerals in natural bones are non-stoichiometric hydroxyapatite (HA, Ca10[PO4]6[OH]2) doped with various trace elements, which may possess important biochemical effects. To investigate the functions of Sr and Si elements in human hard tissues, non-doped HA, trace Si doped HA, Si and Sr codoped HA with the concentration of natural bones are synthesized by hydrothermal method in this study. The samples are characterized by powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscope (SEM). The biological activities are evaluated via cytotoxicity study, adhesion and proliferation of osteoblast measurement, and alkaline phosphatase (ALP) assay. All the synthesized materials are HA phase, which have hierarchical structures with oriented HA nanorods assembled into the platy particles. These materials are non-cytotoxic against L929 cells line even at 400 μg/ml powder suspension. The results clearly indicate that the proliferation of L929 cells increases with trace elements doping from trace Si-HA to Si + Sr-HA. The adhesion and proliferation of osteoblast measurement illustrates that proliferation of osteoblasts advances about 1.3 times for Si-HA and about 1.8 times for Si + Sr-HA compared with undoped HA. In general, Si-HA with trace Si element shows enhanced cell differentiation, and Si + Sr-HA dual-doped with Si and Sr elements presents increased biological activity compared with Si-HA.

  10. Bio-active molecules modified surfaces enhanced mesenchymal stem cell adhesion and proliferation.

    PubMed

    Mobasseri, Rezvan; Tian, Lingling; Soleimani, Masoud; Ramakrishna, Seeram; Naderi-Manesh, Hossein

    2017-01-29

    Surface modification of the substrate as a component of in vitro cell culture and tissue engineering, using bio-active molecules including extracellular matrix (ECM) proteins or peptides derived ECM proteins can modulate the surface properties and thereby induce the desired signaling pathways in cells. The aim of this study was to evaluate the behavior of human bone marrow mesenchymal stem cells (hBM-MSCs) on glass substrates modified with fibronectin (Fn), collagen (Coll), RGD peptides (RGD) and designed peptide (R-pept) as bio-active molecules. The glass coverslips were coated with fibronectin, collagen, RGD peptide and R-peptide. Bone marrow mesenchymal stem cells were cultured on different substrates and the adhesion behavior in early incubation times was investigated using scanning electron microscopy (SEM) and confocal microscopy. The MTT assay was performed to evaluate the effect of different bio-active molecules on MSCs proliferation rate during 24 and 72 h. Formation of filopodia and focal adhesion (FA) complexes, two steps of cell adhesion process, were observed in MSCs cultured on bio-active molecules modified coverslips, specifically in Fn coated and R-pept coated groups. SEM image showed well adhesion pattern for MSCs cultured on Fn and R-pept after 2 h incubation, while the shape of cells cultured on Coll and RGD substrates indicated that they might experience stress condition in early hours of culture. Investigation of adhesion behavior, as well as proliferation pattern, suggests R-peptide as a promising bio-active molecule to be used for surface modification of substrate in supporting and inducing cell adhesion and proliferation.

  11. Abeta 1-40 Enhances the Proliferation of Human Diploid Fibroblasts

    PubMed Central

    Theda, Lindsey; Drews, Michelle K.; Zitnik, Galynn; Oshima, Junko; Martin, George M.

    2015-01-01

    There is a vast literature on the role of beta amyloid (Aβ) peptides in the pathogenesis of Alzheimer’s disease. There is a paucity of research, however, on potential physiological functions of these evolutionarily conserved products of the β amyloid precursor protein (APP). Based on previous studies in neuroblastoma cells (Zitnik, et al., 2007), we hypothesized that Aβ may contribute to the proliferation of somatic cells. We present evidence supporting this hypothesis for the case of cultured hTERT immortalized human skin fibroblasts. Optimal concentrations ranged from 100 pM – 10 nM, depending upon the nature of the assay. PMID:26827638

  12. OPTIMIZATION OF HETEROGENEOUS UTILIZATION OF THORIUM IN PWRS TO ENHANCE PROLIFERATION RESISTANCE AND REDUCE WASTE.

    SciTech Connect

    TODOSOW,M.; KAZIMI,M.

    2004-08-01

    Issues affecting the implementation, public perception and acceptance of nuclear power include: proliferation, radioactive waste, safety, and economics. The thorium cycle directly addresses the proliferation and waste issues, but optimization studies of core design and fuel management are needed to ensure that it fits within acceptable safety and economic margins. Typical pressurized water reactors, although loaded with uranium fuel, produce 225 to 275 kg of plutonium per gigawatt-year of operation. Although the spent fuel is highly radioactive, it nevertheless offers a potential proliferation pathway because the plutonium is relatively easy to separate, amounts to many critical masses, and does not present any significant intrinsic barrier to weapon assembly. Uranium 233, on the other hand, produced by the irradiation of thorium, although it too can be used in weapons, may be ''denatured'' by the addition of natural, depleted or low enriched uranium. Furthermore, it appears that the chemical behavior of thoria or thoria-urania fuel makes it a more stable medium for the geological disposal of the spent fuel. It is therefore particularly well suited for a once-through fuel cycle. The use of thorium as a fertile material in nuclear fuel has been of interest since the dawn of nuclear power technology due to its abundance and to potential neutronic advantages. Early projects include homogeneous mixtures of thorium and uranium oxides in the BORAX-IV, Indian Point I, and Elk River reactors, as well as heterogeneous mixtures in the Shippingport seed-blanket reactor. However these projects were developed under considerably different circumstances than those which prevail at present. The earlier applications preceded the current proscription, for non-proliferation purposes, of the use of uranium enriched to more than 20 w/o in {sup 235}U, and has in practice generally prohibited the use of uranium highly enriched in {sup 235}U. They were designed when the expected burnup of

  13. Conditionally immortalized human pancreatic stellate cell lines demonstrate enhanced proliferation and migration in response to IGF-I

    SciTech Connect

    Rosendahl, Ann H.; Gundewar, Chinmay; Said Hilmersson, Katarzyna; Ni, Lan; Saleem, Moin A.; Andersson, Roland

    2015-01-15

    Pancreatic stellate cells (PSCs) play a key role in the dense desmoplastic stroma associated with pancreatic ductal adenocarcinoma. Studies on human PSCs have been minimal due to difficulty in maintaining primary PSC in culture. We have generated the first conditionally immortalized human non-tumor (NPSC) and tumor-derived (TPSC) pancreatic stellate cells via transformation with the temperature-sensitive SV40 large T antigen and human telomerase (hTERT). These cells proliferate at 33°C. After transfer to 37°C, the SV40LT is switched off and the cells regain their primary PSC phenotype and growth characteristics. NPSC contained cytoplasmic vitamin A-storing lipid droplets, while both NPSC and TPSC expressed the characteristic markers αSMA, vimentin, desmin and GFAP. Proteome array analysis revealed that of the 55 evaluated proteins, 27 (49%) were upregulated ≥3-fold in TPSC compared to NPSC, including uPA, pentraxin-3, endoglin and endothelin-1. Two insulin-like growth factor binding proteins (IGFBPs) were inversely expressed. Although discordant IGFBP-2 and IGFBP-3 levels, IGF-I was found to stimulate proliferation of both NPSC and TPSC. Both basal and IGF-I stimulated motility was significantly enhanced in TPSC compared to NPSC. In conclusion, these cells provide a unique resource that will facilitate further study of the active stroma compartment associated with pancreatic cancer. - Highlights: • Generation of human conditionally immortalized human pancreatic stellate cell lines. • Temperature-sensitive SV40LT allows switch to primary PSC phenotype characteristics. • Proteome profiling revealed distinct expression patterns between TPSC and NPSC. • Enhanced IGF-I-stimulated proliferation and motility by TPSC compared to NPSC.

  14. Human neural stem cells promote proliferation of endogenous neural stem cells and enhance angiogenesis in ischemic rat brain.

    PubMed

    Ryu, Sun; Lee, Seung-Hoon; Kim, Seung U; Yoon, Byung-Woo

    2016-02-01

    Transplantation of human neural stem cells into the dentate gyrus or ventricle of rodents has been reportedly to enhance neurogenesis. In this study, we examined endogenous stem cell proliferation and angiogenesis in the ischemic rat brain after the transplantation of human neural stem cells. Focal cerebral ischemia in the rat brain was induced by middle cerebral artery occlusion. Human neural stem cells were transplanted into the subventricular zone. The behavioral performance of human neural stem cells-treated ischemic rats was significantly improved and cerebral infarct volumes were reduced compared to those in untreated animals. Numerous transplanted human neural stem cells were alive and preferentially localized to the ipsilateral ischemic hemisphere. Furthermore, 5-bromo-2'-deoxyuridine-labeled endogenous neural stem cells were observed in the subventricular zone and hippocampus, where they differentiated into cells immunoreactive for the neural markers doublecortin, neuronal nuclear antigen NeuN, and astrocyte marker glial fibrillary acidic protein in human neural stem cells-treated rats, but not in the untreated ischemic animals. The number of 5-bromo-2'-deoxyuridine-positive ⁄ anti-von Willebrand factor-positive proliferating endothelial cells was higher in the ischemic boundary zone of human neural stem cells-treated rats than in controls. Finally, transplantation of human neural stem cells in the brains of rats with focal cerebral ischemia promoted the proliferation of endogenous neural stem cells and their differentiation into mature neural-like cells, and enhanced angiogenesis. This study provides valuable insights into the effect of human neural stem cell transplantation on focal cerebral ischemia, which can be applied to the development of an effective therapy for stroke.

  15. Fatty acid synthase as a factor required for exercise-induced cognitive enhancement and dentate gyrus cellular proliferation.

    PubMed

    Chorna, Nataliya E; Santos-Soto, Iván J; Carballeira, Nestor M; Morales, Joan L; de la Nuez, Janneliz; Cátala-Valentin, Alma; Chornyy, Anatoliy P; Vázquez-Montes, Adrinel; De Ortiz, Sandra Peña

    2013-01-01

    Voluntary running is a robust inducer of adult hippocampal neurogenesis. Given that fatty acid synthase (FASN), the key enzyme for de novo fatty acid biosynthesis, is critically involved in proliferation of embryonic and adult neural stem cells, we hypothesized that FASN could mediate both exercise-induced cell proliferation in the subgranular zone (SGZ) of the dentate gyrus (DG) and enhancement of spatial learning and memory. In 20 week-old male mice, voluntary running-induced hippocampal-specific upregulation of FASN was accompanied also by hippocampal-specific accumulation of palmitate and stearate saturated fatty acids. In experiments addressing the functional role of FASN in our experimental model, chronic intracerebroventricular (i.c.v.) microinfusions of C75, an irreversible FASN inhibitor, and significantly impaired exercise-mediated improvements in spatial learning and memory in the Barnes maze. Unlike the vehicle-injected mice, the C75 group adopted a non-spatial serial escape strategy and displayed delayed escape latencies during acquisition and memory tests. Furthermore, pharmacologic blockade of FASN function with C75 resulted in a significant reduction, compared to vehicle treated controls, of the number of proliferative cells in the DG of running mice as measured by immunoreactive to Ki-67 in the SGZ. Taken together, our data suggest that FASN plays an important role in exercise-mediated cognitive enhancement, which might be associated to its role in modulating exercise-induced stimulation of neurogenesis.

  16. Fatty Acid Synthase as a Factor Required for Exercise-Induced Cognitive Enhancement and Dentate Gyrus Cellular Proliferation

    PubMed Central

    Chorna, Nataliya E.; Santos-Soto, Iván J.; Carballeira, Nestor M.; Morales, Joan L.; de la Nuez, Janneliz; Cátala-Valentin, Alma; Chornyy, Anatoliy P.; Vázquez-Montes, Adrinel; De Ortiz, Sandra Peña

    2013-01-01

    Voluntary running is a robust inducer of adult hippocampal neurogenesis. Given that fatty acid synthase (FASN), the key enzyme for de novo fatty acid biosynthesis, is critically involved in proliferation of embryonic and adult neural stem cells, we hypothesized that FASN could mediate both exercise-induced cell proliferation in the subgranular zone (SGZ) of the dentate gyrus (DG) and enhancement of spatial learning and memory. In 20 week-old male mice, voluntary running-induced hippocampal-specific upregulation of FASN was accompanied also by hippocampal-specific accumulation of palmitate and stearate saturated fatty acids. In experiments addressing the functional role of FASN in our experimental model, chronic intracerebroventricular (i.c.v.) microinfusions of C75, an irreversible FASN inhibitor, and significantly impaired exercise-mediated improvements in spatial learning and memory in the Barnes maze. Unlike the vehicle-injected mice, the C75 group adopted a non-spatial serial escape strategy and displayed delayed escape latencies during acquisition and memory tests. Furthermore, pharmacologic blockade of FASN function with C75 resulted in a significant reduction, compared to vehicle treated controls, of the number of proliferative cells in the DG of running mice as measured by immunoreactive to Ki-67 in the SGZ. Taken together, our data suggest that FASN plays an important role in exercise-mediated cognitive enhancement, which might be associated to its role in modulating exercise-induced stimulation of neurogenesis. PMID:24223732

  17. Enhanced engraftment, proliferation, and therapeutic potential in heart using optimized human iPSC-derived cardiomyocytes

    PubMed Central

    Funakoshi, Shunsuke; Miki, Kenji; Takaki, Tadashi; Okubo, Chikako; Hatani, Takeshi; Chonabayashi, Kazuhisa; Nishikawa, Misato; Takei, Ikue; Oishi, Akiko; Narita, Megumi; Hoshijima, Masahiko; Kimura, Takeshi; Yamanaka, Shinya; Yoshida, Yoshinori

    2016-01-01

    Human pluripotent stem cell-derived cardiomyocytes (CMs) are a promising tool for cardiac cell therapy. Although transplantation of induced pluripotent stem cell (iPSC)-derived CMs have been reported in several animal models, the treatment effect was limited, probably due to poor optimization of the injected cells. To optimize graft cells for cardiac reconstruction, we compared the engraftment efficiency of intramyocardially-injected undifferentiated-iPSCs, day4 mesodermal cells, and day8, day20, and day30 purified iPSC-CMs after initial differentiation by tracing the engraftment ratio (ER) using in vivo bioluminescence imaging. This analysis revealed the ER of day20 CMs was significantly higher compared to other cells. Transplantation of day20 CMs into the infarcted hearts of immunodeficient mice showed good engraftment, and echocardiography showed significant functional improvement by cell therapy. Moreover, the imaging signal and ratio of Ki67-positive CMs at 3 months post injection indicated engrafted CMs proliferated in the host heart. Although this graft growth reached a plateau at 3 months, histological analysis confirmed progressive maturation from 3 to 6 months. These results suggested that day20 CMs had very high engraftment, proliferation, and therapeutic potential in host mouse hearts. They also demonstrate this model can be used to track the fate of transplanted cells over a long time. PMID:26743035

  18. Enhancing proliferation and ECM expression of human ACL fibroblasts by sonic vibration.

    PubMed

    Jiang, Yuan-Yuan; Park, Jung-Keug; Yoon, Hee-Hoon; Choi, Hynjin; Kim, Chan-Wha; Seo, Young-Kwon

    2015-01-01

    Effects of mechanical vibration on cell activity and behavior remain controversial: There has been evidence on both positive and negative effects. Furthermore, research on the anterior cruciate ligament (ACL) has as yet been limited and the frequency-related effects remain unknown, even though ACL injury is common and an injured ACL hardly spontaneously recovers. The object of this work was to address the influence of mechanical vibration on ACL fibroblasts, to determine the effects of frequencies, and to further study this effect at the cellular level. We found that sonic vibration affected ACL fibroblasts' proliferation and metabolism in a frequency-dependent manner, and 20 Hz gave rise to the most ACL cell activity and comprehensively increased extracellular matrix (ECM) contents, including collagen type I, collagen type III, fibronectin, elastin, tenascin, glycosaminoglycan (GAG), and the cytoskeleton protein vimentin. Thus, our results indicate that sonic vibration possesses frequency-dependent effects on proliferation and productivity of ACL fibroblast with an optimal frequency of 20 Hz under the present stimulation conditions, providing further information for future research in how vibrational stimulation manipulates ACL cellular behavior.

  19. Loss of hypoxia-inducible factor 2 alpha in the lung alveolar epithelium of mice leads to enhanced eosinophilic inflammation in cobalt-induced lung injury.

    PubMed

    Proper, Steven P; Saini, Yogesh; Greenwood, Krista K; Bramble, Lori A; Downing, Nathaniel J; Harkema, Jack R; Lapres, John J

    2014-02-01

    Hard metal lung disease (HMLD) is an occupational lung disease specific to inhalation of cobalt-containing particles whose mechanism is largely unknown. Cobalt is a known hypoxia mimic and stabilizer of the alpha subunits of hypoxia-inducible factors (HIFs). Previous work revealed that though HIF1α contrib utes to cobalt toxicity in vitro, loss of HIF1α in the alveolar epithelial cells does not provide in vivo protection from cobalt-induced lung inflammation. HIF1α and HIF2α show unique tissue expression profiles, and HIF2α is known to be the predominant HIF mRNA isoform in the adult lung. Thus, if HIF2α activation by cobalt contributes to pathophysiology of HMLD, we hypothesized that loss of HIF2α in lung epithelium would provide protection from cobalt-induced inflammation. Mice with HIF2α-deficiency in Club and alveolar type II epithelial cells (ATIIs) (HIF2α(Δ/Δ)) were exposed to cobalt (60 µg/day) or saline using a subacute occupational exposure model. Bronchoalveolar lavage cellularity, cytokines, qRT-PCR, and histopathology were analyzed. Results show that loss of HIF2α leads to enhanced eosinophilic inflammation and increased goblet cell metaplasia. Additionally, control mice demonstrated a mild recovery from cobalt-induced lung injury compared with HIF2α(Δ/Δ) mice, suggesting a role for epithelial HIF2α in repair mechanisms. The expression of important cytokines, such as interleukin (IL)-5 and IL-10, displayed significant differences following cobalt exposure when HIF2α(Δ/Δ) and control mice were compared. In summary, our data suggest that although loss of HIF2α does not afford protection from cobalt-induced lung inflammation, epithelial HIF2α signaling does play an important role in modulating the inflammatory and repair response in the lung.

  20. Overexpression of HE4 (human epididymis protein 4) enhances proliferation, invasion and metastasis of ovarian cancer

    PubMed Central

    Wang, Huimin; Tan, Mingzi; Schwab, Carlton L.; Deng, Lu; Gao, Jian; Hao, Yingying; Li, Xiao; Gao, Song; Liu, Juanjuan; Lin, Bei

    2016-01-01

    Overexpression of Human epididymis protein 4 (HE4) related with a role in ovarian cancer tumorigenesis while little is known about the molecular mechanism alteration by HE4 up regulation. Here we reported that overexpressed HE4 promoted ovarian cancer cells proliferation, invasion and metastasis. Furthermore, human whole genome gene expression profile microarrays revealed that 231 differentially expressed genes (DEGs) were altered in response to HE4, in which MAPK signaling, ECM receptor, cell cycle, steroid biosynthesis pathways were involved. The findings suggested that overexpressed HE4 played an important role in ovarian cancer progression and metastasis and that HE4 has the potential to serve as a novel therapeutic target for ovarian cancer. PMID:26575020

  1. Wound repair and proliferation of bronchial epithelial cells enhanced by bombesin receptor subtype 3 activation.

    PubMed

    Tan, Yu-Rong; Qi, Ming-Ming; Qin, Xiao-Qun; Xiang, Yang; Li, Xiang; Wang, Yue; Qu, Fei; Liu, Hui-Jun; Zhang, Jian-Song

    2006-07-01

    The present study was designed to investigate the role of bombesin receptor subtype 3 (BRS-3) in airway wound repair. The results showed that: (1) There was few expression of BRS-3 mRNA in the control group. In contrast, the expression of BRS-3 mRNA was gradually increased in the early 2 days, and peaked on the fourth day, and then decreased in the ozone-stressed AHR animal. BRS-3 mRNA was distributed in the ciliated columnar epithelium, monolayer columnar epithelium cells, scattered mesenchymal cells and Type II alveolar cells; (2) The wound repair and proliferation of bronchial epithelial cells (BECs) were accelerated in a concentration-dependent manner by BRS-3 activation with P3513, which could be inhibited by PKA inhibitor H89. The study demostrated that activation of BRS-3 may play an important role in wound repair of AHR.

  2. Erythropoietin reduces cumulative nephrotoxicity from cisplatin and enhances renal tubular cell proliferation.

    PubMed

    Zafirov, Dimce; Petrusevska, G; Sikole, Aleksandar; Trojacanec, J; Labacevski, N; Kostova, E; Jakovski, K; Atanasovska, E; Petrov, S

    2008-12-01

    Cisplatin, a heavy metal complex, is one of the most active drugs used in the treatment of several human malignancies. However, high-dose therapy with cisplatin is limited by its cumulative nephrotoxicity. The main objectives of this study were to determine the role of recombinant human erythropoietin (Epoetin alfa) in the prevention of nephrotoxicity induced experimentally in Wistar rats by long-term administration of cisplatin (2 mg/kg/b.w./week) over eight weeks, and an evaluation of its effect on renal tubular cell proliferation. The animals were randomly assigned into three groups, each including 25 rats. Group 1 (CP) received only cisplatin (2 mg/kg/b.w./week), group 2 (CP+EPO) received cisplatin (2 mg/kg/b.w./week) and epoetin alfa (150 IE/kg/b.w./three times a week), and group 3 (control group) received only saline. During the study, the following tests for the assessment of the renal function and renal damages were performed: determination of concentration of serum creatinine and BUN and determination of total protein quantity in 24-hour urine samples. At the end of the study, the abdomen was opened and both kidneys of the rats were removed and sent for histological and morphometric analysis. Ki-67 was used as a tool to determine a proliferative index. The results obtained have shown that epoetin alfa significantly reduced the functional renal failures and renal damages, and increased toleration of high doses of cisplatin. At the same time, our results with regard to tubular proliferative index have confirmed that one of the possible mechanisms by which erythropoietin accomplishes its renoprotective effect is stimulation of tubular cell proliferation and regeneration.

  3. Passive avoidance training enhances cell proliferation in 1-day-old chicks.

    PubMed

    Dermon, C R; Zikopoulos, B; Panagis, L; Harrison, E; Lancashire, C L; Mileusnic, R; Stewart, M G

    2002-10-01

    One-day-old domestic chicks were injected i.p. with bromodeoxyuridine (BrdU) before training on a one-trial passive avoidance task where the aversive experience was a bead coated with a bitter tasting substance, methyl anthranilate (MeA). Animals were tested 24 h later; those avoiding (if MeA-trained) or pecking if water (W)-trained (which they peck appetitively), along with a group of untrained naïve chicks, were used to determine cell proliferation either 24 h or 9 days post BrdU injection. In all three groups, BrdU positive cells were identified sparsely throughout the forebrain but labelling was pronounced around ventricular zone (VZ) surfaces at both 24 h and 9 days post-BrdU-injection. Double immunolabelling with neuronal specific antibodies, to either NeuN, or beta-tubulin III, confirmed that most BrdU labelled cells appeared to be neurons. Unbiased stereological analysis of labelled cells in selected forebrain areas 24 h post BrdU injection showed a significant MeA-training induced increase in labelled cells in both the dorsal VZ surface bordering the intermediate and medial hyperstriatum ventrale (IMHV) and the tuberculum olfactorium (TO). By 9 days post-BrdU-injection, there was a significantly greater number of BrdU labelled cells in MeA-trained birds within the IMHV, lobus parolfactorius (LPO) and TO. These results demonstrate that avoidance training in 1-day-old chicks has a marked effect on cell proliferation, in the LPO and IMHV, regions of the chick previously identified as a key loci of memory formation, and in a second region (TO), which has olfactory functions, but has not been previously investigated in relation to avoidance learning.

  4. The BMP signaling pathway leads to enhanced proliferation in serous ovarian cancer-A potential therapeutic target.

    PubMed

    Peng, Jin; Yoshioka, Yumiko; Mandai, Masaki; Matsumura, Noriomi; Baba, Tsukasa; Yamaguchi, Ken; Hamanishi, Junzo; Kharma, Budiman; Murakami, Ryusuke; Abiko, Kaoru; Murphy, Susan K; Konishi, Ikuo

    2016-04-01

    Members of the transforming growth factor-β (TGF-β) superfamily transduce signals via SMAD proteins. SMAD2 and SMAD3 mediate TGF-β signaling, whereas SMAD1, SMAD5, and SMAD8/9 transduce bone morphogenetic protein (BMP) signals. We would like to identify the function of BMP/SMAD5 signaling in serous ovarian cancer. The protein levels of total SMAD5 and phosphorylated SMAD5 (pSMAD5) were examined by immunohistochemical analysis using clinical serous ovarian cancer samples. Following treatment with either recombinant BMP2 (rBMP2) or Dorsomorphin (DM), western blotting was performed to observe pSMAD5 protein in the cytoplasm and the nucleus, separately. Cell proliferation was detected in SMAD5 knockdown serous ovarian cancer cell lines cultured with DM or rBMP2. The impact of DM or rBMP2 on tumor growth was observed in a mouse model of serous ovarian cancer. An inverse correlation was observed between pSMAD5 levels in the nucleus and the prognosis of patients with serous ovarian cancer. The treatment of SK-OV-3 with rBMP2 stimulated pSMAD5 translocation from the cytoplasm to the nucleus, and the addition of DM inhibited this effect. The proliferation of ovarian cancer cell lines was enhanced by BMP2 and suppressed by DM via SMAD5 in vitro. In vitro and in vivo experiments clearly demonstrated BMP2-stimulated proliferation of serous ovarian cancer and inhibition of this effect by DM. Our data suggests that BMP/SMAD5 signaling plays an important role and, therefore, becomes a potential therapeutic target in serous ovarian cancer. © 2015 Wiley Periodicals, Inc.

  5. Xenobiotic-induced hepatocyte proliferation associated with constitutive active/androstane receptor (CAR) or peroxisome proliferator-activated receptor α (PPARα) is enhanced by pregnane X receptor (PXR) activation in mice.

    PubMed

    Shizu, Ryota; Benoki, Satoshi; Numakura, Yuki; Kodama, Susumu; Miyata, Masaaki; Yamazoe, Yasushi; Yoshinari, Kouichi

    2013-01-01

    Xenobiotic-responsive nuclear receptors pregnane X receptor (PXR), constitutive active/androstane receptor (CAR) and peroxisome proliferator-activated receptor α (PPARα) play pivotal roles in the metabolic functions of the liver such as xenobiotics detoxification and energy metabolism. While CAR or PPARα activation induces hepatocyte proliferation and hepatocarcinogenesis in rodent models, it remains unclear whether PXR activation also shows such effects. In the present study, we have investigated the role of PXR in the xenobiotic-induced hepatocyte proliferation with or without CAR activation by 1,4-bis[2-(3,5-dichloropyridyloxy)]benzene (TCPOBOP) and phenobarbital, or PPARα activation by Wy-14643 in mice. Treatment with TCPOBOP or phenobarbital increased the percentage of Ki-67-positive nuclei as well as mRNA levels of cell proliferation-related genes in livers as expected. On the other hand, treatment with the PXR activator pregnenolone 16α-carbonitrile (PCN) alone showed no such effects. Surprisingly, PCN co-treatment significantly augmented the hepatocyte proliferation induced by CAR activation with TCPOBOP or phenobarbital in wild-type mice but not in PXR-deficient mice. Intriguingly, PXR activation also augmented the hepatocyte proliferation induced by Wy-14643 treatment. Moreover, PCN treatment increased the RNA content of hepatocytes, suggesting the induction of G0/G1 transition, and reduced mRNA levels of Cdkn1b and Rbl2, encoding suppressors of cell cycle initiation. Our present findings indicate that xenobiotic-induced hepatocyte proliferation mediated by CAR or PPARα is enhanced by PXR co-activation despite that PXR activation alone does not cause the cell proliferation in mouse livers. Thus PXR may play a novel and unique role in the hepatocyte/liver hyperplasia upon exposure to xenobiotics.

  6. HTLV-1 bZIP Factor Enhances T-Cell Proliferation by Impeding the Suppressive Signaling of Co-inhibitory Receptors

    PubMed Central

    Shimura, Kazuya; Onishi, Chiho; Iyoda, Tomonori; Inaba, Kayo

    2017-01-01

    Human T-cell leukemia virus type 1 (HTLV-1) causes adult T-cell leukemia-lymphoma (ATL) and inflammatory diseases. To enhance cell-to-cell transmission of HTLV-1, the virus increases the number of infected cells in vivo. HTLV-1 bZIP factor (HBZ) is constitutively expressed in HTLV-1 infected cells and ATL cells and promotes T-cell proliferation. However, the detailed mechanism by which it does so remains unknown. Here, we show that HBZ enhances the proliferation of expressing T cells after stimulation via the T-cell receptor. HBZ promotes this proliferation by influencing the expression and function of multiple co-inhibitory receptors. HBZ suppresses the expression of BTLA and LAIR-1 in HBZ expressing T cells and ATL cells. Expression of T cell immunoglobulin and ITIM domain (TIGIT) and Programmed cell death 1 (PD-1) was enhanced, but their suppressive effect on T-cell proliferation was functionally impaired. HBZ inhibits the co-localization of SHP-2 and PD-1 in T cells, thereby leading to impaired inhibition of T-cell proliferation and suppressed dephosphorylation of ZAP-70 and CD3ζ. HBZ does this by interacting with THEMIS, which associates with Grb2 and SHP-2. Thus, HBZ interacts with the SHP containing complex, impedes the suppressive signal from PD-1 and TIGIT, and enhances the proliferation of T cells. Although HBZ was present in both the nucleus and the cytoplasm of T cells, HBZ was localized largely in the nucleus by suppressed expression of THEMIS by shRNA. This indicates that THEMIS is responsible for cytoplasmic localization of HBZ in T cells. Since THEMIS is expressed only in T-lineage cells, HBZ mediated inhibition of the suppressive effects of co-inhibitory receptors accounts for how HTLV-1 induces proliferation only of T cells in vivo. This study reveals that HBZ targets co-inhibitory receptors to cause the proliferation of infected cells. PMID:28046066

  7. Cannabidiol enhances the inhibitory effects of Δ9-tetrahydrocannabinol on human glioblastoma cell proliferation and survival

    PubMed Central

    Marcu, Jahan P.; Christian, Rigel T.; Lau, Darryl; Zielinski, Anne J.; Horowitz, Maxx P.; Lee, Jasmine; Pakdel, Arash; Allison, Juanita; Limbad, Chandani; Moore, Dan H.; Yount, Garret L.; Desprez, Pierre-Yves; McAllister, Sean D.

    2009-01-01

    The cannabinoid 1 (CB1) and cannabinoid 2 (CB2) receptor agonist, Δ9-tetrahydrocannabinol (THC), has been shown to be a broad range inhibitor of cancer in culture and in vivo, and is currently being used in a clinical trial for the treatment of glioblastoma. It has been suggested that other plant-derived cannabinoids, which do not interact efficiently with CB1 and CB2 receptors, can modulate the actions of Δ9-THC. However, there are conflicting reports as to what extent other cannabinoids can modulate Δ9-THC activity, and most importantly, it is not clear whether other cannabinoid compounds can either potentiate or inhibit the actions of Δ9-THC. We therefore tested cannabidiol (CBD), the second most abundant plant derived cannabiniod, in combination with Δ9-THC. In U251 and SF126 glioblastoma cell lines, Δ9-THC and CBD acted synergistically to inhibit cell proliferation. The treatment of glioblastoma cells with both compounds led to significant modulations of the cell cycle and induction of reactive oxygen species (ROS) and apoptosis as well as specific modulations of extracellular signal-regulated kinase (ERK) and caspase activities. These specific changes were not observed with either compound individually, indicating that the signal transduction pathways affected by the combination treatment were unique. Our results suggest that the addition of CBD to Δ9-THC may improve the overall effectiveness of Δ9-THC in the treatment of glioblastoma in cancer patients. PMID:20053780

  8. Andrographolide enhances proliferation and prevents dedifferentiation of rabbit articular chondrocytes: an in vitro study.

    PubMed

    Luo, Li-Ke; Wei, Qing-Jun; Liu, Lei; Zheng, Li; Zhao, Jin-Min

    2015-01-01

    As the main active constituent of Andrographis paniculata that was applied in treatment of many diseases including inflammation in ancient China, andrographolide (ANDRO) was found to facilitate reduction of edema and analgesia in arthritis. This suggested that ANDRO may be promising anti-inflammatory agent to relieve destruction and degeneration of cartilage after inflammation. In this study, the effect of ANDRO on rabbit articular chondrocytes in vitro was investigated. Results showed that not more than 8 μM ANDRO did no harm to chondrocytes (P < 0.05). DNA content and glycosaminoglycan (GAG) /DNA were, respectively, improved in ANDRO groups comparing to the control (P < 0.05). ANDRO could promote expression of aggrecan, collagen II, and Sox9 genes while downregulating expression of collagen I gene (P < 0.05). Furthermore, hypertrophy that may result in chondrocyte ossification could not be detected in all groups (P > 0.05). The viability assay, hematoxylin-eosin, safranin O, and immunohistochemical staining also showed better performances in ANDRO groups. As to the doses, 3 μM ANDRO showed the best performance. The results indicate that ANDRO can accelerate proliferation of rabbit articular chondrocytes in vitro and meanwhile maintain the phenotype, which may provide valuable references for further exploration on arthritis.

  9. Hydrophilic PCU scaffolds prepared by grafting PEGMA and immobilizing gelatin to enhance cell adhesion and proliferation.

    PubMed

    Shi, Changcan; Yuan, Wenjie; Khan, Musammir; Li, Qian; Feng, Yakai; Yao, Fanglian; Zhang, Wencheng

    2015-05-01

    Gelatin contains many functional motifs which can modulate cell specific adhesion, so we modified polycarbonate urethane (PCU) scaffold surface by immobilization of gelatin. PCU-g-gelatin scaffolds were prepared by direct immobilizing gelatins onto the surface of aminated PCU scaffolds. To increase the immobilization amount of gelatin, poly(ethylene glycol) methacrylate (PEGMA) was grafted onto PCU scaffolds by surface initiated atom transfer radical polymerization. Then, following amination and immobilization, PCU-g-PEGMA-g-gelatin scaffolds were obtained. Both modified scaffolds were characterized by chemical and biological methods. After immobilization of gelatin, the microfiber surface became rough, but the original morphology of scaffolds was maintained successfully. PCU-g-PEGMA-g-gelatin scaffolds were more hydrophilic than PCU-g-gelatin scaffolds. Because hydrophilic PEGMA and gelatin were grafted and immobilized onto the surface, the PCU-g-PEGMA-g-gelatin scaffolds showed low platelet adhesion, perfect anti-hemolytic activity and excellent cell growth and proliferation capacity. It could be envisioned that PCU-g-PEGMA-g-gelatin scaffolds might have potential applications in tissue engineering artificial scaffolds.

  10. Chemical surface modification of parylene C for enhanced protein immobilization and cell proliferation.

    PubMed

    Zhang, Changhong; Thompson, Mark E; Markland, Frank S; Swenson, Steve

    2011-10-01

    To introduce the adhesion site of proteins and/or cells on parylene C (PC)-coated medical devices that can be used as implantable biosensors or drug delivery capsules, the PC surfaces were initially modified by the Friedel-Crafts acylation reaction to generate active chlorines. These chlorines were then employed to initiate the atom transfer radical polymerization of tert-butyl acrylate (TBA) and form a polymer brush layer of polyTBA on PC; the acrylate groups in the polymer brushes were hydrolyzed to carboxylic acid groups and further activated into succinimidyl ester groups via the 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide/N-hydroxysuccinimide coupling reaction. The PC surface grafted with polymer brushes and activated by succinimide showed efficient attachment of proteins, including gelatin, contortrostatin (CN) and bovine serum albumin (BSA), all at high density on the PC surface. The CN density on the surface was evaluated for both monolayer and polymer brush-based coatings. Based on fluorescence measurements, the polymer brush gives a 60-fold higher surface protein density than the monolayer-based system. Gelatin was used as a model protein and covalently coated onto the modified PC surface for cell culture study. Substrates with gelatin coating showed a significantly higher cell attachment and proliferation in 7 days cultures as compared to the uncoated substrates. In addition, a conventional photolithography technique was coupled with the surface chemistry to successfully pattern the BSA labeled with fluorescein isothiocyanate on the modified PC surfaces.

  11. Hispidulin inhibits proliferation and enhances chemosensitivity of gallbladder cancer cells by targeting HIF-1α

    SciTech Connect

    Gao, Hui; Xie, Jing; Peng, Jianjun; Han, Yantao; Jiang, Qixiao; Han, Mei; Wang, Chunbo

    2015-03-15

    Gallbladder cancer (GBC) is an aggressive malignancy of the bile duct, which is associated with a low (5-year) survival and poor prognosis. The transcription factor HIF-1α is implicated in the angiogenesis, cell survival, epithelial mesenchymal transition (EMT) and invasiveness of GBC. In this study, we have investigated the role of HIF-1α in the pathobilogy of GBC and effect of hispidulin on the molecular events controlled by this transcription factor. We observed that hispidulin caused induction of apoptosis, blockade of growth and cell cycle progression in GBC cells. Our results have demonstrated for the first time that hispidulin-exerted anti-tumor effect involved the suppression of HIF-1α signaling. Hispidulin was found to repress the expression of HIF-1α protein dose-dependently without affecting the HIF-1α mRNA expression. In addition, the inhibition of HIF-1α protein synthesis was revealed to be mediated through the activation of AMPK signaling. Hispidulin also sensitized the tumor cells to Gemcitabine and 5-Fluoroucil by down-regulating HIF-1α/P-gp signaling. Given the low cost and exceedingly safe profile, hispidulin appears to be a promising and novel chemosensitizer for GBC treatment. - Highlights: • Hispidulin inhibits proliferation of gallbladder cancer cells by targeting HIF-1α. • Hispidulin regulates HIF-1α via activating AMPK signaling. • Hispidulin sensitized the GBC cells to chemotherapeutics by down-regulating P-gp.

  12. Surface tailored organobentonite enhances bacterial proliferation and phenanthrene biodegradation under cadmium co-contamination.

    PubMed

    Mandal, Asit; Biswas, Bhabananda; Sarkar, Binoy; Patra, Ashok K; Naidu, Ravi

    2016-04-15

    Co-contamination of soil and water with polycyclic aromatic hydrocarbon (PAH) and heavy metals makes biodegradation of the former extremely challenging. Modified clay-modulated microbial degradation provides a novel insight in addressing this issue. This study was conducted to evaluate the growth and phenanthrene degradation performance of Mycobacterium gilvum VF1 in the presence of a palmitic acid (PA)-grafted Arquad® 2HT-75-based organobentonite in cadmium (Cd)-phenanthrene co-contaminated water. The PA-grafted organobentonite (ABP) adsorbed a slightly greater quantity of Cd than bentonite at up to 30mgL(-1) metal concentration, but its highly negative surface charge imparted by carboxylic groups indicated the potential of being a significantly superior adsorbent of Cd at higher metal concentrations. In systems co-contained with Cd (5 and 10mgL(-1)), the Arquad® 2HT-75-modified bentonite (AB) and PA-grafted organobentonite (ABP) resulted in a significantly higher (72-78%) degradation of phenanthrene than bentonite (62%) by the bacterium. The growth and proliferation of bacteria were supported by ABP which not only eliminated Cd toxicity through adsorption but also created a congenial microenvironment for bacterial survival. The macromolecules produced during ABP-bacteria interaction could form a stable clay-bacterial cluster by overcoming the electrostatic repulsion among individual components. Findings of this study provide new insights for designing clay modulated PAH bioremediation technologies in mixed-contaminated water and soil.

  13. Andrographolide Enhances Proliferation and Prevents Dedifferentiation of Rabbit Articular Chondrocytes: An In Vitro Study

    PubMed Central

    Luo, Li-ke; Wei, Qing-jun; Liu, Lei; Zheng, Li; Zhao, Jin-min

    2015-01-01

    As the main active constituent of Andrographis paniculata that was applied in treatment of many diseases including inflammation in ancient China, andrographolide (ANDRO) was found to facilitate reduction of edema and analgesia in arthritis. This suggested that ANDRO may be promising anti-inflammatory agent to relieve destruction and degeneration of cartilage after inflammation. In this study, the effect of ANDRO on rabbit articular chondrocytes in vitro was investigated. Results showed that not more than 8 μM ANDRO did no harm to chondrocytes (P < 0.05). DNA content and glycosaminoglycan (GAG) /DNA were, respectively, improved in ANDRO groups comparing to the control (P < 0.05). ANDRO could promote expression of aggrecan, collagen II, and Sox9 genes while downregulating expression of collagen I gene (P < 0.05). Furthermore, hypertrophy that may result in chondrocyte ossification could not be detected in all groups (P > 0.05). The viability assay, hematoxylin-eosin, safranin O, and immunohistochemical staining also showed better performances in ANDRO groups. As to the doses, 3 μM ANDRO showed the best performance. The results indicate that ANDRO can accelerate proliferation of rabbit articular chondrocytes in vitro and meanwhile maintain the phenotype, which may provide valuable references for further exploration on arthritis. PMID:25802548

  14. Peroxisome proliferator-activated receptor γ enhances adiponectin secretion via up-regulating DsbA-L expression.

    PubMed

    Jin, Dan; Sun, Jun; Huang, Jing; Yu, Xiaoling; Yu, An; He, Yiduo; Li, Qiang; Yang, Zaiqing

    2015-08-15

    Disulfide-bond A oxidoreductase like-protein (DsbA-L) was identified as a molecular chaperone facilitating the assembly and secretion of adiponectin, an adipokine with multiple beneficial effects. In obesity the level of DsbA-L is reduced with a concomitant decrease of the circulating adiponectin level, especially of the high molecular weight form (HMW). Both rodent and human studies have shown that the nuclear receptor peroxisome proliferator-activated receptor (PPAR)-γ agonists increase adiponectin levels in serum by activating PPARγ, which up-regulates critical endoplasmic reticulum (ER) chaperones thus facilitating protein folding. As shown in the present study, overexpression of PPARγ in human embryonic kidney (HEK) 293 cells elicited the cellular release of HMW adiponectin. PPARγ enhanced expression of DsbA-L by binding directly to peroxisome proliferator response element (PPRE) site within the DsbA-L promoter. Conversely, in differentiated 3T3-L1 cells, PPARγ knockdown resulted in decreased expression of Adiponectin, DsbA-L and ERp44. DsbA-L expression increased after PPARγ agonist treatment and decreased upon treatment with PPARγ antagonist in 3T3-L1 adipocytes. DsbA-L deficiency in differentiated 3T3-L1 cells impaired the secretion of adiponectin. We therefore propose that DsbA-L plays an important role in facilitating HMW adiponectin formation and release from cells under the regulation of PPARγ.

  15. Mimicking bone extracellular matrix: integrin-binding peptidomimetics enhance osteoblast-like cells adhesion, proliferation, and differentiation on titanium.

    PubMed

    Fraioli, Roberta; Rechenmacher, Florian; Neubauer, Stefanie; Manero, José M; Gil, Javier; Kessler, Horst; Mas-Moruno, Carlos

    2015-04-01

    Interaction between the surface of implants and biological tissues is a key aspect of biomaterials research. Apart from fulfilling the non-toxicity and structural requirements, synthetic materials are asked to direct cell response, offering engineered cues that provide specific instructions to cells. This work explores the functionalization of titanium with integrin-binding peptidomimetics as a novel and powerful strategy to improve the adhesion, proliferation and differentiation of osteoblast-like cells to implant materials. Such biomimetic strategy aims at targeting integrins αvβ3 and α5β1, which are highly expressed on osteoblasts and are essential for many fundamental functions in bone tissue development. The successful grafting of the bioactive molecules on titanium is proven by contact angle measurements, X-ray photoelectron spectroscopy and fluorescent labeling. Early attachment and spreading of cells are statistically enhanced by both peptidomimetics compared to unmodified titanium, reaching values of cell adhesion comparable to those obtained with full-length extracellular matrix proteins. Moreover, an increase in alkaline phosphatase activity, and statistically higher cell proliferation and mineralization are observed on surfaces coated with the peptidomimetics. This study shows an unprecedented biological activity for low-molecular-weight ligands on titanium, and gives striking evidence of the potential of these molecules to foster bone regeneration on implant materials.

  16. Porous titania surfaces on titanium with hierarchical macro- and mesoporosities for enhancing cell adhesion, proliferation and mineralization.

    PubMed

    Han, Guang; Müller, Werner E G; Wang, Xiaohong; Lilja, Louise; Shen, Zhijian

    2015-02-01

    Titanium received a macroporous titania surface layer by anodization, which contains open pores with average pore diameter around 5 μm. An additional mesoporous titania top layer following the contour of the macropores, of 100-200 nm thickness and with a pore diameter of 10nm, was formed by using the evaporation-induced self-assembly (EISA) method with titanium (IV) tetraethoxide as the precursor. A coherent laminar titania surface layer was thus obtained, creating a hierarchical macro- and mesoporous surface that was characterized by high-resolution electron microscopy. The interfacial bonding between the surface layers and the titanium matrix was characterized by the scratch test that confirmed a stable and strong bonding of titania surface layers on titanium. The wettability to water and the effects on the osteosarcoma cell line (SaOS-2) proliferation and mineralization of the formed titania surface layers were studied systematically by cell culture and scanning electron microscopy. The results proved that the porous titania surface with hierarchical macro- and mesoporosities was hydrophilic that significantly promoted cell attachment and spreading. A synergistic role of the hierarchical macro- and mesoporosities was revealed in terms of enhancing cell adhesion, proliferation and mineralization, compared with the titania surface with solo scale topography.

  17. T3 enhances thyroid cancer cell proliferation through TRβ1/Oct-1-mediated cyclin D1 activation.

    PubMed

    Perri, Anna; Catalano, Stefania; Bonofiglio, Daniela; Vizza, Donatella; Rovito, Daniela; Qi, Hongyan; Aquila, Saveria; Panza, Salvatore; Rizza, Pietro; Lanzino, Marilena; Andò, Sebastiano

    2014-01-25

    Several studies have demonstrated that thyroid hormone T3 promotes cancer cell growth, even though the molecular mechanism involved in such processes still needs to be elucidated. In this study we demonstrated that T3 induced proliferation in papillary thyroid carcinoma cell lines concomitantly with an up-regulation of cyclin D1 expression, that is a critical mitogen-regulated cell-cycle control element. Our data revealed that T3 enhanced the recruitment of the TRβ1/Oct-1 complex on Octamer-transcription factor-1 site within cyclin D1 promoter, leading to its transactivation. In addition, silencing of TRβ1 or Oct-1 expression by RNA interference reversed both increased cell proliferation and up-regulation of cyclin D1, underlying the important role of both transcriptional factors in mediating these effects. Finally, T3-induced increase in cell growth was abrogated after knocking down cyclin D1 expression. All these findings highlight a new molecular mechanism by which T3 promotes thyroid cancer cell growth.

  18. Enhanced Rb/E2F and TSC/mTOR Pathways Induce Synergistic Inhibition in PDGF-Induced Proliferation in Vascular Smooth Muscle Cells.

    PubMed

    Li, Yue; Li, Xuan; Liu, Jie; Guo, Wei; Zhang, Hongchao; Wang, Jianchang

    2017-01-01

    Platelet-derived growth factor (PDGF) plays an essential role in proliferation of vascular smooth muscle cells (VSMCs). The Rb/E2F and TSC/mTOR pathways contribute to the proliferation of VSMCs, but its exact roles in PDGF-induced proliferation are unclear. In this study, we demonstrated the roles of Rb/E2F and TSC/mTOR pathways in PDGF-induced proliferation in VSMCs. We found that PDGF stimulates the activity of E2F and mTOR pathways, and knockdown of either Rb or TSC2 increases PDGF-induced proliferation in VSMCs. More interestingly, we revealed that enhancing both E2F and mTOR activity leads to synergistic inhibition of PDGF-induced proliferation in VSMCs. We further identified that the synergistic inhibition effect is caused by the induced oxidative stress. Summarily, these data suggest the important regulations of Rb/E2F and TSC/mTOR pathways in PDGF-induced proliferation in VSMCs, and also present a promising way to limit deregulated proliferation by PDGF induction in VSMCs.

  19. Enhanced Rb/E2F and TSC/mTOR Pathways Induce Synergistic Inhibition in PDGF-Induced Proliferation in Vascular Smooth Muscle Cells

    PubMed Central

    Liu, Jie; Guo, Wei; Zhang, Hongchao; Wang, Jianchang

    2017-01-01

    Platelet-derived growth factor (PDGF) plays an essential role in proliferation of vascular smooth muscle cells (VSMCs). The Rb/E2F and TSC/mTOR pathways contribute to the proliferation of VSMCs, but its exact roles in PDGF-induced proliferation are unclear. In this study, we demonstrated the roles of Rb/E2F and TSC/mTOR pathways in PDGF-induced proliferation in VSMCs. We found that PDGF stimulates the activity of E2F and mTOR pathways, and knockdown of either Rb or TSC2 increases PDGF-induced proliferation in VSMCs. More interestingly, we revealed that enhancing both E2F and mTOR activity leads to synergistic inhibition of PDGF-induced proliferation in VSMCs. We further identified that the synergistic inhibition effect is caused by the induced oxidative stress. Summarily, these data suggest the important regulations of Rb/E2F and TSC/mTOR pathways in PDGF-induced proliferation in VSMCs, and also present a promising way to limit deregulated proliferation by PDGF induction in VSMCs. PMID:28076433

  20. Overexpression of FABP3 inhibits human bone marrow derived mesenchymal stem cell proliferation but enhances their survival in hypoxia

    SciTech Connect

    Wang, Suna Zhou, Yifu; Andreyev, Oleg; Hoyt, Robert F.; Singh, Avneesh; Hunt, Timothy; Horvath, Keith A.

    2014-04-15

    Studying the proliferative ability of human bone marrow derived mesenchymal stem cells in hypoxic conditions can help us achieve the effective regeneration of ischemic injured myocardium. Cardiac-type fatty acid binding protein (FABP3) is a specific biomarker of muscle and heart tissue injury. This protein is purported to be involved in early myocardial development, adult myocardial tissue repair and responsible for the modulation of cell growth and proliferation. We have investigated the role of FABP3 in human bone marrow derived mesenchymal stem cells under ischemic conditions. MSCs from 12 donors were cultured either in standard normoxic or modified hypoxic conditions, and the differential expression of FABP3 was tested by quantitative {sup RT}PCR and western blot. We also established stable FABP3 expression in MSCs and searched for variation in cellular proliferation and differentiation bioprocesses affected by hypoxic conditions. We identified: (1) the FABP3 differential expression pattern in the MSCs under hypoxic conditions; (2) over-expression of FABP3 inhibited the growth and proliferation of the MSCs; however, improved their survival in low oxygen environments; (3) the cell growth factors and positive cell cycle regulation genes, such as PCNA, APC, CCNB1, CCNB2 and CDC6 were all down-regulated; while the key negative cell cycle regulation genes TP53, BRCA1, CASP3 and CDKN1A were significantly up-regulated in the cells with FABP3 overexpression. Our data suggested that FABP3 was up-regulated under hypoxia; also negatively regulated the cell metabolic process and the mitotic cell cycle. Overexpression of FABP3 inhibited cell growth and proliferation via negative regulation of the cell cycle and down-regulation of cell growth factors, but enhances cell survival in hypoxic or ischemic conditions. - Highlights: • FABP3 expression pattern was studied in 12 human hypoxic-MSCs. • FABP3 mRNA and proteins are upregulated in the MSCs under hypoxic conditions.

  1. 10-Shogaol, an Antioxidant from Zingiber officinale for Skin Cell Proliferation and Migration Enhancer

    PubMed Central

    Chen, Chung-Yi; Cheng, Kuo-Chen; Chang, Andy Y; Lin, Ying-Ting; Hseu, You-Cheng; Wang, Hui-Min

    2012-01-01

    In this work, one of Zingiber officinale components, 10-shogaol, was tested with 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging, metal chelating ability, and reducing power to show antioxidant activity. 10-Shogaol promoted human normal epidermal keratinocytes and dermal fibroblasts cell growths. 10-Shogaol enhanced growth factor production in transforming growth factor-β (TGF-β), platelet derived growth factor-αβ (PDGF-αβ) and vascular endothelial growth factors (VEGF) of both cells. In the in vitro wound healing assay for 12 or 24 h, with 10-shogaol, the fibroblasts and keratinocytes migrated more rapidly than the vehicle control group. Thus, this study substantiates the target compound, 10-shogaol, as an antioxidant for human skin cell growth and a migration enhancer with potential to be a novel wound repair agent. PMID:22408422

  2. Boric acid enhances in vivo Ehrlich ascites carcinoma cell proliferation in Swiss albino mice.

    PubMed

    Qureshi, S; Al-Shabanah, O A; Al-Harbi, M M; Al-Bekairi, A M; Raza, M

    2001-08-13

    The influence of boric acid, a boron carrier, on Ehrlich ascites carcinoma (EAC) cell-bearing mice was investigated in view of its importance in the boron neutron capture therapy and the influence of boron on proliferation and progression of cancer cells mediated by proteoglycans and collagen. The present study included the evaluation of boric acid for the effects on total count and viability of EAC cells in addition to their non-protein sulfhydryls (NP-SH) and malondialdehyde (MDA) contents as parameters for conjugative detoxication potency and possible oxidative damage. The EAC cell-bearing animals were also observed for the effect on survival, body weight changes, and histopathological evaluation of the tumors grown at the site of inoculation. The treatment with boric acid significantly increased the total number of peritoneal EAC cells and their viability. A significant increase in the body weight was observed that dose-dependently reached plateau levels by 20 days of treatment. Conversely, a reduction in the duration of survival of these animals was evident with the same protocol. Boric acid treatment resulted in a decrease in NP-SH contents with a concomitant increase in MDA levels in EAC cells as revealed by the results of the biochemical analysis. These data are supported by our results on histopathological investigations, which apparently showed fast growth, in addition to several mitotic figures and mixed inflammatory reaction, after treatment with boric acid. It seems likely that a particular combination of properties of boric acid, rather than a single characteristic alone, will provide useful information on the use of this boron carrier in neutron capture therapy.

  3. MicroRNA-132 enhances transition from inflammation to proliferation during wound healing.

    PubMed

    Li, Dongqing; Wang, Aoxue; Liu, Xi; Meisgen, Florian; Grünler, Jacob; Botusan, Ileana R; Narayanan, Sampath; Erikci, Erdem; Li, Xi; Blomqvist, Lennart; Du, Lei; Pivarcsi, Andor; Sonkoly, Enikö; Chowdhury, Kamal; Catrina, Sergiu-Bogdan; Ståhle, Mona; Landén, Ning Xu

    2015-08-03

    Wound healing is a complex process that is characterized by an initial inflammatory phase followed by a proliferative phase. This transition is a critical regulatory point; however, the factors that mediate this process are not fully understood. Here, we evaluated microRNAs (miRs) in skin wound healing and characterized the dynamic change of the miRNome in human skin wounds. miR-132 was highly upregulated during the inflammatory phase of wound repair, predominantly expressed in epidermal keratinocytes, and peaked in the subsequent proliferative phase. TGF-β1 and TGF-β2 induced miR-132 expression in keratinocytes, and transcriptome analysis of these cells revealed that miR-132 regulates a large number of immune response- and cell cycle-related genes. In keratinocytes, miR-132 decreased the production of chemokines and the capability to attract leukocytes by suppressing the NF-κB pathway. Conversely, miR-132 increased activity of the STAT3 and ERK pathways, thereby promoting keratinocyte growth. Silencing of the miR-132 target heparin-binding EGF-like growth factor (HB-EGF) phenocopied miR-132 overexpression in keratinocytes. Using mouse and human ex vivo wound models, we found that miR-132 blockade delayed healing, which was accompanied by severe inflammation and deficient keratinocyte proliferation. Together, our results indicate that miR-132 is a critical regulator of skin wound healing that facilitates the transition from the inflammatory to the proliferative phase.

  4. Sex hormone-dependent tRNA halves enhance cell proliferation in breast and prostate cancers.

    PubMed

    Honda, Shozo; Loher, Phillipe; Shigematsu, Megumi; Palazzo, Juan P; Suzuki, Ryusuke; Imoto, Issei; Rigoutsos, Isidore; Kirino, Yohei

    2015-07-21

    Sex hormones and their receptors play critical roles in the development and progression of the breast and prostate cancers. Here we report that a novel type of transfer RNA (tRNA)-derived small RNA, termed Sex HOrmone-dependent TRNA-derived RNAs (SHOT-RNAs), are specifically and abundantly expressed in estrogen receptor (ER)-positive breast cancer and androgen receptor (AR)-positive prostate cancer cell lines. SHOT-RNAs are not abundantly present in ER(-) breast cancer, AR(-) prostate cancer, or other examined cancer cell lines from other tissues. ER-dependent accumulation of SHOT-RNAs is not limited to a cell culture system, but it also occurs in luminal-type breast cancer patient tissues. SHOT-RNAs are produced from aminoacylated mature tRNAs by angiogenin-mediated anticodon cleavage, which is promoted by sex hormones and their receptors. Resultant 5'- and 3'-SHOT-RNAs, corresponding to 5'- and 3'-tRNA halves, bear a cyclic phosphate (cP) and an amino acid at the 3'-end, respectively. By devising a "cP-RNA-seq" method that is able to exclusively amplify and sequence cP-containing RNAs, we identified the complete repertoire of 5'-SHOT-RNAs. Furthermore, 5'-SHOT-RNA, but not 3'-SHOT-RNA, has significant functional involvement in cell proliferation. These results have unveiled a novel tRNA-engaged pathway in tumorigenesis of hormone-dependent cancers and implicate SHOT-RNAs as potential candidates for biomarkers and therapeutic targets.

  5. Sex hormone-dependent tRNA halves enhance cell proliferation in breast and prostate cancers

    PubMed Central

    Honda, Shozo; Loher, Phillipe; Shigematsu, Megumi; Palazzo, Juan P.; Suzuki, Ryusuke; Imoto, Issei; Rigoutsos, Isidore; Kirino, Yohei

    2015-01-01

    Sex hormones and their receptors play critical roles in the development and progression of the breast and prostate cancers. Here we report that a novel type of transfer RNA (tRNA)-derived small RNA, termed Sex HOrmone-dependent TRNA-derived RNAs (SHOT-RNAs), are specifically and abundantly expressed in estrogen receptor (ER)-positive breast cancer and androgen receptor (AR)-positive prostate cancer cell lines. SHOT-RNAs are not abundantly present in ER− breast cancer, AR− prostate cancer, or other examined cancer cell lines from other tissues. ER-dependent accumulation of SHOT-RNAs is not limited to a cell culture system, but it also occurs in luminal-type breast cancer patient tissues. SHOT-RNAs are produced from aminoacylated mature tRNAs by angiogenin-mediated anticodon cleavage, which is promoted by sex hormones and their receptors. Resultant 5′- and 3′-SHOT-RNAs, corresponding to 5′- and 3′-tRNA halves, bear a cyclic phosphate (cP) and an amino acid at the 3′-end, respectively. By devising a “cP-RNA-seq” method that is able to exclusively amplify and sequence cP-containing RNAs, we identified the complete repertoire of 5′-SHOT-RNAs. Furthermore, 5′-SHOT-RNA, but not 3′-SHOT-RNA, has significant functional involvement in cell proliferation. These results have unveiled a novel tRNA-engaged pathway in tumorigenesis of hormone-dependent cancers and implicate SHOT-RNAs as potential candidates for biomarkers and therapeutic targets. PMID:26124144

  6. Mild heat stress enhances differentiation and proliferation of Japanese quail myoblasts and enhances slow muscle fiber characteristics.

    PubMed

    Choi, Y M; Chen, P R; Shin, S; Zhang, J; Hwang, S; Lee, K

    2016-08-01

    The objective of this study was to investigate the effect of mild heat stress on muscle fiber hyperplastic and hypertrophic growth in quail primary myogenic cells to better understand the mechanisms leading to increased skeletal muscle development in avian embryos incubated at a higher temperature. Compared to control cultures maintained at 37°C, incubation at 39°C enhanced myotube length (P < 0.01) and diameter (P < 0.001) at 3 days after differentiation (D3). This enlargement of the myotubes incubated at 39°C can be explained by differences in the fusion index (56.7 vs. 46.2%, P < 0.05) and nuclei number per myotube (18.1 vs. 10.8, P < 0.001) compared to the control cells at D3. Additionally, a higher density of myotubes at D3 in cultures exposed to a higher temperature were related to higher levels of Pax-7 (P < 0.05) compared to the control cells incubated continuously at 37°C. These results indicated a higher proliferative capacity in cells exposed to mild heat stress compared to the control cells. On the other hand, mild heat stress enhanced protein levels of slow myosin heavy chain isoform (P < 0.01) and cytochrome c oxidase subunit IV (P < 0.01) compared to the control cells at D3. These discrepancies in protein expression indicated maintenance of slow muscle fiber type characteristics in myotubes incubated at 39°C. Our results suggest that mild heat stress plays a significant role in myogenic mechanisms related to muscle mass and development.

  7. Activation of peroxisome proliferator-activated receptor-{alpha} enhances fatty acid oxidation in human adipocytes

    SciTech Connect

    Lee, Joo-Young; Hashizaki, Hikari; Goto, Tsuyoshi; Sakamoto, Tomoya; Takahashi, Nobuyuki; Kawada, Teruo

    2011-04-22

    Highlights: {yields} PPAR{alpha} activation increased mRNA expression levels of adipocyte differentiation marker genes and GPDH activity in human adipocytes. {yields} PPAR{alpha} activation also increased insulin-dependent glucose uptake in human adipocytes. {yields} PPAR{alpha} activation did not affect lipid accumulation in human adipocytes. {yields} PPAR{alpha} activation increased fatty acid oxidation through induction of fatty acid oxidation-related genes in human adipocytes. -- Abstract: Peroxisome proliferator-activated receptor-{alpha} (PPAR{alpha}) is a key regulator for maintaining whole-body energy balance. However, the physiological functions of PPAR{alpha} in adipocytes have been unclarified. We examined the functions of PPAR{alpha} using human multipotent adipose tissue-derived stem cells as a human adipocyte model. Activation of PPAR{alpha} by GW7647, a potent PPAR{alpha} agonist, increased the mRNA expression levels of adipocyte differentiation marker genes such as PPAR{gamma}, adipocyte-specific fatty acid-binding protein, and lipoprotein lipase and increased both GPDH activity and insulin-dependent glucose uptake level. The findings indicate that PPAR{alpha} activation stimulates adipocyte differentiation. However, lipid accumulation was not changed, which is usually observed when PPAR{gamma} is activated. On the other hand, PPAR{alpha} activation by GW7647 treatment induced the mRNA expression of fatty acid oxidation-related genes such as CPT-1B and AOX in a PPAR{alpha}-dependent manner. Moreover, PPAR{alpha} activation increased the production of CO{sub 2} and acid soluble metabolites, which are products of fatty acid oxidation, and increased oxygen consumption rate in human adipocytes. The data indicate that activation of PPAR{alpha} stimulates both adipocyte differentiation and fatty acid oxidation in human adipocytes, suggesting that PPAR{alpha} agonists could improve insulin resistance without lipid accumulation in adipocytes. The expected

  8. Proliferation enhancement of budding yeast and mammalian cells with periodic oxygen radical treatment

    NASA Astrophysics Data System (ADS)

    Mori, Yosuke; Kobayashi, Jun; Murata, Tomiyasu; Hahizume, Hiroshi; Hori, Masaru; Ito, Masafumi

    2015-09-01

    Recently, nonequilibrium atmospheric-pressure plasmas have been intensively studied for biological applications. However, the each effect of species in plasmas to biological tissue has not been clarified yet because various factors exist in the plasmas. Accordingly, we have studied effects of atomic oxygen dose on cell growth such as budding yeast and mouse NIH3T3 fibroblasts of mammalian cells. Both of cells were suspended with PBS, and treated using oxygen radical source. In order to prevent the radicals from reacting with the ambient air, the treatment region was surrounded by a plastic cover and purged with Ar. The proliferative effect of 15 % was observed at the O3Pj dose of around 1 . 0 ×1017 cm-3 in NIH3T3 cells as well as in yeast cells. Moreover, periodic oxygen treatment enhanced the effect in budding yeast cells. The best interval of periodic oxygen radical treatment was around 2 hours, which is almost the same period as that of their cell cycle. With the optimum interval time, we have investigated the effect of the number of the treatments. As the number of treatments increases, the growth rate of budding yeast cells was gradually enhanced and saturated at thrice treatments. This work was partly supported by JSPS KAKENHI Grant Numbers 26286072 and project for promoting Research Center in Meijo University.

  9. Enhanced proliferation and dopaminergic differentiation of ventral mesencephalic precursor cells by synergistic effect of FGF2 and reduced oxygen tension

    SciTech Connect

    Jensen, Pia; Gramsbergen, Jan-Bert; Zimmer, Jens; Widmer, Hans R.; Meyer, Morten

    2011-07-15

    Effective numerical expansion of dopaminergic precursors might overcome the limited availability of transplantable cells in replacement strategies for Parkinson's disease. Here we investigated the effect of fibroblast growth factor-2 (FGF2) and FGF8 on expansion and dopaminergic differentiation of rat embryonic ventral mesencephalic neuroblasts cultured at high (20%) and low (3%) oxygen tension. More cells incorporated bromodeoxyuridine in cultures expanded at low as compared to high oxygen tension, and after 6 days of differentiation there were significantly more neuronal cells in low than in high oxygen cultures. Low oxygen during FGF2-mediated expansion resulted also in a significant increase in tyrosine hydroxylase-immunoreactive (TH-ir) dopaminergic neurons as compared to high oxygen tension, but no corresponding effect was observed for dopamine release into the culture medium. However, switching FGF2-expanded cultures from low to high oxygen tension during the last two days of differentiation significantly enhanced dopamine release and intracellular dopamine levels as compared to all other treatment groups. In addition, the short-term exposure to high oxygen enhanced in situ assessed TH enzyme activity, which may explain the elevated dopamine levels. Our findings demonstrate that modulation of oxygen tension is a recognizable factor for in vitro expansion and dopaminergic differentiation of rat embryonic midbrain precursor cells.

  10. HSPB1 Enhances SIRT2-Mediated G6PD Activation and Promotes Glioma Cell Proliferation

    PubMed Central

    Cao, Fei; Chen, Mantao; Zheng, Xiujue; Zhan, Renya

    2016-01-01

    Heat shock proteins belong to a conserved protein family and are involved in multiple cellular processes. Heat shock protein 27 (Hsp27), also known as heat HSPB1, participates in cellular responses to not only heat shock, but also oxidative or chemical stresses. However, the contribution of HSPB1 to anti-oxidative response remains unclear. Here, we show that HSPB1 activates G6PD in response to oxidative stress or DNA damage. HSPB1 enhances the binding between G6PD and SIRT2, leading to deacetylation and activation of G6PD. Besides, HSPB1 activates G6PD to sustain cellular NADPH and pentose production in glioma cells. High expression of HSPB1 correlates with poor survivalrate of glioma patients. Together, our study uncovers the molecular mechanism by which HSPB1 activates G6PD to protect cells from oxidative and DNA damage stress. PMID:27711253

  11. 9-Methyl-β-carboline-induced cognitive enhancement is associated with elevated hippocampal dopamine levels and dendritic and synaptic proliferation.

    PubMed

    Gruss, Michael; Appenroth, Dorothea; Flubacher, Armin; Enzensperger, Christoph; Bock, Jörg; Fleck, Christian; Gille, Gabriele; Braun, Katharina

    2012-06-01

    β-Carbolines (BCs) belong to the heterogenous family of carbolines, which have been found exogenously, that is, in various fruits, meats, tobacco smoke, alcohol and coffee, but also endogenously, that is, blood, brain and CSF. These exogenous and endogenous BCs and some of their metabolites can exert neurotoxic effects, however, an unexpected stimulatory effect of 9-methyl-β-carboline (9-me-BC) on dopaminergic neurons in primary mesencephalic cultures was recently discovered. The aim of the present study was to extend our knowledge on the stimulatory effects of 9-me-BC and to test the hypothesis that 9-me-BC may act as a cognitive enhancer. We found that 10 days (but not 5 days) of pharmacological treatment with 9-me-BC (i) improves spatial learning in the radial maze, (ii) elevates dopamine levels in the hippocampal formation, and (iii) results after 10 days of treatment in elongated, more complex dendritic trees and higher spine numbers on granule neurons in the dentate gyrus of 9-me-BC-treated rats. Our results demonstrate that beyond its neuroprotective/neurorestorative and anti-inflammatory effects, 9-me-BC acts as a cognitive enhancer in a hippocampus-dependent task, and that the behavioral effects may be associated with a stimulatory impact on hippocampal dopamine levels and dendritic and synaptic proliferation.

  12. TC1(C8orf4) is upregulated by IL-1beta/TNF-alpha and enhances proliferation of human follicular dendritic cells.

    PubMed

    Kim, Youngmi; Kim, Jungtae; Park, Juhee; Bang, Seunghyun; Jung, Yusun; Choe, Jongseon; Song, Kyuyoung; Lee, Inchul

    2006-06-12

    Follicular dendritic cells (FDC) play crucial roles in immune regulation. TNF-alpha has been shown to be essential to the FDC network. However, the molecular regulation of FDC proliferation has not been characterized. Here, we show that TC1(C8orf4), a novel positive regulator of the Wnt/beta-catenin pathway in vertebrates, is upregulated by IL-1beta and TNF-alpha in the human FDC-like line HK. TC1 enhances HK cell proliferation, while TC1-knockdown inhibits the proliferation induced by IL-1beta, suggesting a role of TC1 as a regulator of FDC proliferation. The regulation by pro-inflammatory cytokines suggests that TC1 might be implicated in linking local inflammation to immune response by stimulating FDC.

  13. Protein-kinase-Cmu expression correlates with enhanced keratinocyte proliferation in normal and neoplastic mouse epidermis and in cell culture.

    PubMed

    Rennecke, J; Rehberger, P A; Fürstenberger, G; Johannes, F J; Stöhr, M; Marks, F; Richter, K H

    1999-01-05

    In order to gain insight into the biological function of a PKC iso-enzyme, the protein kinase Cmu, we analyzed the expression pattern of this protein in mouse epidermis and keratinocytes in culture. Daily analysis of neonatal mouse epidermis immediately after birth showed a time-dependent reduction in the PKCmu content. Expression of the proliferating-cell nuclear antigen (PCNA), indicative of the proliferative state of cells, was reduced synchronously with PKCmu as the hyperplastic state of the neonatal tissue declined. In epidermal mouse keratinocytes, fractionated according to their maturation state, PKCmu expression was restricted to PCNA-positive basal-cell fractions. In primary cultures of those cells, growth arrest and induction of terminal differentiation by Ca2+ resulted in strongly reduced PKCmu expression, concomitantly with the loss of PCNA expression. Treatment of PMK-R1 keratinocytes with 100 nM of the mitogen 12-O-tetradecanoylphorbol-13-acetate (TPA) resulted in activation of PKCmu, reflected by translocation from the cytosolic to the particulate fraction and by shifts in electrophoretic mobility. DNA synthesis was significantly inhibited by the PKCmu inhibitor Goedecke 6976, while Goedecke 6983 did not inhibit PKCmu. Carcinomas generated according to the 2-stage carcinogenesis protocol in mouse skin consistently exhibited high levels of PKCmu. These data correlate PKCmu expression with the proliferative state of murine keratinocytes and point to a role of PKCmu in growth stimulation. A correlation between PKCmu expression and enhanced cell proliferation was also observed for NIH3T3 fibroblasts transfected with and overexpressing human PKCmu.

  14. Thrombospondin-1 regulates adiposity and metabolic dysfunction in diet-induced obesity enhancing adipose inflammation and stimulating adipocyte proliferation

    PubMed Central

    Kong, Ping; Gonzalez-Quesada, Carlos; Li, Na; Cavalera, Michele; Lee, Dong-Wook

    2013-01-01

    As a typical matricellular protein, thrombospondin (TSP)-1, binds to the structural matrix and regulates cellular behavior by modulating growth factor and cytokine signaling. Obesity and diabetes are associated with marked upregulation of TSP-1 in adipose tissue. We hypothesized that endogenous TSP-1 may play an important role in the pathogenesis of diet-induced obesity and metabolic dysfunction. Accordingly, we examined the effects of TSP-1 gene disruption on weight gain, adiposity, and adipose tissue inflammation in mice receiving a high-fat diet (HFD: 60% fat, 20% carbohydrate) or a high-carbohydrate low-fat diet (HCLFD: 10% fat, 70% carbohydrate). HFD mice had significantly higher TSP-1 expression in perigonadal adipose tissue; TSP-1 was predominantly localized in the adipose interstitium. TSP-1 loss attenuated weight gain and fat accumulation in HFD and HCLFD groups. Compared with corresponding wild-type animals, TSP-1-null mice had decreased insulin levels but exhibited elevated free fatty acid and triglyceride levels, suggesting impaired fatty acid uptake. TSP-1 loss did not affect adipocyte size and had no effect on adipose vascular density. However, TSP-1-null mice exhibited attenuated tumor necrosis factor-α mRNA expression and reduced macrophage infiltration, suggesting a role for TSP-1 in mediating obesity-associated inflammation. In vitro, TSP-1 enhanced proliferation of 3T3-L1 preadipocytes but did not modulate inflammatory cytokine and chemokine synthesis. In conclusion, TSP-1 upregulation contributes to weight gain, adipose growth, and the pathogenesis of metabolic dysfunction. The effects of TSP-1 may involve stimulation of adipocyte proliferation, activation of inflammatory signaling, and facilitated fatty acid uptake by adipocytes. PMID:23757408

  15. Biomineral/Agarose Composite Gels Enhance Proliferation of Mesenchymal Stem Cells with Osteogenic Capability

    PubMed Central

    Suzawa, Yoshika; Kubo, Norihiko; Iwai, Soichi; Yura, Yoshiaki; Ohgushi, Hajime; Akashi, Mitsuru

    2015-01-01

    Hydroxyapatite (HA) or calcium carbonate (CaCO3) formed on an organic polymer of agarose gel is a biomaterial that can be used for bone tissue regeneration. However, in critical bone defects, the regeneration capability of these materials is limited. Mesenchymal stem cells (MSCs) are multipotent cells that can differentiate into bone forming osteoblasts. In this study, we loaded MSCs on HA- or CaCO3-formed agarose gel and cultured them with dexamethasone, which triggers the osteogenic differentiation of MSCs. High alkaline phosphatase activity was detected on both the HA- and CaCO3-formed agarose gels; however, basal activity was only detected on bare agarose gel. Bone-specific osteocalcin content was detected on CaCO3-formed agarose gel on Day 14 of culture, and levels subsequently increased over time. Similar osteocalcin content was detected on HA-formed agarose on Day 21 and levels increased on Day 28. In contrast, only small amounts of osteocalcin were found on bare agarose gel. Consequently, osteogenic capability of MSCs was enhanced on CaCO3-formed agarose at an early stage, and both HA- and CaCO3-formed agarose gels well supported the capability at a later stage. Therefore, MSCs loaded on either HA- or CaCO3-formed agarose could potentially be employed for the repair of critical bone defects. PMID:26110392

  16. Biomineral/Agarose Composite Gels Enhance Proliferation of Mesenchymal Stem Cells with Osteogenic Capability.

    PubMed

    Suzawa, Yoshika; Kubo, Norihiko; Iwai, Soichi; Yura, Yoshiaki; Ohgushi, Hajime; Akashi, Mitsuru

    2015-06-23

    Hydroxyapatite (HA) or calcium carbonate (CaCO3) formed on an organic polymer of agarose gel is a biomaterial that can be used for bone tissue regeneration. However, in critical bone defects, the regeneration capability of these materials is limited. Mesenchymal stem cells (MSCs) are multipotent cells that can differentiate into bone forming osteoblasts. In this study, we loaded MSCs on HA- or CaCO3-formed agarose gel and cultured them with dexamethasone, which triggers the osteogenic differentiation of MSCs. High alkaline phosphatase activity was detected on both the HA- and CaCO3-formed agarose gels; however, basal activity was only detected on bare agarose gel. Bone-specific osteocalcin content was detected on CaCO3-formed agarose gel on Day 14 of culture, and levels subsequently increased over time. Similar osteocalcin content was detected on HA-formed agarose on Day 21 and levels increased on Day 28. In contrast, only small amounts of osteocalcin were found on bare agarose gel. Consequently, osteogenic capability of MSCs was enhanced on CaCO3-formed agarose at an early stage, and both HA- and CaCO3-formed agarose gels well supported the capability at a later stage. Therefore, MSCs loaded on either HA- or CaCO3-formed agarose could potentially be employed for the repair of critical bone defects.

  17. Enhanced alveolar monocytic phagocyte (macrophage) proliferation in tobacco and marijuana smokers

    SciTech Connect

    Barbers, R.G.; Evans, M.J.; Gong, H. Jr.; Tashkin, D.P. )

    1991-05-01

    We tested the hypothesis that enhanced cell division accounted for the augmented numbers of monocytic phagocytes with characteristics attributed to alveolar macrophages (AM) found in the lungs of habitual tobacco (T) and marijuana (M) smokers. The monocytic phagocytes, that is, alveolar macrophages, were obtained by bronchoalveolar lavage (BAL) from 12 nonsmoking subjects; 10 subjects who smoked T only (TS); 13 subjects who smoked M only (MS); and 6 smokers of both T and M (MTS). The replication of these cells was determined by measuring the incorporation of ({sup 3}H)thymidine into the DNA of dividing cells and visually counting 2,000 cells on autoradiographically prepared cytocentrifuge cell preparations. This study demonstrated that the number of ({sup 3}H)thymidine-labeled monocytic phagocytes with characteristics of alveolar macrophages from either TS or MS have a higher proliferative index compared to cells (macrophages) from nonsmokers, p less than 0.05 by one-way ANOVA. The total number of BAL macrophages that are in mitosis in TS (17.90 +/- 4.50 labeled AM x 10(3)/ml) or MTS (10.50 +/- 4.20 labeled AM x 10(3)/ml) are 18- and 10-fold greater, respectively, than the number obtained from nonsmokers (1.01 +/- 0.18 labeled AM x 10(3)/ml). Interestingly, the number of ({sup 3}H)thymidine-labeled macrophages from MS (2.90 +/- 0.66 labeled AM x 10(3)/ml) are also greater than the number obtained from nonsmokers, although this is not statistically significant. The stimulus augmenting alveolar macrophage replication is as yet unknown but may likely be found in the T or M smoke.

  18. Gelatin Directly Enhances Neurogenic Differentiation Potential in Bone Marrow-Derived Mesenchymal Stem Cells Without Stimulation of Neural Progenitor Cell Proliferation.

    PubMed

    Lee, Hyun; Han, Na Rae; Hwang, Jae Yeon; Yun, Jung Im; Kim, Choonghyo; Park, Kyu Hyun; Lee, Seung Tae

    2016-09-01

    Gelatin has been reported to induce generation of mesenchymal stem cells (MSCs) with enhanced potential of differentiation into neuronal lineage cells. However, the presence of various cell types besides MSCs in bone marrow has raised doubts about the effects of gelatin. In the following report, we determined whether gelatin can directly enhance neurogenic differentiation potential in MSCs without proliferation of neural progenitor cells (NPCs). MSCs comprised a high proportion of bone marrow-derived primary cells (BMPCs) and gelatin induced significant increases in MSC proliferation during primary culture, and the proportion of MSCs was maintained at more than 99% throughout the subculture. However, NPCs comprised a low percentage of BMPCs and a decrease in proliferation was detected despite gelatin treatment during the primary culture, and the proportion of subcultured NPCs gradually decreased. In a similar manner, MSCs exposed to gelatin during primary culture showed more enhanced neurogenic differentiation ability than those not exposed to gelatin. Together, these results demonstrate that gelatin directly enhances neurogenic differentiation in bone marrow-derived MSCs without stimulating NPC proliferation.

  19. Assignment of human myocyte-specific enhancer binding factor 2C (hMEF2C) to human chromosome 5q14 and evidence that MEF2C is evolutionarily conserved

    SciTech Connect

    Krainc, D.; Lipton, S.A.; Haas, M.; Ward, D.C.

    1995-10-10

    Human myocyte-specific enhancer binding factor 2C (hMEF2C) belongs to the MEF2 subfamily of the MADS (MCM1, AGAMOUS, DEF A, serum response factor) family of transcription factors. Members of the MADS family share a conserved domain - the MADS domain - that is necessary for DNA binding. Highly conserved versions of the MADS domain and of an adjacent domain that is known as the MEF2 domain are found in members of the MEF2 subfamily. Both of these domains are necessary for binding to the MEF2 regulatory element. This regulatory element is known to be functionally important in a variety of muscle-specific genes and possibly in the brain creatine kinase gene. The MEF2C gene product activates transcription by binding to the MEF2 element. hMEF2C is expressed at high levels in postmitotic neurons in the brain, where it is most abundant in the cerebral cortex, and is also expressed in differentiated myotubes. Several lines of evidence suggest the existence of a rat homologue of MEF2C, and a mouse homologue has been cloned. The mouse gene was mapped to mouse chromosome 13 in a region that is syntenic to human 5q13-q15. 12 refs., 1 fig.

  20. Perturbation of transcription factor Nur77 expression mediated by myocyte enhancer factor 2D (MEF2D) regulates dopaminergic neuron loss in response to 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP).

    PubMed

    Mount, Matthew P; Zhang, Yi; Amini, Mandana; Callaghan, Steve; Kulczycki, Jerzy; Mao, Zixu; Slack, Ruth S; Anisman, Hymie; Park, David S

    2013-05-17

    We have earlier reported the critical nature of calpain-CDK5-MEF2 signaling in governing dopaminergic neuronal loss in vivo. CDK5 mediates phosphorylation of the neuronal survival factor myocyte enhancer factor 2 (MEF2) leading to its inactivation and loss. However, the downstream factors that mediate MEF2-regulated survival are unknown. Presently, we define Nur77 as one such critical downstream survival effector. Following 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) treatment in vivo, Nur77 expression in the nigrostriatal region is dramatically reduced. This loss is attenuated by expression of MEF2. Importantly, MEF2 constitutively binds to the Nur77 promoter in neurons under basal conditions. This binding is lost following 1-methyl-4-phenylpyridinium treatment. Nur77 deficiency results in significant sensitization to dopaminergic loss following 1-methyl-4-phenylpyridinium/MPTP treatment, in vitro and in vivo. Furthermore, Nur77-deficient MPTP-treated mice displayed significantly reduced levels of dopamine and 3,4-Dihydroxyphenylacetic acid in the striatum as well as elevated post synaptic FosB activity, indicative of increased nigrostriatal damage when compared with WT MPTP-treated controls. Importantly, this sensitization in Nur77-deficient mice was rescued with ectopic Nur77 expression in the nigrostriatal system. These results indicate that the inactivation of Nur77, induced by loss of MEF2 activity, plays a critical role in nigrostriatal degeneration in vivo.

  1. Aged garlic extract enhances heme oxygenase-1 and glutamate-cysteine ligase modifier subunit expression via the nuclear factor erythroid 2-related factor 2-antioxidant response element signaling pathway in human endothelial cells.

    PubMed

    Hiramatsu, Kei; Tsuneyoshi, Tadamitsu; Ogawa, Takahiro; Morihara, Naoaki

    2016-02-01

    The nuclear factor erythroid 2-related factor 2 (Nrf2)-antioxidant response element (ARE) pathway defends cells against oxidative stress and regulates the cellular redox balance. Activation of this pathway induces a variety of antioxidant enzymes, resulting in the protection of our bodies against oxidative damage. It has been reported that aged garlic extract (AGE), a garlic preparation that is rich in water-soluble cysteinyl moieties, reduces oxidative stress and helps to ameliorate of cardiovascular, renal and hepatic diseases. We hypothesized that AGE enhances the expression of antioxidant enzymes via the Nrf2-ARE pathway in human umbilical vein endothelial cells in culture. Gene expression of antioxidant enzymes was measured using real-time polymerase chain reaction. Nuclear accumulation of Nrf2 and antioxidant enzymes expression were evaluated using western blotting analyses. We found that AGE promoted the accumulation of Nrf2 into the nucleus in a time- and dose-dependent manner and increased the gene expression and polypeptide level of heme oxygenase-1 (HO-1) and glutamate-cysteine ligase modifier subunit (GCLM). Moreover, the effect of AGE in elevating the gene expression of HO-1 and GCLM was found to be mediated via Nrf2 activation in human umbilical vein endothelial cells. Taken together, these observations suggest that AGE induces the expression of HO-1 and GCLM, which are antioxidant enzymes, via activation of the Nrf2-ARE signaling pathway.

  2. Delayed remote ischemic preconditioning produces an additive cardioprotection to sevoflurane postconditioning through an enhanced heme oxygenase 1 level partly via nuclear factor erythroid 2-related factor 2 nuclear translocation.

    PubMed

    Zhou, Chenghui; Li, Huatong; Yao, Yuntai; Li, Lihuan

    2014-11-01

    Although both sevoflurane postconditioning (SPoC) and delayed remote ischemic preconditioning (DRIPC) have been proved effective in various animal and human studies, the combined effect of these 2 strategies remains unclear. Therefore, this study was designed to investigate this effect and elucidate the related signal mechanisms in a Langendorff perfused rat heart model. After 30-minute balanced perfusion, isolated hearts were subjected to 30-minute ischemia followed by 60-minute reperfusion except 90-minute perfusion for control. A synergic cardioprotective effect of SPoC (3% v/v) and DRIPC (4 cycles 5-minute occlusion/5-minute reflow at the unilateral hindlimb once per day for 3 days before heart isolation) was observed with facilitated cardiac functional recovery and decreased cardiac enzyme release. The infarct size-limiting effect was more pronounced in the combined group (6.76% ± 2.18%) than in the SPoC group (16.50% ± 4.55%, P < .001) or in the DRIPC group (10.22% ± 2.57%, P = .047). Subsequent analysis revealed that an enhanced heme oxygenase 1 (HO-1) expression, but not protein kinase B/AKt or extracellular signal-regulated kinase 1 and 2 activation, was involved in the synergic cardioprotective effect, which was further confirmed in the messenger RNA level of HO-1. Such trend was also observed in the nuclear factor erythroid 2-related factor 2 (Nrf2) nuclear translocation, an upstream regulation of HO-1. In addition, correlation analysis showed a significantly positive relationship between HO-1 expression and Nrf2 translocation (r = 0.729, P < .001). Hence, we conclude that DRIPC may produce an additive cardioprotection to SPoC through an enhanced HO-1 expression partly via Nrf2 translocation.

  3. Knockdown of eIF4E suppresses cell proliferation, invasion and enhances cisplatin cytotoxicity in human ovarian cancer cells.

    PubMed

    Wan, Jing; Shi, Fang; Xu, Zhanzhan; Zhao, Min

    2015-12-01

    Eukaryotic initiation factor 4E (eIF4E) plays an important role in cap-dependent translation. The overexpression of eIF4E gene has been found in a variety of human malignancies. In this study, we attempted to identify the potential effects of eIF4E and explore the possibility of eIF4E as a therapeutic target for the treatment of human ovarian cancer. First the activation of eIF4E protein was detected with m7-GTP cap binding assays in ovarian cancer and control cells. Next, the eIF4E-shRNA expression plasmids were used to specifically inhibit eIF4E activity in ovarian cancer cells line A2780 and C200. The effects of knockdown eIF4E gene on cell proliferation, migration and invasion were investigated in vitro. Moreover, the changes of cell cycle and apoptosis of ovarian cancer cells were detected by flow cytometry. Finally, we investigated the effect of knockdown of eIF4E on the chemosensitivity of ovarian cancer cells to cisplatin in vitro. Our results show there is elevated activation of eIF4E in ovarian cancer cells compared with normal human ovarian epithelial cell line. The results of BrdU incorporation and FCM assay indicate that knockdown of eIF4E efficiently suppressed cell growth and induce cell cycle arrest in G1 phase and subsequent apoptosis in ovarian cancer cells. From Transwell assay analysis, knockdown eIF4E significantly decrease cellular migration and invasion of ovarian cancer cells. We also confirmed that knockdown eIF4E could synergistically enhance the cytotoxicity effects of cisplatin to cancer cells and sensitized cisplatin-resistant C200 cells in vitro. This study demonstrates that the activation of eIF4E gene is an essential component of the malignant phenotype in ovarian cancer, and aberration of eIF4E expression is associated with proliferation, migration, invasion and chemosensitivity to cisplatin in ovarian cancer cells. Knockdown eIF4E gene can be used as a potential therapeutic target for the treatment of human ovarian cancer.

  4. Distinct Effects of miR-210 Reduction on Neurogenesis: Increased Neuronal Survival of Inflammation But Reduced Proliferation Associated with Mitochondrial Enhancement.

    PubMed

    Voloboueva, Ludmila A; Sun, Xiaoyun; Xu, Lijun; Ouyang, Yi-Bing; Giffard, Rona G

    2017-03-15

    Neurogenesis is essential to brain development and plays a central role in the response to brain injury. Stroke and head trauma stimulate proliferation of endogenous neural stem cells (NSCs); however, the survival of young neurons is sharply reduced by postinjury inflammation. Cellular mitochondria are critical to successful neurogenesis and are a major target of inflammatory injury. Mitochondrial protection was shown to improve survival of young neurons. This study tested whether reducing cellular microRNA-210 (miR-210) would enhance mitochondrial function and improve survival of young murine neurons under inflammatory conditions. Several studies have demonstrated the potential of miR-210 inhibition to enhance and protect mitochondrial function through upregulation of mitochondrial proteins. Here, miR-210 inhibition significantly increased neuronal survival and protected the activity of mitochondrial enzymes cytochrome c oxidase and aconitase in differentiating NSC cultures exposed to inflammatory mediators. Unexpectedly, we found that reducing miR-210 significantly attenuated NSC proliferation upon induction of differentiation. Further investigation revealed that increased mitochondrial function suppressed the shift to primarily glycolytic metabolism and reduced mitochondrial length characteristic of dividing cells. Activation of AMP-regulated protein kinase-retinoblastoma signaling is important in NSC proliferation and the reduction of this activation observed by miR-210 inhibition is one mechanism contributing to the reduced proliferation. Postinjury neurogenesis occurs as a burst of proliferation that peaks in days, followed by migration and differentiation over weeks. Our studies suggest that mitochondrial protective miR-210 inhibition should be delayed until after the initial burst of proliferation, but could be beneficial during the prolonged differentiation stage.SIGNIFICANCE STATEMENT Increasing the success of endogenous neurogenesis after brain injury

  5. Conditional deletion of cardiomyocyte peroxisome proliferator-activated receptor γ enhances myocardial ischemia-reperfusion injury in mice.

    PubMed

    Hobson, Michael J; Hake, Paul W; O'Connor, Michael; Schulte, Christine; Moore, Victoria; James, Jeanne M; Piraino, Giovanna; Zingarelli, Basilia

    2014-01-01

    The nuclear transcription factor peroxisome proliferator-activated receptor γ (PPARγ) is a key regulator of the inflammatory response to an array of biologic insults. We have previously demonstrated that PPARγ ligands reduce myocardial ischemia-reperfusion injury in rodents. In the current study, we directly determined the role of cardiomyocyte PPARγ in ischemia-reperfusion injury, using a model of conditional cardiomyocyte-specific deletion of PPARγ in vivo. In mice, α-myosin heavy chain-restricted Cre-mediated PPARγ deficiency was induced by tamoxifen treatment (30 mg/kg intraperitoneally) for 4 days (PPARγ mice), whereas controls included mice treated with the oil diluent vehicle (PPARγ mice). Western blot and histochemical analyses confirmed that expression of PPARγ protein was abolished in cardiomyocytes of mice treated with tamoxifen, but not with vehicle. After tamoxifen or vehicle treatment, animals were subjected to 30-min ligation of the left anterior descending coronary artery followed by 2-h reperfusion. In PPARγ mice, myocardial ischemia and reperfusion induced extensive myocardial damage, which was associated with elevated tissue activity of myeloperoxidase, indicating infiltration of neutrophils, and elevated plasma levels of troponin I when compared with PPARγ mice. Upon echocardiographic analysis, PPARγ mice also demonstrated ventricular dilatation and systolic dysfunction. Plasma levels of the proinflammatory cytokines interleukin 1β and interleukin 6 were higher in PPARγ mice when compared with PPARγ mice. These pathological events in PPARγ mice were associated with enhanced nuclear factor κB DNA binding in the infarcted hearts. Thus, our data suggest that cardiomyocyte PPARγ is a crucial protective receptor and may prevent reperfusion injury by modulating mechanisms of inflammation.

  6. Body protective compound-157 enhances alkali-burn wound healing in vivo and promotes proliferation, migration, and angiogenesis in vitro.

    PubMed

    Huang, Tonglie; Zhang, Kuo; Sun, Lijuan; Xue, Xiaochang; Zhang, Cun; Shu, Zhen; Mu, Nan; Gu, Jintao; Zhang, Wangqian; Wang, Yukun; Zhang, Yingqi; Zhang, Wei

    2015-01-01

    Chemical burns take up a high proportion of burns admissions and can penetrate deep into tissues. Various reagents have been applied in the treatment of skin chemical burns; however, no optimal reagent for skin chemical burns currently exists. The present study investigated the effect of topical body protective compound (BPC)-157 treatment on skin wound healing, using an alkali burn rat model. Topical treatment with BPC-157 was shown to accelerate wound closure following an alkali burn. Histological examination of skin sections with hematoxylin-eosin and Masson staining showed better granulation tissue formation, reepithelialization, dermal remodeling, and a higher extent of collagen deposition when compared to the model control group on the 18th day postwounding. BPC-157 could promote vascular endothelial growth factor expression in wounded skin tissues. Furthermore, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and cell cycle analysis demonstrated that BPC-157 enhanced the proliferation of human umbilical vein endothelial cells (HUVECs). Transwell assay and wound healing assay showed that BPC-157 significantly promoted migration of HUVECs. We also observed that BPC-157 upregulated the expression of VEGF-a and accelerated vascular tube formation in vitro. Moreover, further studies suggested that BPC-157 regulated the phosphorylation level of extracellular signal-regulated kinases 1 and 2 (ERK1/2) as well as its downstream targets, including c-Fos, c-Jun, and Egr-1, which are key molecules involved in cell growth, migration, and angiogenesis. Altogether, our results indicated that BPC-157 treatment may accelerate wound healing in a model of alkali burn-induced skin injury. The therapeutic mechanism may be associated with accelerated granulation tissue formation, reepithelialization, dermal remodeling, and collagen deposition through ERK1/2 signaling pathway.

  7. Body protective compound-157 enhances alkali-burn wound healing in vivo and promotes proliferation, migration, and angiogenesis in vitro

    PubMed Central

    Huang, Tonglie; Zhang, Kuo; Sun, Lijuan; Xue, Xiaochang; Zhang, Cun; Shu, Zhen; Mu, Nan; Gu, Jintao; Zhang, Wangqian; Wang, Yukun; Zhang, Yingqi; Zhang, Wei

    2015-01-01

    Chemical burns take up a high proportion of burns admissions and can penetrate deep into tissues. Various reagents have been applied in the treatment of skin chemical burns; however, no optimal reagent for skin chemical burns currently exists. The present study investigated the effect of topical body protective compound (BPC)-157 treatment on skin wound healing, using an alkali burn rat model. Topical treatment with BPC-157 was shown to accelerate wound closure following an alkali burn. Histological examination of skin sections with hematoxylin–eosin and Masson staining showed better granulation tissue formation, reepithelialization, dermal remodeling, and a higher extent of collagen deposition when compared to the model control group on the 18th day postwounding. BPC-157 could promote vascular endothelial growth factor expression in wounded skin tissues. Furthermore, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and cell cycle analysis demonstrated that BPC-157 enhanced the proliferation of human umbilical vein endothelial cells (HUVECs). Transwell assay and wound healing assay showed that BPC-157 significantly promoted migration of HUVECs. We also observed that BPC-157 upregulated the expression of VEGF-a and accelerated vascular tube formation in vitro. Moreover, further studies suggested that BPC-157 regulated the phosphorylation level of extracellular signal-regulated kinases 1 and 2 (ERK1/2) as well as its downstream targets, including c-Fos, c-Jun, and Egr-1, which are key molecules involved in cell growth, migration, and angiogenesis. Altogether, our results indicated that BPC-157 treatment may accelerate wound healing in a model of alkali burn-induced skin injury. The therapeutic mechanism may be associated with accelerated granulation tissue formation, reepithelialization, dermal remodeling, and collagen deposition through ERK1/2 signaling pathway. PMID:25995620

  8. Postnatal Treadmill Exercise Alleviates Prenatal Stress-Induced Anxiety in Offspring Rats by Enhancing Cell Proliferation Through 5-Hydroxytryptamine 1A Receptor Activation

    PubMed Central

    2016-01-01

    Purpose: Stress during pregnancy is a risk factor for the development of anxiety-related disorders in offspring later in life. The effects of treadmill exercise on anxiety-like behaviors and hippocampal cell proliferation were investigated using rats exposed to prenatal stress. Methods: Exposure of pregnant rats to a hunting dog in an enclosed room was used to induce stress. Anxiety-like behaviors of offspring were evaluated using the elevated plus maze test. Immunohistochemistry for the detection of 5-bromo-2ʹ- deoxyuridine and doublecortin (DCX) in the hippocampal dentate gyrus and 5-hydroxytryptamine 1A receptors (5-HT1A) in the dorsal raphe was conducted. Brain-derived neurotrophic factor (BDNF) and tyrosine kinase B (TrkB) levels in the hippocampus were evaluated by western blot analysis. Results: Offspring of maternal rats exposed to stress during pregnancy showed anxiety-like behaviors. Offspring also showed reduced expression of BDNF, TrkB, and DCX in the dentate gyrus, decreased cell proliferation in the hippocampus, and reduced 5-HT1A expression in the dorsal raphe. Postnatal treadmill exercise by offspring, but not maternal exercise during pregnancy, enhanced cell proliferation and expression of these proteins. Conclusions: Postnatal treadmill exercise ameliorated anxiety-like behaviors in offspring of stressed pregnant rats, and the alleviating effect of exercise on these behaviors is hypothesized to result from enhancement of cell proliferation through 5-HT1A activation in offspring rats. PMID:27230461

  9. Activation of nuclear factor erythroid 2-related factor 2 coordinates dimethylarginine dimethylaminohydrolase/PPAR-γ/endothelial nitric oxide synthase pathways that enhance nitric oxide generation in human glomerular endothelial cells.

    PubMed

    Luo, Zaiming; Aslam, Shakil; Welch, William J; Wilcox, Christopher S

    2015-04-01

    Dimethylarginine dimethylaminohydrolase (DDAH) degrades asymmetric dimethylarginine, which inhibits nitric oxide (NO) synthase (NOS). Nuclear factor erythroid 2-related factor 2 (Nrf2) is a transcriptional factor that binds to antioxidant response elements and transcribes many antioxidant genes. Because the promoters of the human DDAH-1 and DDAH-2, endothelial NOS (eNOS) and PPAR-γ genes contain 2 to 3 putative antioxidant response elements, we hypothesized that they were regulated by Nrf2/antioxidant response element. Incubation of human renal glomerular endothelial cells with the Nrf2 activator tert-butylhydroquinone (20 μmol·L(-1)) significantly (P<0.05) increased NO and activities of NOS and DDAH and decreased asymmetric dimethylarginine. It upregulated genes for hemoxygenase-1, eNOS, DDAH-1, DDAH-2, and PPAR-γ and partitioned Nrf2 into the nucleus. Knockdown of Nrf2 abolished these effects. Nrf2 bound to one antioxidant response element on DDAH-1 and DDAH-2 and PPAR-γ promoters but not to the eNOS promoter. An increased eNOS and phosphorylated eNOS (P-eNOSser-1177) expression with tert-butylhydroquinone was prevented by knockdown of PPAR-γ. Expression of Nrf2 was reduced by knockdown of PPAR-γ, whereas PPAR-γ was reduced by knockdown of Nrf2, thereby demonstrating 2-way positive interactions. Thus, Nrf2 transcribes HO-1 and other genes to reduce reactive oxygen species, and DDAH-1 and DDAH-2 to reduce asymmetric dimethylarginine and PPAR-γ to increase eNOS and its phosphorylation and activity thereby coordinating 3 pathways that enhance endothelial NO generation.

  10. CYP2S1 depletion enhances colorectal cell proliferation is associated with PGE2-mediated activation of β-catenin signaling

    SciTech Connect

    Yang, Chao; Li, Changyuan; Li, Minle; Tong, Xuemei; Hu, Xiaowen; Yang, Xuhan; Yan, Xiaomei; He, Lin; Wan, Chunling

    2015-02-15

    Colorectal epithelial cancer is one of the most common cancers in the world and its 5-year survival rate is still relatively low. Cytochrome P450 (CYP) enzymes in epithelial cells lining the alimentary tract play an important role in the oxidative metabolism of a wide range of xenobiotics, including (pro-)carcinogens and endogenous compounds. Although CYP2S1, a member of CYP family, strongly expressed in many extrahepatic tissues, the role of CYP2S1 in cancer remains unclear. To investigate whether CYP2S1 involves in colorectal carcinogenesis, cell proliferation was analyzed in HCT116 cells depleted of CYP2S1 using small hairpin interfering RNA. Our data show that CYP2S1 knockdown promotes cell proliferation through increasing the level of endogenous prostaglandin E2(PGE2). PGE2, in turn, reduces phosphorylation of β-catenin and activates β-catenin signaling, which contributes to the cell proliferation. Furthermore, CYP2S1 knockdown increase tumor growth in xenograft mouse model. In brief, these results demonstrate that CYP2S1 regulates colorectal cancer growth through associated with PGE2-mediated activation of β-catenin signaling. - Highlights: • Knockdown of CYP2S1 expression improve HCT116 cell proliferation in vitro and in vivo. • Elevate PGE2 production in CYP2S1 knockdown cell is associated with its proliferation. • Elevate PGE2 level in CYP2S1 knockdown cells enhance β-catenin accumulation. • β-catenin activate TCF/LEF and target gene expression thus promote cell proliferation.

  11. Vaccination with cell immunoglobulin mucin-1 antibodies and inactivated influenza enhances vaccine-specific lymphocyte proliferation, interferon-γ production and cross-strain reactivity

    PubMed Central

    Soo Hoo, W; Jensen, E R; Saadat, A; Nieto, D; Moss, R B; Carlo, D J; Moll, T

    2006-01-01

    Influenza virus causes a contagious and potentially serious infection of the upper respiratory tract. While neutralizing antibodies are protective against infection, the problem of antigenic drift remains, requiring the constant monitoring and development of new vaccines. The magnitude of this situation is underscored by the emergence of new potentially human pathogenic influenza strains, avian H5N1 being the most recent example. We present evidence that antibodies against T cell immunoglobulin mucin-1 (TIM-1), a recently identified immunomodulatory molecule, stimulate cellular immunity against influenza viruses and cross-strain immune reactivity. To determine potential immunostimulatory properties of anti-TIM-1, mice were vaccinated with inactivated influenza virus in the presence or absence of TIM-1-specific monoclonal antibodies. Development of cellular immunity against both the influenza strain used for immunization and serotypically distinct virus strains was monitored 3 weeks after vaccination by determining antigen-specific lymphocyte proliferation and cytokine production. Results show that TIM-1 antibodies enhance antigen-specific cellular proliferation (P < 0·05) and interferon (IFN)-γ production (P < 0·01). Using blocking anti-CD4 and CD8 antibodies, it was observed that antigen-specific cellular proliferation is CD4-dependent and that the majority of proliferating cells are CD4+. Finally, vaccination with inactivated influenza virus with TIM-1 antibody results in the significant (P < 0·001) induction of proliferation and IFN-γ production upon stimulation with one of three serologically distinct strains. TIM-1 antibodies demonstrate an adjuvant effect promoting antigen-specific cellular proliferation and IFN-γ production, which are important for the promotion of cell-mediated immunity. These results are the first to suggest that TIM-1 antibody may serve as a potent adjuvant in the development of new influenza virus vaccines. PMID:16792682

  12. Low-level Ga-Al-As laser irradiation enhances osteoblast proliferation through activation of Hedgehog signaling pathway

    NASA Astrophysics Data System (ADS)

    Li, Qiushi; Qu, Zhou; Chen, Yingxin; Liu, Shujie; Zhou, Yanmin

    2014-12-01

    Low-level laser irradiation has been reported to promote bone formation, but the molecular mechanism is still unclear. Hedgehog signaling pathway has been reported to play an important role in promoting bone formation. The aim of the present study was to examine whether low-level Ga-Al-As laser (808 nm) irradiation could have an effect on Hedgehog signaling pathway during osteoblast proliferation in vitro. Mouse osteoblastic cell line MC3T3-E1 was cultured in vitro. The cultures after laser irradiation (3.75J/cm2) were treated with recombinant N-terminals Sonic Hedgehog (N-Shh)or Hedgehog inhibitor cyclopamine (cy). The experiment was divided into 4 group, group 1:laser irradiation, group 2: laser irradiation and N-Shh, group 3: laser irradiation and cy, group 4:control with no laser irradiation. On day 1,2 and 3,cell proliferation was determined by cell counting, Cell Counting Kit-8.On 12 h and 24 h, cell cycle was detected by flow cytometry. Proliferation activity of laser irradiation and N-Shh group was remarkably increased compared with those of laser irradiation group. Proliferation activity of laser irradiation and cy group was remarkably decreased compared with those of laser irradiation group, however proliferation activity of laser irradiation and cy group was remarkably increased compared with those of control group. These results suggest that low-level Ga-Al-As laser irradiation activate Hedgehog signaling pathway during osteoblast proliferation in vitro. Hedgehog signaling pathway is one of the signaling pathways by which low-level Ga-Al-As laser irradiation regulates osteoblast proliferation.

  13. Enhanced expression of cyclins and cyclin-dependent kinases in aniline-induced cell proliferation in rat spleen.

    PubMed

    Wang, Jianling; Wang, Gangduo; Ma, Huaxian; Khan, M Firoze

    2011-01-15

    Aniline exposure is associated with toxicity to the spleen leading to splenomegaly, hyperplasia, fibrosis and a variety of sarcomas of the spleen on chronic exposure. In earlier studies, we have shown that aniline exposure leads to iron overload, oxidative stress and activation of redox-sensitive transcription factors, which could regulate various genes leading to a tumorigenic response in the spleen. However, molecular mechanisms leading to aniline-induced cellular proliferation in the spleen remain largely unknown. This study was, therefore, undertaken on the regulation of G1 phase cell cycle proteins (cyclins), expression of cyclin-dependent kinases (CDKs), phosphorylation of retinoblastoma protein (pRB) and cell proliferation in the spleen, in an experimental condition preceding a tumorigenic response. Male SD rats were treated with aniline (0.5 mmol/kg/day via drinking water) for 30 days (controls received drinking water only), and splenocyte proliferation, protein expression of G1 phase cyclins, CDKs and pRB were measured. Aniline treatment resulted in significant increases in splenocyte proliferation, based on cell counts, cell proliferation markers including proliferating cell nuclear antigen (PCNA), nuclear Ki67 protein (Ki67) and minichromosome maintenance (MCM), MTT assay and flow cytometric analysis. Western blot analysis of splenocyte proteins from aniline-treated rats showed significantly increased expression of cyclins D1, D2, D3 and E, as compared to the controls. Similarly, real-time PCR analysis showed significantly increased mRNA expression for cyclins D1, D2, D3 and E in the spleens of aniline-treated rats. The overexpression of these cyclins was associated with increases in the expression of CDK4, CDK6, CDK2 as well as phosphorylation of pRB protein. Our data suggest that increased expression of cyclins, CDKs and phosphorylation of pRB protein could be critical in cell proliferation, and may contribute to aniline-induced tumorigenic response in

  14. Enhanced expression of cyclins and cyclin-dependent kinases in aniline-induced cell proliferation in rat spleen

    SciTech Connect

    Wang Jianling; Wang Gangduo; Ma Huaxian; Khan, M. Firoze

    2011-01-15

    Aniline exposure is associated with toxicity to the spleen leading to splenomegaly, hyperplasia, fibrosis and a variety of sarcomas of the spleen on chronic exposure. In earlier studies, we have shown that aniline exposure leads to iron overload, oxidative stress and activation of redox-sensitive transcription factors, which could regulate various genes leading to a tumorigenic response in the spleen. However, molecular mechanisms leading to aniline-induced cellular proliferation in the spleen remain largely unknown. This study was, therefore, undertaken on the regulation of G1 phase cell cycle proteins (cyclins), expression of cyclin-dependent kinases (CDKs), phosphorylation of retinoblastoma protein (pRB) and cell proliferation in the spleen, in an experimental condition preceding a tumorigenic response. Male SD rats were treated with aniline (0.5 mmol/kg/day via drinking water) for 30 days (controls received drinking water only), and splenocyte proliferation, protein expression of G1 phase cyclins, CDKs and pRB were measured. Aniline treatment resulted in significant increases in splenocyte proliferation, based on cell counts, cell proliferation markers including proliferating cell nuclear antigen (PCNA), nuclear Ki67 protein (Ki67) and minichromosome maintenance (MCM), MTT assay and flow cytometric analysis. Western blot analysis of splenocyte proteins from aniline-treated rats showed significantly increased expression of cyclins D1, D2, D3 and E, as compared to the controls. Similarly, real-time PCR analysis showed significantly increased mRNA expression for cyclins D1, D2, D3 and E in the spleens of aniline-treated rats. The overexpression of these cyclins was associated with increases in the expression of CDK4, CDK6, CDK2 as well as phosphorylation of pRB protein. Our data suggest that increased expression of cyclins, CDKs and phosphorylation of pRB protein could be critical in cell proliferation, and may contribute to aniline-induced tumorigenic response in

  15. EPO-independent functional EPO receptor in breast cancer enhances estrogen receptor activity and promotes cell proliferation

    SciTech Connect

    Reinbothe, Susann; Larsson, Anna-Maria; Vaapil, Marica; Wigerup, Caroline; Sun, Jianmin; Jögi, Annika; Neumann, Drorit; Rönnstrand, Lars; Påhlman, Sven

    2014-02-28

    Highlights: • New anti-human EPOR antibody confirms full-length EPOR expression in breast cancer cells. • Proliferation of breast cancer cells is not affected by rhEPO treatment in vitro. • EPOR knockdown impairs proliferation of ERa positive breast cancer cells. • EPOR knockdown reduces AKT phosphorylation and ERa activity. - Abstract: The main function of Erythropoietin (EPO) and its receptor (EPOR) is the stimulation of erythropoiesis. Recombinant human EPO (rhEPO) is therefore used to treat anemia in cancer patients. However, clinical trials have indicated that rhEPO treatment might promote tumor progression and has a negative effect on patient survival. In addition, EPOR expression has been detected in several cancer forms. Using a newly produced anti-EPOR antibody that reliably detects the full-length isoform of the EPOR we show that breast cancer tissue and cells express the EPOR protein. rhEPO stimulation of cultured EPOR expressing breast cancer cells did not result in increased proliferation, overt activation of EPOR (receptor phosphorylation) or a consistent activation of canonical EPOR signaling pathway mediators such as JAK2, STAT3, STAT5, or AKT. However, EPOR knockdown experiments suggested functional EPO receptors in estrogen receptor positive (ERα{sup +}) breast cancer cells, as reduced EPOR expression resulted in decreased proliferation. This effect on proliferation was not seen in ERα negative cells. EPOR knockdown decreased ERα activity further supports a mechanism by which EPOR affects proliferation via ERα-mediated mechanisms. We show that EPOR protein is expressed in breast cancer cells, where it appears to promote proliferation by an EPO-independent mechanism in ERα expressing breast cancer cells.

  16. β-Hydroxy-β-methylbutyrate (HMB) enhances the proliferation of satellite cells in fast muscles of aged rats during recovery from disuse atrophy.

    PubMed

    Alway, Stephen E; Pereira, Suzette L; Edens, Neile K; Hao, Yanlei; Bennett, Brian T

    2013-09-01

    Loss of myonuclei by apoptosis is thought to contribute to sarcopenia. We have previously shown, that the leucine metabolite, β-hydroxy-β-methylbutyrate (HMB) suppresses apoptotic signaling and the apoptotic index (the ratio of apoptotic positive to apoptotic negative myonuclei) during muscle disuse and during reloading periods after disuse in aged rats. However, it was not clear if the apoptotic signaling indexes were due only to preservation of myonuclei or if perhaps the total myogenic pool increased as a result of HMB-mediated satellite cell proliferation as this would have also reduced the apoptotic index. In this study, we tested the hypothesis that HMB would augment myogenic cells (satellite cells) proliferation during muscle recovery (growth) after a period of disuse in senescent animals. The hindlimb muscles of 34 month old Fisher 344 × Brown Norway rats were unloaded for 14 days by hindlimb suspension (HLS), and then reloaded for 14 days. The rats received either Ca-HMB (340 mg/kg body weight; n = 16), or the vehicle (n = 10) by gavage throughout the experimental period. HMB prevented the functional decline in maximal plantar flexion isometric force production during the reloading period, but not during HLS. HMB-treatment enhanced the proliferation of muscle stem cells as shown by a greater percentage of satellite cells that had proliferated (more BrdU positive, Pax-7 positive, and more Pax7/Ki67 positive nuclei) and as a result, more differentiated stem cells were present (more MyoD/myogenin positive myonuclei), relative to total myonuclei, in reloaded plantaris muscles as compared to reloaded muscles from vehicle-treated animals. Furthermore HMB increased the nuclear protein abundance of proliferation markers, inhibitor of differentiation-2 and cyclin A, as compared to vehicle treatment in reloaded muscles. Although HMB increased phosphorylated Akt during reloading, other mTOR related proteins were not altered by HMB treatment. These data show that

  17. Simulated Microgravity and 3D Culture Enhance Induction, Viability, Proliferation and Differentiation of Cardiac Progenitors from Human Pluripotent Stem Cells

    PubMed Central

    Jha, Rajneesh; Wu, Qingling; Singh, Monalisa; Preininger, Marcela K.; Han, Pengcheng; Ding, Gouliang; Cho, Hee Cheol; Jo, Hanjoong; Maher, Kevin O.; Wagner, Mary B.; Xu, Chunhui

    2016-01-01

    Efficient generation of cardiomyocytes from human pluripotent stem cells is critical for their regenerative applications. Microgravity and 3D culture can profoundly modulate cell proliferation and survival. Here, we engineered microscale progenitor cardiac spheres from human pluripotent stem cells and exposed the spheres to simulated microgravity using a random positioning machine for 3 days during their differentiation to cardiomyocytes. This process resulted in the production of highly enriched cardiomyocytes (99% purity) with high viability (90%) and expected functional properties, with a 1.5 to 4-fold higher yield of cardiomyocytes from each undifferentiated stem cell as compared with 3D-standard gravity culture. Increased induction, proliferation and viability of cardiac progenitors as well as up-regulation of genes associated with proliferation and survival at the early stage of differentiation were observed in the 3D culture under simulated microgravity. Therefore, a combination of 3D culture and simulated microgravity can be used to efficiently generate highly enriched cardiomyocytes. PMID:27492371

  18. Non-cross-linked collagen type I/III materials enhance cell proliferation: in vitro and in vivo evidence

    PubMed Central

    WILLERSHAUSEN, Ines; BARBECK, Mike; BOEHM, Nicole; SADER, Robert; WILLERSHAUSEN, Brita; KIRKPATRICK, Charles James; GHANAATI, Shahram

    2014-01-01

    Objective To analyze Mucograft®(MG), a recently introduced collagen matrix, in vitro and in vivo, and compare it with BioGide®(BG), a well-established collagen membrane, as control. Material and Methods A detailed analysis of the materials surface and ultra-structure was performed. Cellular growth patterns and proliferation rates of human fibroblasts on MG and BG were analyzed in vitro. In addition, the early tissue reaction of CD-1 mouse to these materials was analyzed by means of histological and histomorphometrical analysis. Results MG showed a three-fold higher thickness both in dry and wet conditions, when compared to BG. The spongy surface of BG significantly differed from that of MG. Cells showed a characteristic proliferation pattern on the different materials in vitro. Fibroblasts tended to proliferate on the compact layers of both collagens, with the highest values on the compact side of BG. In vivo, at day three both materials demonstrated good tissue integration, with a mononuclear cell sheet of fibroblasts on all surfaces, however, without penetrating into the materials. Conclusions The findings of this study showed that MG and BG facilitate cell proliferation on both of their surfaces in vitro. In vivo, these two materials induce a comparable early tissue reaction, while serving as cell occlusive barriers. PMID:24626246

  19. Inosine strongly enhances proliferation of human C32 melanoma cells through PLC-PKC-MEK1/2-ERK1/2 and PI3K pathways.

    PubMed

    Soares, Ana Sofia; Costa, Vera Marisa; Diniz, Carmen; Fresco, Paula

    2015-01-01

    Malignant melanoma is the most deadly type of skin cancer. The lack of effective pharmacological approaches for this tumour can be related to the incomplete understanding of the pathophysiological mechanisms involved in melanoma cell proliferation. Adenosine has growth-promoting and growth inhibitory effects on tumour cells. We aimed to investigate effects of adenosine and its metabolic product, inosine, on human C32 melanoma cells and the signalling pathways involved. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) reduction and bromodeoxyuridine (BrdU) proliferation assays were used to evaluate adenosine, adenosine deaminase and inosine effects, in the absence or presence of adenosine receptor (AR), A3 AR and P2Y1 R antagonists and PLC, PKC, MEK1/2 and PI3K inhibitors. ERK1/2 levels were determined using an ELISA kit. Adenosine and inosine levels were quantified using an enzyme-coupled assay. Adenosine caused cell proliferation through AR activation. Adenosine deaminase increased inosine levels (nanomolar concentrations) on the extracellular space, in a time-dependent manner, inducing proliferation through A3 AR activation. Micromolar concentrations of inosine enhanced proliferation through A3 AR activation, causing an increase in ERK1/2 levels, and P2Y1 R activation via ENT-dependent mechanisms. We propose the simultaneous activation of PLC-PKC-MEK1/2-ERK1/2 and PI3K pathways as the main mechanism responsible for the proliferative effect elicited by inosine and its significant role in melanoma cancer progression.

  20. Psoralidin inhibits proliferation and enhances apoptosis of human esophageal carcinoma cells via NF-κB and PI3K/Akt signaling pathways

    PubMed Central

    Jin, Zhiliang; Yan, Wei; Jin, Hui; Ge, Changzheng; Xu, Yanhua

    2016-01-01

    Esophageal cancer is the most common gastrointestinal cancer. Psoralidin exhibits antioxidant, anti-apoptotic, anti-inflammatory and antitumor effects, which result in the inhibition of cancer formation. The present study aimed to investigate the effect of psoralidin on esophageal carcinoma proliferation and growth, and to elucidate its underlying mechanism of action. The effect of psoralidin on cell proliferation was investigated using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Using an annexin V-fluorescein isothiocyanate/propidium iodide apoptosis detection kit and 4′,6-diamidino-2-phenylindole staining assay, the present study demonstrated that psoralidin significantly enhanced apoptosis of human esophageal carcinoma Eca9706 cells. In addition, caspase-3 activity was analyzed with a caspase-3 colorimetric assay kit, while nuclear factor (NF)-κB activity and protein phosphatidylinositol 3-kinase (PI3K)/Akt expression were measured with an NF-κB enzyme-linked immunosorbent assay kit and western blot analysis, respectively. Eca9706 cells were treated with a PI3K agonist in order to investigate the mechanism of action of psoralidin. It was observed that psoralidin was able to decrease the proliferation and promote the cellular apoptosis of Eca9706 cells in a dose-dependent manner. Furthermore, psoralidin was also able to inhibit the caspase-3 activity of Eca9706 cells in a dose-dependent manner. In addition, psoralidin inhibited NF-κB activity and reduced PI3K and Akt protein expression in Eca9706 cells. Notably, the PI3K agonist was able to reverse the effect of psoralidin on Eca9706 cells. The results of the present study demonstrated that psoralidin was able to inhibit proliferation and enhance apoptosis of human esophageal carcinoma cells via the NF-κB and PI3K/Akt signaling pathways. PMID:27446379

  1. Protein kinase D1 stimulates proliferation and enhances tumorigenesis of MCF-7 human breast cancer cells through a MEK/ERK-dependent signaling pathway

    SciTech Connect

    Karam, Manale; Legay, Christine; Auclair, Christian; Ricort, Jean-Marc

    2012-03-10

    Protein kinase D1, PKD1, is a novel serine/threonine kinase whose altered expression and dysregulation in many tumors as well as its activation by several mitogens suggest that this protein could regulate proliferation and tumorigenesis. Nevertheless, the precise signaling pathways used are still unclear and the potential direct role of PKD1 in tumor development and progression has not been yet investigated. In order to clarify the role of PKD1 in cell proliferation and tumorigenesis, we studied the effects of PKD1 overexpression in a human adenocarcinoma breast cancer cell line, MCF-7 cells. We demonstrated that overexpression of PKD1 specifically promotes MCF-7 cell proliferation through accelerating G0/G1 to S phase transition of the cell cycle. Moreover, inhibition of endogenous PKD1 significantly reduced cell proliferation. Taken together, these results clearly strengthen the regulatory role of PKD1 in cell growth. We also demonstrated that overexpression of PKD1 specifically diminished serum- and anchorage-dependence for proliferation and survival in vitro and allowed MCF-7 cells to form tumors in vivo. Thus, all these data highlight the central role of PKD1 in biological processes which are hallmarks of malignant transformation. Analysis of two major signaling pathways implicated in MCF-7 cell proliferation showed that PKD1 overexpression significantly increased ERK1/2 phosphorylation state without affecting Akt phosphorylation. Moreover, PKD1 overexpression-stimulated cell proliferation and anchorage-independent growth were totally impaired by inhibition of the MEK/ERK kinase cascade. However, neither of these effects was affected by blocking the PI 3-kinase/Akt signaling pathway. Thus, the MEK/ERK signaling appears to be a determining pathway mediating the biological effects of PKD1 in MCF-7 cells. Taken together, all these data demonstrate that PKD1 overexpression increases the aggressiveness of MCF-7 breast cancer cells through enhancing their oncogenic

  2. Peroxisome Proliferator-activated Receptor γ Regulates Genes Involved in Insulin/Insulin-like Growth Factor Signaling and Lipid Metabolism during Adipogenesis through Functionally Distinct Enhancer Classes*

    PubMed Central

    Oger, Frédérik; Dubois-Chevalier, Julie; Gheeraert, Céline; Avner, Stéphane; Durand, Emmanuelle; Froguel, Philippe; Salbert, Gilles; Staels, Bart; Lefebvre, Philippe; Eeckhoute, Jérôme

    2014-01-01

    The nuclear receptor peroxisome proliferator-activated receptor (PPAR) γ is a transcription factor whose expression is induced during adipogenesis and that is required for the acquisition and control of mature adipocyte functions. Indeed, PPARγ induces the expression of genes involved in lipid synthesis and storage through enhancers activated during adipocyte differentiation. Here, we show that PPARγ also binds to enhancers already active in preadipocytes as evidenced by an active chromatin state including lower DNA methylation levels despite higher CpG content. These constitutive enhancers are linked to genes involved in the insulin/insulin-like growth factor signaling pathway that are transcriptionally induced during adipogenesis but to a lower extent than lipid metabolism genes, because of stronger basal expression levels in preadipocytes. This is consistent with the sequential involvement of hormonal sensitivity and lipid handling during adipocyte maturation and correlates with the chromatin structure dynamics at constitutive and activated enhancers. Interestingly, constitutive enhancers are evolutionary conserved and can be activated in other tissues, in contrast to enhancers controlling lipid handling genes whose activation is more restricted to adipocytes. Thus, PPARγ utilizes both broadly active and cell type-specific enhancers to modulate the dynamic range of activation of genes involved in the adipogenic process. PMID:24288131

  3. 50-Hz extremely low frequency electromagnetic fields enhance cell proliferation and DNA damage: possible involvement of a redox mechanism.

    PubMed

    Wolf, Federica I; Torsello, Angela; Tedesco, Beatrice; Fasanella, Silvia; Boninsegna, Alma; D'Ascenzo, Marcello; Grassi, Claudio; Azzena, Gian Battista; Cittadini, Achille

    2005-03-22

    HL-60 leukemia cells, Rat-1 fibroblasts and WI-38 diploid fibroblasts were exposed for 24-72 h to 0.5-1.0-mT 50-Hz extremely low frequency electromagnetic field (ELF-EMF). This treatment induced a dose-dependent increase in the proliferation rate of all cell types, namely about 30% increase of cell proliferation after 72-h exposure to 1.0 mT. This was accompanied by increased percentage of cells in the S-phase after 12- and 48-h exposure. The ability of ELF-EMF to induce DNA damage was also investigated by measuring DNA strand breaks. A dose-dependent increase in DNA damage was observed in all cell lines, with two peaks occurring at 24 and 72 h. A similar pattern of DNA damage was observed by measuring formation of 8-OHdG adducts. The effects of ELF-EMF on cell proliferation and DNA damage were prevented by pretreatment of cells with an antioxidant like alpha-tocopherol, suggesting that redox reactions were involved. Accordingly, Rat-1 fibroblasts that had been exposed to ELF-EMF for 3 or 24 h exhibited a significant increase in dichlorofluorescein-detectable reactive oxygen species, which was blunted by alpha-tocopherol pretreatment. Cells exposed to ELF-EMF and examined as early as 6 h after treatment initiation also exhibited modifications of NF kappa B-related proteins (p65-p50 and I kappa B alpha), which were suggestive of increased formation of p65-p50 or p65-p65 active forms, a process usually attributed to redox reactions. These results suggest that ELF-EMF influence proliferation and DNA damage in both normal and tumor cells through the action of free radical species. This information may be of value for appraising the pathophysiologic consequences of an exposure to ELF-EMF.

  4. Enhanced proliferation of coronary endothelial cells in response to growth factors is synergized by hemodialysate compounds in vitro.

    PubMed

    Schönwald, D; Sixt, B; Machicao, F; Marx, E; Haedenkamp, G; Bertsch, S

    1991-01-01

    Using capillary endothelial cells from the coronary system of guinea pig heart, we have devised an in vitro assay suitable for measuring proliferative and growth-promoting effects mediated by drugs and growth factors. In this assay, hemodialysate and fractions isolated from it--consisting exclusively of low-molecular-weight compounds from calf blood--stimulate the proliferation of coronary endothelial cells. This effect is not a trivial nutritive one. Furthermore, in respect to the stimulation of proliferation, hemodialysate synergizes with epidermal growth factor, basic fibroblast growth factor, and endothelial cell growth factor, but not with insulin, which shows no proliferative effect in our system. From data obtained by analysis of hemodialysate fractions, it is deduced that the active compounds are strongly negatively charged oligosaccharides with a molecular weight of apparently 3000 Dalton. The synergistic effect of hemodialysate compounds on proliferation of endothelial cells as well as their previously demonstrated insulin-like activity is believed to explain the therapeutic efficacy of hemodialysate in cases of impaired wound healing and occlusive diseases.

  5. Sonic hedgehog-induced type 3 deiodinase blocks thyroid hormone action enhancing proliferation of normal and malignant keratinocytes.

    PubMed

    Dentice, Monica; Luongo, Cristina; Huang, Stephen; Ambrosio, Raffaele; Elefante, Antonia; Mirebeau-Prunier, Delphine; Zavacki, Ann Marie; Fenzi, Gianfranco; Grachtchouk, Marina; Hutchin, Mark; Dlugosz, Andrzej A; Bianco, Antonio C; Missero, Caterina; Larsen, P Reed; Salvatore, Domenico

    2007-09-04

    The Sonic hedgehog (Shh) pathway plays a critical role in hair follicle physiology and is constitutively active in basal cell carcinomas (BCCs), the most common human malignancy. Type 3 iodothyronine deiodinase (D3), the thyroid hormone-inactivating enzyme, is frequently expressed in proliferating and neoplastic cells, but its role in this context is unknown. Here we show that Shh, through Gli2, directly induces D3 in proliferating keratinocytes and in mouse and human BCCs. We demonstrate that Gli-induced D3 reduces intracellular active thyroid hormone, thus resulting in increased cyclin D1 and keratinocyte proliferation. D3 knockdown caused a 5-fold reduction in the growth of BCC xenografts in nude mice. Shh-induced thyroid hormone degradation via D3 synergizes with the Shh-mediated reduction of the type 2 deiodinase, the thyroxine-activating enzyme, and both effects are reversed by cAMP. This previously unrecognized functional cross-talk between Shh/Gli2 and thyroid hormone in keratinocytes is a pathway by which Shh produces its proliferative effects and offers a potential therapeutic approach to BCC.

  6. Estrogen promotes fat mass and obesity-associated protein nuclear localization and enhances endometrial cancer cell proliferation via the mTOR signaling pathway.

    PubMed

    Zhu, Yaping; Shen, Jiaqi; Gao, Liyan; Feng, Youji

    2016-04-01

    Extensive exposure to estrogen is generally acknowledged as a risk factor for endometrial cancer. Given that the accumulation of adipocytes also contributes to the increased production of estrogen, in the present study, we evaluated the expression of the fat mass and obesity-associated (FTO) gene in endometrial tumor tissues and further explored the mechanism of how estrogen facilitates FTO nuclear localization and promotes endometrial cancer cell proliferation. Immunohistochemical (IHC) staining assay was used to detect the FTO expression in endometrial tumor samples. Western blotting was performed to investigate the mechanism of estrogen-induced FTO nuclear localization. siRNA was used to knock down ERα and further explore its role in FTO nuclear localization. MTT assay was carried out to determine cell proliferation. We found that FTO was overexpressed in endometrial carcinoma tissues and served as a poor prognostic marker. Additionally, estrogen induced FTO nuclear accumulation via the mTOR signaling pathway and the nuclear localization was ERα-dependent, which contributed to enhanced proliferative activity. Therefore, the present study provides new insight into the mechanisms of estrogen-induced proliferation, implying the possibility of using FTO as a potential therapeutic target for the treatment of endometrial cancer.

  7. NES1/KLK10 gene represses proliferation, enhances apoptosis and down-regulates glucose metabolism of PC3 prostate cancer cells

    PubMed Central

    Hu, Jiajia; Lei, Hu; Fei, Xiaochun; Liang, Sheng; Xu, Hanzhang; Qin, Dongjun; Wang, Yue; Wu, Yingli; Li, Biao

    2015-01-01

    The normal epithelial cell-specific-1 (NES1) gene, also named as KLK10, is recognised as a novel putative tumour suppressor in breast cancer, but few studies have focused on the function of KLK10 in human prostate cancer. Our study confirms that the expression of KLK10 in prostate cancer tissue and cell lines (PC3, DU145, and LNCaP clone FGC) is low. Given that the androgen-independent growth characteristic of the PC3 cell line is more similar to clinical castration-resistant prostate cancer, we studied the role of KLK10 in PC3. In vitro and in vivo assays showed that over-expressing KLK10 in PC3 could decelerate tumour proliferation, which was accompanied with an increase in apoptosis and suppression of glucose metabolism. The related proteins, such as Bcl-2 and HK-2, were down-regulated subsequently. Furthermore, by up-regulating Bcl-2 or HK-2 respectively in the PC3-KLK10 cell line, we observed a subsequent increase of cell proliferation and a synchronous up-regulation of HK-2 and Bcl-2. Besides, KLK10 expression was also increased by Bcl-2 and HK-2, which suggests that there is a negative feedback loop between KLK10 and Bcl-2/HK-2. Thus, our results demonstrated that KLK10 may function as a tumour suppressor by repressing proliferation, enhancing apoptosis and decreasing glucose metabolism in PC3 cells. PMID:26616394

  8. NES1/KLK10 gene represses proliferation, enhances apoptosis and down-regulates glucose metabolism of PC3 prostate cancer cells.

    PubMed

    Hu, Jiajia; Lei, Hu; Fei, Xiaochun; Liang, Sheng; Xu, Hanzhang; Qin, Dongjun; Wang, Yue; Wu, Yingli; Li, Biao

    2015-11-30

    The normal epithelial cell-specific-1 (NES1) gene, also named as KLK10, is recognised as a novel putative tumour suppressor in breast cancer, but few studies have focused on the function of KLK10 in human prostate cancer. Our study confirms that the expression of KLK10 in prostate cancer tissue and cell lines (PC3, DU145, and LNCaP clone FGC) is low. Given that the androgen-independent growth characteristic of the PC3 cell line is more similar to clinical castration-resistant prostate cancer, we studied the role of KLK10 in PC3. In vitro and in vivo assays showed that over-expressing KLK10 in PC3 could decelerate tumour proliferation, which was accompanied with an increase in apoptosis and suppression of glucose metabolism. The related proteins, such as Bcl-2 and HK-2, were down-regulated subsequently. Furthermore, by up-regulating Bcl-2 or HK-2 respectively in the PC3-KLK10 cell line, we observed a subsequent increase of cell proliferation and a synchronous up-regulation of HK-2 and Bcl-2. Besides, KLK10 expression was also increased by Bcl-2 and HK-2, which suggests that there is a negative feedback loop between KLK10 and Bcl-2/HK-2. Thus, our results demonstrated that KLK10 may function as a tumour suppressor by repressing proliferation, enhancing apoptosis and decreasing glucose metabolism in PC3 cells.

  9. Downregulation of microRNA-15b by hepatitis B virus X enhances hepatocellular carcinoma proliferation via fucosyltransferase 2-induced Globo H expression.

    PubMed

    Wu, Chen-Shiou; Yen, Chia-Jui; Chou, Ruey-Hwang; Chen, Jia-Ni; Huang, Wei-Chien; Wu, Chung-Yi; Yu, Yung-Luen

    2014-04-01

    Globo H, a cancer-associated carbohydrate antigen, is highly expressed in various types of cancers. However, the role of Globo H in hepatocellular carcinoma (HCC) remains elusive. In our study, we performed glycan microarray analysis of 134 human serum samples to explore anti-Globo H antibody changes and found that Globo H is upregulated in hepatitis B virus (HBV)-positive HCC. Similarly, immunohistochemistry showed that Globo H expression was higher in tumors compared to normal tissues. In addition, fucosyltransferase 2 (FUT2), the main synthetic enzyme of Globo H, was also increased in HCC cells overexpressing HBV X protein (HBX). HBX plays an important role in promoting cell proliferation and may be related to increased levels of FUT2 and Globo H. Furthermore, using microRNA profiling, we observed that microRNA-15b (miR-15b) was downregulated in patients with HCC and confirmed association of FUT2 expression with expression of its product, Globo H. Therefore, our results suggest that HBX suppressed the expression of miR-15b, which directly targeted FUT2 and then increased levels of Globo H to enhance HCC cell proliferation. Additionally, proliferation of HBX-overexpressing HCC cells was significantly inhibited by treatment with Globo H antibody in vitro. In xenograft animal experiments, we found that overexpression of miR-15b effectively suppressed tumor growth. The newly identified HBX/miR-15b/FUT2/Globo H axis suggests one possible molecular mechanism of HCC cell proliferation and represents a new potential therapeutic target for HCC treatment.

  10. Substance P enhances the proliferation and migration potential of murine bone marrow-derived mesenchymal stem cell-like cell lines.

    PubMed

    Dubon, Maria Jose; Park, Ki-Sook

    2015-04-01

    Due to the therapeutic characteristics of bone marrow (BM)-derived mesenchymal stem cells (MSCs), clinical trials are testing the use of autologous or allogeneic MSCs for the treatment of several conditions. These therapies require large numbers of MSCs and numerous studies are attempting to find substances that could enhance the egression of endogenous MSCs from the BM into the periphery and increase their proliferation in vivo and in vitro. It has been reported that substance P (SP) has the potential to increase the expansion of MSCs in vivo and to induce their mobilization from the BM into the periphery. The aim of the present study was to investigate the effects of SP on the migration and proliferation potential of two BM-derived MSC-like cell lines, ST2 and OP9. SP was found to induce the migration potential of ST2 cells in vitro. Furthermore, SP increased the proliferation of the MSCs cell line, OP9 cell line. Cyclin D1 expression was observed to increase in the OP9 cells, indicating the activation of the cell cycle in response to SP. The upstream signals involved in these phenomena have yet to be elucidated, although previous studies have proposed the activation of the extracellular signal-regulated kinase-1/2 and Wingless/β-catenin pathways as possible mediators of the cellular proliferation of human MSCs in response to SP. The present results therefore suggest that SP would facilitate the obtainment of higher numbers of endogenous MSCs from patients or donors and/or shorten the process of in vitro expansion that could cause the MSCs to undergo changes in their innate therapeutic characteristics prior to their use in therapy.

  11. Long interspersed nucleotide acid element-1 ORF-1 protein promotes proliferation and invasion of human colorectal cancer LoVo cells through enhancing ETS-1 activity.

    PubMed

    Li, M Y; Zhu, M; Feng, F; Cai, F Y; Fan, K C; Jiang, H; Wang, Z Q; Linghu, E Q

    2014-04-14

    The human proto-oncogene long interspersed nucleotide acid element-1 (LINE-1) open reading frame-1 protein (ORF-1p) is involved in the progress of several cancers. The transcription factor ETS-1 can mediate the transcription of some downstream genes that play specific roles in the regulation of cancerous cell invasion and metastasis. In this study, the effects of LINE-1 ORF-1p on ETS-1 activity and on the proliferation and invasion of human colorectal cancer LoVo cells were investigated. Results showed that the overexpression of LINE-1 ORF-1p enhanced the transcription of ETS-1 downstream genes and increased their protein levels, and downregulation of the LINE-1 ORF-1p level by small interfering RNA (siRNA) reduced the transcriptional activation of ETS-1. In addition, overexpression of LINE-1 ORF-1p promoted LoVo cell proliferation and anchor-independent growth, and a knockdown of the LINE-1 protein level by siRNA reduced the proliferation and anchor-independent growth ability of LoVo cells. In vivo data revealed that LINE-1 ORF-1p overexpression increased LoVo tumor growth in nude mice, whereas the siRNA knockdown of endogenous LINE-1 ORF-1p expression decreased LoVo cell growth in nude mice. Therefore, LINE- 1 ORF-1p could promote LoVo cell proliferation and invasion both in vitro and in vivo, indicating that it might be a useful molecular target for the treatment of human colorectal cancer.

  12. Pueraria mirifica extract and puerarin enhance proliferation and expression of alkaline phosphatase and type I collagen in primary baboon osteoblasts.

    PubMed

    Tiyasatkulkovit, Wacharaporn; Malaivijitnond, Suchinda; Charoenphandhu, Narattaphol; Havill, Lorena M; Ford, Allen L; VandeBerg, John L

    2014-10-15

    Phytoestrogen-rich Pueraria mirifica (PM) tuberous extract is a promising candidate for the development of anti-osteoporosis drugs for postmenopausal women, but its action has never been validated in humans or in non-human primates, which are more closely related to humans than rodents. In vitro study of non-human primate osteoblasts is thus fundamental to prepare for in vivo studies of phytoestrogen effects on primate bone. This study aimed to establish a culture system of baboon primary osteoblasts and to investigate the effects of PM extract and its phytoestrogens on these cells. Primary osteoblasts from adult baboon fibulae exhibited osteoblast characteristics in regard to proliferation, differentiation, mineralization, and estrogen receptor expression. They responded to 17β-estradiol by increased proliferation rate and mRNA levels of alkaline phosphatase (ALP), type I collagen, and osteocalcin. After being exposed for 48 h to 100 μg/ml PM extract, 1000 nM genistein, or 1000 nM puerarin, primary baboon osteoblasts markedly increased the rate of proliferation and mRNA levels of ALP and type I collagen without changes in Runx2, osterix, or osteocalcin expression. PM extract, genistein, and puerarin also decreased the RANKL/OPG ratio, suggesting that they could decrease osteoclast-mediated bone resorption. However, neither PM extract nor its phytoestrogens altered calcium deposition in osteoblast culture. In conclusion, we have established baboon primary osteoblast culture, which is a new tool for bone research and drug discovery. Furthermore, the present results provide substantial support for the potential of PM extract and its phytoestrogens to be developed as therapeutic agents against bone fragility.

  13. Transcription factor activity of estrogen receptor α activation upon nonylphenol or bisphenol A treatment enhances the in vitro proliferation, invasion, and migration of neuroblastoma cells

    PubMed Central

    Ma, Hongda; Yao, Yao; Wang, Changli; Zhang, Liyu; Cheng, Long; Wang, Yiren; Wang, Tao; Liang, Erguang; Jia, Hui; Ye, Qinong; Hou, Mingxiao; Feng, Fan

    2016-01-01

    Many kinds of endocrine-disrupting chemicals (EDCs), for example, the environmental estrogens bisphenol A and nonylphenol, may regulate the activity of estrogen receptor α (ERα) and therefore induce potential disruption of normal endocrine function. However, the involvement of EDCs in human cancers, especially in endocrine-related cancer neuroblastoma regulation, is not very clear. In this work, results showed that upon bisphenol A or nonylphenol treatment, the transcription factor activity of ERα was significantly increased in neuroblastoma cell line SH-SY5Y. Bisphenol A and nonylphenol could enhance ERα activity via recruiting it to the target gene promoter. Furthermore, treatment of bisphenol A and nonylphenol enhanced the in vitro proliferation, invasion, and migration ability of neuroblastoma cells. By investigating the role of EDC-induced ERα upregulation, our data extend the understanding of the function of EDCs and further suggest that ERα might be a potential therapeutic target in human neuroblastoma treatment. PMID:27366082

  14. Pharmacological Administration of the Isoflavone Daidzein Enhances Cell Proliferation and Reduces High Fat Diet-Induced Apoptosis and Gliosis in the Rat Hippocampus

    PubMed Central

    Rivera, Patricia; Pérez-Martín, Margarita; Pavón, Francisco J.; Serrano, Antonia; Crespillo, Ana; Cifuentes, Manuel; López-Ávalos, María-Dolores; Grondona, Jesús M.; Vida, Margarita; Fernández-Llebrez, Pedro; de Fonseca, Fernando Rodríguez; Suárez, Juan

    2013-01-01

    Soy extracts have been claimed to be neuroprotective against brain insults, an effect related to the estrogenic properties of isoflavones. However, the effects of individual isoflavones on obesity-induced disruption of adult neurogenesis have not yet been analyzed. In the present study we explore the effects of pharmacological administration of daidzein, a main soy isoflavone, in cell proliferation, cell apoptosis and gliosis in the adult hippocampus of animals exposed to a very high-fat diet. Rats made obese after 12-week exposure to a standard or high-fat (HFD, 60%) diets were treated with daidzein (50 mg kg−1) for 13 days. Then, plasma levels of metabolites and metabolic hormones, cell proliferation in the subgranular zone of the dentate gyrus (SGZ), and immunohistochemical markers of hippocampal cell apoptosis (caspase-3), gliosis (GFAP and Iba-1), food reward factor FosB and estrogen receptor alpha (ERα) were analyzed. Treatment with daidzein reduced food/caloric intake and body weight gain in obese rats. This was associated with glucose tolerance, low levels of HDL-cholesterol, insulin, adiponectin and testosterone, and high levels of leptin and 17β-estradiol. Daidzein increased the number of phospho-histone H3 and 5-bromo-2-deoxyuridine (BrdU)-ir cells detected in the SGZ of standard diet and HFD-fed rats. Daidzein reversed the HFD-associated enhanced immunohistochemical expression of caspase-3, FosB, GFAP, Iba-1 and ERα in the hippocampus, being more prominent in the dentate gyrus. These results suggest that pharmacological treatment with isoflavones regulates metabolic alterations associated with enhancement of cell proliferation and reduction of apoptosis and gliosis in response to high-fat diet. PMID:23741384

  15. Pharmacological administration of the isoflavone daidzein enhances cell proliferation and reduces high fat diet-induced apoptosis and gliosis in the rat hippocampus.

    PubMed

    Rivera, Patricia; Pérez-Martín, Margarita; Pavón, Francisco J; Serrano, Antonia; Crespillo, Ana; Cifuentes, Manuel; López-Ávalos, María-Dolores; Grondona, Jesús M; Vida, Margarita; Fernández-Llebrez, Pedro; de Fonseca, Fernando Rodríguez; Suárez, Juan

    2013-01-01

    Soy extracts have been claimed to be neuroprotective against brain insults, an effect related to the estrogenic properties of isoflavones. However, the effects of individual isoflavones on obesity-induced disruption of adult neurogenesis have not yet been analyzed. In the present study we explore the effects of pharmacological administration of daidzein, a main soy isoflavone, in cell proliferation, cell apoptosis and gliosis in the adult hippocampus of animals exposed to a very high-fat diet. Rats made obese after 12-week exposure to a standard or high-fat (HFD, 60%) diets were treated with daidzein (50 mg kg(-1)) for 13 days. Then, plasma levels of metabolites and metabolic hormones, cell proliferation in the subgranular zone of the dentate gyrus (SGZ), and immunohistochemical markers of hippocampal cell apoptosis (caspase-3), gliosis (GFAP and Iba-1), food reward factor FosB and estrogen receptor alpha (ERα) were analyzed. Treatment with daidzein reduced food/caloric intake and body weight gain in obese rats. This was associated with glucose tolerance, low levels of HDL-cholesterol, insulin, adiponectin and testosterone, and high levels of leptin and 17β-estradiol. Daidzein increased the number of phospho-histone H3 and 5-bromo-2-deoxyuridine (BrdU)-ir cells detected in the SGZ of standard diet and HFD-fed rats. Daidzein reversed the HFD-associated enhanced immunohistochemical expression of caspase-3, FosB, GFAP, Iba-1 and ERα in the hippocampus, being more prominent in the dentate gyrus. These results suggest that pharmacological treatment with isoflavones regulates metabolic alterations associated with enhancement of cell proliferation and reduction of apoptosis and gliosis in response to high-fat diet.

  16. Human YKL39 (chitinase 3-like protein 2), an osteoarthritis-associated gene, enhances proliferation and type II collagen expression in ATDC5 cells

    SciTech Connect

    Miyatake, Kazumasa; Tsuji, Kunikazu; Yamaga, Mika; Yamada, Jun; Matsukura, Yu; Abula, Kahaer; Sekiya, Ichiro; Muneta, Takeshi

    2013-02-01

    Highlights: ► hYKL-39 expression is increased in osteoarthritic articular chondrocytes. ► To examine the molecular functions of hYKL-39 in chondrocytes, we overexpressed hYKL-39 in chondrocytic ATDC5 cells. ► hYKL-39 enhanced proliferation and colony formation in ATDC5 cells. ► hYKL-39 increased type II collagen expression in ATDC5 cells treated with chondrogenic medium. -- Abstract: Human YKL39 (chitinase 3-like protein 2/CHI3L2) is a secreted 39 kDa protein produced by articular chondrocytes and synoviocytes. Recent studies showed that hYKL-39 expression is increased in osteoarthritic articular chondrocytes suggesting the involvement of hYKL-39 in the progression of osteoarthritis (OA). However little is known regarding the molecular function of hYKL-39 in joint homeostasis. Sequence analyses indicated that hYKL-39 has significant identity with the human chitotorisidase family molecules, although it is considered that hYKL-39 has no enzymatic activity since it lacks putative chitinase catalytic motif. In this study, to examine the molecular function of hYKL-39 in chondrocytes, we overexpressed hYKL-39 in ATDC5 cells. Here we report that hYKL-39 enhances colony forming activity, cell proliferation, and type II collagen expression in these cells. These data suggest that hYKL-39 is a novel growth and differentiation factor involved in cartilage homeostasis.

  17. CXCL14 enhances proliferation and migration of NCI-H460 human lung cancer cells overexpressing the glycoproteins containing heparan sulfate or sialic acid.

    PubMed

    Park, Cho Rong; You, Dong-Joo; Kim, Dong-Kyu; Moon, Mi Jin; Lee, Cheolju; Oh, Seung-Hyun; Ahn, Curie; Seong, Jae Young; Hwang, Jong-Ik

    2013-05-01

    CXCL14 is a chemokine family member that is involved in various cellular responses in addition to immune cell activation. Although constitutive CXCL14 expression in normal epithelial cells may help protect against infection by activating immune systems, its expression in cancer cells has raised controversy regarding its possible role in tumorigenesis. However, the underlying mechanisms for this disparity remain unknown. Investigation of cellular CXCL14 binding properties might increase our understanding of the peptide's roles in tumorigenesis. In the present study, we found that CXCL14 binds to various cell types. Interestingly, binding to NCI-H460 cells was prevented by heparan sulfate and N-acetyl neuraminic acid. Next, we examined effect of CXCL14 binding in NCI-H460 and NCI-H23. CXCL14 enhanced proliferation and migration in NCI-H460 but had no effect on NCI-H23. A reporter gene assay with various transcription factor response elements revealed that only nuclear factor-κB (NF-κB) signaling was activated by CXCL14 in NCI-H460 cells, which was blocked by BAPTA-AM, TPCA-1, and brefeldin A. Exogenous expression of some glycoproteins such as syndecan-4, podoplanin, and CD43 in these cells enhanced CXCL14 binding and NF-κB activity. Collectively, these results demonstrate that CXCL14 binding to glycoproteins harboring heparan sulfate proteoglycans and sialic acids leads proliferation and migration of some cancer cells.

  18. Inhibition of glycogen synthase kinase-3 enhances the differentiation and reduces the proliferation of adult human olfactory epithelium neural precursors

    SciTech Connect

    Manceur, Aziza P.; Tseng, Michael; Holowacz, Tamara; Witterick, Ian; Weksberg, Rosanna; McCurdy, Richard D.; Warsh, Jerry J.; Audet, Julie

    2011-09-10

    The olfactory epithelium (OE) contains neural precursor cells which can be easily harvested from a minimally invasive nasal biopsy, making them a valuable cell source to study human neural cell lineages in health and disease. Glycogen synthase kinase-3 (GSK-3) has been implicated in the etiology and treatment of neuropsychiatric disorders and also in the regulation of murine neural precursor cell fate in vitro and in vivo. In this study, we examined the impact of decreased GSK-3 activity on the fate of adult human OE neural precursors in vitro. GSK-3 inhibition was achieved using ATP-competitive (6-bromoindirubin-3'-oxime and CHIR99021) or substrate-competitive (TAT-eIF2B) inhibitors to eliminate potential confounding effects on cell fate due to off-target kinase inhibition. GSK-3 inhibitors decreased the number of neural precursor cells in OE cell cultures through a reduction in proliferation. Decreased proliferation was not associated with a reduction in cell survival but was accompanied by a reduction in nestin expression and a substantial increase in the expression of the neuronal differentiation markers MAP1B and neurofilament (NF-M) after 10 days in culture. Taken together, these results suggest that GSK-3 inhibition promotes the early stages of neuronal differentiation in cultures of adult human neural precursors and provide insights into the mechanisms by which alterations in GSK-3 signaling affect adult human neurogenesis, a cellular process strongly suspected to play a role in the etiology of neuropsychiatric disorders.

  19. Controlled Delivery of Extracellular ROS Based on Hematoporphyrin-Incorporated Polyurethane Film for Enhanced Proliferation of Endothelial Cells.

    PubMed

    Koo, Min-Ah; Kim, Bong-Jin; Lee, Mi Hee; Kwon, Byeong-Ju; Kim, Min Sung; Seon, Gyeung Mi; Kim, Dohyun; Nam, Ki Chang; Wang, Kangkyun; Kim, Yong-Rok; Park, Jong-Chul

    2016-10-04

    The principle of photodynamic treatment (PDT) involves the administration of photosensitizer (PS) at diseased tissues, followed by light irradiation to produce reactive oxygen species (ROS). In cells, a moderate increase in ROS plays an important role as signaling molecule to promote cell proliferation, whereas a severe increase of ROS causes cell damage. Previous studies have shown that low levels of ROS stimulate cell growth through PS drugs-treating PDT and non-thermal plasma treatment. However, these methods have side effects which are associated with low tissue selectivity and remaining of PS residues. To overcome such shortcomings, we designed hematoporphyrin-incorporated polyurethane (PU) film induced generation of extracellular ROS with singlet oxygen and free radicals. The film can easily control ROS production rate by regulating several parameters including light dose, PS dose. Also, its use facilitates targeted delivery of ROS to the specific lesion. Our study demonstrated that extracellular ROS could induce the formation of intracellular ROS. In vascular endothelial cells, a moderated increase in intracellular ROS also stimulated cell proliferation and cell cycle progression by accurate control of optimum levels of ROS with hematoporphyrin-incorporated polymer films. This modulation of cellular growth is expected to be an effective strategy for the design of next generation PDT.

  20. Proinflammatory Macrophages Enhance the Regenerative Capacity of Human Myoblasts by Modifying Their Kinetics of Proliferation and Differentiation

    PubMed Central

    Bencze, Maximilien; Negroni, Elisa; Vallese, Denis; Yacoub–Youssef, Houda; Chaouch, Soraya; Wolff, Annie; Aamiri, Ahmed; Di Santo, James P; Chazaud, Bénédicte; Butler-Browne, Gillian; Savino, Wilson; Mouly, Vincent; Riederer, Ingo

    2012-01-01

    Macrophages have been shown to be essential for muscle repair by delivering trophic cues to growing skeletal muscle precursors and young fibers. Here, we investigated whether human macrophages, either proinflammatory or anti-inflammatory, coinjected with human myoblasts into regenerating muscle of Rag2−/− γC−/− immunodeficient mice, could modify in vivo the kinetics of proliferation and differentiation of the transplanted human myogenic precursors. Our results clearly show that proinflammatory macrophages improve in vivo the participation of injected myoblasts to host muscle regeneration, extending the window of proliferation, increasing migration, and delaying differentiation. Interestingly, immunostaining of transplanted proinflammatory macrophages at different time points strongly suggests that these cells are able to switch to an anti-inflammatory phenotype in vivo, which then may stimulate differentiation during muscle regeneration. Conceptually, our data provide for the first time in vivo evidence strongly suggesting that proinflammatory macrophages play a supportive role in the regulation of myoblast behavior after transplantation into preinjured muscle, and could thus potentially optimize transplantation of myogenic progenitors in the context of cell therapy. PMID:23070116

  1. Proinflammatory macrophages enhance the regenerative capacity of human myoblasts by modifying their kinetics of proliferation and differentiation.

    PubMed

    Bencze, Maximilien; Negroni, Elisa; Vallese, Denis; Yacoub-Youssef, Houda; Chaouch, Soraya; Wolff, Annie; Aamiri, Ahmed; Di Santo, James P; Chazaud, Bénédicte; Butler-Browne, Gillian; Savino, Wilson; Mouly, Vincent; Riederer, Ingo

    2012-11-01

    Macrophages have been shown to be essential for muscle repair by delivering trophic cues to growing skeletal muscle precursors and young fibers. Here, we investigated whether human macrophages, either proinflammatory or anti-inflammatory, coinjected with human myoblasts into regenerating muscle of Rag2(-/-) γC(-/-) immunodeficient mice, could modify in vivo the kinetics of proliferation and differentiation of the transplanted human myogenic precursors. Our results clearly show that proinflammatory macrophages improve in vivo the participation of injected myoblasts to host muscle regeneration, extending the window of proliferation, increasing migration, and delaying differentiation. Interestingly, immunostaining of transplanted proinflammatory macrophages at different time points strongly suggests that these cells are able to switch to an anti-inflammatory phenotype in vivo, which then may stimulate differentiation during muscle regeneration. Conceptually, our data provide for the first time in vivo evidence strongly suggesting that proinflammatory macrophages play a supportive role in the regulation of myoblast behavior after transplantation into preinjured muscle, and could thus potentially optimize transplantation of myogenic progenitors in the context of cell therapy.

  2. Enhancement of amygdalin activated with β-D-glucosidase on HepG2 cells proliferation and apoptosis.

    PubMed

    Zhou, Cunshan; Qian, Lichun; Ma, Haile; Yu, Xiaojie; Zhang, Youzuo; Qu, Wenjuan; Zhang, Xiaoxu; Xia, Wei

    2012-09-01

    The growth inhibition and induction of apoptosis brought by amygdalin and activated with β-D-glucosidase were tested for cytoactivity in HepG2 cells. The MTT viability assay showed that all samples had effects on HepG2 proliferation in dose and time response manners. IC50 of stand-alone amygdalin and activation with β-D-glucosidase on the proliferation of HepG2 cells for 48 h were 458.10 mg/mL and 3.2 mg/mL, respectively. Moreover, apoptotic cells were determined by AO/EB (acridine orange/ethidium bromide) fluorescent staining method and Annexin V-FITC/PI staining flow cytometry cell cycle analysis. With increasing of amygdalin concentration and the incubation time, the apoptotic rate was heightened. Compared with the control, there was significant difference (p<0.01). Together, these findings indicate that amygdalin had no strong anti-HepG2 activity; however the ingredients of amygdalin activated with β-D-glucosidase had a higher and efficient anti-HepG2 activity. It was therefore suggested that this combination strategy may be applicable for treating tumors with a higher activity.

  3. Myosin 1e promotes breast cancer malignancy by enhancing tumor cell proliferation and stimulating tumor cell de-differentiation

    PubMed Central

    Ouderkirk-Pecone, Jessica L.; Goreczny, Gregory J.; Chase, Sharon E.; Tatum, Arthur H.; Turner, Christopher E.; Krendel, Mira

    2016-01-01

    Despite advancing therapies, thousands of women die every year of breast cancer. Myosins, actin-dependent molecular motors, are likely to contribute to tumor formation and metastasis via their effects on cell adhesion and migration and may provide promising new targets for cancer therapies. Using the MMTV-PyMT murine model of breast cancer, we identified Myosin 1e (MYO1E) as a novel tumor promoter. Tumor latency in mice lacking MYO1E was significantly increased, and tumors formed in the absence of MYO1E displayed unusual papillary morphology, with well-differentiated layers of epithelial cells covering fibrovascular cores, rather than solid sheets of tumor cells typically observed in this cancer model. These tumors were reminiscent of papillary breast cancer in humans that is typically non-invasive and often cured by tumor excision. MYO1E-null tumors exhibited decreased expression of the markers of cell proliferation, which was recapitulated in primary tumor cells derived from MYO1E-null mice. In agreement with our findings, meta-analysis of patient survival data indicated that MYO1E expression level was associated with reduced recurrence-free survival in basal-like breast cancer. Overall, our data suggests that MYO1E contributes to breast tumor malignancy and regulates the differentiation and proliferation state of breast tumor cells. PMID:27329840

  4. Riluzole enhances expression of brain-derived neurotrophic factor with consequent proliferation of granule precursor cells in the rat hippocampus.

    PubMed

    Katoh-Semba, Ritsuko; Asano, Tomiko; Ueda, Hiroshi; Morishita, Rika; Takeuchi, Ikuo K; Inaguma, Yutaka; Kato, Kanefusa

    2002-08-01

    The dentate gyrus of the hippocampus, generating new cells throughout life, is essential for normal recognition memory performance. Reduction of brain-derived neurotrophic factor (BDNF) in this structure impairs its functions. To elucidate the association between BDNF levels and hippocampal neurogenesis, we first conducted a search for compounds that stimulate endogenous BDNF production in hippocampal granule neurons. Among ion channel modulators tested, riluzole, a neuroprotective agent with anticonvulsant properties that is approved for treatment of amyotrophic lateral sclerosis, was highly effective as a single dose by an intraperitoneal injection, causing a rise in BDNF localized in dentate granule neurons, the hilus, and the stratum radiatum of the CA3 region. Repeated, but not single, injections resulted in prolonged elevation of hippocampal BDNF and were associated with increased numbers of newly generated cells in the granule cell layer. This appeared due to promoted proliferation rather than survival of precursor cells, many of which differentiated into neurons. Intraventricular administration of BDNF-specific antibodies blocked such riluzole effects, suggesting that BDNF increase is necessary for the promotion of precursor proliferation. Our results suggest the basis for a new strategy for treatment of memory dysfunction.

  5. Micro- and nano-topography to enhance proliferation and sustain functional markers of donor-derived primary human corneal endothelial cells.

    PubMed

    Muhammad, Rizwan; Peh, Gary S L; Adnan, Khadijah; Law, Jaslyn B K; Mehta, Jodhbir S; Yim, Evelyn K F

    2015-06-01

    One of the most common indications for corneal transplantation is corneal endothelium dysfunction, which can lead to corneal blindness. Due to a worldwide donor cornea shortage, alternative treatments are needed, but the development of new treatment strategies relies on the successful in vitro culture of primary human corneal endothelial cells (HCECs) because transformed cell lines and animal-derived corneal endothelial cells are not desirable for therapeutic applications. Primary HCECs are non-proliferative in vivo and challenging to expand in vitro while maintaining their characteristic cell morphology and critical markers. Biochemical cues such as growth factors and small molecules have been investigated to enhance the expansion of HCECs with a limited increase in proliferation. In this study, patterned tissue culture polystyrene (TCPS) was shown to significantly enhance the expansion of HCECs. The proliferation of HCECs increased up to 2.9-fold, and the expression amount and localization of cell-cell tight junction protein Zona Occludens-1 (ZO-1) was significantly enhanced when grown on 1 μm TCPS pillars. 250 nm pillars induced an optimal hexagonal morphology of HCEC cells. Furthermore, we demonstrated that the topographical effect on tight-junction expression and cell morphology could be maintained throughout each passage, and was effectively 'remembered' by the cells. Higher amount of tight-junction protein expression was maintained at cell junctions when topographic cues were removed in the successive seeding. This topographic memory suggested topography-exposed/induced cells would maintain the enhanced functional markers, which would be useful in cell-therapy based approaches to enable the in situ endothelial cell monolayer formation upon delivery. The development of patterned TCPS culture platforms could significantly benefit those researching human corneal endothelial cell cultivation for cell therapy, and tissue engineering applications.

  6. Passive leg movement enhances interstitial VEGF protein, endothelial cell proliferation, and eNOS mRNA content in human skeletal muscle.

    PubMed

    Hellsten, Ylva; Rufener, Nora; Nielsen, Jens J; Høier, Birgitte; Krustrup, Peter; Bangsbo, Jens

    2008-03-01

    The present study used passive limb movement as an experimental model to study the effect of increased blood flow and passive stretch, without enhanced metabolic demand, in young healthy male subjects. The model used was 90 min of passive movement of the leg leading to a 2.8-fold increase (P < 0.05) in blood flow without a significant enhancement in oxygen uptake. Muscle interstitial fluid was sampled with microdialysis technique and analyzed for vascular endothelial growth factor (VEGF) protein and for the effect on endothelial cell proliferation. Biopsies obtained from the musculus vastus lateralis were analyzed for mRNA content of VEGF, endothelial nitric oxide synthase (eNOS), and matrix metalloproteinase-2 (MMP-2). The passive leg movement caused an increase (P < 0.05) in interstitial VEGF protein concentration above rest (73 +/- 21 vs. 344 +/- 83 pg/ml). Addition of muscle dialysate to cultured endothelial cells revealed that dialysate obtained during leg movement induced a 3.2-fold higher proliferation rate (P < 0.05) than dialysate obtained at rest. Passive movement also enhanced (P < 0.05) the eNOS mRNA level fourfold above resting levels. VEGF mRNA and MMP-2 mRNA levels were unaffected. The results show that a session of passive leg movement, elevating blood flow and causing passive stretch, augments the interstitial concentrations of VEGF, the proliferative effect of interstitial fluid, and eNOS mRNA content in muscle tissue. We propose that enhanced blood flow and passive stretch are positive physiological stimulators of factors associated with capillary growth in human muscle.

  7. Fibroblast growth factor-2 stimulates adipogenic differentiation of human adipose-derived stem cells

    SciTech Connect

    Kakudo, Natsuko . E-mail: kakudon@takii.kmu.ac.jp; Shimotsuma, Ayuko; Kusumoto, Kenji

    2007-07-27

    Adipose-derived stem cells (ASCs) have demonstrated a capacity for differentiating into a variety of lineages, including bone, cartilage, or fat, depending on the inducing stimuli and specific growth and factors. It is acknowledged that fibroblast growth factor-2 (FGF-2) promotes chondrogenic and inhibits osteogenic differentiation of ASCs, but thorough investigations of its effects on adipogenic differentiation are lacking. In this study, we demonstrate at the cellular and molecular levels the effect of FGF-2 on adipogenic differentiation of ASCs, as induced by an adipogenic hormonal cocktail consisting of 3-isobutyl-1-methylxanthine (IBMX), dexamethasone, insulin, and indomethacin. FGF-2 significantly enhances the adipogenic differentiation of human ASCs. Furthermore, in cultures receiving FGF-2 before adipogenic induction, mRNA expression of peroxisome proliferator-activated receptor {gamma}2 (PPAR{gamma}2), a key transcription factor in adipogenesis, was upregulated. The results of FGF-2 supplementation suggest the potential applications of FGF-2 and ASCs in adipose tissue regeneration.

  8. Enhancing the cellular anti-proliferation activity of pyridazinones as c-met inhibitors using docking analysis.

    PubMed

    Xing, Weiqiang; Ai, Jing; Jin, Shiyu; Shi, Zhangxing; Peng, Xia; Wang, Lang; Ji, Yinchun; Lu, Dong; Liu, Yang; Geng, Meiyu; Hu, Youhong

    2015-05-05

    A series of 2, 6-disubstituted pyridazinone derivatives were evaluated and optimized for their c-Met inhibitory activity in enzyme and cellular assay. An analysis of the SAR results arising from computer modeling analysis of members of the library led to the proposal that in order to obtain optimal inhibitory activity in cellular systems the lipophilic/hydrophilic properties of individual structural fragments in the inhibitors need to match those of corresponding binding pockets in the enzyme. Guided by this proposal, the quinoline-pyridazinone 8a, containing hydrophobic 6-indolyl pyridazinone and quinoline moieties along with a hydrophilic morpholine terminal group, was designed and synthesized. The results of studies with this substance showed that it is a selective c-Met inhibitor with both a high enzyme inhibition IC50 value of 4.2 nM and a high EBC-1 cell proliferation inhibition IC50 value of 17 nM.

  9. Collagen-containing scaffolds enhance attachment and proliferation of non-cultured bone marrow multipotential stromal cells.

    PubMed

    El-Jawhari, Jehan J; Sanjurjo-Rodríguez, Clara; Jones, Elena; Giannoudis, Peter V

    2016-04-01

    Large bone defects are ideally treated with autografts, which have many limitations. Therefore, osteoconductive scaffolds loaded with autologous bone marrow (BM) aspirate are increasingly used as alternatives. The purpose of this study was to compare the growth of multipotential stromal cells (MSCs) from unprocessed BM on a collagen-containing bovine bone scaffold (Orthoss(®) Collagen) with a non-collagen-containing bovine bone scaffold, Orthoss(®) . Another collagen-containing synthetic scaffold, Vitoss(®) was included in the comparison. Colonization of scaffolds by BM MSCs (n = 23 donors) was evaluated using microscopy, colony forming unit-fibroblast assay and flow-cytometry. The number of BM MSCs initially attached to Orthoss(®) Collagen and Vitoss(®) was similar but greater than Orthoss(®) (p = 0.001 and p = 0.041, respectively). Furthermore, the number of MSCs released from Orthoss(®) Collagen and Vitoss(®) after 2-week culture was also higher compared to Orthoss(®) (p = 0.010 and p = 0.023, respectively). Interestingly, collagen-containing scaffolds accommodated larger numbers of lymphocytic and myelomonocytic cells. Additionally, the proliferation of culture-expanded MSCs on Orthoss(®) collagen and Vitoss(®) was greater compared to Orthoss(®) (p = 0.047 and p = 0.004, respectively). Collectively, collagen-containing scaffolds were superior in supporting the attachment and proliferation of MSCs when they were loaded with unprocessed BM aspirates. This highlights the benefit of collagen incorporation into bone scaffolds for use with autologous bone marrow aspirates as autograft substitutes.

  10. Novel degradable co-polymers of polypyrrole support cell proliferation and enhance neurite out-growth with electrical stimulation.

    PubMed

    Durgam, Hymavathi; Sapp, Shawn; Deister, Curt; Khaing, Zin; Chang, Emily; Luebben, Silvia; Schmidt, Christine E

    2010-01-01

    Synthetic polymers such as polypyrrole (PPy) are gaining significance in neural studies because of their conductive properties. We evaluated two novel biodegradable block co-polymers of PPy with poly(epsilon-caprolactone) (PCL) and poly(ethyl cyanoacrylate) (PECA) for nerve regeneration applications. PPy-PCL and PPy-PECA co-polymers can be processed from solvent-based colloidal dispersions and have essentially the same or greater conductivity (32 S/cm for PPy-PCL, 19 S/cm for PPy-PECA) compared to the PPy homo-polymer (22 S/cm). The PPy portions of the co-polymers permit electrical stimulation whereas the PCL or PECA blocks enable degradation by hydrolysis. For in vitro tests, films were prepared on polycarbonate sheets by air brushing layers of dispersions and pressing the films. We characterized the films for hydrolytic degradation, electrical conductivity, cell proliferation and neurite extension. The co-polymers were sufficient to carry out electrical stimulation of cells without the requirement of a metallic conductor underneath the co-polymer film. In vitro electrical stimulation of PPy-PCL significantly increased the number of PC12 cells bearing neurites compared to unstimulated PPy-PCL. For in vivo experiments, the PPy co-polymers were coated onto the inner walls of nerve guidance channels (NGCs) made of the commercially available non-conducting biodegradable polymer poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHB-HV). The NGCs were implanted in a 10 mm defect made in the sciatic nerve of rats, and harvested after 8 weeks. Histological staining showed axonal growth. The studies indicated that these new conducting degradable biomaterials have good biocompatibility and support proliferation and growth of PC12 cells in vitro (with and without electrical stimulation) and neurons in vivo (without electrical stimulation).

  11. Dioscorea Phytocompounds Enhance Murine Splenocyte Proliferation Ex Vivo and Improve Regeneration of Bone Marrow Cells In Vivo

    PubMed Central

    Su, Pei-Fen; Li, Chin-Jin; Hsu, Chih-Chien; Benson, Spencer; Wang, Sheng-Yang; Aravindaram, Kandan; Chan, Sunney I.; Wu, Shih-Hsiung; Yang, Feng-Ling; Huang, Wen-Ching; Shyur, Lie-Fen; Yang, Ning-Sun

    2011-01-01

    Specific cytokines have been tested clinically for immunotherapy of cancers; however, cytotoxicity has often impaired their usefulness. Consequently, alternative approaches are increasingly desirable. Dioscorea spp. tuber is a widely used traditional Chinese medicinal herb claimed to confer immunostimulatory activity. In this study, we evaluated Dioscorea as an adjuvant therapy for use alongside chemotherapy for cancer. Phytocompounds from Dioscorea tubers were ethanol fractioned and used for ex vivo splenocyte proliferation assay or in vivo force-feeding of mice pre-treated with the chemotherapy agent 5-fluorouracil. Co-treatment with a 50–75% ethanol-partitioned fraction of the tuber extract of D. batatas (DsCE-II) and interleukin (IL)-2 resulted in a significantly higher rate of murine splenocyte cell proliferation ex vivo than treatment with DsCE-II or IL-2 alone. This DsCE-II fraction, which contains a polysaccharide with a high proportion of β-1,4-linkage mannose (≥64%), also promoted the regeneration of specific progenitor cell populations in damaged bone marrow tissues of 5-fluorouracil-treated mice. Colony-forming unit (CFU) analyses demonstrated that the population of CFU-GM cells, but not CFU-GEMM or BFU-E cells, preferentially recovered to ~67% in the bone marrow of immune-suppressed mice fed with DsCE-II. DsCE-II efficacy level was ~85% of that obtained by subcutaneous administration of recombinant G-CSF proteins (5 μg kg−1) in mice tested in parallel. This study suggests that the DsCE-II fraction of D. batatas extract may be considered for further development as a dietary supplement for use alongside chemotherapy during cancer treatment. PMID:21799689

  12. Collagen‐containing scaffolds enhance attachment and proliferation of non‐cultured bone marrow multipotential stromal cells

    PubMed Central

    El‐Jawhari, Jehan J.; Sanjurjo‐Rodríguez, Clara; Jones, Elena

    2015-01-01

    ABSTRACT Large bone defects are ideally treated with autografts, which have many limitations. Therefore, osteoconductive scaffolds loaded with autologous bone marrow (BM) aspirate are increasingly used as alternatives. The purpose of this study was to compare the growth of multipotential stromal cells (MSCs) from unprocessed BM on a collagen‐containing bovine bone scaffold (Orthoss® Collagen) with a non‐collagen‐containing bovine bone scaffold, Orthoss®. Another collagen‐containing synthetic scaffold, Vitoss® was included in the comparison. Colonization of scaffolds by BM MSCs (n = 23 donors) was evaluated using microscopy, colony forming unit‐fibroblast assay and flow‐cytometry. The number of BM MSCs initially attached to Orthoss® Collagen and Vitoss® was similar but greater than Orthoss® (p = 0.001 and p = 0.041, respectively). Furthermore, the number of MSCs released from Orthoss® Collagen and Vitoss® after 2‐week culture was also higher compared to Orthoss® (p = 0.010 and p = 0.023, respectively). Interestingly, collagen‐containing scaffolds accommodated larger numbers of lymphocytic and myelomonocytic cells. Additionally, the proliferation of culture‐expanded MSCs on Orthoss® collagen and Vitoss® was greater compared to Orthoss® (p = 0.047 and p = 0.004, respectively). Collectively, collagen‐containing scaffolds were superior in supporting the attachment and proliferation of MSCs when they were loaded with unprocessed BM aspirates. This highlights the benefit of collagen incorporation into bone scaffolds for use with autologous bone marrow aspirates as autograft substitutes. © 2015 The Authors. Journal of Orthopaedic Research Published by Wiley Periodicals, Inc. on behalf of Orthopaedic Research Society. J Orthop Res 34:597–606, 2016. PMID:26466765

  13. An amino acid-based oral rehydration solution (AA-ORS) enhanced intestinal epithelial proliferation in mice exposed to radiation

    PubMed Central

    Yin, Liangjie; Gupta, Reshu; Vaught, Lauren; Grosche, Astrid; Okunieff, Paul; Vidyasagar, Sadasivan

    2016-01-01

    Destruction of clonogenic cells in the crypt following irradiation are thought to cause altered gastrointestinal function. Previously, we found that an amino acid-based oral rehydration solution (AA-ORS) improved gastrointestinal function in irradiated mice. However, the exact mechanisms were unknown. Electrophysiology, immunohistochemistry, qPCR, and Western blot analysis were used to determine that AA-ORS increased proliferation, maturation, and differentiation and improved electrolyte and nutrient absorption in irradiated mice. A single-hit, multi-target crypt survival curve showed a significant increase in crypt progenitors in irradiated mice treated with AA-ORS for six days (8.8 ± 0.4) compared to the saline-treated group (6.1 ± 0.3; P < 0.001) without a change in D0 (4.8 ± 0.1 Gy). The Dq values increased from 8.8 ± 0.4 Gy to 10.5 ± 0.5 Gy with AA-ORS treatment (P < 0.01), indicating an increased radiation tolerance of 1.7 Gy. We also found that AA-ORS treatment (1) increased Lgr5+, without altering Bmi1 positive cells; (2) increased levels of proliferation markers (Ki-67, p-Erk, p-Akt and PCNA); (3) decreased apoptosis markers, such as cleaved caspase-3 and Bcl-2; and (4) increased expression and protein levels of NHE3 and SGLT1 in the brush border membrane. This study shows that AA-ORS increased villus height and improved electrolyte and nutrient absorption. PMID:27876791

  14. Inhibition of Enhancer of Zeste Homolog 2 (EZH2) expression is associated with decreased tumor cell proliferation, migration and invasion in endometrial cancer cell lines

    PubMed Central

    Eskander, Ramez N.; Ji, Tao; Huynh, Be; Wardeh, Rooba; Randall, Leslie M; Hoang, Bang

    2013-01-01

    Objective To investigate the impact of Enhancer of Zeste Homolog 2 (EZH2) expression on endometrial cancer cell line behavior. Methods/materials EZH2 expression levels were compared between the non-malignant endometrial cell line T-HESC, and 3 endometrial cancer cell lines, ECC-1, RL95-2 and HEC1-A. Stable EZH2 knockdown cell lines were created and the impact on cellular proliferation, migration and invasion were determined. Fluorescent activated cell sorting was used to examine effects of EZH2 silencing on cell cycle progression. EZH2 expression in endometrial cancer tissue specimens was examined using immunohistochemistry. Comparison of differences between control and shEZH2 cell lines was performed using student's t test and Fischer's exact test. Results EZH2 protein expression was increased in all 3 cancer cell lines, and human endometrial cancer tissue specimens relative to control. RNA interference of EZH2 expression in ECC-1, RL95-2, and HEC1-A significantly decreased cell proliferation, migration and invasion. Down regulation of EZH2 expression resulted in a significant increase in the proportion of cells arrested in G2/M. RNA interference of EZH2 expression was associated with an increase in the expression of Wnt pathway inhibitors sFRP1 and DKK3, and a concomitant decrease in β-catenin. EZH2 expression in human tissue samples was significantly associated with increased stage, grade, depth of invasion and nodal metastasis. Conclusions EZH2 expression is associated with tumor cell proliferation, migration and invasion in 3 endometrial cancer cell lines, as well as increased stage, grade, depth of invasion and nodal metastasis in human cancer tissue specimens. Further investigation into this potential therapeutic target is warranted. PMID:23792601

  15. Increased levels of palmitoylethanolamide and other bioactive lipid mediators and enhanced local mast cell proliferation in canine atopic dermatitis

    PubMed Central

    2014-01-01

    Background Despite the precise pathogenesis of atopic dermatitis (AD) is unknown, an immune dysregulation that causes Th2-predominant inflammation and an intrinsic defect in skin barrier function are currently the two major hypotheses, according to the so-called outside-inside-outside model. Mast cells (MCs) are involved in AD both by releasing Th2 polarizing cytokines and generating pruritus symptoms through release of histamine and tryptase. A link between MCs and skin barrier defects was recently uncovered, with histamine being found to profoundly contribute to the skin barrier defects. Palmitoylethanolamide and related lipid mediators are endogenous bioactive compounds, considered to play a protective homeostatic role in many tissues: evidence collected so far shows that the anti-inflammatory effect of palmitoylethanolamide depends on the down-modulation of MC degranulation. Based on this background, the purpose of the present study was twofold: (a) to determine if the endogenous levels of palmitoylethanolamide and other bioactive lipid mediators are changed in the skin of AD dogs compared to healthy animals; (b) to examine if MC number is increased in the skin of AD dogs and, if so, whether it depends on MC in-situ proliferation. Results The amount of lipid extract expressed as percent of biopsy tissue weight was significantly reduced in AD skin while the levels of all analyzed bioactive lipid mediators were significantly elevated, with palmitoylethanolamide showing the highest increase. In dogs with AD, the number of MCs was significantly increased in both the subepidermal and the perifollicular compartments and their granule content was significantly decreased in the latter. Also, in situ proliferation of MCs was documented. Conclusions The levels of palmitoylethanolamide and other bioactive lipid mediators were shown to increase in AD skin compared to healthy samples, leading to the hypothesis that they may be part of the body’s innate mechanisms to

  16. The glucagon-like peptide 1 receptor agonist enhances intrinsic peroxisome proliferator-activated receptor γ activity in endothelial cells

    SciTech Connect

    Onuma, Hirohisa; Inukai, Kouichi Kitahara, Atsuko; Moriya, Rie; Nishida, Susumu; Tanaka, Toshiaki; Katsuta, Hidenori; Takahashi, Kazuto; Sumitani, Yoshikazu; Hosaka, Toshio; Ishida, Hitoshi

    2014-08-22

    Highlights: • PPARγ activation was involved in the GLP-1-mediated anti-inflammatory action. • Exendin-4 enhanced endogenous PPARγ transcriptional activity in HUVECs. • H89, a PKA inhibitor, abolished GLP-1-induced PPARγ enhancement. • The anti-inflammatory effects of GLP-1 may be explained by PPARγ activation. - Abstract: Recent studies have suggested glucagon-like peptide-1 (GLP-1) signaling to exert anti-inflammatory effects on endothelial cells, although the precise underlying mechanism remains to be elucidated. In the present study, we investigated whether PPARγ activation is involved in the GLP-1-mediated anti-inflammatory action on endothelial cells. When we treated HUVEC cells with 0.2 ng/ml exendin-4, a GLP-1 receptor agonist, endogenous PPARγ transcriptional activity was significantly elevated, by approximately 20%, as compared with control cells. The maximum PPARγ activity enhancing effect of exendin-4 was observed 12 h after the initiation of incubation with exendin-4. As H89, a PKA inhibitor, abolished GLP-1-induced PPARγ enhancement, the signaling downstream from GLP-1 cross-talk must have been involved in PPARγ activation. In conclusion, our results suggest that GLP-1 has the potential to induce PPARγ activity, partially explaining the anti-inflammatory effects of GLP-1 on endothelial cells. Cross-talk between GLP-1 signaling and PPARγ activation would have major impacts on treatments for patients at high risk for cardiovascular disease.

  17. Enhancing anticoagulation and endothelial cell proliferation of titanium surface by sequential immobilization of poly(ethylene glycol) and collagen

    NASA Astrophysics Data System (ADS)

    Pan, Chang-Jiang; Hou, Yan-Hua; Ding, Hong-Yan; Dong, Yun-Xiao

    2013-12-01

    In the present study, poly(ethylene glycol) (PEG) and collagen I were sequentially immobilized on the titanium surface to simultaneously improve the anticoagulation and endothelial cell proliferation. Attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) and X-ray photoelectron spectroscopy analysis confirmed that PEG and collagen I were successfully immobilized on the titanium surface. Water contact angle results suggested the excellent hydrophilic surface after the immobilization. The anticoagulation experiments demonstrated that the immobilized PEG and collagen I on the titanium surface could not only obviously prevent platelet adhesion and aggregation but also prolong activated partial thromboplastin time (APTT), leading to the improved blood compatibility. Furthermore, immobilization of collagen to the end of PEG chain did not abate the anticoagulation. As compared to those on the pristine and PEG-modified titanium surfaces, endothelial cells exhibited improved proliferative profiles on the surface modified by the sequential immobilization of PEG and collagen in terms of CCK-8 assay, implying that the modified titanium may promote endothelialization without abating the blood compatibility. Our method may be used to modify the surface of blood-contacting biomaterials such as titanium to promote endothelialization and improve the anticoagulation, it may be helpful for development of the biomedical devices such as coronary stents, where endothelializaton and excellent anticoagulation are required.

  18. Targeting histone deacetylase 6 mediates a dual anti-melanoma effect: Enhanced antitumor immunity and impaired cell proliferation

    PubMed Central

    Perez-Villaroel, P.; Lee, C.; Cheng, F.; Knox, T.; Woods, D.M.; Barrios, K.; Powers, J.; Sahakian, E.; Wang, H.W.; Canales, J.; Marante, D.; Smalley, K.S.M.; Bergman, J.; Seto, E.; Kozikowski, A.; Pinilla-Ibarz, J.; Sarnaik, A.; Celis, E.; Weber, J.; Sotomayor, E.M.; Villagra, A.

    2015-01-01

    The median survival for metastatic melanoma is in the realm of 8–16 months and there are few therapies that offer significant improvement in overall survival. One of the recent advances in cancer treatment focuses on epigenetic modifiers to alter the survivability and immunogenicity of cancer cells. Our group and others have previously demonstrated that pan-HDAC inhibitors induce apoptosis, cell cycle arrest and changes in the immunogenicity of melanoma cells. Here we interrogated specific HDACs which may be responsible for this effect. We found that both genetic abrogation and pharmacologic inhibition of HDAC6 decreases in vitro proliferation and induces G1 arrest of melanoma cell lines without inducing apoptosis. Moreover, targeting this molecule led to an important upregulation in the expression of tumor associated antigens and MHC class I, suggesting a potential improvement in the immunogenicity of these cells. Of note, this anti-melanoma activity was operative regardless of mutational status of the cells. These effects translated into a pronounced delay of in vivo melanoma tumor growth which was, at least in part, dependent on intact immunity as evidenced by the restoration of tumor growth after CD4+ and CD8+ depletion. Given our findings, we provide the initial rationale for the further development of selective HDAC6 inhibitors as potential therapeutic anti-melanoma agents. PMID:25957812

  19. Light attenuates lipid accumulation while enhancing cell proliferation and starch synthesis in the glucose-fed oleaginous microalga Chlorella zofingiensis

    PubMed Central

    Chen, Tianpeng; Liu, Jin; Guo, Bingbing; Ma, Xiaonian; Sun, Peipei; Liu, Bin; Chen, Feng

    2015-01-01

    The objective of this study was to investigate the effect of light on lipid and starch accumulation in the oleaginous green algae Chlorella zofingiensis supplemented with glucose. C. zofingiensis, when fed with 30 g/L glucose, synthesized lipids up to 0.531 g/g dry weight; while in the presence of light, the lipid content dropped down to 0.352 g/g dry weight. Lipid yield on glucose was 0.184 g/g glucose, 14% higher than that cultured with light. The light-mediated lipid reduction was accompanied by the down-regulation of fatty acid biosynthetic genes at the transcriptional level. Furthermore, light promoted cell proliferation, starch accumulation, and the starch yield based on glucose. Taken together, light may attenuate lipid accumulation, possibly through the inhibition of lipid biosynthetic pathway, leading to more carbon flux from glucose to starch. This study reveals the dual effects of light on the sugar-fed C. zofingiensis and provides valuable insights into the possible optimization of algal biomass and lipid production by manipulation of culture conditions. PMID:26442783

  20. Intermittent pneumatic compression enhances neurovascular ingrowth and tissue proliferation during connective tissue healing: a study in the rat.

    PubMed

    Dahl, Johan; Li, Jian; Bring, Daniel K-I; Renström, Per; Ackermann, Paul W

    2007-09-01

    Intermittent pneumatic compression (IPC) is a treatment method to decrease venous stasis and stimulate blood flow. Recently, it was hypothesized that IPC may exert positive effects on tissue healing, a process highly dependent upon adequate circulation. In this study, we investigated the effects of daily 1-h IPC treatment during 2 and 4 weeks post-rat Achilles tendon rupture. The tendons were subjectively and semiquantitatively analyzed for collagen organization, fibroblast density, angiogenesis, and the occurrence of sensory neuropeptides, substance P (SP) and calcitonine gene related peptide (CGRP), as well as for a nerve regeneration marker, growth associated protein 43 (GAP-43). After 2 weeks of treatment, fibroblast density increased by 53% (p = 0.0004), vessel density by 64% (p = 0.022), and the occurrence of SP by 110% (p = 0.047) and CGRP by 47% (p = 0.0163) compared to untreated controls. Following 4 weeks of treatment, both the occurrence of sensory neuropeptides and the vessel density remained significantly higher (p < 0.05), whereas fibroblast density returned to normal. However, at 4 weeks the treated tendons displayed a higher degree of organized parallel collagen fibers, a sign of increased maturation. Daily IPC treatment improves neurovascular ingrowth and fibroblast proliferation in the healing tendon and may accelerate the repair process.

  1. Light attenuates lipid accumulation while enhancing cell proliferation and starch synthesis in the glucose-fed oleaginous microalga Chlorella zofingiensis.

    PubMed

    Chen, Tianpeng; Liu, Jin; Guo, Bingbing; Ma, Xiaonian; Sun, Peipei; Liu, Bin; Chen, Feng

    2015-10-07

    The objective of this study was to investigate the effect of light on lipid and starch accumulation in the oleaginous green algae Chlorella zofingiensis supplemented with glucose. C. zofingiensis, when fed with 30 g/L glucose, synthesized lipids up to 0.531 g/g dry weight; while in the presence of light, the lipid content dropped down to 0.352 g/g dry weight. Lipid yield on glucose was 0.184 g/g glucose, 14% higher than that cultured with light. The light-mediated lipid reduction was accompanied by the down-regulation of fatty acid biosynthetic genes at the transcriptional level. Furthermore, light promoted cell proliferation, starch accumulation, and the starch yield based on glucose. Taken together, light may attenuate lipid accumulation, possibly through the inhibition of lipid biosynthetic pathway, leading to more carbon flux from glucose to starch. This study reveals the dual effects of light on the sugar-fed C. zofingiensis and provides valuable insights into the possible optimization of algal biomass and lipid production by manipulation of culture conditions.

  2. IGF-1R and ErbB3/HER3 contribute to enhanced proliferation and carcinogenesis in trastuzumab-resistant ovarian cancer model

    SciTech Connect

    Jia, Yanhan; Zhang, Yan; Qiao, Chunxia; Liu, Guijun; Zhao, Qing; Zhou, Tingting; Chen, Guojiang; Li, Yali; Feng, Jiannan; Li, Yan; Zhang, Qiuping; Peng, Hui

    2013-07-12

    Highlights: •We established trastuzumab-resistant cell line SKOV3/T. •SKOV3/T enhances proliferation and in vivo carcinogenesis. •IGF-1R and HER3 genes were up-regulated in SKOV3/T based on microarray analysis. •Targeting IGF-1R and/or HER3 inhibited the proliferation of SKOV3/T. •Therapies targeting IGF-1R and HER3 might be effective in ovarian cancer. -- Abstract: Trastuzumab (Herceptin®) has demonstrated clinical potential in several types of HER2-overexpressing human cancers. However, primary and acquired resistance occurs in many HER2-positive patients with regimens. To investigate the possible mechanism of acquired therapeutic resistance to trastuzumab, we have developed a preclinical model of human ovarian cancer cells, SKOV3/T, with the distinctive feature of stronger carcinogenesis. The differences in gene expression between parental and the resistant cells were explored by microarray analysis, of which IGF-1R and HER3 were detected to be key molecules in action. Their correctness was validated by follow-up experiments of RT-PCR, shRNA-mediated knockdown, downstream signal activation, cell cycle distribution and survival. These results suggest that IGF-1R and HER3 differentially regulate trastuzumab resistance and could be promising targets for trastuzumab therapy in ovarian cancer.

  3. Gemcitabine Conjugated Chitosan and Double Antibodies (Abc-GC-Gemcitabine Nanoparticles) Enhanced Cytoplasmic Uptake of Gemcitabine and Inhibit Proliferation and Metastasis In Human SW1990 Pancreatic Cancer Cells

    PubMed Central

    Xiao, Jun; Yu, Haibo

    2017-01-01

    Background Pancreatic cancer is considered a chemoresistant neoplasm with extremely dismal prognosis and gemcitabine treatment is associated with many side effects and poor overall survival. The study aimed at developing a new nanobioconjugate, which specifically delivered gemcitabine and anti-EGFR antibody into pancreatic cancer cells. Material/Methods The novel nanodrug is based on chitosan platform, which is non-toxic, biocompatibility and biodegradable. We measured the effects of proliferation and metastasis on SW1990 by CCK-8 assay, colony formation assay, wound healing assay and Transwell assay. The expression of related proteins were evaluated by Western blot. Results We synthesized Abc-GC-gemcitabine nanoparticles successfully with the encapsulation rate of nanobioconjugates was 91.63% and the drug loadings was 9.97%. Both GC-gemcitabine microspheres solution (GC group) and Abc-GC-gemcitabine microspheres solution (Abc group) inhibited cells proliferation, colony formation, migration and invasion in SW1990 cells dramatically. Moreover, Abc-GC-gemcitabine microspheres expressed more significant inhibited action than GC-gemcitabine microspheres efficiently Conclusions Our data suggested that Abc-GC-gemcitabine nanoparticles could have promising potential in treating metastasized and chemoresistant pancreatic cancer by enhancing the drug efficacy and minimizing off target effects. PMID:28366930

  4. Gemcitabine Conjugated Chitosan and Double Antibodies (Abc-GC-Gemcitabine Nanoparticles) Enhanced Cytoplasmic Uptake of Gemcitabine and Inhibit Proliferation and Metastasis In Human SW1990 Pancreatic Cancer Cells.

    PubMed

    Xiao, Jun; Yu, Haibo

    2017-04-03

    BACKGROUND Pancreatic cancer is considered a chemoresistant neoplasm with extremely dismal prognosis and gemcitabine treatment is associated with many side effects and poor overall survival. The study aimed at developing a new nanobioconjugate, which specifically delivered gemcitabine and anti-EGFR antibody into pancreatic cancer cells. MATERIAL AND METHODS The novel nanodrug is based on chitosan platform, which is non-toxic, biocompatibility and biodegradable. We measured the effects of proliferation and metastasis on SW1990 by CCK-8 assay, colony formation assay, wound healing assay and Transwell assay. The expression of related proteins were evaluated by Western blot. RESULTS We synthesized Abc-GC-gemcitabine nanoparticles successfully with the encapsulation rate of nanobioconjugates was 91.63% and the drug loadings was 9.97%. Both GC-gemcitabine microspheres solution (GC group) and Abc-GC-gemcitabine microspheres solution (Abc group) inhibited cells proliferation, colony formation, migration and invasion in SW1990 cells dramatically. Moreover, Abc-GC-gemcitabine microspheres expressed more significant inhibited action than GC-gemcitabine microspheres efficiently CONCLUSIONS Our data suggested that Abc-GC-gemcitabine nanoparticles could have promising potential in treating metastasized and chemoresistant pancreatic cancer by enhancing the drug efficacy and minimizing off target effects.

  5. The transcription factor protein Sox11 enhances early osteoblast differentiation by facilitating proliferation and the survival of mesenchymal and osteoblast progenitors.

    PubMed

    Gadi, Jogeswar; Jung, Seung-Hyun; Lee, Min-Jung; Jami, Ajita; Ruthala, Kalyani; Kim, Kyoung-Min; Cho, Nam-Hoon; Jung, Han-Sung; Kim, Cheol-Hee; Lim, Sung-Kil

    2013-08-30

    Sox11 deletion mice are known to exhibit developmental defects of craniofacial skeletal malformations, asplenia, and hypoplasia of the lung, stomach, and pancreas. Despite the importance of Sox11 in the developing skeleton, the role of Sox11 in osteogenesis has not been studied yet. In this study, we identified that Sox11 is an important transcription factor for regulating the proliferation and survival of osteoblast precursor cells as well as the self-renewal potency of mesenchymal progenitor cells via up-regulation of Tead2. Furthermore, Sox11 also plays an important role in the segregation of functional osteoblast lineage progenitors from osteochondrogenic progenitors. Facilitation of osteoblast differentiation from mesenchymal cells was achieved by enhanced expression of the osteoblast lineage specific transcription factors Runx2 and Osterix. Morpholino-targeted disruption of Sox11 in zebrafish impaired organogenesis, including the bones, which were under mineralized. These results indicated that Sox11 plays a crucial role in the proliferation and survival of mesenchymal and osteoblast precursors by Tead2, and osteogenic differentiation by regulating Runx2 and Osterix.

  6. Polypodium leucotomos decreases UV-induced epidermal cell proliferation and enhances p53 expression and plasma antioxidant capacity in hairless mice.

    PubMed

    Rodríguez-Yanes, Esperanza; Juarranz, Ángeles; Cuevas, Jesús; Gonzalez, Salvador; Mallol, Jordi

    2012-08-01

    A single dose of ultraviolet radiation (UVR) induces significant changes in blood and skin of hairless mice. Oral administration of a hydrophilic extract of the fern Polypodium leucotomos (PL, 300 mg/kg during 5 days before UVR and for two additional days after irradiation) modulates some of the effects of UVR. Most significantly, PL administration reduced the number of proliferating cells by 13%, increased the number of p53(+) cells by 63%, enhanced the antioxidant plasma capacity (ORAC) by 30% and reinforced the network of dermal elastic fibres. Western blot analysis of skin antioxidant-related enzymes failed to demonstrate significant changes caused by PL. Thus, the beneficial effect of PL likely owes to its antioxidant and anti-ROS properties rather than its modulation of the expression of endogenous antioxidant systems. These data provide mechanistic clues for its efficacy as a systemic photoprotective agent with antioxidant and anti-photo-ageing properties.

  7. Indirect coating of RGD peptides using a poly-L-lysine spacer enhances jaw periosteal cell adhesion, proliferation, and differentiation into osteogenic tissue.

    PubMed

    Ardjomandi, N; Klein, C; Kohler, K; Maurer, A; Kalbacher, H; Niederländer, J; Reinert, S; Alexander, D

    2012-08-01

    The aim of our study was to generate a biofunctionalized, three-dimensional (3D) biomaterial to enhance jaw periosteal cell (JPC) adhesion and differentiation into osteogenic tissue. Therefore, open-cell polylactic acid (OPLA) scaffolds were coated covalently with different RGD peptides (a conserved recognition sequence of the most ECM proteins--arginine-glycine-asparagine) and different coating variants. The linear and cyclic RGD peptides were either applied directly or indirectly via a poly-L-lysine (PLL) spacer. JPCs were analyzed on coated constructs in 2D and 3D cultures and showed enhanced rates for indirectly coated scaffolds using the PLL spacer. By gene expression, we detected significantly increased levels of osteogenic marker genes, such as alkaline phosphatase, RUNX2, and AMELY in JPCs seeded onto PLL/linear RGD constructs compared to the otherwise-coated constructs. An analysis of the JPC mineralization capacity revealed the highest amounts of calcium-phosphate precipitates in cells growing within the PLL/linear scaffolds. Additionally, the JPC adhesion behavior on OPLA scaffolds seems to be mediated by ITGB3, ITGB1, and ITGAV, as shown by blocking assays. We concluded that coating of OPLA constructs with linear RGD peptides via PLL represents a suitable approach for functionalizing the polymer surface and enhancing adhesion, proliferation, and mineralization of JPCs.

  8. Sensitivity to methylmercury toxicity is enhanced in oxoguanine glycosylase 1 knockout murine embryonic fibroblasts and is dependent on cellular proliferation capacity

    SciTech Connect

    Ondovcik, Stephanie L.; Tamblyn, Laura; McPherson, John Peter; Wells, Peter G.

    2013-07-01

    Methylmercury (MeHg) is a persistent environmental contaminant with potent neurotoxic action for which the underlying molecular mechanisms remain to be conclusively delineated. Our objectives herein were twofold: first, to corroborate our previous findings of an increased sensitivity of spontaneously-immortalized oxoguanine glycosylase 1-null (Ogg1{sup −/−}) murine embryonic fibroblasts (MEFs) to MeHg through generation of Simian virus 40 (SV40) large T antigen-immortalized wild-type and Ogg1{sup −/−} MEFs; and second, to determine whether MeHg toxicity is proliferation-dependent. As with the spontaneously-immortalized cells used previously, the SV40 large T antigen-immortalized cells exhibited similar tendencies to undergo MeHg-initiated cell cycle arrest, with increased sensitivity in the Ogg1{sup −/−} MEFs as measured by clonogenic survival and DNA damage. Compared to exponentially growing cells, those seeded at a higher density exhibited compromised proliferation, which proved protective against MeHg-mediated cell cycle arrest and induction of DNA double strand breaks (DSBs), measured by phosphorylation of the core histone H2A variant (H2AX) on serine 139 (γH2AX), and by its functional confirmation by micronucleus assessment. This enhanced sensitivity of Ogg1{sup −/−} MEFs to MeHg toxicity using discrete SV40 immortalization corroborates our previous studies, and suggests a novel role for OGG1 in minimizing MeHg-initiated DNA lesions that trigger replication-associated DSBs. Furthermore, proliferative capacity may determine MeHg toxicity in vivo and in utero. Accordingly, variations in cellular proliferative capacity and interindividual variability in repair activity may modulate the risk of toxicological consequences following MeHg exposure. - Highlights: • SV40 large T antigen-immortalized Ogg1{sup −/−} cells are more sensitive to MeHg. • Sensitivity to MeHg is dependent on cellular proliferation capacity. • OGG1 maintains genomic

  9. Enhanced effects by 4-phenylbutyrate in combination with RTK inhibitors on proliferation in brain tumor cell models

    SciTech Connect

    Marino, Ana-Maria; Sofiadis, Anastasios; Baryawno, Ninib; Johnsen, John Inge; Larsson, Catharina; Vukojevic, Vladana; Ekstroem, Tomas J.

    2011-07-22

    Highlights: {yields} The histone deacetylase inhibitor 4-phenylbutyrate substantially enhance efficacy of the receptor tyrosine kinase inhibitors gefitinib or vandetanib in glioma and medulloblastoma cell lines. {yields} Cell death increases and clonogenic survival is reduced in the combination treatments, over mono-therapy. {yields} Combination treatments with these drugs may improve clinical outcome for cancer therapy. -- Abstract: We have investigated in vitro effects of anticancer therapy with the histone deacetylase inhibitor (HDACi) 4-phenylbutyrate (4-PB) combined with receptor tyrosine kinase inhibitors (RTKi) gefitinib or vandetanib on the survival of glioblastoma (U343MGa) and medulloblastoma (D324Med) cells. In comparison with individual effects of these drugs, combined treatment with gefitinib/4-PB or vandetanib/4-PB resulted in enhanced cell killing and reduced clonogenic survival in both cell lines. Our results suggest that combined treatment using HDACi and RTKi may beneficially affect the outcome of cancer therapy.

  10. MicroRNA-148b enhances proliferation and apoptosis in human renal cancer cells via directly targeting MAP3K9.

    PubMed

    Nie, Fang; Liu, Tianming; Zhong, Liang; Yang, Xianggui; Liu, Yunhong; Xia, Hongwei; Liu, Xiaoqiang; Wang, Xiaoyan; Liu, Zhicheng; Zhou, Li; Mao, Zhaomin; Zhou, Qin; Chen, Tingmei

    2016-01-01

    Increasing evidence revealed that miRNAs, the vital regulators of gene expression, are involved in various cellular processes, including cell growth, differentiation, apoptosis and progression. In addition, miRNAs act as oncogenes and/or tumor suppressors. The present study aimed to verify the potential roles of miR148b in human renal cancer cells. miR‑148b was found to be downregulated in human renal cancel tissues and human renal cancer cell lines. Functional studies demonstrated that plasmid‑mediated overexpression of miR‑148b promoted cell proliferation, increased the S‑phase population of the cell cycle and enhanced apoptosis in the 786‑O and OS‑RC‑2 renal cancer cell lines, while it did not appear to affect the total number of viable cells according to a Cell Counting Kit‑8 assay. Subsequently, a luciferase reporter assay verified that miR148b directly targeted mitogen‑activated protein kinase (MAPK) kinase kinase 9 (MAP3K9), an upstream activator of MAPK kinase/c‑Jun N‑terminal kinase (JNK) signaling, suppressing the protein but not the mRNA levels. Furthermore, western blot analysis indicated that overexpression of miR148b in renal cancer cells inhibited MAPK/JNK signaling by decreasing the expression of phosphorylated (p)JNK. In addition, overexpression of MAP3K9 and pJNK was detected in clinical renal cell carcinoma specimens compared with that in their normal adjacent tissues. The present study therefore suggested that miR‑148b exerts an oncogenic function by enhancing the proliferation and apoptosis of renal cancer cells by inhibiting the MAPK/JNK pathway.

  11. Enhanced sensitivity to IGF-II signaling links loss of imprinting of IGF2 to increased cell proliferation and tumor risk.

    PubMed

    Kaneda, Atsushi; Wang, Chiaochun J; Cheong, Raymond; Timp, Winston; Onyango, Patrick; Wen, Bo; Iacobuzio-Donahue, Christine A; Ohlsson, Rolf; Andraos, Rita; Pearson, Mark A; Sharov, Alexei A; Longo, Dan L; Ko, Minoru S H; Levchenko, Andre; Feinberg, Andrew P

    2007-12-26

    Loss of imprinting (LOI) of the insulin-like growth factor-II gene (IGF2), leading to abnormal activation of the normally silent maternal allele, is a common human epigenetic population variant associated with a 5-fold increased frequency of colorectal neoplasia. Here, we show first that LOI leads specifically to increased expression of proliferation-related genes in mouse intestinal crypts. Surprisingly, LOI(+) mice also have enhanced sensitivity to IGF-II signaling, not simply increased IGF-II levels, because in vivo blockade with NVP-AEW541, a specific inhibitor of the IGF-II signaling receptor, showed reduction of proliferation-related gene expression to levels half that seen in LOI(-) mice. Signal transduction assays in microfluidic chips confirmed this enhanced sensitivity with marked augmentation of Akt/PKB signaling in LOI(+) cells at low doses of IGF-II, which was reduced in the presence of the inhibitor to levels below those found in LOI(-) cells, and was associated with increased expression of the IGF1 and insulin receptor genes. We exploited this increased IGF-II sensitivity to develop an in vivo chemopreventive strategy using the azoxymethane (AOM) mutagenesis model. LOI(+) mice treated with AOM showed a 60% increase in premalignant aberrant crypt foci (ACF) formation over LOI(-) mice. In vivo IGF-II blockade with NVP-AEW541 abrogated this effect, reducing ACF to a level 30% lower even than found in exposed LOI(-) mice. Thus, LOI increases cancer risk in a counterintuitive way, by increasing the sensitivity of the IGF-II signaling pathway itself, providing a previously undescribed epigenetic chemoprevention strategy in which cells with LOI are "IGF-II addicted" and undergo reduced tumorigenesis in the colon upon IGF-II pathway blockade.

  12. Enhanced sensitivity to IGF-II signaling links loss of imprinting of IGF2 to increased cell proliferation and tumor risk

    PubMed Central

    Kaneda, Atsushi; Wang, Chiaochun J.; Cheong, Raymond; Timp, Winston; Onyango, Patrick; Wen, Bo; Iacobuzio-Donahue, Christine A.; Ohlsson, Rolf; Andraos, Rita; Pearson, Mark A.; Sharov, Alexei A.; Longo, Dan L.; Ko, Minoru S. H.; Levchenko, Andre; Feinberg, Andrew P.

    2007-01-01

    Loss of imprinting (LOI) of the insulin-like growth factor-II gene (IGF2), leading to abnormal activation of the normally silent maternal allele, is a common human epigenetic population variant associated with a 5-fold increased frequency of colorectal neoplasia. Here, we show first that LOI leads specifically to increased expression of proliferation-related genes in mouse intestinal crypts. Surprisingly, LOI(+) mice also have enhanced sensitivity to IGF-II signaling, not simply increased IGF-II levels, because in vivo blockade with NVP-AEW541, a specific inhibitor of the IGF-II signaling receptor, showed reduction of proliferation-related gene expression to levels half that seen in LOI(−) mice. Signal transduction assays in microfluidic chips confirmed this enhanced sensitivity with marked augmentation of Akt/PKB signaling in LOI(+) cells at low doses of IGF-II, which was reduced in the presence of the inhibitor to levels below those found in LOI(−) cells, and was associated with increased expression of the IGF1 and insulin receptor genes. We exploited this increased IGF-II sensitivity to develop an in vivo chemopreventive strategy using the azoxymethane (AOM) mutagenesis model. LOI(+) mice treated with AOM showed a 60% increase in premalignant aberrant crypt foci (ACF) formation over LOI(−) mice. In vivo IGF-II blockade with NVP-AEW541 abrogated this effect, reducing ACF to a level 30% lower even than found in exposed LOI(−) mice. Thus, LOI increases cancer risk in a counterintuitive way, by increasing the sensitivity of the IGF-II signaling pathway itself, providing a previously undescribed epigenetic chemoprevention strategy in which cells with LOI are “IGF-II addicted” and undergo reduced tumorigenesis in the colon upon IGF-II pathway blockade. PMID:18087038

  13. The poplar basic helix-loop-helix transcription factor BEE3 - Like gene affects biomass production by enhancing proliferation of xylem cells in poplar.

    PubMed

    Noh, Seol Ah; Choi, Young-Im; Cho, Jin-Seong; Lee, Hyoshin

    2015-06-19

    Brassinosteroids (BRs) play important roles in many aspects of plant growth and development, including regulation of vascular cambium activities and cell elongation. BR-induced BEE3 (brassinosteroid enhanced expression 3) is required for a proper BR response. Here, we identified a poplar (Populus alba × Populus glandulosa) BEE3-like gene, PagBEE3L, encoding a putative basic helix-loop-helix (bHLH)-type transcription factor. Expression of PagBEE3L was induced by brassinolide (BL). Transcripts of PagBEE3L were mainly detected in stems, with the internode having a low level of transcription and the node having a relatively higher level. The function of the PagBEE3L gene was investigated through phenotypic analyses with PagBEE3L-overexpressing (ox) transgenic lines. This work particularly focused on a potential role of PagBEE3L in stem growth and development of polar. The PagBEE3L-ox poplar showed thicker and longer stems than wild-type plants. The xylem cells from the stems of PagBEE3L-ox plants revealed remarkably enhanced proliferation, resulting in an earlier thickening growth than wild-type plants. Therefore, this work suggests that xylem development of poplar is accelerated in PagBEE3L-ox plants and PagBEE3L plays a role in stem growth by increasing the proliferation of xylem cells to promote the initial thickening growth of poplar stems.

  14. The poplar basic helix-loop-helix transcription factor BEE3 – Like gene affects biomass production by enhancing proliferation of xylem cells in poplar

    SciTech Connect

    Noh, Seol Ah Choi, Young-Im Cho, Jin-Seong Lee, Hyoshin

    2015-06-19

    Brassinosteroids (BRs) play important roles in many aspects of plant growth and development, including regulation of vascular cambium activities and cell elongation. BR-induced BEE3 (brassinosteroid enhanced expression 3) is required for a proper BR response. Here, we identified a poplar (Populus alba × Populus glandulosa) BEE3-like gene, PagBEE3L, encoding a putative basic helix-loop-helix (bHLH)-type transcription factor. Expression of PagBEE3L was induced by brassinolide (BL). Transcripts of PagBEE3L were mainly detected in stems, with the internode having a low level of transcription and the node having a relatively higher level. The function of the PagBEE3L gene was investigated through phenotypic analyses with PagBEE3L-overexpressing (ox) transgenic lines. This work particularly focused on a potential role of PagBEE3L in stem growth and development of polar. The PagBEE3L-ox poplar showed thicker and longer stems than wild-type plants. The xylem cells from the stems of PagBEE3L-ox plants revealed remarkably enhanced proliferation, resulting in an earlier thickening growth than wild-type plants. Therefore, this work suggests that xylem development of poplar is accelerated in PagBEE3L-ox plants and PagBEE3L plays a role in stem growth by increasing the proliferation of xylem cells to promote the initial thickening growth of poplar stems. - Highlights: • We identify the BEE3-like gene form hybrid poplar (Populus alba × Populus glandulosa). • We examine effects of overexpression of PagBEE3L on growth in poplar. • We found that 35S:BEE3L transgenic plants showed more rapid growth than wild-type plants. • BEE3L protein plays an important role in the development of plant stem.

  15. The use of biomaterials for cell function enhancement: acceleration of fibroblast migration and promotion of stem cell proliferation

    NASA Astrophysics Data System (ADS)

    Qin, Sisi

    , while remained constant for the cells on the flat surfaces. The increased speed on the 8microm fiber surfaces could be correlated with a 20% increase in the nuclear deformation, and a decrease around 30% in the number of focal adhesion during the same observation period. RNA expression of Myosin IIA, a protein which complexes to the actin and is responsible for exertion of traction forces during migration was not upregulated during this process. On the other hand, histochemical staining of Myosin IIA showed that the protein had re-organized into large fibers which spanned the length of the cells. Observation of the cell morphology indicated that a new mode of motion had been established. Rather than the classical retraction of the cytoplasm followed by center of mass translation, which was observed on the flat surfaces, the cells were now moving by a contractile motion around the nucleus similar to that found in muscular motion. This mode was found to be more efficient when undergoing oriented motion. In addition to orientation, surface mechanics are also important in the tissue regeneration process. This study demonstrated that mechanical factors are important for the maintenance of pluripotency and control of proliferation rates. CD34+ hematopoietic stem cells (HSCs) were transduced with ICD (intracellular domain)-Notch and plated on gelatin hydrogels, whose moduli were controlled by the crosslinking ratio. On the softer hydrogel, a synergy was achieved which resulted in more than a five-fold increase in proliferation and a four-fold increase in the preservation of stemness, while HSCs maintained their ability to differentiate into multiple blood cell lineages. These results point the way for achieving clinically significant expansion of human HSCs.

  16. Prostate cancer stem-like cells proliferate slowly and resist etoposide-induced cytotoxicity via enhancing DNA damage response

    SciTech Connect

    Yan, Judy; Tang, Damu

    2014-10-15

    Despite the development of chemoresistance as a major concern in prostate cancer therapy, the underlying mechanisms remain elusive. In this report, we demonstrate that DU145-derived prostate cancer stem cells (PCSCs) progress slowly with more cells accumulating in the G1 phase in comparison to DU145 non-PCSCs. Consistent with the important role of the AKT pathway in promoting G1 progression, DU145 PCSCs were less sensitive to growth factor-induced activation of AKT in comparison to non-PCSCs. In response to etoposide (one of the most commonly used chemotherapeutic drugs), DU145 PCSCs survived significantly better than non-PCSCs. In addition to etoposide, PCSCs demonstrated increased resistance to docetaxel, a taxane drug that is commonly used to treat castration-resistant prostate cancer. Etoposide produced elevated levels of γH2AX and triggered a robust G2/M arrest along with a coordinated reduction of the G1 population in PCSCs compared to non-PCSCs, suggesting that elevated γH2AX plays a role in the resistance of PCSCs to etoposide-induced cytotoxicity. We have generated xenograft tumors from DU145 PCSCs and non-PCSCs. Consistent with the knowledge that PCSCs produce xenograft tumors with more advanced features, we were able to demonstrate that PCSC-derived xenograft tumors displayed higher levels of γH2AX and p-CHK1 compared to non-PCSC-produced xenograft tumors. Collectively, our research suggests that the elevation of DNA damage response contributes to PCSC-associated resistance to genotoxic reagents. - Highlights: • Increased survival in DU145 PCSCs following etoposide-induced cytotoxicity. • PCSCs exhibit increased sensitivity to etoposide-induced DDR. • Resistance to cytotoxicity may be due to slower proliferation in PCSCs. • Reduced kinetics to growth factor induced activation of AKT in PCSCs.

  17. Exendin-4 promotes liver cell proliferation and enhances the PDX-1-induced liver to pancreas transdifferentiation process.

    PubMed

    Aviv, Vered; Meivar-Levy, Irit; Rachmut, Itzhak H; Rubinek, Tamar; Mor, Eytan; Ferber, Sarah

    2009-11-27

    Over the last few years, evidence has accumulated revealing the unexpected potential of committed mammalian cells to convert to a different phenotype via a process called transdifferentiation or adult cell reprogramming. These findings may have major practical implications because this process may facilitate the generation of functional autologous tissues that can be used for replacing malfunctioning organs. An instructive role for transcription factors in diverting the developmental fate of cells in adult tissues has been demonstrated when adult human liver cells were induced to transdifferentiate to the pancreatic endocrine lineage upon ectopic expression of the pancreatic master regulator PDX-1 (pancreatic and duodenal homeobox gene 1). Since organogenesis and lineage commitment are affected also by developmental signals generated in response to environmental triggers, we have now analyzed whether the hormone GLP-1 (glucogen-like peptide-1) documented to play a role in pancreatic beta cell differentiation, maturation, and survival, can also increase the efficiency of liver to pancreas transdifferentiation. We demonstrate that the GLP-1R agonist, exendin-4, significantly improves the efficiency of PDX-1-mediated transdifferentiation. Exendin-4 affects the transdifferentiation process at two distinct steps; it increases the proliferation of liver cells predisposed to transdifferentiated in response to PDX-1 and promotes the maturation of transdifferentiated cells along the pancreatic lineage. Liver cell reprogramming toward the pancreatic beta cell lineage has been suggested as a strategy for functional replacement of the ablated insulin-producing cells in diabetics. Understanding the cellular and molecular basis of the transdifferentiation process will allow us to increase the efficiency of the reprogramming process and optimize its therapeutic merit.

  18. Downregulation of cytochrome c oxidase subunit 7A1 expression is important in enhancing cell proliferation in adenocarcinoma cells.

    PubMed

    Mishra, Nawneet; Timilsina, Uddhav; Ghimire, Dibya; Dubey, Ravi C; Gaur, Ritu

    2017-01-22

    Mitochondrial Dysfunction has been implicated in multiple human diseases, including cancer. Among all cancer, lung cancer is the most common type of cancer worldwide with low survival rates. Mammals possess multiple subunits of the mitochondrial enzyme Cytochrome C oxidase (COX). The COX subunits are expressed in a tissue specific manner and have been implicated in cancer cell metabolism although their molecular and regulatory mechanisms are not clearly understood. In this study, we aimed at identifying novel gene signatures in lung cancer. We performed extensive analysis of seven different Gene Expression Omnibus (GEO) datasets pertaining to different stages of lung adenocarcinoma and identified that multiple subunits of COX genes are differentially expressed in these patients. Amongst all COX genes, the expression of COX7A1 gene was observed to be highly down regulated in these patients. In order to validate the GEO datasets, we looked at the expression of multiple COX genes using quantitative real time PCR (qPCR) using human lung adenocarcinoma cell line A549. Our results confirmed that COX 7A1 gene expression was indeed highly reduced in these cells. Overexpression of COX7A1 in human lung cancer cells led to inhibition of cell proliferation and increase in cell death via apoptosis. These results indicated that low level of COX7A1 gene expression is essential to regulate cell viability and inhibit cell death in lung adenocarcinoma. Our study has identified COX7A1 as a novel gene that might play a crucial role in the etiology of lung adenocarcinoma and can serve as a biomarker for lung cancer disease progression.

  19. Grape seed proanthocyanidin extracts enhance endothelial nitric oxide synthase expression through 5'-AMP activated protein kinase/Surtuin 1-Krüpple like factor 2 pathway and modulate blood pressure in ouabain induced hypertensive rats.

    PubMed

    Cui, Xiaopei; Liu, Xiangju; Feng, Hua; Zhao, Shaohua; Gao, Haiqing

    2012-01-01

    Grape seed proanthocyanidin extracts (GSPE) belonging to polyphenols, possess various biological effects including anti-inflammation, anti-oxidant, anti-aging, anti-atherosclerosis, etc. GSPE is potential in regulating endothelial function. However, the underlying mechanism is not clear yet. In this study, by small interfering RNA (siRNA) knocking down, we proved that GSPE increase endothelial nitric oxide synthase (eNOS) expression in human umbilical vessel cells (HUVECs) in vitro, which was attributed to its transcription factor Krüpple like factor 2 (KLF2) induction. Furthermore, GSPE activate 5'-AMP activated protein kinase (AMPK) and increase surtuin 1 (SIRT1) protein level, critical for KLF2 induction. We also illuminated the role of GSPE in hypertension treatment. By chronic administration of GSPE in ouabain induced hypertensive rats model, we access the effect of GSPE on blood pressure regulation and the possible mechanisms involved. After 5 weeks feeding, GSPE significantly block the ouabain induced blood pressure increase. The aortic NO production impaired by ouabain was improved. In conclusion, GSPE increase eNOS expression and NO production in an AMPK/SIRT1 dependent manner through KLF2 induction, and attenuate ouabain induced hypertension.

  20. Olanzapine inhibits proliferation, migration and anchorage-independent growth in human glioblastoma cell lines and enhances temozolomide's antiproliferative effect.

    PubMed

    Karpel-Massler, Georg; Kast, Richard Eric; Westhoff, Mike-Andrew; Dwucet, Annika; Welscher, Nathalie; Nonnenmacher, Lisa; Hlavac, Michal; Siegelin, Markus David; Wirtz, Christian Rainer; Debatin, Klaus-Michael; Halatsch, Marc-Eric

    2015-03-01

    The poor prognosis of patients with glioblastoma fuels the search for more effective therapeutic compounds. We previously hypothesised that the neuroleptic olanzapine may enhance antineoplastic effects of temozolomide the standard chemotherapeutic agent used in this disease. This study tested this hypothesis. The anti-proliferative effect of olanzapine was examined by MTT assays and cell count analysis. Soft-agar assays were performed to examine colony-forming ability. In addition, the inhibitory effect of olanzapine on the migratory capacity of U87MG and A172 cells was analyzed by Transwell(®) assays. Moreover, staining for annexin V/propidium iodide or carboxyfluorescein succinimidyl ester was performed prior to flow cytometric analysis in order to better understand the subjacent cellular mechanism. Our initial hypothesis that olanzapine may enhance temozolomide's anti-tumor activity could be confirmed in U87MG and A172 glioblastoma cell lines. Moreover, treatment with olanzapine alone resulted in a marked anti-proliferative effect on U87MG, A172 and two glioma stem-like cells with IC50 values ranging from 25 to 79.9 µM. In U87MG cells, anchorage-independent growth was dose-dependently inhibited. In A172 cells, migration was also shown to be inhibited in a dose-dependent manner. In addition, olanzapine was shown to exert a cell line-dependent pleomorphism with respect to the induction of apoptosis, necrosis and/or cytostasis. Our data show that the neuroleptic olanzapine enhances the anti-tumor activity of temozolomide against glioblastoma cell lines. Moreover, this is the first study to show that olanzapine provides on its own anti-cancer activity in glioblastoma and thus may have potential for repurposing.

  1. Enhanced MET translation and signaling sustains K-Ras driven proliferation under anchorage-independent growth conditions

    PubMed Central

    Fujita-Sato, Saori; Galeas, Jacqueline; Truitt, Morgan; Pitt, Cameron; Urisman, Anatoly; Bandyopadhyay, Sourav; Ruggero, Davide; McCormick, Frank

    2015-01-01

    Oncogenic K-Ras mutation occurs frequently in several types of cancers including pancreatic and lung cancers. Tumors with K-Ras mutation are resistant to chemotherapeutic drugs as well as molecular targeting agents. Although numerous approaches are ongoing to find effective ways to treat these tumors, there are still no effective therapies for K-Ras mutant cancer patients. Here we report that K-Ras mutant cancers are more dependent on K-Ras in anchorage independent culture conditions than in monolayer culture conditions. In seeking to determine mechanisms that contribute to the K-Ras dependency in anchorage independent culture conditions, we discovered the involvement of Met in K-Ras-dependent, anchorage independent cell growth. The Met signaling pathway is enhanced and plays an indispensable role in anchorage independent growth even in cells in which Met is not amplified. Indeed, Met expression is elevated under anchorage-independent growth conditions and is regulated by K-Ras in a MAPK/ERK kinase (MEK)-dependent manner. Remarkably, in spite of a global down-regulation of mRNA translation during anchorage independent growth, we find that Met mRNA translation is specifically enhanced under these conditions. Importantly, ectopic expression of an active Met mutant rescues K-Ras ablation-derived growth suppression, indicating that K-Ras mediated Met expression drives “K-Ras addiction” in anchorage independent conditions. Our results indicate that enhanced Met expression and signaling is essential for anchorage independent growth of K-Ras mutant cancer cells and suggests that pharmacological inhibitors of Met could be effective for K-Ras mutant tumor patients. PMID:25977330

  2. Cooperation between AlphavBeta3 integrin and the fibroblast growth factor receptor enhances proliferation of Hox-overexpressing acute myeloid leukemia cells

    PubMed Central

    Shah, Chirag A.; Bei, Ling; Wang, Hao; Altman, Jessica K.; Platanias, Leonidas C.; Eklund, Elizabeth A.

    2016-01-01

    A poor prognosis subtype of acute myeloid leukemia (AML) is characterized by increased expression of a set of homeodomain (HD) transcription factors, including HoxA9, HoxA10 and Cdx4. This encompasses AML with MLL1 gene translocations, because Mll1-fusion proteins aberrantly activate HOX transcription. We previously identified FGF2 (Fibroblast Growth Factor 2) as a target gene for HoxA9 and HoxA10 that was indirectly activated by Mll-Ell (an Mll1-fusion protein). Autocrine stimulation of Mll-Ell+ myeloid progenitor cells by Fgf2 stabilized βcatenin and increased expression of βcatenin target genes, including CDX4. Since HOXA9 and HOXA10 are Cdx4 target genes, Fgf2 indirectly augmented direct effects of Mll-Ell on these genes. ITGB3, encoding β3 integrin, is another HoxA10 target gene. In the current studies, we found activation of ITGB3 transcription in Mll-Ell+ myeloid progenitor cells via HoxA9 and HoxA10. Increased expression of αvβ3 integrin increased Syk-activation; contributing to cytokine hypersensitivity. However, inhibiting Fgf-R partly reversed αvβ3 activity in Mll-Ell+ progenitor cells by decreasing ITGB3 promoter activity in a βcatenin- and Cdx4-dependent manner. Inhibitors of Fgf-R or Syk impaired proliferation of CD34+ bone marrow cells from AML subjects with increased Hox-expression; with a greater combined effect. These studies identified a rational therapeutic approach to this AML subtype. PMID:27340869

  3. Enhanced HSP70 lysine methylation promotes proliferation of cancer cells through activation of Aurora kinase B

    PubMed Central

    Cho, Hyun-Soo; Shimazu, Tadahiro; Toyokawa, Gouji; Daigo, Yataro; Maehara, Yoshihiko; Hayami, Shinya; Ito, Akihiro; Masuda, Ken; Ikawa, Noriko; Field, Helen I.; Tsuchiya, Eiju; Ohnuma, Shin-ichi; Ponder, Bruce A.J.; Yoshida, Minoru; Nakamura, Yusuke; Hamamoto, Ryuji

    2012-01-01

    Although heat-shock protein 70 (HSP70), an evolutionarily highly conserved molecular chaperone, is known to be post-translationally modified in various ways such as phosphorylation, ubiquitination and glycosylation, physiological significance of lysine methylation has never been elucidated. Here we identify dimethylation of HSP70 at Lys-561 by SETD1A. Enhanced HSP70 methylation was detected in various types of human cancer by immunohistochemical analysis, although the methylation was barely detectable in corresponding non-neoplastic tissues. Interestingly, methylated HSP70 predominantly localizes to the nucleus of cancer cells, whereas most of the HSP70 protein locates to the cytoplasm. Nuclear HSP70 directly interacts with Aurora kinase B (AURKB) in a methylation-dependent manner and promotes AURKB activity in vitro and in vivo. We also find that methylated HSP70 has a growth-promoting effect in cancer cells. Our findings demonstrate a crucial role of HSP70 methylation in human carcinogenesis. PMID:22990868

  4. Colony-stimulating factor 2 enhances the developmental competence of yak (Poephagus grunniens) preimplantation embryos by modulating the expression of heat shock protein 70 kDa 1A.

    PubMed

    Wen, Zexing; Pan, Yangyang; Cui, Yan; Peng, Xiumei; Chen, Ping; Fan, Jiangfeng; Li, Guyue; Zhao, Tian; Zhang, Jian; Qin, Shujian; Yu, Sijiu

    2017-04-15

    Colony-stimulating factor 2 (CSF2) is known to promote the development and survival of rodents and ruminants preimplantation embryos; however, the effect of CSF2 on yak embryos has not been reported. The objective of this study was to investigate the effects of CSF2 on the developmental competence of yak embryos cultured in vitro in modified synthetic oviduct fluid (mSOF) medium and on the expression pattern of heat shock protein 70 kDa 1A (HSPA1A). In each experiment, cumulus-oocyte complexes (COCs) were matured in vitro and fertilized with frozen-thawed semen. Zygotes were treated with varying concentrations of CSF2 (0, 10, 50, 100 ng/mL) until day 8 after fertilization. Embryo development was calculated as the percentage of oocytes that formed embryos at the 2-cell, 4-cell, 8-cell, 16-cell, morula and blastocyst stages. The total cell numbers (TCN) per blastocyst and their allocation to the inner cell mass (ICM) and trophectoderm (TE) lineages were determined using differential CDX2 staining. The expression of HSPA1A was examined by quantitative real-time PCR (qRT-PCR) and immunochemistry to determine the mRNA and protein levels. The results showed that treatment with 50 ng/mL CSF2 significantly (P < 0.05) increased the rate of blastocyst formation (19.01% versus 9.93%) and the TCN per blastocyst (96.94 versus 81.41) compared to the control group. However, no significant differences were observed in the other stages of development. qRT-PCR analysis confirmed that treatment with 50 ng/mL CSF2 significantly (P < 0.05) inhibited the expression of HSPA1A mRNA in blastocysts cultured in vitro relative to the control group, but there were no significant differences between the other treatment groups. Immunocytochemical analysis confirmed that HSPA1A protein accumulation was gradually reduced in yak blastocysts cultured in 0, 10, 100 or 50 ng/mL CSF2, however, no significant differences were observed between the 10 and 100 ng/mL treatments (P > 0.05). In

  5. Enhanced proliferation and osteogenic differentiation of mesenchymal stem cells on graphene oxide-incorporated electrospun poly(lactic-co-glycolic acid) nanofibrous mats.

    PubMed

    Luo, Yu; Shen, He; Fang, Yongxiang; Cao, Yuhua; Huang, Jie; Zhang, Mengxin; Dai, Jianwu; Shi, Xiangyang; Zhang, Zhijun

    2015-03-25

    Currently, combining biomaterial scaffolds with living stem cells for tissue regeneration is a main approach for tissue engineering. Mesenchymal stem cells (MSCs) are promising candidates for musculoskeletal tissue repair through differentiating into specific tissues, such as bone, muscle, and cartilage. Thus, successfully directing the fate of MSCs through factors and inducers would improve regeneration efficiency. Here, we report the fabrication of graphene oxide (GO)-doped poly(lactic-co-glycolic acid) (PLGA) nanofiber scaffolds via electrospinning technique for the enhancement of osteogenic differentiation of MSCs. GO-PLGA nanofibrous mats with three-dimensional porous structure and smooth surface can be readily produced via an electrospinning technique. GO plays two roles in the nanofibrous mats: first, it enhances the hydrophilic performance, and protein- and inducer-adsorption ability of the nanofibers. Second, the incorporated GO accelerates the human MSCs (hMSCs) adhesion and proliferation versus pure PLGA nanofiber and induces the osteogenic differentiation. The incorporating GO scaffold materials may find applications in tissue engineering and other fields.

  6. Overexpression of CRABPI in suprabasal keratinocytes enhances the proliferation of epidermal basal keratinocytes in mouse skin topically treated with all-trans retinoic acid.

    PubMed

    Tang, Xiao-Han; Vivero, Marina; Gudas, Lorraine J

    2008-01-01

    We investigated whether ectopic expression of CRABPI, a cellular retinoic acid binding protein, influenced the actions of all-trans retinoic acid (ATRA) in transgenic (TG) mice. We targeted CRABPI to the basal vs. suprabasal layers of mouse epidermis by using the keratin 14 (K14) and keratin 10 (K10) promoters, respectively. Greater CRABPI protein levels were detected in the epidermis of adult transgenic(+) mice than in transgenic(-) mice for both transgenes. In adult mouse skin CRABPI overexpression in the basal or suprabasal keratinocytes did not cause morphological abnormalities, but did result in decreased CRABPII mRNA levels. Ectopically overexpressed CRABPI in suprabasal keratinocytes, but not in basal keratinocytes, enhanced the thickening of the epidermis induced by topical ATRA treatments (10 microM, 400 microl for 4 days) by 1.59+/-0.2-fold (p<0.05). ATRA treatment (10 microM) resulted in a 59.9+/-9.8% increase (p<0.05) in the BrdU labeling index in K10/FLAG-CRABPI TG(+) mice vs. TG(-) mice. Retinoid topical treatments reduced p27 and CYP26A1 mRNA levels in TG(+) and TG(-) mouse skin in K14 and K10/FLAG-CRABPI transgenic mice. As epidermal basal keratinocyte proliferation is stimulated by paracrine growth factors secreted by ATRA activated suprabasal keratinocytes, our results indicate that CRABPI overexpression in suprabasal keratinocytes enhances the physiological functions of ATRA.

  7. Overexpression of CRABPI in suprabasal keratinocytes enhances the proliferation of epidermal basal keratinocytes in mouse skin topically treated with all-trans retinoic acid

    SciTech Connect

    Tang, X.-H.; Vivero, Marina; Gudas, Lorraine J.

    2008-01-01

    We investigated whether ectopic expression of CRABPI, a cellular retinoic acid binding protein, influenced the actions of all-trans retinoic acid (ATRA) in transgenic (TG) mice. We targeted CRABPI to the basal vs. suprabasal layers of mouse epidermis by using the keratin 14 (K14) and keratin 10 (K10) promoters, respectively. Greater CRABPI protein levels were detected in the epidermis of adult transgenic(+) mice than in transgenic(-) mice for both transgenes. In adult mouse skin CRABPI overexpression in the basal or suprabasal keratinocytes did not cause morphological abnormalities, but did result in decreased CRABPII mRNA levels. Ectopically overexpressed CRABPI in suprabasal keratinocytes, but not in basal keratinocytes, enhanced the thickening of the epidermis induced by topical ATRA treatments (10 {mu}M, 400 {mu}l for 4 days) by 1.59 {+-} 0.2-fold (p < 0.05). ATRA treatment (10 {mu}M) resulted in a 59.9 {+-} 9.8% increase (p < 0.05) in the BrdU labeling index in K10/FLAG-CRABPI TG(+) mice vs. TG(-) mice. Retinoid topical treatments reduced p27 and CYP26A1 mRNA levels in TG(+) and TG(-) mouse skin in K14 and K10/FLAG-CRABPI transgenic mice. As epidermal basal keratinocyte proliferation is stimulated by paracrine growth factors secreted by ATRA activated suprabasal keratinocytes, our results indicate that CRABPI overexpression in suprabasal keratinocytes enhances the physiological functions of ATRA.

  8. Post Treatment With an FGF Chimeric Growth Factor Enhances Epithelial Cell Proliferation to Improve Recovery From Radiation-Induced Intestinal Damage

    SciTech Connect

    Nakayama, Fumiaki; Hagiwara, Akiko; Umeda, Sachiko; Asada, Masahiro; Goto, Megumi; Oki, Junko; Suzuki, Masashi; Imamura, Toru; Akashi, Makoto

    2010-11-01

    Purpose: A fibroblast growth factor (FGF) 1-FGF2 chimera (FGFC) was created previously and showed greater structural stability than FGF1. This chimera was capable of stimulating epithelial cell proliferation much more strongly than FGF1 or FGF2 even without heparin. Therefore FGFC was expected to have greater biologic activity in vivo. This study evaluated and compared the protective activity of FGFC and FGF1 against radiation-induced intestinal injuries. Methods and Materials: We administered FGFC and FGF1 intraperitoneally to BALB/c mice 24 h before or after total-body irradiation (TBI). The numbers of surviving crypts were determined 3.5 days after TBI with gamma rays at doses ranging from 8 to 12 Gy. Results: The effect of FGFC was equal to or slightly superior to FGF1 with heparin. However, FGFC was significantly more effective in promoting crypt survival than FGF1 (p < 0.01) when 10 {mu}g of each FGF was administered without heparin before irradiation. In addition, FGFC was significantly more effective at promoting crypt survival (p < 0.05) than FGF1 even when administered without heparin at 24 h after TBI at 10, 11, or 12 Gy. We found that FGFC post treatment significantly promoted 5-bromo-2'-deoxyuridine incorporation into crypts and increased crypt depth, resulting in more epithelial differentiation. However, the number of apoptotic cells in FGFC-treated mice decreased to almost the same level as that in FGF1-treated mice. Conclusions: These findings suggest that FGFC strongly enhanced radioprotection with the induction of epithelial proliferation without exogenous heparin after irradiation and is useful in clinical applications for both the prevention and post treatment of radiation injuries.

  9. Enhanced Gastrointestinal Expression of Cytosolic Malic Enzyme (ME1) Induces Intestinal and Liver Lipogenic Gene Expression and Intestinal Cell Proliferation in Mice

    PubMed Central

    Al-Dwairi, Ahmed; Brown, Adam R.; Pabona, John Mark P.; Van, Trang H.; Hamdan, Hamdan; Mercado, Charles P.; Quick, Charles M.; Wight, Patricia A.; Simmen, Rosalia C. M.; Simmen, Frank A.

    2014-01-01

    The small intestine participates in lipid digestion, metabolism and transport. Cytosolic malic enzyme 1 (ME1) is an enzyme that generates NADPH used in fatty acid and cholesterol biosynthesis. Previous work has correlated liver and adipose ME1 expression with susceptibility to obesity and diabetes; however, the contributions of intestine-expressed ME1 to these conditions are unknown. We generated transgenic (Tg) mice expressing rat ME1 in the gastrointestinal epithelium under the control of the murine villin1 promoter/enhancer. Levels of intestinal ME1 protein (endogenous plus transgene) were greater in Tg than wildtype (WT) littermates. Effects of elevated intestinal ME1 on body weight, circulating insulin, select adipocytokines, blood glucose, and metabolism-related genes were examined. Male Tg mice fed a high-fat (HF) diet gained significantly more body weight than WT male littermates and had heavier livers. ME1-Tg mice had deeper intestinal and colon crypts, a greater intestinal 5-bromodeoxyuridine labeling index, and increased expression of intestinal lipogenic (Fasn, Srebf1) and cholesterol biosynthetic (Hmgcsr, Hmgcs1), genes. The livers from HF diet-fed Tg mice also exhibited an induction of cholesterol and lipogenic pathway genes and altered measures (Irs1, Irs2, Prkce) of insulin sensitivity. Results indicate that gastrointestinal ME1 via its influence on intestinal epithelial proliferation, and lipogenic and cholesterologenic genes may concomitantly impact signaling in liver to modify this tissue’s metabolic state. Our work highlights a new mouse model to address the role of intestine-expressed ME1 in whole body metabolism, hepatomegaly, and crypt cell proliferation. Intestinal ME1 may thus constitute a therapeutic target to reduce obesity-associated pathologies. PMID:25402228

  10. Gamma aminobutyric acid B and 5-hydroxy tryptamine 2A receptors functional regulation during enhanced liver cell proliferation by GABA and 5-HT chitosan nanoparticles treatment.

    PubMed

    Shilpa, Joy; Pretty, Mary Abraham; Anitha, Malat; Paulose, Cheramadathikudyil Skaria

    2013-09-05

    Liver is one of the major organs in vertebrates and hepatocytes are damaged by many factors. The liver cell maintenance and multiplication after injury and treatment gained immense interest. The present study investigated the role of Gamma aminobutyric acid (GABA) and serotonin or 5-hydroxytryptamine (5-HT) coupled with chitosan nanoparticles in the functional regulation of Gamma aminobutyric acid B and 5-hydroxy tryptamine 2A receptors mediated cell signaling mechanisms, extend of DNA methylation and superoxide dismutase activity during enhanced liver cell proliferation. Liver injury was achieved by partial hepatectomy of male Wistar rats and the GABA and 5-HT chitosan nanoparticles treatments were given intraperitoneally. The experimental groups were sham operated control (C), partially hepatectomised rats with no treatment (PHNT), partially hepatectomised rats with GABA chitosan nanoparticle (GCNP), 5-HT chitosan nanoparticle (SCNP) and a combination of GABA and 5-HT chitosan nanoparticle (GSCNP) treatments. In GABA and 5-HT chitosan nanoparticle treated group there was a significant decrease (P<0.001) in the receptor expression of Gamma aminobutyric acid B and a significant increase (P<0.001) in the receptor expression of 5-hydroxy tryptamine 2A when compared to PHNT. The cyclic adenosine monophosphate content and its regulatory protein, presence of methylated DNA and superoxide dismutase activity were decreased in GCNP, SCNP and GSCNP when compared to PHNT. The Gamma aminobutyric acid B and 5-hydroxy tryptamine 2A receptors coupled signaling elements played an important role in GABA and 5-HT chitosan nanoparticles induced liver cell proliferation which has therapeutic significance in liver disease management.

  11. Short-term ursolic acid promotes skeletal muscle rejuvenation through enhancing of SIRT1 expression and satellite cells proliferation.

    PubMed

    Bakhtiari, Nuredin; Hosseinkhani, Saman; Soleimani, Masoud; Hemmati, Roohullah; Noori-Zadeh, Ali; Javan, Mohammad; Tashakor, Amin

    2016-03-01

    Ursolic acid (UA) is a triterpenoid compound, which exerts its influences on the skeletal muscles. However, the mechanisms underlying these effects are still unclear. In this study, muscle satellite cells were isolated and purified by high-throughput pre-plating method (∼>60%) from 10 days old mice skeletal muscles. Evaluation of paired-box 7 (Pax7) expressions then confirmed the purification. Treatment of the cells with UA showed that UA up-regulated SIRT1 (∼35 folds) and overexpressed PGC-1α (∼175 folds) gene significantly. Moreover, the number of muscle satellite cells, which accompanied by initiation of neomyogenesis in the animal skeletal muscles, was increased (∼3.4 times). We also evaluated UA-mediated changes in the cellular energy status in the skeletal muscles. The results revealed that in the UA-treated mice, ATP and ADP contents in the various skeletal muscle tissue types, including: Gastrocnemius (Gas), Tibialis Anterior (Tib) and Gluteus Maximus (Glu) have been significantly decreased (P≤0.001); 2.2, 3.2, 2 times for ATP, and 9.6, 35.7, 11.6 times for ADP, respectively; however to compensate this process mitochondrial biogenesis occurred (12.33%±1.5 times). Furthermore, a rise in ATP/ADP ratio was observed 2.5, 4.5, 2.05 times for Gas, Tib and Glu muscles, respectively (P≤0.001). Alternatively, UA enhanced the expression of myoglobin (∼2 folds) in concert with remodeling of glycolytic muscle fibers to mainly fast IIA (∼30%) and slow-twitch (∼4%) types as well. Finally, our study indicated that UA indirectly mimicked beneficial effects of short-term calorie restriction and exercise (fast-oxidative) by directing the skeletal muscle composition toward oxidative metabolism.

  12. Ubiquitin C-terminal hydrolase L1 (UCH-L1) acts as a novel potentiator of cyclin-dependent kinases to enhance cell proliferation independently of its hydrolase activity.

    PubMed

    Kabuta, Tomohiro; Mitsui, Takeshi; Takahashi, Masaki; Fujiwara, Yuuki; Kabuta, Chihana; Konya, Chiho; Tsuchiya, Yukihiro; Hatanaka, Yusuke; Uchida, Kenko; Hohjoh, Hirohiko; Wada, Keiji

    2013-05-03

    Dysregulation of cell proliferation and the cell cycle are associated with various diseases, such as cancer. Cyclin-dependent kinases (CDKs) play central roles in cell proliferation and the cell cycle. Ubiquitin C-terminal hydrolase L1 (UCH-L1) is expressed in a restricted range of tissues, including the brain and numerous types of cancer. However, the molecular functions of UCH-L1 remain elusive. In this study, we found that UCH-L1 physically interacts with CDK1, CDK4, and CDK5, enhancing their kinase activity. Using several mutants of UCH-L1, we showed that this enhancement is dependent upon interaction levels between UCH-L1 and CDKs but is independent of the known ubiquitin-related functions of UCH-L1. Gain- and loss-of-function studies revealed that UCH-L1 enhances proliferation of multiple cell types, including human cancer cells. Inhibition of the interaction between UCH-L1 and cell cycle-associated CDK resulted in the abolishment of UCH-L1-induced enhancement of cell proliferation. RNA interference of UCH-L1 reduced the growth of human xenograft tumors in mice. We concluded that UCH-L1 is a novel regulator of the kinase activities of CDKs. We believe that our findings from this study will significantly contribute to our understanding of cell cycle-associated diseases.

  13. Action Mechanism of Fibroblast Growth Factor-2 (FGF-2) in the Promotion of Periodontal Regeneration in Beagle Dogs.

    PubMed

    Nagayasu-Tanaka, Toshie; Anzai, Jun; Takaki, Shu; Shiraishi, Noriko; Terashima, Akio; Asano, Taiji; Nozaki, Takenori; Kitamura, Masahiro; Murakami, Shinya

    2015-01-01

    Fibroblast growth factor-2 (FGF-2) enhances the formation of new alveolar bone, cementum, and periodontal ligament (PDL) in periodontal defect models. However, the mechanism through which FGF-2 acts in periodontal regeneration in vivo has not been fully clarified yet. To reveal the action mechanism, the formation of regenerated tissue and gene expression at the early phase were analyzed in a beagle dog 3-wall periodontal defect model. FGF-2 (0.3%) or the vehicle (hydroxypropyl cellulose) only were topically applied to the defect in FGF-2 and control groups, respectively. Then, the amount of regenerated tissues and the number of proliferating cells at 3, 7, 14, and 28 days and the number of blood vessels at 7 days were quantitated histologically. Additionally, the expression of osteogenic genes in the regenerated tissue was evaluated by real-time PCR at 7 and 14 days. Compared with the control, cell proliferation around the existing bone and PDL, connective tissue formation on the root surface, and new bone formation in the defect at 7 days were significantly promoted by FGF-2. Additionally, the number of blood vessels at 7 days was increased by FGF-2 treatment. At 28 days, new cementum and PDL were extended by FGF-2. Moreover, FGF-2 increased the expression of bone morphogenetic protein 2 (BMP-2) and osteoblast differentiation markers (osterix, alkaline phosphatase, and osteocalcin) in the regenerated tissue. We revealed the facilitatory mechanisms of FGF-2 in periodontal regeneration in vivo. First, the proliferation of fibroblastic cells derived from bone marrow and PDL was accelerated and enhanced by FGF-2. Second, angiogenesis was enhanced by FGF-2 treatment. Finally, osteoblastic differentiation and bone formation, at least in part due to BMP-2 production, were rapidly induced by FGF-2. Therefore, these multifaceted effects of FGF-2 promote new tissue formation at the early regeneration phase, leading to enhanced formation of new bone, cementum, and PDL.

  14. Visualization of microvascular proliferation as a tumor infiltration structure in rat glioma specimens using the diffraction-enhanced imaging in-plane CT technique

    NASA Astrophysics Data System (ADS)

    Seo, Seung-Jun; Sunaguchi, Naoki; Yuasa, Tetsuya; Huo, Qingkai; Ando, Masami; Choi, Gi-Hwan; Kim, Hong-Tae; Kim, Ki-Hong; Jeong, Eun-Ju; Chang, Won-Seok; Kim, Jong-Ki

    2012-03-01

    In order to study potent microenvironments of malignant gliomas with a high- resolution x-ray imaging technique, an injection orthotopic glioma model was made using the Sprague-Dawley rat. Total brain tissue, taken out as an ex vivo model, was examined with diffraction-enhanced imaging (DEI) computed tomography (CT) acquired with a 35 keV monochromatic x-ray. In the convolution-reconstructed 2D/3D images with a spatial resolution of 12.5 × 12.5 × 25 µm, distinction among necrosis, typical ring-shaped viable tumors, edemas and healthy tissues was clearly observed near the frontal lobe in front of the rat's caudate nucleus. Multiple microvascular proliferations (MVPs) were observed surrounding peritumoral edemas as a tumor infiltration structure. Typical dimensions of tubular MVPs were 130 (diameter) ×250 (length) µm with a partial sprout structure revealed in the 3D reconstructed image. Hyperplasia of cells around vessel walls was revealed with tumor cell infiltration along the perivascular space in microscopic observations of mild MVP during histological analysis. In conclusion, DEI-CT is capable of imaging potent tumor-infiltrating MVP structures surrounding high-grade gliomas.

  15. A three-dimensional hierarchical collagen scaffold fabricated by a combined solid freeform fabrication (SFF) and electrospinning process to enhance mesenchymal stem cell (MSC) proliferation

    NASA Astrophysics Data System (ADS)

    Ahn, SeungHyun; Koh, Young Ho; Kim, GeunHyung

    2010-06-01

    Collagen has the advantage of being very similar to macromolecular substances that can be recognized and metabolized in the biological environment. Although the natural material has superior property for this purpose, its use to fabricate reproducible and pore-structure-controlled 3D structures, which are designed to allow the entry of sufficient cells and the easy diffusion of nutrients, has been limited due to its low processability. Here, we propose a hybrid technology that combines a cryogenic plotting system with an electrospinning process. Using this technique, an easily pore-size-controllable hierarchical 3D scaffold consisting of micro-sized highly porous collagen strands and micro/nano-sized collagen fibers was fabricated. The pore structure of the collagen scaffold was controlled by the collagen micro/nanofibers, which were layered in the scaffold. The hierarchical scaffolds were characterized with respect to initial cell attachment and proliferation of bone marrow-derived mesenchymal stem cells within the scaffolds. The hierarchical scaffold exhibited incredibly enhanced initial cell attachment and cell compactness between pores of the plotted scaffold relative to the normally designed 3D collagen scaffold.

  16. Graphene oxide as an anaerobic membrane scaffold for the enhancement of B. adolescentis proliferation and antagonistic effects against pathogens E. coli and S. aureus

    NASA Astrophysics Data System (ADS)

    Chen, Han-qing; Gao, Di; Wang, Bing; Zhao, Rui-fang; Guan, Ming; Zheng, Ling-na; Zhou, Xiao-yan; Chai, Zhi-fang; Feng, Wei-yue

    2014-04-01

    The impact of the gut microbiota on human health is widely perceived as the most exciting advancement in biomedicine. The gut microbiota has been known to play a crucial role in defining states of human health and diseases, and thus becomes a potential new territory for drug targeting. Herein, graphene oxide (GO) interaction with five common human gut bacteria, B. adolescentis, L. acidophilus, E. coli, E. faecalis, and S. aureus, was studied. It was shown that, in bacterial media, GO sheets were able to form effective, anaerobic membrane scaffolds that enhanced the antagonistic activity of B. adolescentis against the pathogens E. coli andS. aureus. Data obtained using bacterial growth measurements, colony counting and 16S rRNA gene sequencing consistently indicated that GO sheets promoted proliferation of gut bacteria, particularly for B. adolescentis. Scanning electron microscopy, atomic force microscopy images, and membrane potential measurements showed that cell membranes maintained their integrity and that no observable variations in cell morphology were induced after interaction with GO sheets, indicating good biocompatibility of GO. These results suggest the possibility of using GO sheets as efficient drug carriers in therapeutic applications to treat diseases related to the gut microbiota.

  17. Dexamethasone enhances insulin-like growth factor-I effects on skeletal muscle cell proliferation. Role of specific intracellular signaling pathways.

    PubMed Central

    Giorgino, F; Smith, R J

    1995-01-01

    IGF-I stimulation of cell proliferation and c-Fos expression in skeletal muscle cells is markedly enhanced by dexamethasone. The effect of dexamethasone is not mediated by changes in IGF-binding proteins, as evidenced by similar effects of dexamethasone on the actions of insulin, PDGF-BB, and the IGF-I analogue long R3IGF-I. Dexamethasone also does not alter autocrine IGF-II secretion by muscle cells. To investigate the mechanism of the augmentation of IGF-I action, the effects of dexamethasone on intracellular IGF-I signaling pathways were determined. In dexamethasone-treated cells, the levels of IGF-I receptor tyrosine phosphorylation and receptor-associated phosphatidylinositol 3-kinase activity were increased. Dexamethasone-treated cells also showed increased and prolonged tyrosine phosphorylation of the Shc proteins. In contrast, dexamethasone decreased both tyrosine phosphorylation and expression of insulin receptor substrate 1 (IRS-1) and IRS-1-associated phosphatidylinositol 3-kinase activity. Thus, distinct signaling pathways activated by the IGF-I receptor in skeletal muscle cells are differentially regulated by dexamethasone. Potentiation of IGF-I action correlates with increased IGF-I receptor-associated phosphatidylinositol 3-kinase activity and tyrosine phosphorylation of Shc, but appears to be independent of activation of the IRS-1/phosphatidylinositol 3-kinase signaling pathway. Images PMID:7544807

  18. OSI-027 inhibits pancreatic ductal adenocarcinoma cell proliferation and enhances the therapeutic effect of gemcitabine both in vitro and in vivo.

    PubMed

    Zhi, Xiao; Chen, Wei; Xue, Fei; Liang, Chao; Chen, Bryan Wei; Zhou, Yue; Wen, Liang; Hu, Liqiang; Shen, Jian; Bai, Xueli; Liang, Tingbo

    2015-09-22

    Despite its relative rarity, pancreatic ductal adenocarcinoma (PDAC) accounts for a large percentage of cancer deaths. In this study, we investigated the in vitro efficacy of OSI-027, a selective inhibitor of mammalian target of rapamycin complex 1 (mTORC1) and mTORC2, to treat PDAC cell lines alone, and in combination with gemcitabine (GEM). Similarly, we tested the efficacy of these two compounds in a xenograft mouse model of PDAC. OSI-027 significantly arrested cell cycle in G0/G1 phase, inhibited the proliferation of Panc-1, BxPC-3, and CFPAC-1 cells, and downregulated mTORC1, mTORC2, phospho-Akt, phospho-p70S6K, phospho-4E-BP1, cyclin D1, and cyclin-dependent kinase 4 (CDK4) in these cells. Moreover, OSI-027 also downregulated multidrug resistance (MDR)-1, which has been implicated in chemotherapy resistance in PDAC cells and enhanced apoptosis induced by GEM in the three PDAC cell lines. When combined, OSI-027 with GEM showed synergistic cytotoxic effects both in vitro and in vivo. This is the first evidence of the efficacy of OSI-027 in PDAC and may provide the groundwork for a new clinical PDAC therapy.

  19. Sequential changes of extracellular matrix and proliferation of Ito cells with enhanced expression of desmin and actin in focal hepatic injury.

    PubMed Central

    Ogawa, K.; Suzuki, J.; Mukai, H.; Mori, M.

    1986-01-01

    Immunohistochemical investigations were carried out on the properties of the cells and extracellular matrix (ECM) in focal hepatic injuries. A liquid nitrogen-cooled syringe needle was thrust into the rat liver. Necrotic areas became permeated with plasma within 24-hour period. Areas became strongly positive for fibronectin and were infiltrated with inflammatory cells positive for lysozyme. By the third day, Ito cells were proliferated in the peripheral portions of the damaged areas. These Ito cells showed enhanced immunostaining for desmin and actin but were negative for lysozyme. Interstitial fibers which were immunochemically positive for Types I and IV collagens, laminin, and fibronectin, began to increase from Day 3. They appeared on the rim of the hepatocytes adjacent to the damaged areas and extended into the injured regions with the Ito cells. An increase in basal laminas associated with capillaries and bile ducts also increased with a 1-day delay. The damaged areas were replaced by granulation tissue by Day 5. A rapid diminution then occurred in the granulation tissue, and normal hepatic tissue was restored in 7-10 days. These observations demonstrate that ECM changed in a sequential manner and then finally disappeared from the damaged site within 10 days. Although various cells, including parenchymal cells, macrophages, endothelial cells, and cholangiolar cells contributed to the healing of the damaged area, Ito cells, which exhibit unique phenotypic changes, presumably had a major role in the process. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:3799820

  20. Smenospongidine suppresses the proliferation of multiple myeloma cells by promoting CCAAT/enhancer-binding protein homologous protein-mediated β-catenin degradation.

    PubMed

    Park, Seoyoung; Hwang, In Hyun; Kim, Jiseon; Chung, Young-Hwa; Song, Gyu-Young; Na, MinKyun; Oh, Sangtaek

    2017-03-08

    Abnormal up-regulation of β-catenin expression is associated with the development and progression of multiple myeloma and is thus a potential therapeutic target. Here, we screened cell-based natural compounds and identified smenospongidine, a metabolite isolated from a marine sponge, as an antagonist of the Wnt/β-catenin signaling pathway. Smenospongidine promoted the degradation of intracellular β-catenin that accumulated via Wnt3a or 6-bromoindirubin-3'-oxime, an inhibitor of glycogen synthase kinase-3β. Consistently, smenospongidine down-regulated β-catenin expression and repressed the levels of β-catenin/T cell factor-dependent genes such as axin2, c-myc, and cyclin D1 in RPMI-8226 multiple myeloma cells. Smenospongidine suppressed proliferation and significantly induced apoptosis in RPMI-8266 cells. In addition, smenospongidine-induced β-catenin degradation was mediated by up-regulating CCAAT/enhancer-binding protein homologous protein (CHOP). These findings indicate that smenospongidine exerts its anti-proliferative activity by blocking the Wnt/β-catenin signaling pathway and may be a potential chemotherapeutic agent against multiple myeloma.

  1. Enhancement of cell ingrowth, proliferation, and early differentiation in a three-dimensional silicon carbide scaffold using low-intensity pulsed ultrasound.

    PubMed

    Wu, Lin; Lin, Liangjun; Qin, Yi-Xian

    2015-01-01

    the sham control group, respectively. Alkaline phosphatase activity was significantly increased by the treatment of ultrasound at 4 (p=0.012) and 7 days (p=0.035). These results suggested that ultrasound treatment with low-intensity acoustic energy facilitated the cellular ingrowth and enhanced the proliferation and early differentiation of osteoblasts in SiC scaffolds.

  2. Enhancement of Cell Ingrowth, Proliferation, and Early Differentiation in a Three-Dimensional Silicon Carbide Scaffold Using Low-Intensity Pulsed Ultrasound

    PubMed Central

    Lin, Liangjun

    2015-01-01

    the sham control group, respectively. Alkaline phosphatase activity was significantly increased by the treatment of ultrasound at 4 (p=0.012) and 7 days (p=0.035). These results suggested that ultrasound treatment with low-intensity acoustic energy facilitated the cellular ingrowth and enhanced the proliferation and early differentiation of osteoblasts in SiC scaffolds. PMID:24935158

  3. miR-203 facilitates tumor growth and metastasis by targeting fibroblast growth factor 2 in breast cancer

    PubMed Central

    He, Shuqian; Zhang, Guihui; Dong, He; Ma, Maoqiang; Sun, Qing

    2016-01-01

    Breast cancer is the second leading cause of cancer mortality in women worldwide. Molecular therapy is needed to improve the outcome in patients with breast cancer. miR-203 participates in cancer cell proliferation, transformation, and apoptosis. This study showed that miR-203 was upregulated in breast cancer tissues and the MCF-7 cell line. miR-203 knockdown suppressed colony formation and transformation and also limited migration in MCF-7 cells. Fibroblast growth factor 2 (FGF2) was confirmed as a novel target of miR-203, as miR-203 knockdown induced an enhanced expression of FGF2 in MCF-7 cells. Moreover, FGF2 can reverse transforming growth factor-β signal pathway to suppress breast cancer. These findings provide new insights with potential therapeutic applications for the treatment of breast cancer. PMID:27785068

  4. [Regulation of myostatin promoter activity by myocyte enhancer factor 2].

    PubMed

    Li, Jia; Deng, Jie; Zhang, Junlin; Cheng, De; Wang, Huayan

    2012-08-01

    Myostatin (Mstn) is a member of the transforming growth factor-beta superfamily that functions as a negative regulator of skeletal muscle growth and differentiation in mammals. The transcriptional regulation of Mstn is controlled by multiple genes including MEF2, which raise the importance of identifying the binding sites of MEF2 on myostatin promoter region and mechanisms underlying. In this study, we investigated the transcriptional regulation of MEF2 on porcine Mstn promoter activity in C2C12 cells. Sequence analysis of the 1 969 bp porcine Mstn promoter region revealed that it contained three potential MEF2 motifs. Using a serial deletion strategy, we tested the activity of several promoter fragments by luciferase assay. Overexpression of MEF2C, but not MEF2A increased Mstn promoter activity in all the promoter fragments with MEF2 motifs by two to six folds, in both C2C12 myoblasts and myotubes. When we transfected exogenous MEF2C, Mstn mRNA level was also upregulated in C2C12 cells, but the protein level was only significantly increased in myotubes. Thus, we propose that MEF2C could modulate and restrain myogenesis by Mstn activation and Mstn-dependent gene processing in porcine. Our research also provided potential targets and an effective molecule to regulate Mstn expression and gave a new way to explore the functional performance of Mstn.

  5. A combination of biomolecules enhances expression of E-cadherin and peroxisome proliferator-activated receptor gene leading to increased cell proliferation in primary human meniscal cells: an in vitro study.

    PubMed

    Pillai, Mamatha M; Elakkiya, V; Gopinathan, J; Sabarinath, C; Shanthakumari, S; Sahanand, K Santosh; Dinakar Rai, B K; Bhattacharyya, Amitava; Selvakumar, R

    2016-10-01

    The present study investigates the impact of biomolecules (biotin, glucose, chondroitin sulphate, proline) as supplement, (individual and in combination) on primary human meniscus cell proliferation. Primary human meniscus cells isolated from patients undergoing meniscectomy were maintained in Dulbecco's Modified Eagle's Medium (DMEM). The isolated cells were treated with above mentioned biomolecules as individual (0-100 µg/ml) and in combinations, as a supplement to DMEM. Based on the individual biomolecule study, a unique combination of biomolecules (UCM) was finalized using one way ANOVA analysis. With the addition of UCM as supplement to DMEM, meniscal cells reached 100 % confluency within 4 days in 60 mm culture plate; whereas the cells in medium devoid of UCM, required 36 days for reaching confluency. The impact of UCM on cell viability, doubling time, histology, gene expression, biomarkers expression, extra cellular matrix synthesis, meniscus cell proliferation with respect to passages and donor's age were investigated. The gene expression studies for E-cadherin and peroxisome proliferator-activated receptor (PPAR∆) using RT-qPCR and immunohistochemical analysis for Ki67, CD34 and Vimentin confirmed that UCM has significant impact on cell proliferation. The extracellular collagen and glycosaminoglycan secretion in cells supplemented with UCM were found to increase by 31 and 37 fold respectively, when compared to control on the 4th day. The cell doubling time was reduced significantly when supplemented with UCM. The addition of UCM showed positive influence on different passages and age groups. Hence, this optimized UCM can be used as an effective supplement for meniscal tissue engineering.

  6. Photo-initiated grafting of gelatin/N-maleic acyl-chitosan to enhance endothelial cell adhesion, proliferation and function on PLA surface.

    PubMed

    Zhu, Aiping; Zhao, Feng; Ma, Teng

    2009-07-01

    Vascular graft surface properties significantly affect adhesion, growth and function of endothelial cells (ECs). The bulk degradation property of poly(lactic acid) (PLA) makes it possible for it to be replaced by cellular materials and PLA is desirable as a scaffold material for vascular grafts. However, PLA has an unfavorable surface property for EC adhesion and proliferation due to the lack of a selective cell adhesion motif. Photo-initiated surface-grafting polymerization is a promising method for immobilizing certain biomacromolecules on material surfaces without compromising bulk properties. N-Maleic acyl-chitosan (NMCS) is a novel biocompatible amphiphilic derivative of chitosan with double bonds and can be initiated by ultraviolet light. In this study, gelatin was complexed with NMCS via hydrophobic interaction, and gel/NMCS complex thus formed was then grafted on the PLA surface to improve EC biocompatibility. X-ray photoelectron and Fourier transform infrared spectroscopy, and water contact angle measurement confirmed immobilization of the gel/NMCS complex on PLA surface. Moreover, the gel/NMCS modified PLA enhanced human umbilical vein endothelial cell (HUVEC) spreading and flattening, and promoted the expression of more structured CD31 and vWF compared to unmodified PLA film. Compared to the unmodified PLA surface, the HUVECs on the modified PLA surface had elevated uptake of acetylated low-density lipoprotein, and maintained the ability to modulate metabolic activity upon exposure to shear stress at 5dyncm(-2) by up-regulating nitric oxide and prostacyclin production. Cell retention was 1.6 times higher on the gel/NMCS-PLA surface, demonstrating its improved potential for hemocompatibility. These results indicate that photo-initiated surface-grafting of the biomimetic gel/NMCS complex is an effective method to modify material surfaces as vascular grafts.

  7. Engineering an improved cell cycle-regulatable herpes simplex virus type 1 amplicon vector with enhanced transgene expression in proliferating cells yet attenuated activities in resting cells.

    PubMed

    Wang, Grace Y; Ho, Ivy A W; Sia, Kian C; Miao, L; Hui, Kam M; Lam, Paula Y P

    2007-03-01

    We previously generated a herpes simplex virus type 1 (HSV-1)-based amplicon vector (denoted pC8-36) in which gene expression from the minimal cyclin A promoter is repressed by preventing the binding of a trans-activating protein, Gal4-NF-YA, to it through selective interaction with the transcriptional repressor protein CDF-1. Because CDF-1 is absent in actively dividing cells, transgene expression conferred by the pC8-36 vector is therefore cell cycle dependent. As gene therapy evolves to become a promising therapeutic modality for many human diseases, there is an increasing need to further improve the kinetics of gene regulation. In the present study, we examined whether the availability of more binding sites for CDF-1 repressor proteins could enhance transgene expression. Using an overlap extension polymerase chain reaction (PCR) method, the CDE and CHR elements within the minimum cyclin A promoter were multimerized to contain two, three, and six copies of the designated CDE/CHR sequence. Interestingly, our results demonstrated that six-copy CDE/CHR sequence motifs (pC8-6CC-Luc) conferred an approximately 20-fold increase in the ratio of cell cycle regulation compared with the previous reported construct. Further, the overall transcriptional activities mediated by pC8-6CC-Luc were stronger compared with the native human survivin promoter, which consists of three copies of the CDE element and one copy of the CHR element. pC8-6CC-Luc contained, in essence, only the synthetic six-copy CDE/CHR sequence motif (about 262 bp). In comparison with other native endogenous promoters, which usually contain many other transcription binding sites, pC8-6CC-Luc amplicon vectors should confer better regulated and consistent transgene expression and may be considered a gene delivery vector of choice to target actively proliferating tumor cells.

  8. Inhibition of tumor necrosis factor-alpha-induced interleukin-6 expression by telmisartan through cross-talk of peroxisome proliferator-activated receptor-gamma with nuclear factor kappaB and CCAAT/enhancer-binding protein-beta.

    PubMed

    Tian, Qingping; Miyazaki, Ryohei; Ichiki, Toshihiro; Imayama, Ikuyo; Inanaga, Keita; Ohtsubo, Hideki; Yano, Kotaro; Takeda, Kotaro; Sunagawa, Kenji

    2009-05-01

    Telmisartan, an angiotensin II type 1 receptor antagonist, was reported to be a partial agonist of peroxisome proliferator-activated receptor-gamma. Although peroxisome proliferator-activated receptor-gamma activators have been shown to have an anti-inflammatory effect, such as inhibition of cytokine production, it has not been determined whether telmisartan has such effects. We examined whether telmisartan inhibits expression of interleukin-6 (IL-6), a proinflammatory cytokine, in vascular smooth muscle cells. Telmisartan, but not valsartan, attenuated IL-6 mRNA expression induced by tumor necrosis factor-alpha (TNF-alpha). Telmisartan decreased TNF-alpha-induced IL-6 mRNA and protein expression in a dose-dependent manner. Because suppression of IL-6 mRNA expression was prevented by pretreatment with GW9662, a specific peroxisome proliferator-activated receptor-gamma antagonist, peroxisome proliferator-activated receptor-gamma may be involved in the process. Telmisartan suppressed IL-6 gene promoter activity induced by TNF-alpha. Deletion analysis suggested that the DNA segment between -150 bp and -27 bp of the IL-6 gene promoter that contains nuclear factor kappaB and CCAAT/enhancer-binding protein-beta sites was responsible for telmisartan suppression. Telmisartan attenuated TNF-alpha-induced nuclear factor kappaB- and CCAAT/enhancer-binding protein-beta-dependent gene transcription and DNA binding. Telmisartan also attenuated serum IL-6 level in TNF-alpha-infused mice and IL-6 production from rat aorta stimulated with TNF-alpha ex vivo. These data suggest that telmisartan may attenuate inflammatory process induced by TNF-alpha in addition to the blockade of angiotensin II type 1 receptor. Because both TNF-alpha and angiotensin II play important roles in atherogenesis through enhancement of vascular inflammation, telmisartan may be beneficial for treatment of not only hypertension but also vascular inflammatory change.

  9. Enhancing remote surveillance and assessment capabilities in support of non-proliferation using agricultural targets. Annual progress report, September 14, 1995--December 31, 1997

    SciTech Connect

    Perry, E.

    1997-09-01

    This report describes the Department of Energy`s Airborne Multisensor Pod System (ANIPS) missions which include agricultural targets to improve which include agricultural targets. The emphasis is on the use of these agricultural targets to improve nuclear non-proliferation assessment capability. Three areas of application of agricultural targets to non-proliferation is introduced: extending vegetation monitoring capability with radar, assessment of soil and crop damage using data fusion, and the use of data fusion for improved plant stress monitoring using hyperspectral data. Also, new algorithm development and future AMPS mission needs are discussed.

  10. The fibroblast growth factor-2 arrests Mycobacterium avium sp. paratuberculosis growth and immunomodulates host response in macrophages.

    PubMed

    Wang, Jianjun; Wang, Zeyou; Yao, Yongliang; Wu, Jianhong; Tang, Xin; Gu, Tao; Li, Guangxin

    2015-07-01

    Mycobacterium tuberculosisis (M. tb) epidemic is one of the most severe health problem worldwide, while mechanisms underlying its pathogenesis and host immune responses remain unclear. Mycobacterium avium (M. avium), a mycobacterial species related to M. tb, shares similarities with M. tb in many ways. In this study, using M. avium infection of macrophages as a model, we systematically studied the effect of fibroblast growth factor-2 (FGF-2) on M. avium infection of macrophages. Our results showed that M. avium infection could increase FGF-2 expression on both mRNA and protein levels. M. avium infection elevated TNF-α and IFN-γ production while the addition of FGF-2 could further increase TNF-α but not IFN-γ level. M. avium infection could increase the expression of oxygen/nitrogen metabolism proteins iNOS and SOD-1, and FGF-2 had additive effect on the expression of these two proteins. M. avium infection had inhibitive effect on actin expression while FGF-2 could partly counteract such inhibition. Moreover, FGF-2 could inhibit M. avium proliferation in macrophages. Our results together indicate that macrophage-secreted FGF-2 upon M. avium infection could suppress M. avium proliferation through various ways including cytokine production, enhancement of phagocytosis as well as oxygen/nitrogen metabolism.

  11. Long-term insulin-like growth factor-I expression in skeletal muscles attenuates the enhanced in vitro proliferation ability of the resident satellite cells in transgenic mice

    NASA Technical Reports Server (NTRS)

    Chakravarthy, M. V.; Fiorotto, M. L.; Schwartz, R. J.; Booth, F. W.

    2001-01-01

    Insulin-like growth factor-I (IGF-I) overexpression for 1-month in mouse skeletal muscle increases satellite cell proliferation potential. However, it is unknown whether this beneficial enhancement by IGF-I expression would persist over a longer-term duration in aged mice. This is an important issue to address if a prolonged course of IGF-I is to be used clinically in muscle-wasting conditions where satellite cells may become limiting. Using the IGF-I transgenic (IGF-I Tg) mouse that selectively expresses the IGF-I transgene in striated muscles, we found that 18-months of continuous IGF-I overexpression led to a loss in the enhanced in vitro proliferative capacity of satellite cells from Tg skeletal muscles. Also 18-month-old IGF-I Tg satellite cells lost the enhanced BrdU incorporation, greater pRb and Akt phosphorylations, and decreased p27(Kip1) levels initially observed in cells from 1-month-old IGF-I Tg mice. The levels of those biochemical markers reverted to similar values seen in the 18-months WT littermates. These findings, therefore, suggest that there is no further beneficial effect on enhancing satellite cell proliferation ability with persistent long-term expression of IGF-I in skeletal muscles of these transgenic mice.

  12. The 15N and 46R Residues of Highly Pathogenic Porcine Reproductive and Respiratory Syndrome Virus Nucleocapsid Protein Enhance Regulatory T Lymphocytes Proliferation

    PubMed Central

    Bai, Juan; Li, Yufeng; Zhang, Qiaoya; Jiang, Ping

    2015-01-01

    Porcine reproductive and respiratory syndrome virus (PRRSV) negatively modulates host immune responses, resulting in persistent infection and immunosuppression. PRRSV infection increases the number of PRRSV-specific regulatory T lymphocytes (Tregs) in infected pigs. However, the target antigens for Tregs proliferation in PRRSV infection have not been fully understood. In this study, we demonstrated that the highly pathogenic PRRSV (HP-PRRSV) induced more CD4+CD25+Foxp3+ Tregs than classical PRRSV (C-PRRSV) strain. Of the recombinant GP5, M and N proteins of HP-PRRSV expressed in baculovirus expression systems, only N protein induced Tregs proliferation. The Tregs assays showed that three amino-acid regions, 15–21, 42–48 and 88–94, in N protein played an important role in induction of Tregs proliferation with synthetic peptides covering the whole length of N protein. By using reverse genetic methods, it was firstly found that the 15N and 46R residues in PRRSV N protein were critical for induction of Tregs proliferation. The phenotype of induced Tregs closely resembled that of transforming-growth-factor-β-secreting T helper 3 Tregs in swine. These data should be useful for understanding the mechanism of immunity to PRRSV and development of infection control strategies in the future. PMID:26397116

  13. Proliferation of progeria cells is enhanced by lamina-associated polypeptide 2α (LAP2α) through expression of extracellular matrix proteins.

    PubMed

    Vidak, Sandra; Kubben, Nard; Dechat, Thomas; Foisner, Roland

    2015-10-01

    Lamina-associated polypeptide 2α (LAP2α) localizes throughout the nucleoplasm and interacts with the fraction of lamins A/C that is not associated with the peripheral nuclear lamina. The LAP2α-lamin A/C complex negatively affects cell proliferation. Lamins A/C are encoded by LMNA, a single heterozygous mutation of which causes Hutchinson-Gilford progeria syndrome (HGPS). This mutation generates the lamin A variant progerin, which we show here leads to loss of LAP2α and nucleoplasmic lamins A/C, impaired proliferation, and down-regulation of extracellular matrix components. Surprisingly, contrary to wild-type cells, ectopic expression of LAP2α in cells expressing progerin restores proliferation and extracellular matrix expression but not the levels of nucleoplasmic lamins A/C. We conclude that, in addition to its cell cycle-inhibiting function with lamins A/C, LAP2α can also regulate extracellular matrix components independently of lamins A/C, which may help explain the proliferation-promoting function of LAP2α in cells expressing progerin.

  14. Fibrillar Type I Collagen Enhances the Differentiation and Proliferation of Myofibroblasts by Lowering α2β1 Integrin Expression in Cardiac Fibrosis

    PubMed Central

    Hong, Jian; Chu, Ming; Qian, Lijun; Wang, Junhong; Guo, Yan

    2017-01-01

    Many studies have shown that α2β1 integrin plays an important role in the development of cardiac fibrosis. However, the mechanism of how α2β1 integrin regulates the differentiation and proliferation of myofibroblasts in cardiac fibrosis through fibrillar collagen (FC) remains uncertain. We established that FC mimicked the 3-dimensional extracellular matrix (ECM) of fibroblasts from post-myocardial infarction (MI) patients in vivo. This allowed us to explore the differentiation and proliferation of cardiac fibroblasts on FC. Here, we report that low expression of α2β1 integrin increased protein kinase B (AKT) activation and α-smooth muscle actin (α-SMA) expression. This occurred due to the instability of phosphatase and tensin homolog (PTEN) in myofibroblasts on FC. We also demonstrated that FC reduced protein phosphatase type 2A (PP2A) activity of myofibroblasts, which was coincident with low α2β1 integrin expression and activation of AKT, but not mitogen-activated protein kinase (ERK). In addition, knock-down of both β1 integrin and PP2A in fibroblasts promoted differentiation and proliferation via AKT activation and increased α-SMA expression. In summary, our study demonstrated that low α2β1 integrin expression regulated its downstream targets PTEN and AKT via crosstalk with PP2A, a critical cell signaling pathway that permits aberrant differentiation and proliferation of myofibroblasts on FC. PMID:28251149

  15. Methamphetamine oxidative stress, neurotoxicity, and functional deficits are modulated by nuclear factor-E2-related factor 2.

    PubMed

    Ramkissoon, Annmarie; Wells, Peter G

    2015-12-01

    Activation of redox-sensitive transcription factors like nuclear factor-E2-related factor 2 (Nrf2) can enhance the transcription of cytoprotective genes during oxidative stress. We investigated whether Nrf2 is activated by methamphetamine (METH) thereby altering neurotoxicity in Nrf2 +/+ and -/- adult mouse brain. A single dose of METH can induce the mRNA levels of Nrf2-regulated antioxidant and cytoprotective proteins in mouse brain. Multiple-day dosing with METH enhanced DNA oxidation and decreased tyrosine hydroxylase and dopamine transporter staining in the striatum, indicating dopaminergic nerve terminal toxicity, which was more severe in -/- mice, as were deficits in motor coordination and olfactory discrimination. These Nrf2-dependent effects were independent of changes in METH metabolism or the induction of hyperthermia. Similarly, METH increased striatal glial fibrillary acidic protein, indicating neurotoxicity. METH neurotoxicity was also observed in the glial cells and in the GABAergic system of the olfactory bulbs and was enhanced in -/- mice, whereas dopaminergic parameters were unaffected. With one-day dosing of METH, there were no differences between +/+ and -/- mice in either basal or METH-enhanced DNA oxidation and neurotoxicity markers. Nrf2-mediated pathways accordingly may protect against the neurodegenerative effects and functional deficits initiated by METH and perhaps other reactive oxygen species-enhancing neurotoxicants, when there is time for transcriptional activation and protein induction. In human users of METH, this mechanism may be essential when differences in drug abuse patterns may alter the induction and duration of Nrf2 activation thereby modulating susceptibility to the neurotoxic effects of METH.

  16. IL-2 enhances cervical cancer cells proliferation and JAK3/STAT5 phosphorylation at low doses, while at high doses IL-2 has opposite effects.

    PubMed

    Valle-Mendiola, Arturo; Weiss-Steider, Benny; Rocha-Zavaleta, Leticia; Soto-Cruz, Isabel

    2014-05-01

    The IL-2R signaling is critical for normal lymphocyte proliferation. However, the role of the IL-2 signaling in cervical cancer is not yet fully understood. We show that in IL-2R-expressing cervical cancer cells, JAK1 molecules are not phosphorylated. At low doses of IL-2, the constitutive phosphorylation of JAK3 and STAT5 increases in the tumor cells and decreases in lymphocytes, whereas the opposite occurs at high doses of IL-2. Using AG-490, the activation of JAK3 and the proliferation of cervical cancer cells were inhibited. We describe differences in the response of molecules downstream the IL-2R in lymphocytes and tumor cells.

  17. Propiconazole-enhanced hepatic cell proliferation is associated with dysregulation of the cholesterol biosynthesis pathway leading to activation of Erk1/2 through Ras farnesylation

    SciTech Connect

    Murphy, Lynea A.; Moore, Tanya; Nesnow, Stephen

    2012-04-15

    Propiconazole is a mouse hepatotumorigenic fungicide designed to inhibit CYP51, a key enzyme in the biosynthesis of ergosterol in fungi and is widely used in agriculture to prevent fungal growth. Metabolomic studies in mice revealed that propiconazole increased levels of hepatic cholesterol metabolites and bile acids, and transcriptomic studies revealed that genes within the cholesterol biosynthesis, cholesterol metabolism and bile acid biosyntheses pathways were up-regulated. Hepatic cell proliferation was also increased by propiconazole. AML12 immortalized hepatocytes were used to study propiconazole's effects on cell proliferation focusing on the dysregulation of cholesterol biosynthesis and resulting effects on Ras farnesylation and Erk1/2 activation as a primary pathway. Mevalonate, a key intermediate in the cholesterol biosynthesis pathway, increases cell proliferation in several cancer cell lines and tumors in vivo and serves as the precursor for isoprenoids (e.g. farnesyl pyrophosphate) which are crucial in the farnesylation of the Ras protein by farnesyl transferase. Farnesylation targets Ras to the cell membrane where it is involved in signal transduction, including the mitogen-activated protein kinase (MAPK) pathway. In our studies, mevalonic acid lactone (MVAL), a source of mevalonic acid, increased cell proliferation in AML12 cells which was reduced by farnesyl transferase inhibitors (L-744,832 or manumycin) or simvastatin, an HMG-CoA reductase inhibitor, indicating that this cell system responded to alterations in the cholesterol biosynthesis pathway. Cell proliferation in AML12 cells was increased by propiconazole which was reversed by co-incubation with L-744,832 or simvastatin. Increasing concentrations of exogenous cholesterol muted the proliferative effects of propiconazole and the inhibitory effects of L-733,832, results ascribed to reduced stimulation of the endogenous cholesterol biosynthesis pathway. Western blot analysis of subcellular

  18. Postnatal treadmill exercise alleviates short-term memory impairment by enhancing cell proliferation and suppressing apoptosis in the hippocampus of rat pups born to diabetic rats.

    PubMed

    Kim, Young Hoon; Sung, Yun-Hee; Lee, Hee-Hyuk; Ko, Il-Gyu; Kim, Sung-Eun; Shin, Mal-Soon; Kim, Bo-Kyun

    2014-08-01

    During pregnancy, diabetes mellitus exerts detrimental effects on the development of the fetus, especially the central nervous system. In the current study, we evaluated the effects of postnatal treadmill exercise on short-term memory in relation with cell proliferation and apoptosis in the hippocampus of rat pups born to streptozotocin (STZ)-induced diabetic maternal rats. Adult female rats were mated with male rats for 24 h. Two weeks after mating, the pregnant female rats were divided into two groups: control group and STZ injection group. The pregnant rats in the STZ injection group were administered 40 mg/kg of STZ intraperitoneally. After birth, the rat pups were divided into the following four groups: control group, control with postnatal exercise group, maternal STZ-injection group, and maternal STZ-injection with postnatal exercise group. The rat pups in the postnatal exercise groups were made to run on a treadmill for 30 min once a day, 5 times per week for 2 weeks beginning 4 weeks after birth. The rat pups born to diabetic rats were shown to have short-term memory impairment with suppressed cell proliferation and increased apoptosis in the hippocampal dentate gyrus. Postnatal treadmill exercise alleviated short-term memory impairment by increased cell proliferation and suppressed apoptosis in the rat pups born to diabetic rats. These findings indicate that postnatal treadmill exercise may be used as a valuable strategy to ameliorate neurodevelopmental problems in children born to diabetics.

  19. New Horizons in Enhancing the Proliferation and Differentiation of Neural Stem Cells Using Stimulatory Effects of the Short Time Exposure to Radiofrequency Radiation.

    PubMed

    Eghlidospour, M; Mortazavi, S M J; Yousefi, F; Mortazavi, S A R

    2015-09-01

    Mobile phone use and wireless communication technology have grown explosively over the past decades. This rapid growth has caused widespread global concern about the potential detrimental effects of this technology on human health. Stem cells generate specialized cell types of the tissue in which they reside through normal differentiation pathways. Considering the undeniable importance of stem cells in modern medicine, numerous studies have been performed on the effects of ionizing and non-ionizing radiation on cellular processes such as: proliferation, differentiation, cell cycle and DNA repair processes. We have conducted extensive studies on beneficial (stimulatory) or detrimental biological effects of exposure to different sources of electromagnetic fields such as mobile phones, mobile phone base stations, mobile phone jammers, radar systems, magnetic resonance imaging (MRI) systems and dentistry cavitrons over the past years. In this article, recent studies on the biological effects of non-ionizing electromagnetic radiation in the range of radiofrequency (RF) on some important features of stem cells such as their proliferation and differentiation are reviewed. Studies reviewed in this paper indicate that the stimulatory or inhibitory effects of RF radiation on the proliferation and differentiation of stem cells depend on various factors such as the biological systems, experiment conditions, the frequency and intensity of RF and the duration of exposure.

  20. New Horizons in Enhancing the Proliferation and Differentiation of Neural Stem Cells Using Stimulatory Effects of the Short Time Exposure to Radiofrequency Radiation

    PubMed Central

    Eghlidospour, M.; Mortazavi, S. M. J.; Yousefi, F.; Mortazavi, S. A. R.

    2015-01-01

    Mobile phone use and wireless communication technology have grown explosively over the past decades. This rapid growth has caused widespread global concern about the potential detrimental effects of this technology on human health. Stem cells generate specialized cell types of the tissue in which they reside through normal differentiation pathways. Considering the undeniable importance of stem cells in modern medicine, numerous studies have been performed on the effects of ionizing and non-ionizing radiation on cellular processes such as: proliferation, differentiation, cell cycle and DNA repair processes. We have conducted extensive studies on beneficial (stimulatory) or detrimental biological effects of exposure to different sources of electromagnetic fields such as mobile phones, mobile phone base stations, mobile phone jammers, radar systems, magnetic resonance imaging (MRI) systems and dentistry cavitrons over the past years. In this article, recent studies on the biological effects of non-ionizing electromagnetic radiation in the range of radiofrequency (RF) on some important features of stem cells such as their proliferation and differentiation are reviewed. Studies reviewed in this paper indicate that the stimulatory or inhibitory effects of RF radiation on the proliferation and differentiation of stem cells depend on various factors such as the biological systems, experiment conditions, the frequency and intensity of RF and the duration of exposure. PMID:26396965

  1. The PIKfyve–ArPIKfyve–Sac3 triad in human breast cancer: Functional link between elevated Sac3 phosphatase and enhanced proliferation of triple negative cell lines

    SciTech Connect

    Ikonomov, Ognian C. Filios, Catherine Sbrissa, Diego Chen, Xuequn Shisheva, Assia

    2013-10-18

    Highlights: •We assess PAS complex proteins and phosphoinositide levels in breast cancer cells. •Sac3 and ArPIKfyve are markedly elevated in triple-negative breast cancer cells. •Sac3 silencing inhibits proliferation in triple-negative breast cancer cell lines. •Phosphoinositide profiles are altered in breast cancer cells. •This is the first evidence linking high Sac3 with breast cancer cell proliferation. -- Abstract: The phosphoinositide 5-kinase PIKfyve and 5-phosphatase Sac3 are scaffolded by ArPIKfyve in the PIKfyve–ArPIKfyve–Sac3 (PAS) regulatory complex to trigger a unique loop of PtdIns3P–PtdIns(3,5)P{sub 2} synthesis and turnover. Whereas the metabolizing enzymes of the other 3-phosphoinositides have already been implicated in breast cancer, the role of the PAS proteins and the PtdIns3P–PtdIns(3,5)P{sub 2} conversion is unknown. To begin elucidating their roles, in this study we monitored the endogenous levels of the PAS complex proteins in cell lines derived from hormone-receptor positive (MCF7 and T47D) or triple-negative breast cancers (TNBC) (BT20, BT549 and MDA-MB-231) as well as in MCF10A cells derived from non-tumorigenic mastectomy. We report profound upregulation of Sac3 and ArPIKfyve in the triple negative vs. hormone-sensitive breast cancer or non-tumorigenic cells, with BT cell lines showing the highest levels. siRNA-mediated knockdown of Sac3, but not that of PIKfyve, significantly inhibited proliferation of BT20 and BT549 cells. In these cells, knockdown of ArPIKfyve had only a minor effect, consistent with a primary role for Sac3 in TNBC cell proliferation. Intriguingly, steady-state levels of PtdIns(3,5)P{sub 2} in BT20 and T47D cells were similar despite the 6-fold difference in Sac3 levels between these cell lines. However, steady-state levels of PtdIns3P and PtdIns5P, both regulated by the PAS complex, were significantly reduced in BT20 vs. T47D or MCF10A cell lines, consistent with elevated Sac3 affecting directly or

  2. CCAAT/enhancer-binding protein alpha (C/EBP alpha) inhibits cell proliferation through the p21 (WAF-1/CIP-1/SDI-1) protein.

    PubMed

    Timchenko, N A; Wilde, M; Nakanishi, M; Smith, J R; Darlington, G J

    1996-04-01

    C/EBPalpha has a role in growth arrest and differentiation of mouse preadipocytes. To study the mechanism of C/EBPalpha-induced growth arrest, we developed a cell line, HT1, that contained the human C/EBPalpha gene under Lac repressor control. IPTG-induced C/EBPalpha caused inhibition of cell proliferation and DNA synthesis as measured by colony growth assays, cell counting, and BrdU uptake. A number of proteins that are known to be involved in the regulation of the cell cycle, such as cyclin-dependent kinase (CDK)2 and CDK4, proliferating cell nuclear antigen (PCNA), p53, c-fos, and the CDK inhibitor p16 and p27 were investigated by Western analysis. No change in their expression was observed. However, the p21 (WAF-1/CIP-1/SDI-1) protein was significantly elevated in growth-arrested HT1 cells. Elevation of p21/SDI-1 mRNA (threefold) and activation of the p21/SDI-1 promoter by C/EBPalpha did not account for the 12- to 20-fold increase in p21/SDI-1 protein. Protein synthesis inhibition by cycloheximide (CHX) treatment indicated that the half-life of p21/SDI-1 in dividing HT1 cells was approximately 30 min. However, in C/EBPalpha growth-arrested cells, the level of the p21/SDI-1 did not change for > 80 min after CHX addition. Our studies demonstrate that C/EBPalpha activates p21/SDI-1 by increasing p21/SDI-1 gene expression and by post-translational stabilization of p21/SDI-1 protein. Furthermore, induction of p21/SDI-1 is responsible for the ability of C/EBPalpha to inhibit proliferation because transcription of antisense p21/SDI-1 mRNA eliminated growth inhibition by C/EBPalpha.

  3. Overexpression of miR-18a negatively regulates myocyte enhancer factor 2D to increase the permeability of the blood-tumor barrier via Krüppel-like factor 4-mediated downregulation of zonula occluden-1, claudin-5, and occludin.

    PubMed

    Zhao, Ying-Yu; Zhao, Li-Ni; Wang, Ping; Miao, Yin-Sha; Liu, Yun-Hui; Wang, Zhen-Hua; Ma, Jun; Li, Zhen; Li, Zhi-Qing; Xue, Yi-Xue

    2015-12-01

    miR-18a represses angiogenesis and tumor evasion by weakening vascular endothelial growth factor and transforming growth factor-β signaling to prolong the survival of glioma patients, although it is thought to be an oncogene. This study investigates the potential effects of miR-18a on the permeability of the blood-tumor barrier (BTB) and its possible molecular mechanisms. An in vitro BTB model was successfully established. The endogenous expression of miR-18a in glioma vascular endothelial cells (GECs) was significantly lower than that in normal vascular ECs, and the overexpression of miR-18a significantly increased the permeability of the BTB as well as downregulating the mRNA and protein expressions of tight junction-related proteins zonula occluden-1 (ZO-1), claudin-5, and occludin in GECs. Dual luciferase reporter assays revealed that miR-18a bound to the 3'-untranslated region (3'UTR) of myocyte enhancer factor 2D (MEF2D). The overexpression of both miR-18a and MEF2D with the 3'UTR significantly weakened the effect caused by miR-18a of decreasing the mRNA and protein expressions of ZO-1, claudin-5 and occludin and of increasing the permeability of the BTB. Chromatin immunoprecipitation showed that MEF2D could directly bind to KLF4 promoter. This study shows that miR-18a targets and negatively regulates MEF2D, which further regulates tight junction-related proteins ZO-1, claudin-5, and occludin through transactivation of KLF4 and, finally, changes the permeability of the BTB. MiR-18a should garner growing attention because it might serve as a potential target in opening the BTB and providing a new strategy for the treatment of gliomas.

  4. Serum-free isolation and culture system to enhance the proliferation and bone regeneration of adipose tissue-derived mesenchymal stem cells.

    PubMed

    Sato, Kazutoshi; Itoh, Takehiro; Kato, Toshiki; Kitamura, Yukiko; Kaul, Sunil C; Wadhwa, Renu; Sato, Fujio; Ohneda, Osamu

    2015-05-01

    Cell therapy using human mesenchymal stem cells (MSCs) is an attractive approach for many refractory diseases. Adipose tissue-derived mesenchymal stem cells (AT-MSCs) are considered as a favorable tool due to its abundance in the body, easy proliferation, and high cytokine production potency. In order to avoid the risks associated with the use of fetal bovine serum (FBS) in culture that includes batch variations and contamination with pathogens, development of serum-free culture system has been initiated. We have formulated a completely serum-free culture medium (SFM) that could be used not only for the expansion of AT-MSCs but also for initial isolation. We demonstrate that the AT-MSCs isolated and cultured in serum-free medium (AT-MSCs/SFM) possess high proliferation capacity and differentiation potency to osteoblast, adipocyte, and chondrocyte lineages in vitro. In in vivo bone fraction model analysis, AT-MSCs/SFM showed higher bone repair potency and quality of the regenerated bone than the cells cultured in serum-containing medium (AT-MSCs/SCM). This was attributed to the (i) presence of translated cells in the bone, as evidenced by in vivo imaging of the illuminated translated cells and (ii) high level of expression and induction capacity of AT-MSCs/SFM for cytokine BMP2, CCL2, and CCL5. Taken together, we report a new serum-free culture system for AT-MSCs that is suitable for cell therapy.

  5. Enriched Astaxanthin Extract from Haematococcus pluvialis Augments Growth Factor Secretions to Increase Cell Proliferation and Induces MMP1 Degradation to Enhance Collagen Production in Human Dermal Fibroblasts.

    PubMed

    Chou, Hsin-Yu; Lee, Chelsea; Pan, Jian-Liang; Wen, Zhi-Hong; Huang, Shu-Hung; Lan, Chi-Wei John; Liu, Wang-Ta; Hour, Tzyh-Chyuan; Hseu, You-Cheng; Hwang, Byeong Hee; Cheng, Kuo-Chen; Wang, Hui-Min David

    2016-06-16

    Among many antioxidants that are used for the repairing of oxidative stress induced skin damages, we identified the enriched astaxanthin extract (EAE) from Haematococcus pluvialis as a viable ingredient. EAE was extracted from the red microalgae through supercritical fluid carbon dioxide extraction. To compare the effectiveness, EAE wastreated on human dermal fibroblasts with other components, phorbol 12-myristate 13-acetate (PMA), and doxycycline. With sirius red staining and quantitative real-time polymerase chain reaction (qRT-PCR), we found that PMA decreased the collagen concentration and production while overall the addition of doxycycline and EAE increased the collagen concentration in a trial experiments. EAE increased collagen contents through inhibited MMP1 and MMP3 mRNA expression and induced TIMP1, the antagonists of MMPs protein, gene expression. As for when tested for various proteins through western blotting, it was seen that the addition of EAE increased the expression of certain proteins that promote cell proliferation. Testing those previous solutions using growth factor assay, it was noticeable that EAE had a positive impact on cell proliferation and vascular endothelial growth factor (VEGF) than doxycycline, indicating that it was a better alternative treatment for collagen production. To sum up, the data confirmed the possible applications as medical cosmetology agentsand food supplements.

  6. Enriched Astaxanthin Extract from Haematococcus pluvialis Augments Growth Factor Secretions to Increase Cell Proliferation and Induces MMP1 Degradation to Enhance Collagen Production in Human Dermal Fibroblasts

    PubMed Central

    Chou, Hsin-Yu; Lee, Chelsea; Pan, Jian-Liang; Wen, Zhi-Hong; Huang, Shu-Hung; Lan, Chi-Wei John; Liu, Wang-Ta; Hour, Tzyh-Chyuan; Hseu, You-Cheng; Hwang, Byeong Hee; Cheng, Kuo-Chen; Wang, Hui-Min David

    2016-01-01

    Among many antioxidants that are used for the repairing of oxidative stress induced skin damages, we identified the enriched astaxanthin extract (EAE) from Haematococcus pluvialis as a viable ingredient. EAE was extracted from the red microalgae through supercritical fluid carbon dioxide extraction. To compare the effectiveness, EAE wastreated on human dermal fibroblasts with other components, phorbol 12-myristate 13-acetate (PMA), and doxycycline. With sirius red staining and quantitative real-time polymerase chain reaction (qRT-PCR), we found that PMA decreased the collagen concentration and production while overall the addition of doxycycline and EAE increased the collagen concentration in a trial experiments. EAE increased collagen contents through inhibited MMP1 and MMP3 mRNA expression and induced TIMP1, the antagonists of MMPs protein, gene expression. As for when tested for various proteins through western blotting, it was seen that the addition of EAE increased the expression of certain proteins that promote cell proliferation. Testing those previous solutions using growth factor assay, it was noticeable that EAE had a positive impact on cell proliferation and vascular endothelial growth factor (VEGF) than doxycycline, indicating that it was a better alternative treatment for collagen production. To sum up, the data confirmed the possible applications as medical cosmetology agentsand food supplements. PMID:27322248

  7. Tobacco Translationally Controlled Tumor Protein Interacts with Ethylene Receptor Tobacco Histidine Kinase1 and Enhances Plant Growth through Promotion of Cell Proliferation1[OPEN

    PubMed Central

    Tao, Jian-Jun; Cao, Yang-Rong; Chen, Hao-Wei; Wei, Wei; Li, Qing-Tian; Ma, Biao; Zhang, Wan-Ke; Chen, Shou-Yi; Zhang, Jin-Song

    2015-01-01

    Ethylene is an important phytohormone in the regulation of plant growth, development, and stress response throughout the lifecycle. Previously, we discovered that a subfamily II ethylene receptor tobacco (Nicotiana tabacum) Histidine Kinase1 (NTHK1) promotes seedling growth. Here, we identified an NTHK1-interacting protein translationally controlled tumor protein (NtTCTP) by the yeast (Saccharomyces cerevisiae) two-hybrid assay and further characterized its roles in plant growth. The interaction was further confirmed by in vitro glutathione S-transferase pull down and in vivo coimmunoprecipitation and bimolecular fluorescence complementation assays, and the kinase domain of NTHK1 mediates the interaction with NtTCTP. The NtTCTP protein is induced by ethylene treatment and colocalizes with NTHK1 at the endoplasmic reticulum. Overexpression of NtTCTP or NTHK1 reduces plant response to ethylene and promotes seedling growth, mainly through acceleration of cell proliferation. Genetic analysis suggests that NtTCTP is required for the function of NTHK1. Furthermore, association of NtTCTP prevents NTHK1 from proteasome-mediated protein degradation. Our data suggest that plant growth inhibition triggered by ethylene is regulated by a unique feedback mechanism, in which ethylene-induced NtTCTP associates with and stabilizes ethylene receptor NTHK1 to reduce plant response to ethylene and promote plant growth through acceleration of cell proliferation. PMID:25941315

  8. Silencing of the Charcot-Marie-Tooth associated MTMR2 gene decreases proliferation and enhances cell death in primary cultures of Schwann cells.

    PubMed

    Chojnowski, Alexandre; Ravisé, Nicole; Bachelin, Corinne; Depienne, Christel; Ruberg, Merle; Brugg, Bernard; Laporte, Jocelyn; Baron-Van Evercooren, Anne; LeGuern, Eric

    2007-05-01

    Loss of function of the myotubularin (MTM)-related protein 2 (MTMR2) in Schwann cells causes Charcot-Marie-Tooth disease type 4B1, a severe demyelinating neuropathy, but the consequences of MTMR2 disruption in Schwann cells are unknown. We established the expression profile of MTMR2 by real-time RT-PCR during rat myelination and showed it to be preferentially expressed at the onset of the myelination period. We developed a model in which MTMR2 loss of function was reproduced in primary cultures of Schwann cells by RNA interference. We found that depletion of MTMR2 in Schwann cells decreased their rate of proliferation. Furthermore, when cultivated in serum-free medium, MTMR2 depletion increased the number of Schwann cells that died by a caspase-dependent process. These results support the hypothesis that loss of MTMR2 in patients, by decreasing Schwann cells proliferation and survival, may impair the first stages of myelination of the peripheral nervous system.

  9. Tobacco Translationally Controlled Tumor Protein Interacts with Ethylene Receptor Tobacco Histidine Kinase1 and Enhances Plant Growth through Promotion of Cell Proliferation.

    PubMed

    Tao, Jian-Jun; Cao, Yang-Rong; Chen, Hao-Wei; Wei, Wei; Li, Qing-Tian; Ma, Biao; Zhang, Wan-Ke; Chen, Shou-Yi; Zhang, Jin-Song

    2015-09-01

    Ethylene is an important phytohormone in the regulation of plant growth, development, and stress response throughout the lifecycle. Previously, we discovered that a subfamily II ethylene receptor tobacco (Nicotiana tabacum) Histidine Kinase1 (NTHK1) promotes seedling growth. Here, we identified an NTHK1-interacting protein translationally controlled tumor protein (NtTCTP) by the yeast (Saccharomyces cerevisiae) two-hybrid assay and further characterized its roles in plant growth. The interaction was further confirmed by in vitro glutathione S-transferase pull down and in vivo coimmunoprecipitation and bimolecular fluorescence complementation assays, and the kinase domain of NTHK1 mediates the interaction with NtTCTP. The NtTCTP protein is induced by ethylene treatment and colocalizes with NTHK1 at the endoplasmic reticulum. Overexpression of NtTCTP or NTHK1 reduces plant response to ethylene and promotes seedling growth, mainly through acceleration of cell proliferation. Genetic analysis suggests that NtTCTP is required for the function of NTHK1. Furthermore, association of NtTCTP prevents NTHK1 from proteasome-mediated protein degradation. Our data suggest that plant growth inhibition triggered by ethylene is regulated by a unique feedback mechanism, in which ethylene-induced NtTCTP associates with and stabilizes ethylene receptor NTHK1 to reduce plant response to ethylene and promote plant growth through acceleration of cell proliferation.

  10. Initiatives for proliferation prevention

    SciTech Connect

    1997-04-01

    Preventing the proliferation of weapons of mass destruction is a central part of US national security policy. A principal instrument of the Department of Energy`s (DOE`s) program for securing weapons of mass destruction technology and expertise and removing incentives for scientists, engineers and technicians in the newly independent states (NIS) of the former Soviet Union to go to rogue countries or assist terrorist groups is the Initiatives for Proliferation Prevention (IPP). IPP was initiated pursuant to the 1994 Foreign Operations Appropriations Act. IPP is a nonproliferation program with a commercialization strategy. IPP seeks to enhance US national security and to achieve nonproliferation objectives by engaging scientists, engineers and technicians from former NIS weapons institutes; redirecting their activities in cooperatively-developed, commercially viable non-weapons related projects. These projects lead to commercial and economic benefits for both the NIS and the US IPP projects are funded in Russian, Ukraine, Kazakhstan and Belarus. This booklet offers an overview of the IPP program as well as a sampling of some of the projects which are currently underway.

  11. Biodegradable Microcarriers of Poly(Lactide-co-Glycolide) and Nano-Hydroxyapatite Decorated with IGF-1 via Polydopamine Coating for Enhancing Cell Proliferation and Osteogenic Differentiation.

    PubMed

    Gao, Tianlin; Zhang, Ning; Wang, Zongliang; Wang, Yu; Liu, Ya; Ito, Yoshihiro; Zhang, Peibiao

    2015-08-01

    In this study, insulin-like growth factor 1 (IGF-1) was successfully immobilized on the poly(lactide-co-glycolide)/hydroxyapatite (PLGA/HA) and pure PLGA microcarriers via polydopamine (pDA). The results demonstrated that the pDA layer facilitated simple and highly efficient immobilization of peptides on the microcarriers within 20 min. Mouse adipose-derived stem cells (ADSCs) attachment and proliferation on IGF-1-immobilized microcarriers were much higher than non-immobilized ones. More importantly, the IGF-1-immobilized PLGA/HA microcarriers significantly increased alkaline phosphatase (ALP) activity and expression of osteogenesis-related genes of ADSCs. Therefore, it is considered that the IGF-1-decorated PLGA/HA microcarriers will be of great value in the bone tissue engineering.

  12. CYP1B1 Enhances Cell Proliferation and Metastasis through Induction of EMT and Activation of Wnt/β-Catenin Signaling via Sp1 Upregulation

    PubMed Central

    Kwon, Yeo-Jung; Baek, Hyoung-Seok; Ye, Dong-Jin; Shin, Sangyun; Kim, Donghak; Chun, Young-Jin

    2016-01-01

    Cytochrome P450 1B1 (CYP1B1) is a major E2 hydroxylase involved in the metabolism of potential carcinogens. CYP1B1 expression has been reported to be higher in tumors compared to normal tissues, especially in hormone-related cancers including breast, ovary, and prostate tumors. To explore the role of CYP1B1 in cancer progression, we investigated the action of CYP1B1 in cells with increased CYP1B1 via the inducer 7,12-dimethylbenz[α]anthracene (DMBA) or an overexpression vector, in addition to decreased CYP1B1 via the inhibitor tetramethoxystilbene (TMS) or siRNA knockdown. We observed that CYP1B1 promoted cell proliferation, migration, and invasion in MCF-7 and MCF-10A cells. To understand its molecular mechanism, we measured key oncogenic proteins including β-catenin, c-Myc, ZEB2, and matrix metalloproteinases following CYP1B1 modulation. CYP1B1 induced epithelial-mesenchymal transition (EMT) and activated Wnt/β-catenin signaling via upregulation of CTNNB1, ZEB2, SNAI1, and TWIST1. Sp1, a transcription factor involved in cell growth and metastasis, was positively regulated by CYP1B1, and suppression of Sp1 expression by siRNA or DNA binding activity using mithramycin A blocked oncogenic transformation by CYP1B1. Therefore, we suggest that Sp1 acts as a key mediator for CYP1B1 action. Treatment with 4-hydroxyestradiol (4-OHE2), a major metabolite generated by CYP1B1, showed similar effects as CYP1B1 overexpression, indicating that CYP1B1 activity mediated various oncogenic events in cells. In conclusion, our data suggests that CYP1B1 promotes cell proliferation and metastasis by inducing EMT and Wnt/β-catenin signaling via Sp1 induction. PMID:26981862

  13. CYP1B1 Enhances Cell Proliferation and Metastasis through Induction of EMT and Activation of Wnt/β-Catenin Signaling via Sp1 Upregulation.

    PubMed

    Kwon, Yeo-Jung; Baek, Hyoung-Seok; Ye, Dong-Jin; Shin, Sangyun; Kim, Donghak; Chun, Young-Jin

    2016-01-01

    Cytochrome P450 1B1 (CYP1B1) is a major E2 hydroxylase involved in the metabolism of potential carcinogens. CYP1B1 expression has been reported to be higher in tumors compared to normal tissues, especially in hormone-related cancers including breast, ovary, and prostate tumors. To explore the role of CYP1B1 in cancer progression, we investigated the action of CYP1B1 in cells with increased CYP1B1 via the inducer 7,12-dimethylbenz[α]anthracene (DMBA) or an overexpression vector, in addition to decreased CYP1B1 via the inhibitor tetramethoxystilbene (TMS) or siRNA knockdown. We observed that CYP1B1 promoted cell proliferation, migration, and invasion in MCF-7 and MCF-10A cells. To understand its molecular mechanism, we measured key oncogenic proteins including β-catenin, c-Myc, ZEB2, and matrix metalloproteinases following CYP1B1 modulation. CYP1B1 induced epithelial-mesenchymal transition (EMT) and activated Wnt/β-catenin signaling via upregulation of CTNNB1, ZEB2, SNAI1, and TWIST1. Sp1, a transcription factor involved in cell growth and metastasis, was positively regulated by CYP1B1, and suppression of Sp1 expression by siRNA or DNA binding activity using mithramycin A blocked oncogenic transformation by CYP1B1. Therefore, we suggest that Sp1 acts as a key mediator for CYP1B1 action. Treatment with 4-hydroxyestradiol (4-OHE2), a major metabolite generated by CYP1B1, showed similar effects as CYP1B1 overexpression, indicating that CYP1B1 activity mediated various oncogenic events in cells. In conclusion, our data suggests that CYP1B1 promotes cell proliferation and metastasis by inducing EMT and Wnt/β-catenin signaling via Sp1 induction.

  14. Orexin A upregulates the protein expression of OX1R and enhances the proliferation of SGC-7901 gastric cancer cells through the ERK signaling pathway.

    PubMed

    Liu, Yuanyuan; Zhao, Yuyan; Ju, Shujing; Guo, Lei

    2015-02-01

    Orexins are hypothalamic peptides that regulate food intake, wakefulness, the reward system and energy metabolism. Recent studies have demonstrated the ability of orexins to promote a robust apoptosis and subsequent inhibition of cell growth in various types of cancer cells. The present study was conducted to investigate the effects of orexin A on the survival of human gastric cancer cells, SGC‑7901, and the possible mechanisms. SGC‑7901 cells were exposed to various concentrations of orexin A in vitro in the presence or absence of the orexin receptor 1 (OX1R) antagonist (SB334867), extracellular signal‑regulated kinases 1 and 2 (ERK1/2) antagonist (U0126) or a combination of the two antagonists. The amount of cell proliferation, viability and apoptosis, caspase‑8 and caspases‑9 activities, OX1R protein expression and ERK1/2 protein levels were determined. The expression of OX1R in SGC‑7901 cells was observed. Orexin A (10-10 to 10-6 M) stimulated SGC‑7901 cell proliferation and viability, reduced the pro‑apoptotic activity of caspase‑9 and protected the cells from apoptosis in a dose‑dependent manner. Additionally, ERK1/2 phosphorylation was stimulated by orexin A (10-10 to 10-6 M). However, the OX1R antagonist SB334867 (10-6 M), ERK1/2 antagonist U0126 (30 µM) or the combination of antagonists blocked the effects of orexin A to a certain extent. These results suggest that stimulation of OX1R induces the growth of SGC‑7901 gastric cancer cells through activation of ERK1/2 signaling pathway. These findings add a new dimension to the biological activities of orexin, which may have important implications in health and disease, in particular gastric cancer.

  15. Upregulation of microRNA-524-5p enhances the cisplatin sensitivity of gastric cancer cells by modulating proliferation and metastasis via targeting SOX9

    PubMed Central

    Zhou, Jin; Sun, Qing; Liang, Hansi; Gao, Ling

    2017-01-01

    Cisplatin-based chemotherapy is the most commonly used treatment regimen for gastric cancer (GC), however, the resistance to cisplatin represents the key limitation for the therapeutic efficacy. Aberrant expression of MiR-524-5p appears to be involves in tumorigenesis and chemoresistance. However, the mechanism by which miR-524-5p mediates effects of cisplatin treatment in GC remains poorly understood. Expressions of MiR-524-5p was detected in GC tissues and cell lines by qRT-PCR. Cell proliferation was observed by MTT assay; Cell migration was detected by transwell migration and invasion assay. The targeting protein of miR-524-5p was identified by luciferase reporter assay and western blot. We found that downregulation of miR-524-5p in GC tissues and cell lines. SC-M1 and AZ521 cells resistant to cisplatin expressed low levels of miR-524-5p in comparison to the sensitive parental cells. Overexpression of miR-524-5p expression in SC-M1 and AZ521 cells inhibited cell proliferation, migration, and invasion, and conferred sensitivity to cisplatin-resistant GC cells. Subsequently, we identified SOX9 as a functional target protein of miR-524-5p and found that SOX9 overexpression could counteracts the chemosensitizing effects of miR-524-5p. These results provide novel insight into the regulation of GC tumorigenesis and progression by miRNAs. Restoration of miR-524-5p may have therapeutic potential against GC. PMID:27880941

  16. Inhibition of miR301 enhances Akt-mediated cell proliferation by accumulation of PTEN in nucleus and its effects on cell-cycle regulatory proteins

    PubMed Central

    Jain, Mayur V.; Shareef, Ahmad; Likus, Wirginia; Cieślar-Pobuda, Artur; Ghavami, Saeid; Łos, Marek J.

    2016-01-01

    Micro-RNAs (miRs) represent an innovative class of genes that act as regulators of gene expression. Recently, the aberrant expression of several miRs has been associated with different types of cancers. In this study, we show that miR301 inhibition influences PI3K-Akt pathway activity. Akt overexpression in MCF7 and MDAMB468 cells caused downregulation of miR301 expression. This effect was confirmed by co-transfection of miR301-modulators in the presence of Akt. Cells overexpressing miR301-inhibitor and Akt, exhibited increased migration and proliferation. Experimental results also confirmed PI3K, PTEN and FoxF2 as regulatory targets for miR301. Furthermore, Akt expression in conjunction with miR301-inhibitor increased nuclear accumulation of PTEN, thus preventing it from downregulating the PI3K-signalling. In summary, our data emphasize the importance of miR301 inhibition on PI3K-Akt pathway-mediated cellular functions. Hence, it opens new avenues for the development of new anti-cancer agents preferentially targeting PI3K-Akt pathway. PMID:26967567

  17. miR-143 inhibits bladder cancer cell proliferation and enhances their sensitivity to gemcitabine by repressing IGF-1R signaling

    PubMed Central

    Wang, Hengbing; Li, Qi; Niu, Xiaobing; Wang, Gongcheng; Zheng, Sinian; Fu, Guangbo; Wang, Zengjun

    2017-01-01

    microRNAs (miRNAs) are a class of small RNAs that regulate gene expression. It has been demonstrated that aberrant miRNA expression is associated with cancer development and carcinogenesis. Altered miRNA expression has been suggested to occur in bladder cancer. In other cancer systems, studies have indicated that miR-143, as a tumor suppressor gene, plays essential roles in cancer progression. However, its role in bladder cancer has yet to be elucidated. In the present study, we observed that miR-143 expression was downregulated in human bladder cancer tissues and cells, and that its levels were negatively correlated with bladder cancer clinical stages. We further demonstrated that insulin-like growth factor-1 receptor (IGF-1R) is a functional target of miR-143. Their expression levels were inversely correlated in bladder cancer samples. Overexpression of miR-143 inhibited cell proliferation and promoted chemosensitivity of bladder cancer 5637 cells to gemcitabine. Consistently, small interfering RNA-mediated knockdown of IGF-1R phenocopied miR-143 overexpression. Notably, the expression of IGF-1R is a predictor of patient prognosis. Collectively, our findings indicate that miR-143 is a valuable biomarker for bladder cancer. The miR-143/IGF-1R axis is associated with bladder cancer drug resistance and patient survival. PMID:28123579

  18. β1 integrin adhesion enhances IL-6 mediated STAT3 signaling in Myeloma cells: Implications for Microenvironment Influence on Tumor Survival and Proliferation

    PubMed Central

    Shain, Kenneth H.; Yarde, Danielle N.; Meads, Mark B.; Huang, Mei; Jove, Richard; Hazlehurst, Lori A.; Dalton, William S.

    2009-01-01

    The bone marrow microenvironmental components interleukin (IL)-6 and fibronectin (FN) individually influence the proliferation and survival of Multiple Myeloma (MM) cells; however, in vivo these effectors most likely work together. We examined signaling events, cell cycle progression, and levels of drug response in MM cells either adhered to FN via β1 integrins, stimulated with IL-6, or treated with the two combined. While G1/S cell cycle arrest associated with FN adhesion was overcome when IL-6 as added, the cell adhesion mediated drug resistance (CAM-DR) was maintained in the presence of IL-6. Concomitant exposure of MM cells to IL-6 and FN adhesion revealed a dramatic increase in STAT3 phosphorylation, nuclear translocation and DNA-binding, as compared to either IL-6 or FN adhesion alone in four MM cell lines. Importantly, this increase in STAT3 activation correlated with a novel association between STAT3 and gp130 in cells adhered to FN prior to stimulation with IL-6, relative to non-adherent cells. Taken together, these results suggest a mechanism by which collaborative signaling by β1 integrin and gp130 confers an increased survival advantage to MM cells. PMID:19155309

  19. Expression of microRNA-30c via lentivirus vector inhibits the proliferation and enhances the sensitivity of highly aggressive ccRCC Caki-1 cells to anticancer agents

    PubMed Central

    Yang, Honglin; Song, Erlin; Shen, Guorong; Zhu, Tonghua; Jiang, Tingwang; Shen, Hao; Niu, Liping; Wang, Biao; Lu, Zhaoyang; Qian, Jianping

    2017-01-01

    The clear cell renal cell carcinoma (ccRCC) is one of the most fatal urologic tumors, and the prognosis remains very poor for advanced or metastatic ccRCC. This study reveals the roles of microRNA (miR)-30c in regulating a highly aggressive ccRCC cell line proliferation by targeting MTA-1, which is a key mediator for human cancer metastasis. Results from quantitative real-time polymerase chain reaction showed that the expression of MTA-1, the target of miR-30c, was significantly higher in metastatic ccRCC specimens than in nonmetastatic ccRCC or nontumor specimens. Accordingly, endogenous miR-30c is at a much lower level in highly aggressive ccRCC Caki-1 cells than nontumor or ccRCC cell lines. Expression of miR-30c via lentivirus vector inhibits the proliferation, anchorage-independent growth, in vitro invasion or migration, or in vivo growth of Caki-1 cells by repressing MTA-1 protein expression. miR-30c also enhances the sensitivity of Caki-1 cells to anticancer agents, including sorafenib and paclitaxel. These data reveal the potential application of miR-30c and that its targeting gene, MTA-1, would be a potential target in metastatic ccRCC treatment. PMID:28203091

  20. Expression of microRNA-30c via lentivirus vector inhibits the proliferation and enhances the sensitivity of highly aggressive ccRCC Caki-1 cells to anticancer agents.

    PubMed

    Yang, Honglin; Song, Erlin; Shen, Guorong; Zhu, Tonghua; Jiang, Tingwang; Shen, Hao; Niu, Liping; Wang, Biao; Lu, Zhaoyang; Qian, Jianping

    2017-01-01

    The clear cell renal cell carcinoma (ccRCC) is one of the most fatal urologic tumors, and the prognosis remains very poor for advanced or metastatic ccRCC. This study reveals the roles of microRNA (miR)-30c in regulating a highly aggressive ccRCC cell line proliferation by targeting MTA-1, which is a key mediator for human cancer metastasis. Results from quantitative real-time polymerase chain reaction showed that the expression of MTA-1, the target of miR-30c, was significantly higher in metastatic ccRCC specimens than in nonmetastatic ccRCC or nontumor specimens. Accordingly, endogenous miR-30c is at a much lower level in highly aggressive ccRCC Caki-1 cells than nontumor or ccRCC cell lines. Expression of miR-30c via lentivirus vector inhibits the proliferation, anchorage-independent growth, in vitro invasion or migration, or in vivo growth of Caki-1 cells by repressing MTA-1 protein expression. miR-30c also enhances the sensitivity of Caki-1 cells to anticancer agents, including sorafenib and paclitaxel. These data reveal the potential application of miR-30c and that its targeting gene, MTA-1, would be a potential target in metastatic ccRCC treatment.

  1. Nuclear Proliferation Challenges

    SciTech Connect

    Professor William Potter

    2005-11-28

    William C. Potter, Director of the Center for Non Proliferation Studies and the Center for Russian and Eurasian Studies at the Monterey Institute of International Studies, will present nuclear proliferation challenges following the 2005 Nuclear Non-Proliferation Treaty (NPT) Review Conference. In addition to elucidating reasons for, and implications of, the conference’s failure, Dr. Potter will discuss common ground between nuclear proliferation and terrorism issues and whether corrective action can be taken.

  2. Hepatic stellate cell-expressed endosialin balances fibrogenesis and hepatocyte proliferation during liver damage

    PubMed Central

    Mogler, Carolin; Wieland, Matthias; König, Courtney; Hu, Junhao; Runge, Anja; Korn, Claudia; Besemfelder, Eva; Breitkopf-Heinlein, Katja; Komljenovic, Dorde; Dooley, Steven; Schirmacher, Peter; Longerich, Thomas; Augustin, Hellmut G

    2015-01-01

    Liver fibrosis is a reversible wound-healing response to injury reflecting the critical balance between liver repair and scar formation. Chronic damage leads to progressive substitution of liver parenchyma by scar tissue and ultimately results in liver cirrhosis. Stromal cells (hepatic stellate cells [HSC] and endothelial cells) have been proposed to control the balance between liver fibrosis and regeneration. Here, we show that endosialin, a C-type lectin, expressed in the liver exclusively by HSC and portal fibroblasts, is upregulated in liver fibrosis in mouse and man. Chronic chemically induced liver damage resulted in reduced fibrosis and enhanced hepatocyte proliferation in endosialin-deficient (ENKO) mice. Correspondingly, acute-liver-damage-induced hepatocyte proliferation (partial hepatectomy) was increased in ENKO mice. A candidate-based screen of known regulators of hepatocyte proliferation identified insulin-like growth factor 2 (IGF2) as selectively endosialin-dependent hepatocyte mitogen. Collectively, the study establishes a critical role of HSC in the reciprocal regulation of fibrogenesis vs. hepatocyte proliferation and identifies endosialin as a therapeutic target in non-neoplastic settings. PMID:25680861

  3. A mechanism for the enhanced attachment and proliferation of fibroblasts on anodized 316L stainless steel with nano-pit arrays.

    PubMed

    Ni, Siyu; Sun, Linlin; Ercan, Batur; Liu, Luting; Ziemer, Katherine; Webster, Thomas J

    2014-08-01

    In this study, 316L stainless steel with tunable nanometer pit sizes (0, 25, 50, and 60 nm) were fabricated by an anodization procedure in an ethylene glycol electrolyte solution containing 5 vol % perchloric acid. The surface morphology and elemental composition of the 316L stainless steel were characterized by scanning electron microscopy (SEM), atomic force microscopy (AFM), and X-ray photoelectron spectroscopy (XPS). The nano-pit arrays on all of the 316L stainless steel samples were in a regular arrangement. The surface properties of the 316L stainless steel nano-pit surface showed improved wettability properties as compared with the untreated 316L stainless steel, as demonstrated by the lower contact angles which dropped from 83.0° to 28.6 to 45.4°. The anodized 316L stainless steel surfaces with 50 nm and 60 nm diameter pits were also more rough at the nanoscale. According to MTT assays, compared with unanodized (that is, nano-smooth) surfaces, the 50 and 60 nm diameter nano-pit surfaces dramatically enhanced initial human dermal fibroblast attachment and growth for up to 3 days in culture. Mechanistically, this study also provided the first evidence of greater select protein adsorption (specifically, vitronectin and fibronectin which have been shown to enhance fibroblast adhesion) on the anodized 316L stainless steel compared with unanodized stainless steel. Such nano-pit surfaces can be designed to support fibroblast growth and, thus, improve the use of 316L stainless steel for various implant applications (such as for enhanced skin healing for amputee devices and for percutaneous implants).

  4. Antimicrobial agent, tetracycline, enhanced upper alimentary tract Candida albicans infection and its related mucosal proliferation in alloxan-induced diabetic rats.

    PubMed

    Sano, Tomoya; Ozaki, Kiyokazu; Kodama, Yasushi; Matsuura, Tetsuro; Narama, Isao

    2012-10-01

    Alloxan-induced diabetic rats showed proliferative changes in the forestomach, accompanied by chronic inflammation, and one lesion progress to squamous cell carcinoma (SCC) without distant metastasis. The authors demonstrated that these lesions might be caused by Candida albicans infection. Antimicrobial therapy, particularly tetracycline treatment, has been blamed for a reduction in the number of competing bacterial organisms, which is frequently mentioned as a cause of candidiasis. The objective of this study is to ascertain whether or not tetracycline treatment can accelerate early-onset of C. albicans infection and the proliferative changes in this diabetic model. Alloxan-induced diabetic rats were given chlorinated water (AL group) and tetracycline solution (0.1% during week 1 and 0.01% thereafter) as drinking water (AT group). They were sacrificed after 25 weeks of drinking the treated water. The infection rate with C. albicans in the AT group was significantly higher than in the AL group. The incidence and severity of the squamous cell hyperplasia were enhanced in the AT group compared to the AL group. The proliferative lesions were consistently accompanied by inflammation and C. albicans infection in both groups. SCC was detected in one case in the AT group. These findings demonstrate that tetracycline induces C. albicans infection and enhances forestomach proliferative lesions in alloxan-induced diabetic rats.

  5. Effects of intermittent versus continuous parathyroid hormone administration on condylar chondrocyte proliferation and differentiation

    SciTech Connect

    Liu, Qi; Wan, Qilong; Yang, Rongtao; Zhou, Haihua; Li, Zubing

    2012-07-20

    Highlights: Black-Right-Pointing-Pointer Different PTH administration exerts different effects on condylar chondrocyte. Black-Right-Pointing-Pointer Intermittent PTH administration suppresses condylar chondrocyte proliferation. Black-Right-Pointing-Pointer Continuous PTH administration maintains condylar chondrocyte proliferating. Black-Right-Pointing-Pointer Intermittent PTH administration enhances condylar chondrocyte differentiation. -- Abstract: Endochondral ossification is a complex process involving chondrogenesis and osteogenesis regulated by many hormones and growth factors. Parathyroid hormone (PTH), one of the key hormones regulating bone metabolism, promotes osteoblast differentiation and osteogenesis by intermittent administration, whereas continuous PTH administration inhibits bone formation. However, the effects of PTH on chondrocyte proliferation and differentiation are still unclear. In this study, intermittent PTH administration presented enhanced effects on condylar chondrocyte differentiation and bone formation, as demonstrated by increased mineral nodule formation and alkaline phosphatase (ALP) activity, up-regulated runt-related transcription factor 2 (RUNX2), ALP, collagen type X (COL10a1), collagen type I (COL1a1), osteocalcin (OCN), bone sialoprotein (BSP), bone morphogenetic protein 2 (BMP2) and osterix (OSX) mRNA and/or protein expression. On the contrary, continuous PTH administration promoted condylar chondrocyte proliferation and suppressed its differentiation, as demonstrated by up-regulated collagen type II (COL2a1) mRNA expression, reduced mineral nodule formation and down-regulated expression of the mRNAs and/or proteins mentioned above. Our data suggest that PTH can regulate condylar chondrocyte proliferation and differentiation, depending on the type of PTH administration. These results provide new insight into the effects of PTH on condylar chondrocytes and new evidence for using local PTH administration to cure mandibular

  6. Synoviocyte Derived-Extracellular Matrix Enhances Human Articular Chondrocyte Proliferation and Maintains Re-Differentiation Capacity at Both Low and Atmospheric Oxygen Tensions

    PubMed Central

    Kean, Thomas J.; Dennis, James E.

    2015-01-01

    Background Current tissue engineering methods are insufficient for total joint resurfacing, and chondrocytes undergo de-differentiation when expanded on tissue culture plastic. De-differentiated chondrocytes show poor re-differentiation in culture, giving reduced glycosaminoglycan (GAG) and collagen matrix accumulation. To address this, porcine synoviocyte-derived extracellular matrix and low (5%) oxygen tension were assessed for their ability to enhance human articular chondrocyte expansion and maintain re-differentiation potential. Methods Porcine synoviocyte matrices were devitalized using 3 non-detergent methods. These devitalized synoviocyte matrices were compared against tissue culture plastic for their ability to support human chondrocyte expansion. Expansion was further compared at both low (5%), and atmospheric (20%) oxygen tension on all surfaces. Expanded cells then underwent chondrogenic re-differentiation in aggregate culture at both low and atmospheric oxygen tension. Aggregates were assessed for their GAG and collagen content both biochemically and histologically. Results Human chondrocytes expanded twice as fast on devitalized synoviocyte matrix vs. tissue culture plastic, and cells retained their re-differentiation capacity for twice the number of population doublings. There was no significant difference in growth rate between low and atmospheric oxygen tension. There was significantly less collagen type I, collagen type II, aggrecan and more MMP13 expression in cells expanded on synoviocyte matrix vs. tissue culture plastic. There were also significant effects due to oxygen tension on gene expression, wherein there was greater collagen type I, collagen type II, SOX9 and less MMP13 expression on tissue culture plastic compared to synoviocyte matrix. There was a significant increase in GAG, but not collagen, accumulation in chondrocyte aggregates re-differentiated at low oxygen tension over that achieved in atmospheric oxygen conditions. Conclusions

  7. MicroRNA-19a-3p enhances the proliferation and insulin secretion, while it inhibits the apoptosis of pancreatic β cells via the inhibition of SOCS3.

    PubMed

    Li, Yuan; Luo, Tianyou; Wang, Liang; Wu, Jing; Guo, Shixin

    2016-11-01

    MicroRNAs (miRNAs or miRs), a group of small non-coding RNAs, have been demonstrated to play key roles in various physicological processes and diseases, including diabetes, the most common metabolic disorder. However, the underlying mechanisms remains largely unknown. In this study, we aimed to investigate the role of miR‑19a‑3p in diabetes. The results of RT-qPCR demonstrated that the level of miR‑19a‑3p was significantly decreased in the diabetic patients, and that the decreased miR‑50a-5p level was significantly associated with a high concentration of blood glucose. miR‑19a‑3p mimic was further used to transfect pancreatic β cells, and we found that the overexpression of miR-19a-3p promoted cell proliferation and insulin secretion, while it suppressed the apoptosis of pancreatic β cells. Suppressor of cytokine signaling 3 (SOCS3) was further identified as a direct target gene of miR‑19a‑3p, and its protein level was significantly decreased following the overexpression of miR‑19a‑3p. Moreover, the siRNA-induced downregulation of SOCS3 also enhanced cell proliferation and insulin secretion, while it inhibited the apoptosis of pancreatic β cells. In addition, the overexpression of SOCS3 reversed the effects of miR‑19a‑3p overexpression on cell proliferation, insulin secretion and on the apoptosis of pancreatic β cells, which further indicates that SOCS3 acts as a downstream effector in the miR-19a-3p-mediated function of pancreatic β cells. Finally, the level of SOCS3 was increased in diabetic patients, and inversely correlated with the miR‑19a‑3p level, suggesting that the downregulation of miR-19a-3p leads to the upregulation of SOCS3, which contributes to the dysfunction of pancreatic β cells. On the whole, the findings of this study suggest that miR‑19a‑3p plays an important role in β cell function, and that the miR-19a-3p/SOCS3 axis may become a potential therapeutic target for diabetes.

  8. Modulation of the membrane type 1 matrix metalloproteinase cytoplasmic tail enhances tumor cell invasion and proliferation in three-dimensional collagen matrices.

    PubMed

    Moss, Natalie M; Wu, Yi I; Liu, Yueying; Munshi, H G; Stack, M Sharon

    2009-07-24

    Increasing evidence suggests that the cytoplasmic tail of membrane type 1 matrix metalloproteinase (MT1-MMP) is subject to phosphorylation and that this modification may influence its enzymatic activity at the cell surface. In this study, phosphorylated MT1-MMP is detected using a phospho-specific antibody recognizing a protein kinase C consensus sequence (phospho-TXR), and a MT1-MMP tail peptide is phosphorylated by exogenous protein kinase C. To characterize the potential role of cytoplasmic residue Thr(567) in these processes, mutants that mimic a state of either constitutive (T567E) or defective phosphorylation (T567A) were expressed and analyzed for their functional effects on MT1-MMP activity and cellular behavior. Phospho-mimetic mutants of Thr(567) exhibit enhanced matrix invasion as well as more extensive growth within a three-dimensional type I collagen matrix. Together, these findings suggest that MT1-MMP surface action is regulated by phosphorylation at cytoplasmic tail residue Thr(567) and that this modification plays a critical role in processes that are linked to tumor progression.

  9. Microfabricated discontinuous-edge surface topographies influence osteoblast adhesion, migration, cytoskeletal organization, and proliferation and enhance matrix and mineral deposition in vitro.

    PubMed

    Hamilton, D W; Wong, K S; Brunette, D M

    2006-05-01

    The fabrication of surfaces that stimulate increased adhesion, migration, and differentiated function of osteoblasts has been viewed as being desirable for many orthopedic applications. Previous studies have shown that microfabricated pits and grooves alter adhesion, spreading, matrix secretion, and production of mineral by rat calvarial osteoblasts (RCOs). The mechanisms underlying these effects are unknown, although microenvironment and cell alignment are considered to play a role. The aim of this work was to investigate the behavior of RCOs on microfabricated discontinuous-edge surfaces (DESs), which could provide an alternative means to control both the microenvironment and cellular alignment. Two types of discontinuous-type structures were employed, gap-cornered boxes and micron scale pillars. DES gap-cornered boxes and the pillars influenced the arrangement of F-actin, microtubules, and vinculin. Osteoblasts were guided in their direction of migration on both types of substrata. Both box DESs and pillars altered the staining intensity and localization pattern of phosphotyrosine and src-activated FAK localization. Cell multilayering, matrix deposition, and mineralization were enhanced on both discontinuous topographies when compared with smooth controls. This study shows that DESs alter adhesion, migration, and proliferative responses from osteoblasts at early time points (<1 week) and promote multilayering, matrix deposition, and mineral deposition at later times (2-6 weeks). Such topographical patterns could potentially be employed as effective surface features on bone-contacting implants or in membrane-based periodontal applications.

  10. Proliferation resistance of small modular reactors fuels

    SciTech Connect

    Polidoro, F.; Parozzi, F.; Fassnacht, F.; Kuett, M.; Englert, M.

    2013-07-01

    In this paper the proliferation resistance of different types of Small Modular Reactors (SMRs) has been examined and classified with criteria available in the literature. In the first part of the study, the level of proliferation attractiveness of traditional low-enriched UO{sub 2} and MOX fuels to be used in SMRs based on pressurized water technology has been analyzed. On the basis of numerical simulations both cores show significant proliferation risks. Although the MOX core is less proliferation prone in comparison to the UO{sub 2} core, it still can be highly attractive for diversion or undeclared production of nuclear material. In the second part of the paper, calculations to assess the proliferation attractiveness of fuel in typical small sodium cooled fast reactor show that proliferation risks from spent fuel cannot be neglected. The core contains a highly attractive plutonium composition during the whole life cycle. Despite some aspects of the design like the sealed core that enables easy detection of unauthorized withdrawal of fissile material and enhances proliferation resistance, in case of open Non-Proliferation Treaty break-out, weapon-grade plutonium in sufficient quantities could be extracted from the reactor core.

  11. Downregulation of miR-210 expression inhibits proliferation, induces apoptosis and enhances radiosensitivity in hypoxic human hepatoma cells in vitro

    SciTech Connect

    Yang, Wei; Sun, Ting; Cao, Jianping; Liu, Fenju; Tian, Ye; Zhu, Wei

    2012-05-01

    Hypoxia is a common feature of solid tumors and an important contributor to tumor radioresistance. miR-210 is the most consistently and robustly induced microRNA under hypoxia in different types of tumor cells and normal cells. In the present study, to explore the feasibility of miR-210 as an effective therapeutic target, lentiviral-mediated anti-sense miR-210 gene transfer technique was employed to downregulate miR-210 expression in hypoxic human hepatoma SMMC-7721, HepG2 and HuH7 cells, and phenotypic changes of which were analyzed. Hypoxia led to an increased hypoxia inducible factor-1{alpha} (HIF-1{alpha}) and miR-210 expression and cell arrest in the G{sub 0}/G{sub 1} phase in all cell lines. miR-210 downregulation significantly suppressed cell viability, induced cell arrest in the G{sub 0}/G{sub 1} phase, increased apoptotic rate and enhanced radiosensitivity in hypoxic human hepatoma cells. Moreover, apoptosis-inducing factor, mitochondrion-associated, 3 (AIFM3) was identified as a direct target gene of miR-210. AIFM3 downregulation by siRNA attenuated radiation induced apoptosis in miR-210 downregulated hypoxic human hepatoma cells. Taken together, these data suggest that miR-210 might be a potential therapeutic target and specific inhibition of miR-210 expression in combination with radiotherapy might be expected to exert strong anti-tumor effect on hypoxic human hepatoma cells. -- Highlights: Black-Right-Pointing-Pointer miR-210 downregulation radiosensitized hypoxic hepatoma. Black-Right-Pointing-Pointer AIFM3 was identified as a direct target gene of miR-210. Black-Right-Pointing-Pointer miR-210 might be a therapeutic target to hypoxic hepatoma.

  12. An ssDNA aptamer against mannose-capped lipoarabinomannan enhances anti-tuberculosis activity of macrophages through downregulation of lipid-sensing nuclear receptor peroxisome proliferator-activated receptor γ expression.

    PubMed

    Pan, Qin; Yan, Jiamin; Liu, Qi; Yuan, Chunhui; Zhang, Xiao-Lian

    2017-02-16

    Mannose-capped lipoarabinomannan (ManLAM) is an immunomodulatory epitope of Mycobacterium tuberculosis (Mtb). We previously generated an aptamer (ZXL1) that specifically binds to ManLAM from the virulent Mtb H37Rv strain and reported that ZXL1 functioned as an antagonist, inhibiting the ManLAM-induced immunosuppression of dendritic cells (DCs). In the present study, we found that ZXL1 inhibited Mtb entry into murine macrophages. ZXL1 enhanced IL-1β and IL-12 mRNA expression and cytokine production in ManLAM-treated macrophages but decreased IL-10 production. Inducible nitric oxide synthase (iNOS) expression in the macrophages was upregulated in the presence of ZXL1 after stimulation with ManLAM. ZXL1 also inhibited the expression of the lipid-sensing nuclear receptor peroxisome proliferator-activated receptor γ (PPARγ). These results suggest that ZXL1 promotes anti-tuberculosis activity through the downregulation of PPAR γ expression, which may contribute to M1 macrophage polarization and Mtb killing by macrophages.

  13. The Clustered, Regularly Interspaced, Short Palindromic Repeats-associated Endonuclease 9 (CRISPR/Cas9)-created MDM2 T309G Mutation Enhances Vitreous-induced Expression of MDM2 and Proliferation and Survival of Cells.

    PubMed

    Duan, Yajian; Ma, Gaoen; Huang, Xionggao; D'Amore, Patricia A; Zhang, Feng; Lei, Hetian

    2016-07-29

    The G309 allele of SNPs in the mouse double minute (MDM2) promoter locus is associated with a higher risk of cancer and proliferative vitreoretinopathy (PVR), but whether SNP G309 contributes to the pathogenesis of PVR is to date unknown. The clustered regularly interspaced short palindromic repeats (CRISPR)-associated endonuclease (Cas) 9 from Streptococcus pyogenes (SpCas9) can be harnessed to manipulate a single or multiple nucleotides in mammalian cells. Here we delivered SpCas9 and guide RNAs using dual adeno-associated virus-derived vectors to target the MDM2 genomic locus together with a homologous repair template for creating the mutation of MDM2 T309G in human primary retinal pigment epithelial (hPRPE) cells whose genotype is MDM2 T309T. The next-generation sequencing results indicated that there was 42.51% MDM2 G309 in the edited hPRPE cells using adeno-associated viral CRISPR/Cas9. Our data showed that vitreous induced an increase in MDM2 and subsequent attenuation of p53 expression in MDM2 T309G hPRPE cells. Furthermore, our experimental results demonstrated that MDM2 T309G in hPRPE cells enhanced vitreous-induced cell proliferation and survival, suggesting that this SNP contributes to the pathogenesis of PVR.

  14. Static magnetic field enhances the viability and proliferation rate of adipose tissue-derived mesenchymal stem cells potentially through activation of the phosphoinositide 3-kinase/Akt (PI3K/Akt) pathway.

    PubMed

    Marędziak, Monika; Tomaszewski, Krzysztof; Polinceusz, Paulina; Lewandowski, Daniel; Marycz, Krzysztof

    2017-01-01

    The aim of this work was to investigate the effects of 0.5T static magnetic field (sMF) on the viability and proliferation rate of human adipose-derived mesenchymal stromal stem cells (hASCs) via activation of the phosphoinositide 3-kinase/Akt (PI3K/Akt) signaling pathway. In a 7-d culture we examined cell growth kinetic and population doubling time (PDT). We also examined cell morphology and the cellular senescence markers level. Exposure to sMF enhanced the viability of these cells. However, the effect was blocked by treating the cells with LY294002, a P13K inhibitor. We compared this effect by Western Blot analysis of Akt protein expression. We also examined whether the cell response on sMF stimulation is dependent on integrin engagement and we measured integrin gene expression. Our results suggest that stimulation using sMF is a viable method to improve hASC viability. sMF is involved in mechanisms associated with controlling cell proliferative potential signaling events.

  15. Peroxisome proliferator-activated receptor-γ activation enhances insulin-stimulated glucose disposal by reducing ped/pea-15 gene expression in skeletal muscle cells: evidence for involvement of activator protein-1.

    PubMed

    Ungaro, Paola; Mirra, Paola; Oriente, Francesco; Nigro, Cecilia; Ciccarelli, Marco; Vastolo, Viviana; Longo, Michele; Perruolo, Giuseppe; Spinelli, Rosa; Formisano, Pietro; Miele, Claudia; Beguinot, Francesco

    2012-12-14

    The gene network responsible for inflammation-induced insulin resistance remains enigmatic. In this study, we show that, in L6 cells, rosiglitazone- as well as pioglitazone-dependent activation of peroxisome proliferator-activated receptor-γ (PPARγ) represses transcription of the ped/pea-15 gene, whose increased activity impairs glucose tolerance in mice and humans. Rosiglitazone enhanced insulin-induced glucose uptake in L6 cells expressing the endogenous ped/pea-15 gene but not in cells expressing ped/pea-15 under the control of an exogenous promoter. The ability of PPARγ to affect ped/pea-15 expression was also lost in cells and in C57BL/6J transgenic mice expressing ped/pea-15 under the control of an exogenous promoter, suggesting that ped/pea-15 repression may contribute to rosiglitazone action on glucose disposal. Indeed, high fat diet mice showed insulin resistance and increased ped/pea-15 levels, although these effects were reduced by rosiglitazone treatment. Both supershift and ChIP assays revealed the presence of the AP-1 component c-JUN at the PED/PEA-15 promoter upon 12-O-tetradecanoylphorbol-13-acetate stimulation of the cells. In these experiments, rosiglitazone treatment reduced c-JUN presence at the PED/PEA-15 promoter. This effect was not associated with a decrease in c-JUN expression. In addition, c-jun silencing in L6 cells lowered ped/pea-15 expression and caused nonresponsiveness to rosiglitazone, although c-jun overexpression enhanced the binding to the ped/pea-15 promoter and blocked the rosiglitazone effect. These results indicate that PPARγ regulates ped/pea-15 transcription by inhibiting c-JUN binding at the ped/pea-15 promoter. Thus, ped/pea-15 is downstream of a major PPARγ-regulated inflammatory network. Repression of ped/pea-15 transcription might contribute to the PPARγ regulation of muscle sensitivity to insulin.

  16. The Cytosolic Domain of Protein-tyrosine Kinase 7 (PTK7), Generated from Sequential Cleavage by a Disintegrin and Metalloprotease 17 (ADAM17) and γ-Secretase, Enhances Cell Proliferation and Migration in Colon Cancer Cells*

    PubMed Central

    Na, Hye-Won; Shin, Won-Sik; Ludwig, Andreas; Lee, Seung-Taek

    2012-01-01

    Protein-tyrosine kinase 7 (PTK7) is a member of the defective receptor protein-tyrosine kinases and is known to function as a regulator of planar cell polarity during development. Its expression is up-regulated in some cancers including colon carcinomas. A 100-kDa fragment of PTK7 was detected in the culture media from colon cancer cells and HEK293 cells. The shed fragment was named sPTK7-Ig1–7 because its molecular mass was very similar to that of the entire extracellular domain of PTK7 that contains immunoglobulin-like loops 1 to 7 (Ig1–7). The shedding of sPTK7-Ig1–7 was enhanced by treatment with phorbol 12-myristate 13-acetate. In addition to the sPTK7-Ig1–7 found in the culture medium, two C-terminal fragments of PTK7 were detected in the cell lysates: PTK7-CTF1, which includes a transmembrane segment and a cytoplasmic domain, and PTK7-CTF2, which lacks most of the transmembrane segment from PTK7-CTF1. Analysis of PTK7 processing in the presence of various protease inhibitors or after knockdown of potential proteases suggests that shedding of PTK7 into sPTK7-Ig1–7 and PTK7-CTF1 is catalyzed by ADAM17, and further cleavage of PTK7-CTF1 into PTK7-CTF2 is mediated by the γ-secretase complex. PTK7-CTF2 localizes to the nucleus and enhances proliferation, migration, and anchorage-independent colony formation. Our findings demonstrate a novel role for PTK7 in the tumorigenesis via generation of PTK7-CTF2 by sequential cleavage of ADAM17 and γ-secretase. PMID:22665490

  17. Suppression of estrogen receptor-alpha transactivation by thyroid transcription factor-2 in breast cancer cells

    SciTech Connect

    Park, Eunsook; Gong, Eun-Yeung; Romanelli, Maria Grazia; Lee, Keesook

    2012-05-11

    Highlights: Black-Right-Pointing-Pointer TTF-2 was expressed in mammary glands and breast cancer cells. Black-Right-Pointing-Pointer TTF-2 repressed ER{alpha} transactivation. Black-Right-Pointing-Pointer TTF-2 inhibited the proliferation of breast cancer cells. -- Abstract: Estrogen receptors (ERs), which mediate estrogen actions, regulate cell growth and differentiation of a variety of normal tissues and hormone-responsive tumors through interaction with cellular factors. In this study, we show that thyroid transcription factor-2 (TTF-2) is expressed in mammary gland and acts as ER{alpha} co-repressor. TTF-2 inhibited ER{alpha} transactivation in a dose-dependent manner in MCF-7 breast cancer cells. In addition, TTF-2 directly bound to and formed a complex with ER{alpha}, colocalizing with ER{alpha} in the nucleus. In MCF-7/TTF-2 stable cell lines, TTF-2 repressed the expression of endogenous ER{alpha} target genes such as pS2 and cyclin D1 by interrupting ER{alpha} binding to target promoters and also significantly decreased cell proliferation. Taken together, these data suggest that TTF-2 may modulate the function of ER{alpha} as a corepressor and play a role in ER-dependent proliferation of mammary cells.

  18. Harmine stimulates proliferation of human neural progenitors

    PubMed Central

    Dakic, Vanja; Maciel, Renata de Moraes; Drummond, Hannah; Nascimento, Juliana M.; Trindade, Pablo

    2016-01-01

    Harmine is the β-carboline alkaloid with the highest concentration in the psychotropic plant decoction Ayahuasca. In rodents, classical antidepressants reverse the symptoms of depression by stimulating neuronal proliferation. It has been shown that Ayahuasca presents antidepressant effects in patients with depressive disorder. In the present study, we investigated the effects of harmine in cell cultures containing human neural progenitor cells (hNPCs, 97% nestin-positive) derived from pluripotent stem cells. After 4 days of treatment, the pool of proliferating hNPCs increased by 71.5%. Harmine has been reported as a potent inhibitor of the dual specificity tyrosine-phosphorylation-regulated kinase (DYRK1A), which regulates cell proliferation and brain development. We tested the effect of analogs of harmine, an inhibitor of DYRK1A (INDY), and an irreversible selective inhibitor of monoamine oxidase (MAO) but not DYRK1A (pargyline). INDY but not pargyline induced proliferation of hNPCs similarly to harmine, suggesting that inhibition of DYRK1A is a possible mechanism to explain harmine effects upon the proliferation of hNPCs. Our findings show that harmine enhances proliferation of hNPCs and suggest that inhibition of DYRK1A may explain its effects upon proliferation in vitro and antidepressant effects in vivo. PMID:27957390

  19. Kuwanon V Inhibits Proliferation, Promotes Cell Survival and Increases Neurogenesis of Neural Stem Cells

    PubMed Central

    Kong, Sun-Young; Park, Min-Hye; Lee, Mina; Kim, Jae-Ouk; Lee, Ha-Rim; Han, Byung Woo; Svendsen, Clive N.; Sung, Sang Hyun; Kim, Hyun-Jung

    2015-01-01

    Neural stem cells (NSCs) have the ability to proliferate and differentiate into neurons and glia. Regulation of NSC fate by small molecules is important for the generation of a certain type of cell. The identification of small molecules that can induce new neurons from NSCs could facilitate regenerative medicine and drug development for neurodegenerative diseases. In this study, we screened natural compounds to identify molecules that are effective on NSC cell fate determination. We found that Kuwanon V (KWV), which was isolated from the mulberry tree (Morus bombycis) root, increased neurogenesis in rat NSCs. In addition, during NSC differentiation, KWV increased cell survival and inhibited cell proliferation as shown by 5-bromo-2-deoxyuridine pulse experiments, Ki67 immunostaining and neurosphere forming assays. Interestingly, KWV enhanced neuronal differentiation and decreased NSC proliferation even in the presence of mitogens such as epidermal growth factor and fibroblast growth factor 2. KWV treatment of NSCs reduced the phosphorylation of extracellular signal-regulated kinase 1/2, increased mRNA expression levels of the cyclin-dependent kinase inhibitor p21, down-regulated Notch/Hairy expression levels and up-regulated microRNA miR-9, miR-29a and miR-181a. Taken together, our data suggest that KWV modulates NSC fate to induce neurogenesis, and it may be considered as a new drug candidate that can regenerate or protect neurons in neurodegenerative diseases. PMID:25706719

  20. Enhancement by Enlargement: The Proliferation Security Initiative

    DTIC Science & Technology

    2008-01-01

    placed three of its principal ports (Hong Kong, Shanghai, and Shenzhen ) under the purview of CSI. Consequently, PSI can be accu- rately portrayed as only...three of its ports under CSI: Hong Kong, on May 5, 2003; Shanghai, on April 28, 2005; and Shenzhen , on June 24, 2005. Costs and Benefits of China’s PSI...has already placed three of its principal ports (Hong Kong, Shanghai, and Shenzhen ) under CSI. Consequently, PSI affiliation can be presented as a

  1. JPRS Report, Proliferation Issues

    DTIC Science & Technology

    2016-03-24

    Argentina To Import Reactor using chemical weapons. It informed a reporter from the NC2009075792 Cairo MENA in Arabic 1405 GMT Free Press Organization that...proliferation of chemical weapons as reflected pression system in which cool water under the reactor in the export control regime. The spokesman of the JPRS...This report contains foreign media information on issues related to worldwide proliferation and transfer activities in nuclear, chemical , and biological

  2. JPRS Report: Proliferation Issues

    DTIC Science & Technology

    2016-03-24

    report contains foreign media information on issues related to worldwide proliferation and transfer activities in nuclear, chemical , and biological...Intelligence Branch Head on Far East Weapons Threat [IDF Radio, 8 Jun 93] ............................. 12 Sarid: No More Nuclear Reactors To Be Built...Treaty," said Han, who is also unification minister. Non-Proliferation Treaty. Whether the proposed working-level contact to improve Asked about

  3. Hypoxia-inducible factor-2α: effect on radiation sensitivity and differential regulation by an mTOR inhibitor

    PubMed Central

    Bhatt, Rupal S.; Landis, Daniel M.; Zimmer, Michael; Torregrossa, Joelle; Chen, Shaoyong; Sukhatme, Vikas P.; Iliopoulos, Othon; Balk, Steve; Bubley, Glenn J.

    2014-01-01

    OBJECTIVE To determine the role of hypoxia-inducible factor-2α (HIF2α) on the sensitivity of renal cell carcinoma (RCC) cell lines to ionizing radiation and to determine if the mTOR antagonist, rapamycin, could decrease HIF2α protein levels. MATERIALS AND METHODS Cell lines expressing stable short-hairpin RNAs (shRNAs) encoding HIF2α shRNAs or an empty vector were transfected with a hypoxia responsive element (HRE)-driven firefly luciferase reporter gene. Two separate paired cell lines were assayed for their response to increasing doses of ionizing radiation. Proliferation and cell cycle kinetics were compared for cell lines expressing HIF2α shRNAs and empty vectors. The effect of an mTOR antagonist, rapamycin on HIF1α and HIF2α proteins levels was also assessed. RESULTS We confirmed that the 786-O RCC lines with stably integrated shRNAs against HIF2α had decreased activation of a plasmid with a HRE-driven firefly luciferase reporter gene. Lines from two separate cell clones with decreased HIF2α levels showed a significant increase in radiation sensitivity and an increase in G2 cell cycle arrest. Rapamycin, while effective in decreasing HIF1α protein levels, did not affect HIF2α levels in either of the RCC cell lines. CONCLUSIONS These results show that decreasing levels of HIF2α leads to an increased sensitivity to ionizing radiation. This finding may explain in part, the known resistance of RCC to radiation therapy. Although mTOR antagonists are approved for the treatment of RCC, these agents do not decrease HIF2α levels and therefore might not be effective in enhancing the radio-sensitivity of these tumours. PMID:18394010

  4. A small molecule inhibitor of monoubiquitinated Proliferating Cell Nuclear Antigen (PCNA) inhibits repair of interstrand DNA cross-link, enhances DNA double strand break, and sensitizes cancer cells to cisplatin.

    PubMed

    Inoue, Akira; Kikuchi, Sotaro; Hishiki, Asami; Shao, Youming; Heath, Richard; Evison, Benjamin J; Actis, Marcelo; Canman, Christine E; Hashimoto, Hiroshi; Fujii, Naoaki

    2014-03-07

    Small molecule inhibitors of proliferating cell nuclear antigen (PCNA)/PCNA interacting protein box (PIP-Box) interactions, including T2 amino alcohol (T2AA), inhibit translesion DNA synthesis. The crystal structure of PCNA in complex with T2AA revealed that T2AA bound to the surface adjacent to the subunit interface of the homotrimer of PCNA in addition to the PIP-box binding cavity. Because this site is close to Lys-164, which is monoubiquitinated by RAD18, we postulated that T2AA would affect monoubiquitinated PCNA interactions. Binding of monoubiquitinated PCNA and a purified pol η fragment containing the UBZ and PIP-box was inhibited by T2AA in vitro. T2AA decreased PCNA/pol η and PCNA/REV1 chromatin colocalization but did not inhibit PCNA monoubiquitination, suggesting that T2AA hinders interactions of pol η and REV1 with monoubiquitinated PCNA. Interstrand DNA cross-links (ICLs) are repaired by mechanisms using translesion DNA synthesis that is regulated by monoubiquitinated PCNA. T2AA significantly delayed reactivation of a reporter plasmid containing an ICL. Neutral comet analysis of cells receiving T2AA in addition to cisplatin revealed that T2AA significantly enhanced formation of DNA double strand breaks (DSBs) by cisplatin. T2AA promoted colocalized foci formation of phospho-ATM and 53BP1 and up-regulated phospho-BRCA1 in cisplatin-treated cells, suggesting that T2AA increases DSBs. When cells were treated by cisplatin and T2AA, their clonogenic survival was significantly less than that of those treated by cisplatin only. These findings show that the inhibitors of monoubiquitinated PCNA chemosensitize cells by inhibiting repair of ICLs and DSBs.

  5. Use of fibroblast growth factor 2 for expansion of chondrocytes and tissue engineering

    NASA Technical Reports Server (NTRS)

    Martin, Ivan (Inventor); Freed, Lisa E. (Inventor); Langer, Robert (Inventor); Vunjak-Novakovic, Gordana (Inventor)

    2003-01-01

    The present invention provides an improved method for expanding cells for use in tissue engineering. In particular the method provides specific biochemical factors to supplement cell culture medium during the expansion process in order to reproduce events occurring during embryonic development with the goal of regenerating tissue equivalents that resemble natural tissues both structurally and functionally. These specific biochemical factors improve proliferation of the cells and are capable of de-differentiation mature cells isolated from tissue so that the differentiation potential of the cells is preserved. The bioactive molecules also maintain the responsiveness of the cells to other bioactive molecules. Specifically, the invention provides methods for expanding chondrocytes in the presence of fibroblast growth factor 2 for use in regeneration of cartilage tissue.

  6. Defenses and disincentives to proliferation. Final report

    SciTech Connect

    Snipes, F.S.; Scesney, P.E.

    1992-03-02

    The proliferation of ballistic missiles and their associated technologies through the Third World has become a chief security concern for the United States and its allies. To meet this threat, the U.S. and other industrial nations have attempted to impose export controls on critical missile technologies in order to prohibit certain regimes from acquiring ballistic missile systems. Unfortunately, the controls have largely been ineffective as not only have ballistic missiles been acquired by dangerous Third World regimes, but often the technology and engineering expertise to indigenously produce these weapons have been obtained as well. Two major instances of ballistic missile use in the Third World--the Iran-Iraq War of the Cities and Desert Storm--have brought home the realization that arms control measures alone are not going to be successful in stopping proliferation of these weapons. Other responses to these systems are needed to enhance current arms control efforts. One of these responses is active ballistic missile defense. Desert Storm demonstrated the utility of defense as a response to the products of proliferation. Less obvious, but of great interest to SDI and U.S. foreign policy is how this demonstration of defensive prowess and subsequent development in defensive technologies will affect ballistic missile proliferation. The presence of defenses reduces the value of ballistic missiles that is determined by a potential proliferator. By doing so, defenses provide disincentives for regional countries to proliferate. Examining these disincentives is an integral part of determining the net value of defensive deployments.

  7. Fibroblast Growth Factor-2 Alters the Nature of Extinction

    ERIC Educational Resources Information Center

    Graham, Bronwyn M.; Richardson, Rick

    2011-01-01

    These experiments examined the effects of the NMDA-receptor (NMDAr) antagonist MK801 on reacquisition and re-extinction of a conditioned fear that had been previously extinguished before injection of fibroblast growth factor-2 (FGF2) or vehicle. Recent findings have shown that relearning and re-extinction, unlike initial learning and extinction,…

  8. Gravitational Bending of Starlight: Does the Factor 2 Vindicate Einstein?

    NASA Astrophysics Data System (ADS)

    Nyambuya, Golden G.

    2015-07-01

    As currently understood, the predictions of Newtonian and Einsteinian gravitation on the issue of the gravitational bending of starlight differ by a watershed factor "2" and this factor has been used to post Einsteinian gravitation as the superior gravitational model. The pioneering May 29, 1919, total eclipse observational measurements led by Sir Arthur S. Eddington heralded Einsteinian gravitation as the new superior model of gravitation by confirming this factor "2" which is assumed to be a prerogative prediction of Einsteinian gravitation. Subsequent eclipse observational measurements in the years (1922 - 1973) have reasonably agreed with the Eddington team. However, apart from the most precise quasar observational measurements made using the latest technologies of Very Large Baseline Array (VLBA), the factor "2" as measured in total eclipse observations is not exactly reproduced with the same hairs-breath accuracy as in the case of the VLBA measurements. Our result unequivocally demonstrates that if one where to preserve the identity of the inertia and gravitational mass of the photon in their calculations in the framework of Newtonian gravitation, the Newtonian gravitational paradigm can be brought into complete tandem with both the VLBA and eclipse observational measurements. Given the present result, the dominance of the Einsteinian gravitational paradigm since the Eddington measurement, and, the centrality and importance of this factor "2" in posting the Einsteinian paradigm as the superior model, this letter brings the reader to ponder and rethink the position of this factor "2" vis-a-vis its importance in overthrowing Newtonian gravitation as first assumed by the Eddington team.

  9. Effect of Fibroblast Growth Factor 2 on Equine Synovial Fluid Chondroprogenitor Expansion and Chondrogenesis

    PubMed Central

    Bianchessi, Marta; Chen, Yuwen; Durgam, Sushmitha; Pondenis, Holly; Stewart, Matthew

    2016-01-01

    Mesenchymal stem cells have been identified in the synovial fluid of several species. This study was conducted to characterize chondroprogenitor (CP) cells in equine synovial fluid (SF) and to determine the effect of fibroblast growth factor 2 (FGF-2) on SF-CP monolayer proliferation and subsequent chondrogenesis. We hypothesized that FGF-2 would stimulate SF-CP proliferation and postexpansion chondrogenesis. SF aspirates were collected from adult equine joints. Colony-forming unit (CFU) assays were performed during primary cultures. At first passage, SF-cells were seeded at low density, with or without FGF-2. Following monolayer expansion and serial immunophenotyping, cells were transferred to chondrogenic pellet cultures. Pellets were analyzed for chondrogenic mRNA expression and cartilage matrix secretion. There was a mean of 59.2 CFU/mL of SF. FGF-2 increased the number of population doublings during two monolayer passages and halved the population doubling times. FGF-2 did not alter the immunophenotype of SF-CPs during monolayer expansion, nor did FGF-2 compromise chondrogenesis. Hypertrophic phenotypic markers were not expressed in control or FGF-2 groups. FGF-2 did prevent the development of a “fibroblastic” cell layer around pellet periphery. FGF-2 significantly accelerates in vitro SF-CP expansion, the major hurdle to clinical application of this cell population, without detrimentally affecting subsequent chondrogenic capacity. PMID:26839571

  10. Proliferation: Threat and response

    SciTech Connect

    1996-04-01

    ;Table of Contents: Section I: The Regional Proliferation Challenge; Northeast Asia; The Middle East and North Africa; The Former Soviet Union: Russia, Ukrane, Kazakstan, And Belarus; South Asia; The International Threat: Dangers from Terrorism, Insurgencies, Civil Wars, And Organized Crime; Section II: Department of Defense Response; Technical Annex: Accessible Technologies; Glossary.

  11. JPRS Report, Proliferation Issues

    DTIC Science & Technology

    2016-03-24

    related to worldwide proliferation and transfer activities in nuclear, chemical , and biological weapons, including delivery systems and the transfer of...weapons-relevant technologies.] EAST ASIA JAPAN Mishap Detector To Be Installed on Russian Reactor [KYODO... Reactor logical affairs, as Japan’s representative to the governingboard of the center, it said. 0W2711131792 Tokyo KYODO in English 1222 GMT 27 Nov

  12. JPRS Report Proliferation Issues

    DTIC Science & Technology

    2016-03-24

    Britain are also involved in the project to improve the [Transmitted via KYODO] safety and design of the reactor used at the plant. Finnish specialists...information on issues related to worldwide proliferation and transfer activities in nuclear, chemical , and biological weapons, including delivery systems and...Ministry Official Missile Control, Korea [ZHONGGUO XINWEN SHE] .................................. 3 Spokesman Denies Export of Reactor to Syria [RENMIN

  13. JPRS Report, Proliferation Issues

    DTIC Science & Technology

    2016-03-24

    foreign media information on issues related to worldwide proliferation and transfer activities in nuclear, chemical , and biological weapons, including...I East Asia South Korea Scientist Urges ROK To Aid DPRK With Reactors ...14 Construction of Water-Type Nuclear Reactor To Begin 31 Jul [THENEWS, 30Jul 93] ............... 15 JPRS-TND-93-026 10 August 1993 2 Central

  14. JPRS Report, Proliferation Issues

    DTIC Science & Technology

    2016-03-24

    security for those who work at the facil- ities for scrapping chemical arms, and at improving the R. Kosyan also rejected the possibility that nuclear...report contains foreign media information on issues related to worldwide proliferation and transfer activities in nuclear, chemical , and biological...2 EAST EUROPE BULGARIA Trucks Carry ’ Chemical Warfare’ Cargo to Iraq [BTA] .................................................................... 3

  15. JPRS Report: Proliferation Issues

    DTIC Science & Technology

    2016-03-24

    foreign media information on issues related to worldwide proliferation and transfer activities in nuclear, chemical , and biological weapons, including...9 JPRS-TND-93-003 27 January 1993 2 SLOVAKIA Foreign Affairs Minister on Chemical Weapons [PRA VDA 16 Jan...10 IRAN Military Purchasing Agency Set Up in London [London PRESS ASSOCIATION] ....................... 10 Commentary Welcomes Convention on Chemical

  16. JPRS Report Proliferation Issues

    DTIC Science & Technology

    2016-03-24

    This report contains foreign media information on issues related to worldwide proliferation and transfer activities in nuclear, chemical , and...HUNGARY Government Tightens Chemical Arms Trade Controls [MTI] 10 YUGOSLAVIA Consortium Agrees To Build USSR Chemical Plant [TANJUG] 10...May Sell Nuclear Research Reactor to Iran [AFP] 14 Plans To Sell Iran Nuclear Reactor Denied [Beijing XINHUA] 14 Official Defends Right To

  17. JPRS Report, Proliferation Issues

    DTIC Science & Technology

    2016-03-24

    the more Krasnoyarsk hydroelectric power station. There is base, but also the chemical machine building plant, the an atomic reactor at the bottom of...issues related to worldwide proliferation and transfer activities in nuclear, chemical , and biological weapons, including delivery systems and the...7 PRC Chemical Company Establishes Seoul Office [THE KOREA HERALD 10 Dec] ............ 7 North

  18. JPRS Report, Proliferation Issues

    DTIC Science & Technology

    2016-03-24

    president said. MALAYSIA Soong said the federation would not know whether its members were producing reactors for Libya. Investigation of Libyan Chemical ...This report contains foreign media information on issues related to worldwide proliferation and transfer activities in nuclear, chemical , and...Continue’ [Frankfurt/Main FRANKFURTER ALLGEMEINE 19 Mar] .......... 15 MALAYSIA Investigation of Libyan Chemical Weapons Aid [AFP

  19. JPRS Report, Proliferation Issues

    DTIC Science & Technology

    2016-03-24

    December 1992 [This report contains foreign media information on issues related to worldwide proliferation and transfer activities in nuclear, chemical ...Nor Nuclear Test Site [Moscow INTERFAX] ...................... I Qian Qichen To Sign Chemical Weapons Convention in Paris [XINHUA...No. 2 Reactor for Startup [BTA] ............................................................ 3 Kozloduy Nuclear Plant May Lack Funds for Fuel

  20. JPRS Report, Proliferation Issues

    DTIC Science & Technology

    2016-03-24

    information on issues related to worldwide proliferation and transfer activities in nuclear, chemical , and biological weapons, including delivery systems and...I CHINA Russian Scientists To Cooperate in Nuclear Reactor Research [XINHUA] .............................................. 2 Beijing...Moscow To Cooperate on Hybrid Reactor [XINHUA] ................................................................ 2 Qian Qichen, ROK Foreign Minister

  1. JPRS Report: Proliferation Issues

    DTIC Science & Technology

    2016-03-24

    foreign media information on issues related to worldwide proliferation and transfer activities in nuclear, chemical, and biological weapons, including...delivery systems and the transfer of weapons-relevant technologies.] AFRICA SOUTH AFRICA Russian Offer To Launch Satellites Considered [SUNDAY TIMES 27...Iraqi Islamic Revolution] ................. 15 ISRAEL Charges of Technology Transfer to PRC ’Baseless’ /DA VAR 6 Jan

  2. β-Lactoglobulin Influences Human Immunity and Promotes Cell Proliferation

    PubMed Central

    Tai, Chun San; Chen, Yi Yun

    2016-01-01

    β-Lactoglobulin (LG) is suspected to enhance or modulate human immune responses. Moreover, LG is also hypothesized to increase human cell proliferation. However, these potential functions of LG have not been directly or thoroughly addressed. In this study, we demonstrated that LG is a potent stimulator of cell proliferation using a hybridoma cell (a splenocyte fused with a myeloma cell) model. LG's ability to promote cell proliferation was lost when the protein is denatured. To further investigate the influence of LG's conformation on cell proliferation, we chemically modified LG by either carboxymethylation (CM) or acetylation and observed significantly reduced cell proliferation when the protein structure was altered. Furthermore, we proved that LG enhances cell proliferation via receptor-mediated membrane IgM receptor. These data indicated that nondenatured LG is the major component in milk that modulates cell proliferation. Collectively, our study showed that LG plays a key role in enhancing immune responses by promoting cell proliferation through IgM receptor. PMID:27957499

  3. Upstream stimulatory factor 2 and hypoxia-inducible factor 2α (HIF2α) cooperatively activate HIF2 target genes during hypoxia.

    PubMed

    Pawlus, Matthew R; Wang, Liyi; Ware, Katie; Hu, Cheng-Jun

    2012-11-01

    While the functions of hypoxia-inducible factor 1α (HIF1α)/aryl hydrocarbon receptor nuclear translocator (ARNT) and HIF2α/ARNT (HIF2) proteins in activating hypoxia-inducible genes are well established, the role of other transcription factors in the hypoxic transcriptional response is less clear. We report here for the first time that the basic helix-loop-helix-leucine-zip transcription factor upstream stimulatory factor 2 (USF2) is required for the hypoxic transcriptional response, specifically, for hypoxic activation of HIF2 target genes. We show that inhibiting USF2 activity greatly reduces hypoxic induction of HIF2 target genes in cell lines that have USF2 activity, while inducing USF2 activity in cells lacking USF2 activity restores hypoxic induction of HIF2 target genes. Mechanistically, USF2 activates HIF2 target genes by binding to HIF2 target gene promoters, interacting with HIF2α protein, and recruiting coactivators CBP and p300 to form enhanceosome complexes that contain HIF2α, USF2, CBP, p300, and RNA polymerase II on HIF2 target gene promoters. Functionally, the effect of USF2 knockdown on proliferation, motility, and clonogenic survival of HIF2-dependent tumor cells in vitro is phenocopied by HIF2α knockdown, indicating that USF2 works with HIF2 to activate HIF2 target genes and to drive HIF2-depedent tumorigenesis.

  4. Motility, Survival and Proliferation

    PubMed Central

    Gerthoffer, William T.; Schaafsma, Dedmer; Sharma, Pawan; Ghavami, Saeid; Halayko, Andrew J

    2014-01-01

    Airway smooth muscle has classically been of interest for its contractile response linked to bronchoconstriction. However, terminally differentiated smooth muscle cells are phenotypically plastic and have multifunctional capacity for proliferation, cellular hypertrophy, migration, and the synthesis of extracellular matrix and inflammatory mediators. These latter properties of airway smooth muscle are important in airway remodeling which is a structural alteration that compounds the impact of contractile responses on limiting airway conductance. In this overview we describe the important signaling components and the functional evidence supporting a view of smooth muscle cells at the core of fibroproliferative remodeling of hollow organs. Signal transduction components and events are summarized that control the basic cellular processes of proliferation, cell survival, apoptosis and cellular migration. We delineate known intracellular control mechanisms and suggest future areas of interest to pursue to more fully understand factors that regulate normal myocyte function and airway remodeling in obstructive lung diseases. PMID:23728975

  5. Conditioned media from differentiating craniofacial bone marrow stromal cells influence mineralization and proliferation in periodontal ligament stem cells.

    PubMed

    Jin, Zhenyu; Feng, Yuan; Liu, Hongwei

    2016-10-01

    Previous reports have mainly focused on the behavioral responses of human periodontal ligament stem cells (hPDLSCs) in interaction with tibia bone marrow stromal cells (BMSCs). However, there is little study on the biologic features of hPDLSCs under the induction of maxilla BMSCs (M-BMSCs) at different phases of osteogenic differentiation. We hypothesized that M-BMSCs undergoing osteogenic differentiation acted on the proliferation, differentiation, and bone-forming capacity of hPDLSCs. In this paper, primary hPDLSCs and human M-BMSCs (hM-BMSCs) were expanded in vitro. After screening of surface markers for characterization, hPDLSCs were cocultured with different phases of differentiating hM-BMSCs. Cell proliferation and alkaline phosphatase activity were examined, and mineralization-associated markers such as osteocalcin and runt-related transcription factor 2 of hPDLSCs in coculture with uninduced/osteoinduced hM-BMSCs were evaluated. hPDLSCs in hM-BMSCs-conditioned medium (hM-BMSCs-CM) group showed a reduction in proliferation compared with untreated hPDLSCs, while osteoinduced hM-BMSCs for 10 day-conditioned medium (hM-BMSCs-CM-10ds) and osteoinduced hM-BMSCs for 15 day-conditioned medium (hM-BMSCs-CM-15ds) enhance the proliferation of hPDLSCs. hM-BMSCs of separate differentiation stages temporarily inhibited osteogenesis of hPDLSCs in the early days. Upon extending time periods, uninduced/osteoinduced hM-BMSCs markedly enhanced osteogenesis of hPDLSCs to different degrees. The transplantation results showed hM-BMSCs-CM-15ds treatment promoted tissue regeneration to generate cementum/periodontal ligament-like structure characterized by hard-tissue formation. This research supported the notion that hM-BMSCs triggered osteogenesis of hPDLSCs suggesting important implications for periodontal engineering.

  6. JPRS report proliferation issues

    SciTech Connect

    1991-09-27

    This report contains foreign media information on issues related to worldwide proliferation and transfer activities in nuclear, chemical, and biological weapons, including delivery systems and the transfer of weapons relevant technologies. The following locations are included: (1) South Africa, Namibia; (2) China; (3) South Korea, Australia, Indonesia, Japan, Philippines; (4) Yugoslavia; (5) Brazil, Argentina, Cuba; (6) India, Libya, Pakistan; (7) Soviet Union; and (8) France, Germany, Netherlands.

  7. JPRS report proliferation issues

    SciTech Connect

    1991-11-07

    This report contains foreign media information on issues related to worldwide proliferation and transfer activities in nuclear, chemical, and biological weapons, including delivery systems and the transfer of weapons relevant technologies. The following locations are included: (1) South Africa; (2) China; (3) North and South Korea, Japan; (4) Bulgaria, Czechoslovakia; (5) Argentina, Brazil; (6) India, Iran, Israel, Pakistan, Libya, Iraq, Egypt; (7) Soviet Union; and (8) Belgium, Germany, United Kingdom, Netherlands, France.

  8. JPRS Report, Proliferation Issues

    DTIC Science & Technology

    2016-03-24

    said. "Iraqis also concentrated on a chemical method designed by the French," but which Iraq managed to improve , Kay added. The final method is...information on issues related to worldwide proliferation and transfer activities in nuclear chemical , and biological weapons, including delivery systems and...the transfer of weapons-relevant technologies.] CHINA Nuclear Reactor in Sichuan Begins Operation [Hong Kong WEN WEI PO 6 Aug] j Country To

  9. JPRS Report: Proliferation Issues

    DTIC Science & Technology

    2016-03-24

    1993 [This report contains foreign media information on issues related to worldwide proliferation and transfer activities in nuclear, chemical , and...will be working similar gates are installed at all checkpoints, there is no in Gubin and Dorohusk and five other towns (see chart way to improve the...weapon has actually been made as a result of diversion. cannot be achieved by giving up its nuclear weapon If you bar the early dual-purpose reactors

  10. JPRS Report, Proliferation Issues

    DTIC Science & Technology

    2016-03-24

    media information on issues related to worldwide proliferation and transfer activities in nuclear, chemical , and biological weapons, including... Reactor Refurbished, Ready To Start Up [NEPSZABADSAG 25 Nov] 11 JPRS-TND-92-047 18 December 1992 2 NEAR EAST & SOUTH ASIA EGYPT U.S...supplies technology related to aerosol physics to sectors such as the chemical and petro- chemical industries and pollu- tion-control equipment

  11. JPRS Report, Proliferation Issues

    DTIC Science & Technology

    2016-03-24

    contains foreign media information on issues related to worldwide proliferation and transfer activities in nuclear, chemical , and biological weapons...including delivery systems and the transfer of weapons-relevant technologies.] AFRICA SOUTH AFRICA Vice Admiral on ’Defensive’ Chemical , Biological...Angola) directed the defensive Vice Admiral on ’Defensive’ Chemical , Biological program against the threat posed by the classical chem- Warfare ical

  12. Proliferating pilomatricoma - Case report*

    PubMed Central

    Kondo, Rogerio Nabor; Pontello Junior, Rubens; Belinetti, Francine Milenkovich; Cilião, Caroline; Vasconcellos, Vanessa Regina Bulla; Grimaldi, Dora Maria

    2015-01-01

    Proliferating pilomatricoma is proliferative, rare tumor variant of pilomatricoma. It is a benign neoplasm of hair matrix that can have potentially involve local recurrence. We report the case of a 60-year-old man who presented an asymptomatic nodule on the scalp. Histological exam demonstrated a basaloid epithelium at the periphery, filled with eosinophilic cornified material containing shadow cells. The tumor was excised and there was no evidence of recurrence one year later. PMID:26312685

  13. Regulation of physicochemical properties, osteogenesis activity, and fibroblast growth factor-2 release ability of β-tricalcium phosphate for bone cement by calcium silicate.

    PubMed

    Su, Ching-Chuan; Kao, Chia-Tze; Hung, Chi-Jr; Chen, Yi-Jyun; Huang, Tsui-Hsien; Shie, Ming-You

    2014-04-01

    β-Tricalcium phosphate (β-TCP) is an osteoconductive material. For this research we have combined it with a low degradation calcium silicate (CS) to enhance its bioactive and osteostimulative properties. To check its effectiveness, a series of β-TCP/CS composites with different ratios were prepared to make new bioactive and biodegradable biocomposites for bone repair. Formation of bone-like apatite, the diametral tensile strength, and weight loss of composites were considered before and after immersion in simulated body fluid (SBF). In addition, we also examined the effects of fibroblast growth factor-2 (FGF-2) released from β-TCP/CS composites and in vitro human dental pulp cell (hDPC) and studied its behavior. The results showed that the apatite deposition ability of the β-TCP/CS composites was enhanced as the CS content was increased. For composites with more than 50% CS contents, the samples were completely covered by a dense bone-like apatite layer. At the end of the immersion point, weight losses of 19%, 24%, 33%, 42%, and 51% were observed for the composites containing 0%, 30%, 50%, 70% and 100% β-TCP cements, respectively. In vitro cell experiments show that the CS-rich composites promote human dental pulp cell (hDPC) proliferation and differentiation. However, when the CS quantity in the composite is less than 70%, the amount of cells and osteogenesis protein of hDPCs was stimulated by FGF-2 released from β-TCP/CS composites. The combination of FGF-2 in degradation of β-TCP and osteogenesis of CS gives a strong reason to believe that these calcium-based composite cements may prove to be promising bone repair materials.

  14. ETOH inhibits embryonic neural stem/precursor cell proliferation via PLD signaling

    SciTech Connect

    Fujita, Yuko; Hiroyama, Masami; Sanbe, Atsushi Yamauchi, Junji; Murase, Shoko; Tanoue, Akito

    2008-05-23

    While a mother's excessive alcohol consumption during pregnancy is known to have adverse effects on fetal neural development, little is known about the underlying mechanism of these effects. In order to investigate these mechanisms, we investigated the toxic effect of ethanol (ETOH) on neural stem/precursor cell (NSC) proliferation. In cultures of NSCs, phospholipase D (PLD) is activated following stimulation with epidermal growth factor (EGF) and fibroblast growth factor 2 (FGF2). Exposure of NSCs to ETOH suppresses cell proliferation, while it has no effect on cell death. Phosphatidic acid (PA), which is a signaling messenger produced by PLD, reverses ETOH inhibition of NSC proliferation. Blocking the PLD signal by 1-butanol suppresses the proliferation. ETOH-induced suppression of NSC proliferation and the protective effect of PA for ETOH-induced suppression are mediated through extracellular signal-regulated kinase signaling. These results indicate that exposure to ETOH impairs NSC proliferation by altering the PLD signaling pathway.

  15. ETOH inhibits embryonic neural stem/precursor cell proliferation via PLD signaling.

    PubMed

    Fujita, Yuko; Hiroyama, Masami; Sanbe, Atsushi; Yamauchi, Junji; Murase, Shoko; Tanoue, Akito

    2008-05-23

    While a mother's excessive alcohol consumption during pregnancy is known to have adverse effects on fetal neural development, little is known about the underlying mechanism of these effects. In order to investigate these mechanisms, we investigated the toxic effect of ethanol (ETOH) on neural stem/precursor cell (NSC) proliferation. In cultures of NSCs, phospholipase D (PLD) is activated following stimulation with epidermal growth factor (EGF) and fibroblast growth factor 2 (FGF2). Exposure of NSCs to ETOH suppresses cell proliferation, while it has no effect on cell death. Phosphatidic acid (PA), which is a signaling messenger produced by PLD, reverses ETOH inhibition of NSC proliferation. Blocking the PLD signal by 1-butanol suppresses the proliferation. ETOH-induced suppression of NSC proliferation and the protective effect of PA for ETOH-induced suppression are mediated through extracellular signal-regulated kinase signaling. These results indicate that exposure to ETOH impairs NSC proliferation by altering the PLD signaling pathway.

  16. Interleukin-21 (IL-21) synergizes with IL-2 to enhance T-cell receptor-induced human T-cell proliferation and counteracts IL-2/transforming growth factor-β-induced regulatory T-cell development

    PubMed Central

    Battaglia, Alessandra; Buzzonetti, Alexia; Baranello, Cinzia; Fanelli, Mara; Fossati, Marco; Catzola, Valentina; Scambia, Giovanni; Fattorossi, Andrea

    2013-01-01

    Interleukin-2 (IL-2) is a mainstay for current immunotherapeutic protocols but its usefulness in patients is reduced by severe toxicities and because IL-2 facilitates regulatory T (Treg) cell development. IL-21 is a type I cytokine acting as a potent T-cell co-mitogen but less efficient than IL-2 in sustaining T-cell proliferation. Using various in vitro models for T-cell receptor (TCR)-dependent human T-cell proliferation, we found that IL-21 synergized with IL-2 to make CD4+ and CD8+ T cells attain a level of expansion that was impossible to obtain with IL-2 alone. Synergy was mostly evident in naive CD4+ cells. IL-2 and tumour-released transforming growth factor-β (TGF-β) are the main environmental cues that cooperate in Treg cell induction in tumour patients. Interleukin-21 hampered Treg cell expansion induced by IL-2/TGF-β combination in naive CD4+ cells by facilitating non-Treg over Treg cell proliferation from the early phases of cell activation. Conversely, IL-21 did not modulate the conversion of naive activated CD4+ cells into Treg cells in the absence of cell division. Treg cell reduction was related to persistent activation of Stat3, a negative regulator of Treg cells associated with down-modulation of IL-2/TGF-β-induced phosphorylation of Smad2/3, a positive regulator of Treg cells. In contrast to previous studies, IL-21 was completely ineffective in counteracting the suppressive activity of Treg cells on naive and memory, CD4+ and CD8+ T cells. Present data provide proof-of-concept for evaluating a combinatorial approach that would reduce the IL-2 needed to sustain T-cell proliferation efficiently, thereby reducing toxicity and controlling a tolerizing mechanism responsible for the contraction of the T-cell response. PMID:23278180

  17. Protein-Binding Function of RNA-Dependent Protein Kinase Promotes Proliferation through TRAF2/RIP1/NF-κB/c-Myc Pathway in Pancreatic β cells

    PubMed Central

    Gao, LiLi; Tang, Wei; Ding, ZhengZheng; Wang, DingYu; Qi, XiaoQiang; Wu, HuiWen; Guo, Jun

    2015-01-01

    Double-stranded RNA-dependent protein kinase (PKR), an intracellular pathogen recognition receptor, is involved both in insulin resistance in peripheral tissues and in downregulation of pancreatic β-cell function in a kinase-dependent manner, indicating PKR as a core component in the progression of type 2 diabetes. PKR also acts as an adaptor protein via its protein-binding domain. Here, the PKR protein-binding function promoted β-cell proliferation without its kinase activity, which is associated with enhanced physical interaction with tumor necrosis factor receptor-associated factor 2 (TRAF2) and TRAF6. In addition, the transcription of the nuclear factor kappa-light-chain-enhancer of activated B cell (NF-κB)-dependent survival gene c-Myc was upregulated significantly and is necessary for proliferation. Upregulation of the PKR protein-binding function induced the NF-κB pathway, as observed by dose-dependent degradation of IκBα, induced nuclear translocation of p65 and elevated NF-κB-dependent reporter gene expression. NF-κB-dependent reporter activity and β-cell proliferation both were suppressed by TRAF2-siRNA, but not by TRAF6-siRNA. TRAF2-siRNA blocked the ubiquitination of receptor-interacting serine/threonine-protein kinase 1 (RIP1) induced by PKR protein binding. Furthermore, RIP1-siRNA inhibited β-cell proliferation. Proinflammatory cytokines (TNFα) and glucolipitoxicity also promoted the physical interaction of PKR with TRAF2. Collectively, these data indicate a pivotal role for PKR’s protein-binding function on the proliferation of pancreatic β cells through TRAF2/RIP1/NF-κB/c-Myc pathways. Therapeutic opportunities for type 2 diabetes may arise when its kinase catalytic function, but not its protein-binding function, is downregulated. PMID:25715336

  18. Consumption of cranberry polyphenols enhances human γδ-T cell proliferation and reduces the number of symptoms associated with colds and influenza: a randomized, placebo-controlled intervention study

    PubMed Central

    2013-01-01

    Background Our main objective was to evaluate the ability of cranberry phytochemicals to modify immunity, specifically γδ-T cell proliferation, after daily consumption of a cranberry beverage, and its effect on health outcomes related to cold and influenza symptoms. Methods The study was a randomized, double-blind, placebo-controlled, parallel intervention. Subjects drank a low calorie cranberry beverage (450 ml) made with a juice-derived, powdered cranberry fraction (n = 22) or a placebo beverage (n = 23), daily, for 10 wk. PBMC were cultured for six days with autologous serum and PHA-L stimulation. Cold and influenza symptoms were self-reported. Results The proliferation index of γδ-T cells in culture was almost five times higher after 10 wk of cranberry beverage consumption (p <0.001). In the cranberry beverage group, the incidence of illness was not reduced, however significantly fewer symptoms of illness were reported (p = 0.031). Conclusions Consumption of the cranberry beverage modified the ex vivo proliferation of γδ-T cells. As these cells are located in the epithelium and serve as a first line of defense, improving their function may be related to reducing the number of symptoms associated with a cold and flu. Trial registration ClinicalTrials.gov Identifier: NCT01398150. PMID:24330619

  19. OLA1, a Translational Regulator of p21, Maintains Optimal Cell Proliferation Necessary for Developmental Progression

    PubMed Central

    Ding, Zonghui; Liu, Yue; Rubio, Valentina; He, Jinjie; Minze, Laurie J.

    2016-01-01

    OLA1, an Obg-family GTPase, has been implicated in eukaryotic initiation factor 2 (eIF2)-mediated translational control, but its physiological functions remain obscure. Here we report that mouse embryos lacking OLA1 have stunted growth, delayed development leading to immature organs—especially lungs—at birth, and frequent perinatal lethality. Proliferation of primary Ola1−/− mouse embryonic fibroblasts (MEFs) is impaired due to defective cell cycle progression, associated with reduced cyclins D1 and E1, attenuated Rb phosphorylation, and increased p21Cip1/Waf1. Accumulation of p21 in Ola1−/− MEFs is due to enhanced mRNA translation and can be prevented by either reconstitution of OLA1 expression or treatment with an eIF2α dephosphorylation inhibitor, suggesting that OLA1 regulates p21 through a translational mechanism involving eIF2. With immunohistochemistry, overexpression of p21 protein was detected in Ola1-null embryos with reduced cell proliferation. Moreover, we have generated p21−/− Ola1−/− mice and found that knockout of p21 can partially rescue the growth retardation defect of Ola1−/− embryos but fails to rescue them from developmental delay and the lethality. These data demonstrate, for the first time, that OLA1 is required for normal progression of mammalian development. OLA1 plays an important role in promoting cell proliferation at least in part through suppression of p21 and organogenesis via factors yet to be discovered. PMID:27481995

  20. Elongation factor-2: a useful gene for arthropod phylogenetics.

    PubMed

    Regier, J C; Shultz, J W

    2001-07-01

    Robust resolution of controversial higher-level groupings within Arthropoda requires additional sources of characters. Toward this end, elongation factor-2 sequences (1899 nucleotides) were generated from 17 arthropod taxa (5 chelicerates, 6 crustaceans, 3 hexapods, 3 myriapods) plus an onychophoran and a tardigrade as outgroups. Likelihood and parsimony analyses of nucleotide and amino acid data sets consistently recovered Myriapoda and major chelicerate groups with high bootstrap support. Crustacea + Hexapoda (= Pancrustacea) was recovered with moderate support, whereas the conflicting group Myriapoda + Hexapoda (= Atelocerata) was never recovered and bootstrap values were always <5%. With additional nonarthropod sequences included, one indel supports monophyly of Tardigrada, Onychophora, and Arthropoda relative to molluscan, annelidan, and mammalian outgroups. New and previously published sequences from RNA polymerase II (1038 nucleotides) and elongation factor-1alpha (1092 nucleotides) were analyzed for the same taxa. A comparison of bootstrap values from the three genes analyzed separately revealed widely varying values for some clades, although there was never strong support for conflicting groups. In combined analyses, there was strong bootstrap support for the generally accepted clades Arachnida, Arthropoda, Euchelicerata, Hexapoda, and Pycnogonida, and for Chelicerata, Myriapoda, and Pancrustacea, whose monophyly is more controversial. Recovery of some additional groups was fairly robust to method of analysis but bootstrap values were not high; these included Pancrustacea + Chelicerata, Hexapoda + Cephalocarida + Remipedia, Cephalocarida + Remipedia, and Malaocostraca + Cirripedia. Atelocerata (= Myriapoda + Hexapoda) was never recovered. Elongation factor-2 is now the second protein-encoding, nuclear gene (in addition to RNA polymerase II) to support Pancrustacea over Atelocerata. Atelocerata is widely cited in morphology-based analyses, and the

  1. The regulation of runt-related transcription factor 2 by fibroblast growth factor-2 and connexin43 requires the inositol polyphosphate/protein kinase Cδ cascade.

    PubMed

    Niger, Corinne; Luciotti, Maria A; Buo, Atum M; Hebert, Carla; Ma, Vy; Stains, Joseph P

    2013-06-01

    Connexin43 (Cx43) plays a critical role in osteoblast function and bone mass accrual, yet the identity of the second messengers communicated by Cx43 gap junctions, the targets of these second messengers and how they regulate osteoblast function remain largely unknown. We have shown that alterations of Cx43 expression in osteoblasts can impact the responsiveness to fibroblast growth factor-2 (FGF2), by modulating the transcriptional activity of runt-related transcription factor 2 (Runx2). In this study, we examined the contribution of the phospholipase Cγ1/inositol polyphosphate/protein kinase C delta (PKCδ) cascade to the Cx43-dependent transcriptional response of MC3T3 osteoblasts to FGF2. Knockdown of expression and/or inhibition of function of phospholipase Cγ1, inositol polyphosphate multikinase, which generates inositol 1,3,4,5-tetrakisphosphate (InsP₄) and InsP₅, and inositol hexakisphosphate kinase 1/2, which generates inositol pyrophosphates, prevented the ability of Cx43 to potentiate FGF2-induced signaling through Runx2. Conversely, overexpression of phospholipase Cγ1 and inositol hexakisphosphate kinase 1/2 enhanced FGF2 activation of Runx2 and the effect of Cx43 overexpression on this response. Disruption of these pathways blocked the nuclear accumulation of PKCδ and the FGF2-dependent interaction of PKCδ and Runx2, reducing Runx2 transcriptional activity. These data reveal that FGF2-signaling involves the inositol polyphosphate cascade, including inositol hexakisphosphate kinase (IP6K), and demonstrate that IP6K regulates Runx2 and osteoblast gene expression. Additionally, these data implicate the water-soluble inositol polyphosphates as mediators of the Cx43-dependent amplification of the osteoblast response to FGF2, and suggest that these low molecular weight second messengers may be biologically relevant mediators of osteoblast function that are communicated by Cx43-gap junctions.

  2. Enhanced effect of fibroblast growth factor-2-containing dalteparin/protamine nanoparticles on hair growth

    PubMed Central

    Takabayashi, Yuki; Nambu, Masaki; Ishihara, Masayuki; Kuwabara, Masahiro; Fukuda, Koichi; Nakamura, Shingo; Hattori, Hidemi; Kiyosawa, Tomoharu

    2016-01-01

    Purpose Although treatments for alopecia are in high demand, not all treatments are safe and reliable. Dalteparin/protamine nanoparticles (D/P NPs) can effectively carry growth factors (GFs) such as fibroblast GF (FGF)-2. The purpose of this study was to identify the effects of FGF-2-containing D/P NPs (FGF-2&D/P NPs) on hair growth. Patients and methods In this study, the participants were 12 volunteers with thin hair. One milliliter of FGF-2 (100 ng/mL) and D/P NPs (56 μg/mL) was applied and massaged on the skin of the scalp by the participants twice a day. They were evaluated for 6 months. Participants were photographed using a digital camera for general observation and a hair diagnosis system for measuring hair diameter. Results The mean diameter of the hairs was significantly higher following the application of FGF-2&D/P NPs for 6 months. Objective improvements in thin hair were observed in two cases. Nine participants experienced greater bounce and hair resilience. Conclusion The transdermal application of FGF-2&D/P NPs to the scalp can be used as a new treatment for alopecia. PMID:27274299

  3. Expression of paired-like homeodomain transcription factor 2c (PITX2c) in epidermal keratinocytes

    SciTech Connect

    Shi, Ge; Sohn, Kyung-Cheol; Choi, Tae-Young; Choi, Dae-Kyoung; Lee, Sang-Sin; Ou, Bai-sheng; Kim, Sooil; Lee, Young Ho; Yoon, Tae-Jin; Kim, Seong-Jin; Lee, Young; Seo, Young-Joon; Lee, Jeung-Hoon; Kim, Chang Deok

    2010-11-15

    Paired-like homeodomain transcription factor 2 (PITX2) has been implicated as one of the genes responsible for Rieger syndrome. It has been also shown to play a central role during development. In this study, we investigated the functional role of PITX2 in keratinocyte differentiation. RT-PCR analysis showed that PITX2c isoform was predominantly expressed in a differentiation-dependent manner. Consistent with, immunohistochemical staining showed that PITX2 expression was increased in the upper layer of epidermis. When PITX2c was overexpressed in cultured keratinocytes by a recombinant adenovirus, the differentiation markers such as involucrin and loricrin were significantly increased at both mRNA and protein levels. In addition, PITX2c overexpression led to the decrease of cell growth, concomitantly with the upregulation of cell cycle-related genes p21. To investigate the effect of PITX2c in vivo, we microinjected PITX2c expression vector into zebrafish embryo. Interestingly, overexpression of PITX2c in zebrafish embryo led to the formation of horn-like structure and thickening of epidermis, together with the increase of keratin 8 (K8) expression. These results suggest that PITX2c has a role in proliferation and differentiation of epidermal keratinocytes.

  4. Selection and characterization of a human neutralizing antibody to human fibroblast growth factor-2

    SciTech Connect

    Tao, Jun; Xiang, Jun-Jian; Li, Dan; Deng, Ning; Wang, Hong; Gong, Yi-Ping

    2010-04-09

    Compelling evidences suggest that fibroblast growth factor-2 (FGF-2) plays important roles in tumor growth, angiogenesis and metastasis. Molecules blocking the FGF-2 signaling have been proposed as anticancer agents. Through screening of a human scFv phage display library, we have isolated several human single-chain Fv fragments (scFvs) that bind to human FGF-2. After expression and purification in bacteria, one scFv, named 1A2, binds to FGF-2 with a high affinity and specificity, and completes with FGF-2 binding to its receptor. This 1A2 scFv was then cloned into the pIgG1 vector and expressed in 293T cells. The purified hIgG1-1A2 antibody showed a high binding affinity of 8 x 10{sup -9} M to rhFGF-2. In a set of vitro assays, it inhibited various biological activities of FGF-2 such as the proliferation, migration and tube formation of human umbilical vein endothelial cells. More importantly, hIgG1-1A2 antibody also efficiently blocked the growth while inducing apoptosis of glioma cells. For the first time, we generated a human anti-FGF-2 antibody with proven in vitro anti-tumor activity. It may therefore present a new therapeutic candidate for the treatment of cancers that are dependent on FGF-2 signaling for growth and survival.

  5. Small molecule modulators of eukaryotic initiation factor 2α kinases, the key regulators of protein synthesis.

    PubMed

    Joshi, Manali; Kulkarni, Abhijeet; Pal, Jayanta K

    2013-11-01

    Eukaryotic initiation factor 2 alpha kinases (eIF-2α kinases) are key mediators of stress response in cells. In mammalian cells, there are four eIF-2α kinases, namely HRI (Heme-Regulated Inhibitor), PKR (RNA-dependent Protein Kinase), PERK (PKR-like ER Kinase) and GCN2 (General Control Non-derepressible 2). These kinases get activated during diverse cytoplasmic stress conditions and phosphorylate the alpha-subunit of eIF2, leading to global protein synthesis inhibition. Therefore, eIF-2α kinases play a vital role in various cellular processes such as proliferation, differentiation, apoptosis and cell signaling. Deregulation of eIF-2α kinases and protein synthesis has been linked to numerous pathological conditions such as certain cancers, anemia and neurodegenerative disorders. Thus, modulation of these kinases by small molecules holds a great therapeutic promise. In this review we have compiled the available information on inhibitors and activators of these four eIF-2α kinases. The review concludes with a note on the selectivity issue of currently available modulators and future perspectives for the design of specific small molecule probes.

  6. Type-specific roles of histone deacetylase (HDAC) overexpression in ovarian carcinoma: HDAC1 enhances cell proliferation and HDAC3 stimulates cell migration with downregulation of E-cadherin.

    PubMed

    Hayashi, Akiko; Horiuchi, Akiko; Kikuchi, Norihiko; Hayashi, Takuma; Fuseya, Chiho; Suzuki, Akihisa; Konishi, Ikuo; Shiozawa, Tanri

    2010-09-01

    Histone acetylation/deacetylation controls chromatin activity and subsequent gene transcription. Recent studies demonstrated the activation of histone deacetylases (HDACs) in various human malignancies; however, the expression and function of HDACs in ovarian tumors are not fully understood. In this study, we examined the immunohistochemical expression of HDAC1, HDAC2 and HDAC3 using tissues obtained from 115 cases of ovarian tumors and compared it with that of Ki-67 (a growth marker), p21, and E-cadherin and clinicopathological parameters. In addition, we analyzed the effect of specific siRNA for HDAC1, HDAC2 and HDAC3 on the expression of cell cycle-related molecules and E-cadherin to clarify the functional difference among the 3 HDACs. The results indicated that the immunohistochemical expression of nuclear HDAC1, HDAC2 and HDAC3 proteins increased stepwise in benign, borderline and malignant tumors. The expression of HDAC1 and HDAC2 was correlated with Ki-67 expression and that of HDAC3 was inversely correlated with E-cadherin expression. Among the HDACs examined, only HDAC1 was associated with a poor outcome, when overexpressed. Treatment with HDAC inhibitors suppressed the proliferation of ovarian cancer cells in association with apoptosis. A specific siRNA for HDAC1 significantly reduced the proliferation of ovarian carcinoma cells via downregulation of cyclin A expression, but siRNA for HDAC3 reduced the cell migration with elevated E-cadherin expression. Our results suggested that HDAC1 plays an important role in the proliferation of ovarian cancer cells, whereas HDAC3 functions in cell adhesion and migration. Therefore, specific therapeutic approaches should be considered according to the HDAC subtypes.

  7. The changing proliferation threat

    SciTech Connect

    Sopko, J.F.

    1996-12-31

    Technological advances and new adversaries with new motives have reduced the relevancy and effectiveness of the American nonproliferation strategy that was developed during the Cold War. The Cold War`s end and the breakup of the Soviet Union have created new proliferation dangers even as they have reduced others. The familiar balance of nuclear terror that linked the superpowers and their client states for nearly 50 years in a choreographed series of confrontations has given way to a much less predictable situation, where weapons of unthinkable power appear within the grasp of those more willing to use them. Rogue nations and {open_quotes}clientless{close_quotes} states, terrorist groups, religious cults, ethnic minorities, disaffected political groups, and even individuals appear to have jointed a new arms race toward mass destruction. The author describes recent events that suggest the new trends and a serious challenge to US national security.

  8. Airway epithelium stimulates smooth muscle proliferation.

    PubMed

    Malavia, Nikita K; Raub, Christopher B; Mahon, Sari B; Brenner, Matthew; Panettieri, Reynold A; George, Steven C

    2009-09-01

    Communication between the airway epithelium and stroma is evident during embryogenesis, and both epithelial shedding and increased smooth muscle proliferation are features of airway remodeling. Hence, we hypothesized that after injury the airway epithelium could modulate airway smooth muscle proliferation. Fully differentiated primary normal human bronchial epithelial (NHBE) cells at an air-liquid interface were co-cultured with serum-deprived normal primary human airway smooth muscle cells (HASM) using commercially available Transwells. In some co-cultures, the NHBE were repeatedly (x4) scrape-injured. An in vivo model of tracheal injury consisted of gently denuding the tracheal epithelium (x3) of a rabbit over 5 days and then examining the trachea by histology 3 days after the last injury. Our results show that HASM cell number increases 2.5-fold in the presence of NHBE, and 4.3-fold in the presence of injured NHBE compared with HASM alone after 8 days of in vitro co-culture. In addition, IL-6, IL-8, monocyte chemotactic protein (MCP)-1 and, more markedly, matrix metalloproteinase (MMP)-9 concentration increased in co-culture correlating with enhanced HASM growth. Inhibiting MMP-9 release significantly attenuated the NHBE-dependent HASM proliferation in co-culture. In vivo, the injured rabbit trachea demonstrated proliferation in the smooth muscle (trachealis) region and significant MMP-9 staining, which was absent in the uninjured control. The airway epithelium modulates smooth muscle cell proliferation via a mechanism that involves secretion of soluble mediators including potential smooth muscle mitogens such as IL-6, IL-8, and MCP-1, but also through a novel MMP-9-dependent mechanism.

  9. Nucleus-localized 21.5-kDa myelin basic protein promotes oligodendrocyte proliferation and enhances neurite outgrowth in coculture, unlike the plasma membrane-associated 18.5-kDa isoform.

    PubMed

    Smith, Graham S T; Samborska, Bożena; Hawley, Steven P; Klaiman, Jordan M; Gillis, Todd E; Jones, Nina; Boggs, Joan M; Harauz, George

    2013-03-01

    The classic myelin basic protein (MBP) family of central nervous system (CNS) myelin arises from transcription start site 3 of the Golli (gene of oligodendrocyte lineage) complex and comprises splice isoforms ranging in nominal molecular mass from 14 kDa to (full-length) 21.5 kDa. We have determined here a number of distinct functional differences between the major 18.5-kDa and minor 21.5-kDa isoforms of classic MBP with respect to oligodendrocyte (OLG) proliferation. We have found that, in contrast to 18.5-kDa MBP, 21.5-kDa MBP increases proliferation of early developmental immortalized N19-OLGs by elevating the levels of phosphorylated ERK1/2 and Akt1 kinases and of ribosomal protein S6. Coculture of N2a neuronal cells with N19-OLGs transfected with the 21.5-kDa isoform (or conditioned medium from), but not the 18.5-kDa isoform, caused the N2a cells to have increased neurite outgrowth and process branching complexity. These roles were dependent on subcellular localization of 21.5-kDa MBP to the nucleus and on the exon II-encoded segment, suggesting that the nuclear localization of early minor isoforms of MBP may play a crucial role in regulating and/or initiating myelin and neuronal development in the mammalian CNS.

  10. Hepatocyte proliferation induced by a single dose of a peroxisome proliferator.

    PubMed Central

    Ohmura, T.; Ledda-Columbano, G. M.; Piga, R.; Columbano, A.; Glemba, J.; Katyal, S. L.; Locker, J.; Shinozuka, H.

    1996-01-01

    In compensatory hyperplasia after partial hepatectomy or liver cell injury, hepatocyte proliferation is triggered by coordinated actions of growth factor such as hepatocyte growth factor and transforming growth factor-alpha and -beta. Initiation of hepatocyte DNA synthesis is preceded by the activation of the set of early growth response genes mediated by enhanced nuclear factor-kappa B binding to DNA. Using an experimental model to induce hepatocyte DNA synthesis in vivo by a single dose of a peroxisome proliferator, which does not induce liver cell necrosis (direct hyperplasia), we investigated whether peroxisome proliferator-induced hepatocyte proliferation involved an induction of known growth factors, an activation of early growth response genes, and nuclear factor-kappa B. A single intragastric administration of 250 mg/kg BR931 (4-chloro-6-(2,3-xylidino)-2-pyrimidinylthio-(N-beta-hydroxyethyl) acetamide) to male wistar rats induced a wave of hepatocyte DNA synthesis starting after 12 hours and peaking at approximately 24 to 36 hours. The response was dose dependent. The treatment also induced the expression of the mRNA for the peroxisomal bifunctional enzyme, one of the peroxisome-related fatty acid beta-oxidation enzymes. Pretreatment of rats with dexamethasone (2 mg/kg) inhibited both hepatocyte DNA synthesis and the induction of the peroxisomal bifunctional enzyme gene. Northern blot analyses of liver RNA during a period preceding the onset of DNA synthesis revealed no induction of hepatocyte growth factor, transforming growth factor-alpha, or tumor necrosis factor-alpha mRNAs. No induction of early growth response genes, liver regeneration factor-1, or c-myc was detected. Furthermore, gel mobility shift assays showed no enhanced nuclear factor-kappa B binding to its DNA consensus sequence after BR931 treatment, whereas control studies demonstrated a distinct increase in binding after partial hepatectomy or lead nitrate treatment. The results suggest that

  11. Modulation of keratin in adhesion, proliferation, adipogenic, and osteogenic differentiation of porcine adipose-derived stem cells.

    PubMed

    Wu, Yen-Lin; Lin, Che-Wei; Cheng, Nai-Chen; Yang, Kai-Chiang; Yu, Jiashing

    2017-01-01

    Recently, keratin attracts tremendous interest because of its intrinsic ability to interact with different cells. It has the potential to serve as a controllable extracellular matrix protein that can be used to demonstrate cell mechanism and cell-matrix interaction. However, there have been relatively few studies on the effects of keratin on stem cells. In the present work, we study the effects of human keratin on porcine adipose-derived stem cells (pASCs) and a series of selective cell lines: 3T3 fibroblasts, Madin-Darby canine kidney (MDCK) cells, and MG63 osteoblasts. Relative to un-treated culture plate, our results showed that keratin coating substrates promote cell adhesion and proliferation to above cell lines. Keratin also improved pASCs adhesion, proliferation, and enhanced cell viability. Evaluation of genetic markers showed that adipogenic and osteogenic differentiations of pASCs can be successfully induced, thus demonstrating that keratin did not influence the stemness of pASCs. Furthermore, keratin improved adipogenic differentiations of pASCs in terms of up-regulations in lipoprotein lipase, peroxisome proliferator-activated receptor gamma, and CCAAT-enhancer-binding protein alpha. The osteogenic markers type I collagen, runt-related transcription factor 2, and vitamin D receptor were also upregulated when pASCs cultured on keratin substrates. Therefore, keratin can serve as a biological derived material for surface modification and scaffold fabrication for biomedical purpose. The combination of keratin with stem cells may be a potential candidate for tissue repair in the field of regenerative medicine. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 180-192, 2017.

  12. Vertical nuclear proliferation.

    PubMed

    Sidel, Victor W

    2007-01-01

    All the nuclear-weapon states are working to develop new nuclear-weapon systems and upgrade their existing ones. Although the US Congress has recently blocked further development of small nuclear weapons and earth-penetrating nuclear weapons, the United States is planning a range of new warheads under the Reliable Replacement Warhead programme, and renewing its nuclear weapons infrastructure. The United Kingdom is spending 1 billion pounds sterling on updating the Atomic Weapons Establishment at Aldermaston, and about 20 billion pounds sterling on replacing its Vanguard submarines and maintaining its Trident warhead stockpile. The US has withdrawn from the Anti-Ballistic Missile Treaty and plans to install missile defence systems in Poland and the Czech Republic; Russia threatens to upgrade its nuclear countermeasures. The nuclear-weapon states should comply with their obligations under Article VI of the Non-Proliferation Treaty, as summarised in the 13-point plan agreed at the 2000 NPT Review Conference, and they should negotiate a Nuclear Weapons Convention.

  13. Mitogenic and chondrogenic effects of fibroblast growth factor-2 in adipose-derived mesenchymal cells

    SciTech Connect

    Chiou, Michael; Xu Yue; Longaker, Michael T. . E-mail: Longaker@stanford.edu

    2006-05-05

    Adipose-derived mesenchymal cells (AMCs) have demonstrated a great capacity for differentiating into bone, cartilage, and fat. Studies using bone marrow-derived mesenchymal cells (BMSCs) have shown that fibroblast growth factor (FGF)-2, a potent mitogenic factor, plays an important role in tissue engineering due to its effects in proliferation and differentiation for mesenchymal cells. The aim of this study was to investigate the function of FGF-2 in AMC chondrogenic differentiation and its possible contributions to cell-based therapeutics in skeletal tissue regeneration. Data demonstrated that FGF-2 significantly promoted the proliferation of AMCs and enhanced chondrogenesis in three-dimensional micromass culture. Moreover, priming AMCs with treatment of FGF-2 at 10 ng/ml demonstrated that cells underwent chondrogenic phenotypic differentiation, possibly by inducing N-Cadherin, FGF-receptor 2, and transcription factor Sox9. Our results indicated that FGF-2 potentiates chondrogenesis in AMCs, similar to its functions in BMSCs, suggesting the versatile potential applications of FGF-2 in skeletal regeneration and cartilage repair.

  14. Identification of autophosphorylation sites in eukaryotic elongation factor-2 kinase

    PubMed Central

    Pyr Dit Ruys, Sébastien; Wang, Xuemin; Smith, Ewan M.; Herinckx, Gaëtan; Hussain, Nusrat; Rider, Mark H.; Vertommen, Didier; Proud, Christopher G.

    2012-01-01

    eEF2K [eEF2 (eukaryotic elongation factor 2) kinase] phosphorylates and inactivates the translation elongation factor eEF2. eEF2K is not a member of the main eukaryotic protein kinase superfamily, but instead belongs to a small group of so-called α-kinases. The activity of eEF2K is normally dependent upon Ca2+ and calmodulin. eEF2K has previously been shown to undergo autophosphorylation, the stoichiometry of which suggested the existence of multiple sites. In the present study we have identified several autophosphorylation sites, including Thr348, Thr353, Ser366 and Ser445, all of which are highly conserved among vertebrate eEF2Ks. We also identified a number of other sites, including Ser78, a known site of phosphorylation, and others, some of which are less well conserved. None of the sites lies in the catalytic domain, but three affect eEF2K activity. Mutation of Ser78, Thr348 and Ser366 to a non-phosphorylatable alanine residue decreased eEF2K activity. Phosphorylation of Thr348 was detected by immunoblotting after transfecting wild-type eEF2K into HEK (human embryonic kidney)-293 cells, but not after transfection with a kinase-inactive construct, confirming that this is indeed a site of autophosphorylation. Thr348 appears to be constitutively autophosphorylated in vitro. Interestingly, other recent data suggest that the corresponding residue in other α-kinases is also autophosphorylated and contributes to the activation of these enzymes [Crawley, Gharaei, Ye, Yang, Raveh, London, Schueler-Furman, Jia and Cote (2011) J. Biol. Chem. 286, 2607–2616]. Ser366 phosphorylation was also detected in intact cells, but was still observed in the kinase-inactive construct, demonstrating that this site is phosphorylated not only autocatalytically but also in trans by other kinases. PMID:22216903

  15. Susceptibility of p27 kip1 knockout mice to urinary bladder carcinogenesis induced by N-butyl-N-(4-hydroxybutyl)nitrosamine may not simply be due to enhanced proliferation.

    PubMed

    Hikosaka, Atsuya; Ogawa, Kumiko; Sugiura, Satoshi; Asamoto, Makoto; Takeshita, Fumitaka; Sato, Shin-Ya; Nakanishi, Makoto; Kohri, Kenjiro; Shirai, Tomoyuki

    2008-03-15

    Deregulated proliferation is one of the fundamental characteristics of carcinogenesis. p27 is one of the most well characterized negative cell cycle regulator. In our previous study, expression of p27 protein was found to be dramatically suppressed on stimulation of cell proliferation by calculi in the rodent urinary bladder, withdrawal of the insult resulting in re-expression of p27 and regression of urothelial hyperplastic lesions. In the present study, to evaluate how loss of function impacts on urinary bladder carcinogenesis, N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN), a bladder carcinogen was given to p27 knockout mice. Males and females with either null, hetero or wild-type p27 alleles were divided into 2 groups, one given drinking water containing 0.05% BBN for 10 weeks and the other receiving distilled water, then, killed at week 20. The experiment was repeated for confirmation of the outcome. In the second experiment, performed with a larger number of animals, the incidence of urinary bladder carcinomas was significantly higher in female p27-null mice than in their wild-type counterparts. p27 deficiency also resulted in their increase of relative weights of urinary bladders and section areas of carcinomas in BBN-treated mice. Interestingly, while BrdU labeling indices generally increased with progression of mucosal proliferative lesions, from normal epithelium, through hyperplasia to carcinoma, there was no significant variation with the p27 genotype, in tumors as well as normal urothelium. These findings suggest that p27 deficient mice have elevated susceptibility to BBN-induction of urinary bladder carcinogenesis through a mechanism which might be independent of acceleration of cell cycling.

  16. Archaeal translation initiation revisited: the initiation factor 2 and eukaryotic initiation factor 2B alpha-beta-delta subunit families

    NASA Technical Reports Server (NTRS)

    Kyrpides, N. C.; Woese, C. R.

    1998-01-01

    As the amount of available sequence data increases, it becomes apparent that our understanding of translation initiation is far from comprehensive and that prior conclusions concerning the origin of the process are wrong. Contrary to earlier conclusions, key elements of translation initiation originated at the Universal Ancestor stage, for homologous counterparts exist in all three primary taxa. Herein, we explore the evolutionary relationships among the components of bacterial initiation factor 2 (IF-2) and eukaryotic IF-2 (eIF-2)/eIF-2B, i.e., the initiation factors involved in introducing the initiator tRNA into the translation mechanism and performing the first step in the peptide chain elongation cycle. All Archaea appear to posses a fully functional eIF-2 molecule, but they lack the associated GTP recycling function, eIF-2B (a five-subunit molecule). Yet, the Archaea do posses members of the gene family defined by the (related) eIF-2B subunits alpha, beta, and delta, although these are not specifically related to any of the three eukaryotic subunits. Additional members of this family also occur in some (but by no means all) Bacteria and even in some eukaryotes. The functional significance of the other members of this family is unclear and requires experimental resolution. Similarly, the occurrence of bacterial IF-2-like molecules in all Archaea and in some eukaryotes further complicates the picture of translation initiation. Overall, these data lend further support to the suggestion that the rudiments of translation initiation were present at the Universal Ancestor stage.

  17. Kruppel-like factor 2 inhibit the angiogenesis of cultured human liver sinusoidal endothelial cells through the ERK1/2 signaling pathway

    SciTech Connect

    Zeng, Xiao-Qing; Li, Na; Pan, Du-Yi; Miao, Qing; Ma, Gui-Fen; Liu, Yi-Mei; Tseng, Yu-Jen; Li, Feng; Xu, Li-Li; Chen, Shi-Yao

    2015-09-04

    Kruppel-like factor 2 (KLF2) is a crucial anti-angiogenic factor. However, its precise role in hepatic angiogenesis induced by liver sinusoidal endothelial cells (LSECs) remain unclear. This study was aimed to evaluate the effect of KLF2 on angiogenesis of LSECs and to explore the corresponding mechanism. Cultured human LSECs were infected with different lentiviruses to overexpress or suppress KLF2 expression. The CCK-8 assay, transwell migration assay and tube formation test, were used to investigate the roles of KLF2 in the proliferation, migration and vessel tube formation of LSECs, respectively. The expression and phosphorylation of ERK1/2 were detected by western blot. We discovered that the up-regulation of KLF2 expression dramatically inhibited proliferation, migration and tube formation in treated LSECs. Correspondingly, down-regulation of KLF2 expression significantly promoted proliferation, migration and tube formation in treated LSECs. Additionally, KLF2 inhibited the phosphorylation of ERK1/2 pathway, followed by the function of KLF2 in the angiogenesis of LSECs disrupted. In conclusion, KLF2 suppressed the angiogenesis of LSECs through inhibition of cell proliferation, migration, and vessel tube formation. These functions of KLF2 may be mediated through the ERK1/2 signaling pathway. - Highlights: • Overexpression of KLF2 inhibits the proliferation and migration of LSECs. • Overexpression of KLF2 inhibits the angiogenesis of LSECs. • ERK1/2 signaling pathway involved in the anti-angiogenic process of KLF2 on LSECs.

  18. Ovarian hormones enhance 2,3,7,8-tetrachlorodibenzo-p-dioxin-mediated increases in cell proliferation and preneoplastic foci in a two-stage model for rat hepatocarcinogenesis.

    PubMed

    Lucier, G W; Tritscher, A; Goldsworthy, T; Foley, J; Clark, G; Goldstein, J; Maronpot, R

    1991-03-01

    2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is a potent hepatocarcinogen in rodents. However, liver tumor incidence is increased by TCDD in female Sprague-Dawley rats but not male rats in chronic carcinogen bioassays. Our studies have investigated this finding by evaluating histological and biochemical parameters in a two-stage model for hepatocarcinogenesis in female Sprague-Dawley rats (intact and ovariectomized), using diethylnitrosamine (DEN) as the initiating agent and TCDD as the promoting agent. Increases in gamma-glutamyl transpeptidase-positive foci were greater in intact female rats than in ovariectomized (OVX) animals. For example, in intact rats receiving both DEN and TCDD, the percentage of liver occupied by gamma-glutamyl transpeptidase-positive foci was 0.37, compared to 0.08 in OVX rats. Values for intact or OVX rats receiving either DEN or TCDD only were 0.04 or less. Similar results were obtained when using placental glutathione S-transferase to detect hepatic preneoplastic lesions. Cell proliferation data, obtained using bromodeoxyuridine in osmotic minipumps, were consistent with preneoplastic foci data in that the hepatocyte labeling index was increased in DEN/TCDD intact rats but not in DEN/TCDD OVX rats. Analysis of data from individual animals revealed a strong correlation (P less than 0.01) between cell proliferation and placental glutathione S-transferase-positive foci/cm3 in liver. These findings did not reflect effects of ovariectomy on TCDD tissue distribution, since livers of OVX rats contained more TCDD than livers of intact rats, although both groups of rats received a dose of 1.4 micrograms TCDD/kg once every 2 weeks for 30 weeks. Hepatic cytochrome P-450d (IA2) was induced approximately 6-8-fold in all TCDD-treated groups, and the magnitude of induction was not influenced by ovariectomy. This cytochrome efficiently catalyzes metabolism of 17 beta-estradiol to catechol estrogens. Our data suggest that ovarian hormones (probably

  19. Nuclear localization of glutamate-cysteine ligase is associated with proliferation in head and neck squamous cell carcinoma.

    PubMed

    Dequanter, Didier; VAN DE Velde, Maureen; Bar, Isabelle; Nuyens, Vincent; Rousseau, Alexandre; Nagy, Nathalie; Vanhamme, Luc; Vanhaeverbeek, Michel; Brohée, Dany; Delrée, Paul; Boudjeltia, Karim; Lothaire, Philippe; Uzureau, Pierrick

    2016-06-01

    Glutathione (GSH) is the keystone of the cellular response toward oxidative stress. Elevated GSH content correlates with increased resistance to chemotherapy and radiotherapy of head and neck (HN) tumors. The purpose of the present cross-sectional study was to evaluate whether the expression of glutamate-cysteine ligase (GCL) accounts for the increased GSH availability observed in HN squamous cell carcinoma (SCC). For that purpose, the messenger (m)RNA levels of the modifier (M) and catalytic (C) subunits of GCL and its putative regulators (namely, nuclear factor erythroid 2-related factor 2, heme oxygenase-1 and nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor, alpha) were monitored in 35 surgical resections of untreated HNSCC. The localization of GCLM was evaluated using in situ hybridization and immunohistochemistry. GCLM expression was significantly increased in tumor samples, compared with normal mucosa, both at the mRNA and protein level (P=0.029), but the pathway of GCLM activation remains to be elucidated. Protein expression of GCLM was detected in the cytoplasm and nucleus. GCLM and the proliferation marker Ki-67 displayed a similar distribution, being both mainly expressed at the periphery of tumor lobules. The present study reported increased expression of GCL and the rate-limiting enzyme of GSH synthesis, within HNSCC. The nuclear localization of GCLM and the concomitant expression of Ki-67 suggested that the localization of GSH synthesis contributes to the protection against oxidative stress within hotspots of cell proliferation.

  20. Silencing of Y-box binding protein-1 by RNA interference inhibits proliferation, invasion, and metastasis, and enhances sensitivity to cisplatin through NF-κB signaling pathway in human neuroblastoma SH-SY5Y cells.

    PubMed

    Wang, Hong; Sun, Ruowen; Chi, Zuofei; Li, Shuang; Hao, Liangchun

    2017-04-05

    Y-box binding protein-1 (YB-1), a member of Y-box protein family binding DNA and RNA, has been proposed as a novel marker in multiple malignant tumors and found to be associated with tumor malignancy. Neuroblastoma is an embryonal tumor arising from neuroblast cells of the autonomic nervous system, which is the most common cancer diagnosed in infants. It has been reported that YB-1 is highly expressing in various human tumors including nasopharynx, thyroid, lung, breast, colon, ovary, and prostate cancers. This study aimed to investigate the functional role of YB-1 in neuroblastoma by silencing YB-1 using RNA interference (shRNA) in neuroblastoma SH-SY5Y cells. We found that silencing of YB-1 decreased the proliferation, migration, and invasion of SH-SY5Y cells. At molecular level, inhibition of YB-1 decreased the expression level of PCNA as well as MMP-2 in neuroblastoma SH-SY5Y cells. Also, we discovered that YB-1 silencing sensitized SH-SY5Y cells to cisplatin and promoted the apoptosis induced by cisplatin due to down-regulation of multidrug resistance (MDR) 1 protein via NF-κB signaling pathway. Therefore, we consider that targeting YB-1 is promising for neuroblastoma treatment and for overcoming its cisplatin resistance in the development of new neuroblastoma therapeutic strategies.

  1. Analysis of nuclear proliferation resistance reprocessing and recycling technologies

    SciTech Connect

    Patricia Paviet-Hartmann; Gary Cerefice; Marcela Stacey; Steven Bakhtiar

    2011-05-01

    The PUREX process has been progressively and continuously improved during the past three decades, and these improvements account for successful commercialization of reprocessing in a few countries. The renewed interest in nuclear energy and the international growth of nuclear electricity generation do not equate – and should not be equated -with increasing proliferation risks. Indeed, the nuclear renaissance presents a unique opportunity to enhance the culture of non-proliferation. With the recent revival of interest in nuclear technology, technical methods for prevention of nuclear proliferation are being revisited. Robust strategies to develop new advanced separation technologies are emerging worldwide for sustainability and advancement of nuclear energy with enhanced proliferation resistance. On the other hand, at this moment, there are no proliferation resistance advanced technologies. . Until now proliferation resistance as it applies to reprocessing has been focused on not separating a pure stream of weapons-usable plutonium. France, as an example, has proposed a variant of the PUREX process, the COEX TM process, which does not result on a pure plutonium product stream. A further step is to implement a process based on group extraction of actinides and fission products associated with a homogeneous recycling strategy (UNEX process in the US, GANEX process in France). Such scheme will most likely not be deployable on an industrial scale before 2030 or so because it requires intensive R&D and robust flowsheets. Finally, future generation recycling schemes will handle the used nuclear fuel in fast neutron reactors. This means that the plutonium throughput of the recycling process may increase. The need is obvious for advanced aqueous recycling technologies that are intrinsically more proliferation resistant than the commercial PUREX process. In this paper, we review the actual PUREX process along with the advanced recycling technologies that will enhance

  2. Instructive nanofibrous scaffold comprising runt-related transcription factor 2 gene delivery for bone tissue engineering.

    PubMed

    Monteiro, Nelson; Ribeiro, Diana; Martins, Albino; Faria, Susana; Fonseca, Nuno A; Moreira, João N; Reis, Rui L; Neves, Nuno M

    2014-08-26

    Inducer molecules capable of regulating mesenchymal stem cell differentiation into specific lineages have proven effective in basic science and in preclinical studies. Runt-related transcription factor 2 (RUNX2) is considered to be the central gene involved in the osteoblast phenotype induction, which may be advantageous for inducing bone tissue regeneration. This work envisions the development of a platform for gene delivery, combining liposomes as gene delivery devices, with electrospun nanofiber mesh (NFM) as a tissue engineering scaffold. pDNA-loaded liposomes were immobilized at the surface of functionalized polycaprolactone (PCL) NFM. Human bone-marrow-derived mesenchymal stem cells (hBMSCs) cultured on RUNX2-loaded liposomes immobilized at the surface of electrospun PCL NFM showed enhanced levels of metabolic activity and total protein synthesis. RUNX2-loaded liposomes immobilized at the surface of electrospun PCL NFMs induce a long-term gene expression of eGFP and RUNX2 by cultured hBMSCs. Furthermore, osteogenic differentiation of hBMSCs was also achieved by the overexpression of other osteogenic markers in medium free of osteogenic supplementation. These findings demonstrate that surface immobilization of RUNX2 plasmid onto elestrospun PCL NFM can produce long-term gene expression in vitro, which may be employed to enhance the osteoinductive properties of scaffolds used for bone tissue engineering strategies.

  3. Intermittent individual housing increases survival of newly proliferated cells.

    PubMed

    Aberg, Elin; Pham, Therese M; Zwart, Mieke; Baumans, Vera; Brené, Stefan

    2005-09-08

    In this study, we analyzed how intermittent individual housing with or without a running wheel influenced corticosterone levels and survival of newly proliferated cells in the dentate gyrus of the hippocampus. Female Balb/c mice, in standard or enhanced housing, were divided into groups that were individually housed with or without running wheels on every second day. Intermittent individual housing without, but not with, running wheels increased survival of proliferated cells in the dentate gyrus as compared with continuous group housing in standard or enhanced conditions. Thus, changes in housing conditions on every second day can, under certain circumstances, have an impact on the survival of newly proliferated cells in the dentate gyrus.

  4. Nuclear Proliferation and Grand Challenges

    ScienceCinema

    McCarthy, Kathy

    2016-07-12

    Nuclear engineer Dr. Kathy McCarthy leads systems analysis. She talks about proliferation and the grand challenges of nuclear R&D. For more information about INL energy research, visit http://www.facebook.com/idahonationallaboratory.

  5. Nuclear Proliferation and Grand Challenges

    SciTech Connect

    McCarthy, Kathy

    2009-01-01

    Nuclear engineer Dr. Kathy McCarthy leads systems analysis. She talks about proliferation and the grand challenges of nuclear R&D. For more information about INL energy research, visit http://www.facebook.com/idahonationallaboratory.

  6. Transcriptional repression of Kruppel like factor-2 by the adaptor protein p66shc

    PubMed Central

    Kumar, Ajay; Hoffman, Timothy A.; DeRicco, Jeremy; Naqvi, Asma; Jain, Mukesh K.; Irani, Kaikobad

    2009-01-01

    The adaptor protein p66shc promotes cellular oxidative stress and apoptosis. Here, we demonstrate a novel mechanistic relationship between p66shc and the kruppel like factor-2 (KLF2) transcription factor and show that this relationship has biological relevance to p66shc-regulated cellular oxidant level, as well as KLF2-induced target gene expression. Genetic knockout of p66shc in mouse embryonic fibroblasts (MEFs) stimulates activity of the core KLF2 promoter and increases KLF2 mRNA and protein expression. Similarly, shRNA-induced knockdown of p66shc increases KLF2-promoter activity in HeLa cells. The increase in KLF2-promoter activity in p66shc-knockout MEFs is dependent on a myocyte enhancing factor-2A (MEF2A)-binding sequence in the core KLF2 promoter. Short-hairpin RNA-induced knockdown of p66shc in endothelial cells also stimulates KLF2 mRNA and protein expression, as well as expression of the endothelial KLF2 target gene thrombomodulin. MEF2A protein and mRNA are more abundant in p66shc-knockout MEFs, resulting in greater occupancy of the KLF2 promoter by MEF2A. In endothelial cells, the increase in KLF2 and thrombomodulin protein by shRNA-induced decrease in p66shc expression is partly abrogated by knockdown of MEF2A. Finally, knockdown of KLF2 abolishes the decrease in the cellular reactive oxygen species hydrogen peroxide observed with knockdown of p66shc, and KLF2 overexpression suppresses cellular hydrogen peroxide levels, independent of p66shc expression. These findings illustrate a novel mechanism by which p66shc promotes cellular oxidative stress, through suppression of MEF2A expression and consequent repression of KLF2 transcription.—Kumar, A., Hoffman, T. A., DeRicco, J., Naqvi, A., Jain, M. K., Irani, K. Transcriptional repression of Kruppel like factor-2 by the adaptor protein p66shc. PMID:19696221

  7. Heparin affin regulatory peptide/pleiotrophin mediates fibroblast growth factor 2 stimulatory effects on human prostate cancer cells.

    PubMed

    Hatziapostolou, Maria; Polytarchou, Christos; Katsoris, Panagiotis; Courty, Jose; Papadimitriou, Evangelia

    2006-10-27

    Fibroblast growth factor 2 (FGF2) is a pleiotropic growth factor that has been implicated in prostate cancer formation and progression. In the present study we found that exogenous FGF2 significantly increased human prostate cancer LNCaP cell proliferation and migration. Heparin affin regulatory peptide (HARP) or pleiotrophin seems to be an important mediator of FGF2 stimulatory effects, since the latter had no effect on stably transfected LNCaP cells that did not express HARP. Moreover, FGF2, through FGF receptors (FGFRs), significantly induced HARP expression and secretion by LNCaP cells and increased luciferase activity of a reporter gene vector carrying the full-length promoter of HARP gene. Using a combination of Western blot analyses, as well as genetic and pharmacological inhibitors, we found that activation of FGFR by FGF2 in LNCaP cells leads to NAD(P)H oxidase-dependent hydrogen peroxide production, phosphorylation of ERK1/2 and p38, activation of AP-1, increased expression and secretion of HARP, and, finally, increased cell proliferation and migration. These results establish the role and the mode of activity of FGF2 in LNCaP cells and support an interventional role of HARP in FGF2 effects, providing new insights on the interplay among growth factor pathways within prostate cancer cells.

  8. In vivo injection of fibroblast growth factor-2 into the cisterna magna induces glypican-6 expression in mouse brain tissue.

    PubMed

    Salehi, Zivar

    2009-05-01

    The proteoglycans (PGs) are multifunctional macromolecules composed of a core polypeptide and a variable number of glycosaminoglycan chains. In the nervous system, PGs regulate the structural organization of the extracellular matrix (ECM) and modulate growth factor activities and cell proliferation and migration. Most cortical neurons are generated from neural precursor cells that reside in the ventricular zone of the embryonic brain. The proliferation and differentiation of neural precursor cells are regulated by various growth and neurotrophic factors. Fibroblast growth factor-2 (FGF-2) is an important mitogen for cortical neural precursor cells, and glypicans regulate the action of FGF-2 on neural precursor cells. Glypican-6 is one of the most abundant ECM molecules in the brain. In this study the effects of FGF-2 on glypican-6 expression in brain tissue have been investigated. FGF-2 was injected into the cerebrospinal fluid (CSF) through the cisterna magna of mouse pups. Using Western blotting, it was shown that the expression of glypican-6 is increased in response to infusion of FGF-2 into the CSF. The injection of anti-FGF-2 antibody into the cisterna magna decreased glypican-6 expression in brain tissue. The results from this study suggest that glypican-6 is important in regulating FGF-2 activity during cerebral cortical development.

  9. Biologic Roles of Estrogen Receptor-β and Insulin-Like Growth Factor-2 in Triple-Negative Breast Cancer

    PubMed Central

    Elshimali, Yahya; Garbán, Hermes; Elashoff, David; Vadgama, Jaydutt; Goodglick, Lee

    2015-01-01

    Triple-negative breast cancer (TNBC) occurs in 10–15% of patients yet accounts for almost half of all breast cancer deaths. TNBCs lack expression of estrogen and progesterone receptors and HER-2 overexpression and cannot be treated with current targeted therapies. TNBCs often occur in African American and younger women. Although initially responsive to some chemotherapies, TNBCs tend to relapse and metastasize. Thus, it is critical to find new therapeutic targets. A second ER gene product, termed ERβ, in the absence of ERα may be such a target. Using human TNBC specimens with known clinical outcomes to assess ERβ expression, we find that ERβ1 associates with significantly worse 5-year overall survival. Further, a panel of TNBC cell lines exhibit significant levels of ERβ protein. To assess ERβ effects on proliferation, ERβ expression in TNBC cells was silenced using shRNA, resulting in a significant reduction in TNBC proliferation. ERβ-specific antagonists similarly suppressed TNBC growth. Growth-stimulating effects of ERβ may be due in part to downstream actions that promote VEGF, amphiregulin, and Wnt-10b secretion, other factors associated with tumor promotion. In vivo, insulin-like growth factor-2 (IGF-2), along with ERβ1, is significantly expressed in TNBC and stimulates high ERβ mRNA in TNBC cells. This work may help elucidate the interplay of metabolic and growth factors in TNBC. PMID:25874233

  10. Cell Proliferation and Cytotoxicity Assays.

    PubMed

    Adan, Aysun; Kiraz, Yağmur; Baran, Yusuf

    Cell viability is defined as the number of healthy cells in a sample and proliferation of cells is a vital indicator for understanding the mechanisms in action of certain genes, proteins and pathways involved cell survival or death after exposing to toxic agents. Generally, methods used to determine viability are also common for the detection of cell proliferation. Cell cytotoxicity and proliferation assays are generally used for drug screening to detect whether the test molecules have effects on cell proliferation or display direct cytotoxic effects. Regardless of the type of cell-based assay being used, it is important to know how many viable cells are remaining at the end of the experiment. There are a variety of assay methods based on various cell functions such as enzyme activity, cell membrane permeability, cell adherence, ATP production, co-enzyme production, and nucleotide uptake activity. These methods could be basically classified into different categories: (I) dye exclusion methods such as trypan blue dye exclusion assay, (II) methods based on metabolic activity, (III) ATP assay, (IV) sulforhodamine B assay, (V) protease viability marker assay, (VI) clonogenic cell survival assay, (VII) DNA synthesis cell proliferation assays and (V) raman micro-spectroscopy. In order to choose the optimal viability assay, the cell type, applied culture conditions, and the specific questions being asked should be considered in detail. This particular review aims to provide an overview of common cell proliferation and cytotoxicity assays together with their own advantages and disadvantages, their methodologies, comparisons and intended purposes.

  11. Whole Genome Sequencing of Newly Established Pancreatic Cancer Lines Identifies Novel Somatic Mutation (c.2587G>A) in Axon Guidance Receptor Plexin A1 as Enhancer of Proliferation and Invasion

    PubMed Central

    Abisoye-Ogunniyan, Abisola; Waterfall, Joshua J.; Davis, Sean; Killian, J. Keith; Pineda, Marbin; Ray, Satyajit; McCord, Matt R.; Pflicke, Holger; Burkett, Sandra Sczerba; Meltzer, Paul S.; Rudloff, Udo

    2016-01-01

    The genetic profile of human pancreatic cancers harbors considerable heterogeneity, which suggests a possible explanation for the pronounced inefficacy of single therapies in this disease. This observation has led to a belief that custom therapies based on individual tumor profiles are necessary to more effectively treat pancreatic cancer. It has recently been discovered that axon guidance genes are affected by somatic structural variants in up to 25% of human pancreatic cancers. Thus far, however, some of these mutations have only been correlated to survival probability and no function has been assigned to these observed axon guidance gene mutations in pancreatic cancer. In this study we established three novel pancreatic cancer cell lines and performed whole genome sequencing to discover novel mutations in axon guidance genes that may contribute to the cancer phenotype of these cells. We discovered, among other novel somatic variants in axon guidance pathway genes, a novel mutation in the PLXNA1 receptor (c.2587G>A) in newly established cell line SB.06 that mediates oncogenic cues of increased invasion and proliferation in SB.06 cells and increased invasion in 293T cells upon stimulation with the receptor’s natural ligand semaphorin 3A compared to wild type PLXNA1 cells. Mutant PLXNA1 signaling was associated with increased Rho-GTPase and p42/p44 MAPK signaling activity and cytoskeletal expansion, but not changes in E-cadherin, vimentin, or metalloproteinase 9 expression levels. Pharmacologic inhibition of the Rho-GTPase family member CDC42 selectively abrogated PLXNA1 c.2587G>A-mediated increased invasion. These findings provide in-vitro confirmation that somatic mutations in axon guidance genes can provide oncogenic gain-of-function signals and may contribute to pancreatic cancer progression. PMID:26962861

  12. Whole Genome Sequencing of Newly Established Pancreatic Cancer Lines Identifies Novel Somatic Mutation (c.2587G>A) in Axon Guidance Receptor Plexin A1 as Enhancer of Proliferation and Invasion.

    PubMed

    Sorber, Rebecca; Teper, Yaroslav; Abisoye-Ogunniyan, Abisola; Waterfall, Joshua J; Davis, Sean; Killian, J Keith; Pineda, Marbin; Ray, Satyajit; McCord, Matt R; Pflicke, Holger; Burkett, Sandra Sczerba; Meltzer, Paul S; Rudloff, Udo

    2016-01-01

    The genetic profile of human pancreatic cancers harbors considerable heterogeneity, which suggests a possible explanation for the pronounced inefficacy of single therapies in this disease. This observation has led to a belief that custom therapies based on individual tumor profiles are necessary to more effectively treat pancreatic cancer. It has recently been discovered that axon guidance genes are affected by somatic structural variants in up to 25% of human pancreatic cancers. Thus far, however, some of these mutations have only been correlated to survival probability and no function has been assigned to these observed axon guidance gene mutations in pancreatic cancer. In this study we established three novel pancreatic cancer cell lines and performed whole genome sequencing to discover novel mutations in axon guidance genes that may contribute to the cancer phenotype of these cells. We discovered, among other novel somatic variants in axon guidance pathway genes, a novel mutation in the PLXNA1 receptor (c.2587G>A) in newly established cell line SB.06 that mediates oncogenic cues of increased invasion and proliferation in SB.06 cells and increased invasion in 293T cells upon stimulation with the receptor's natural ligand semaphorin 3A compared to wild type PLXNA1 cells. Mutant PLXNA1 signaling was associated with increased Rho-GTPase and p42/p44 MAPK signaling activity and cytoskeletal expansion, but not changes in E-cadherin, vimentin, or metalloproteinase 9 expression levels. Pharmacologic inhibition of the Rho-GTPase family member CDC42 selectively abrogated PLXNA1 c.2587G>A-mediated increased invasion. These findings provide in-vitro confirmation that somatic mutations in axon guidance genes can provide oncogenic gain-of-function signals and may contribute to pancreatic cancer progression.

  13. Runt-related transcription factor 2 in human colon carcinoma: a potent prognostic factor associated with estrogen receptor.

    PubMed

    Sase, Tomohiko; Suzuki, Takashi; Miura, Koh; Shiiba, Kenichi; Sato, Ikuro; Nakamura, Yasuhiro; Takagi, Kiyoshi; Onodera, Yoshiaki; Miki, Yasuhiro; Watanabe, Mika; Ishida, Kazuyuki; Ohnuma, Shinobu; Sasaki, Hiroyuki; Sato, Ryuichiro; Karasawa, Hideaki; Shibata, Chikashi; Unno, Michiaki; Sasaki, Iwao; Sasano, Hironobu

    2012-11-15

    Runt-related transcription factor 2 (RUNX2) belongs to the RUNX family of heterodimeric transcription factors, and is mainly associated with osteogenesis. Previous in vitro studies demonstrated that RUNX2 increased the cell proliferation of mouse and rat colon carcinoma cells but the status of RUNX2 has remained unknown in human colon carcinoma. Therefore, we examined clinical significance and biological functions of RUNX2 in colon carcinoma. RUNX2 immunoreactivity was examined in 157 colon carcinoma tissues using immunohistochemistry. RUNX2 immunoreactivity was evaluated as percentage of positive carcinoma cells [i.e., labeling index (LI)]. We used SW480 and DLD-1 human colon carcinoma cells, expressing estrogen receptor-β (ER) in subsequent in vitro studies. RUNX2 immunoreactivity was detected in colon carcinoma cells, and the median value of RUNX2 LI was 67%. RUNX2 LI was significantly associated with Dukes' stage, liver metastasis and ERβ status. In addition, RUNX2 LI was significantly associated with adverse clinical outcome of the colon carcinoma patients, and turned out an independent prognostic factor following multivariate analysis. Results of in vitro studies demonstrated that both SW480 and DLD-1 cells transfected with small interfering RNA against RUNX2 significantly decreased their cell proliferation, migration and invasive properties. In addition, RUNX2 mRNA level was significantly decreased by ER antagonist in these two cells. These findings all suggest that RUNX2 is a potent prognostic factor in human colon carcinoma patients through the promotion of cell proliferation and invasion properties, and is at least partly upregulated by estrogen signals through ERβ of carcinoma cells.

  14. RNA-binding protein IGF2BP3 targeting of oncogenic transcripts promotes hematopoietic progenitor proliferation

    PubMed Central

    Palanichamy, Jayanth Kumar; Tran, Tiffany M.; Howard, Jonathan M.; Contreras, Jorge R.; Fernando, Thilini R.; Sterne-Weiler, Timothy; Katzman, Sol; Toloue, Masoud; Yan, Weihong; Sanford, Jeremy R.; Rao, Dinesh S.

    2016-01-01

    Posttranscriptional control of gene expression is important for defining both normal and pathological cellular phenotypes. In vitro, RNA-binding proteins (RBPs) have recently been shown to play important roles in posttranscriptional regulation; however, the contribution of RBPs to cell specification is not well understood. Here, we determined that the RBP insulin-like growth factor 2 mRNA-binding protein 3 (IGF2BP3) is specifically overexpressed in mixed lineage leukemia–rearranged (MLL-rearranged) B-acute lymphoblastic leukemia (B-ALL), which constitutes a subtype of this malignancy associated with poor prognosis and high risk of relapse. IGF2BP3 was required for the survival of B-ALL cell lines, as knockdown led to decreased proliferation and increased apoptosis. Enforced expression of IGF2BP3 provided murine BM cells with a strong survival advantage, led to proliferation of hematopoietic stem and progenitor cells, and skewed hematopoietic development to the B cell/myeloid lineage. Cross-link immunoprecipitation and high throughput sequencing uncovered the IGF2BP3-regulated transcriptome, which includes oncogenes MYC and CDK6 as direct targets. IGF2BP3 regulated transcripts via targeting elements within 3′ untranslated regions (3′UTR), and enforced IGF2BP3 expression in mice resulted in enhanced expression of Myc and Cdk6 in BM. Together, our data suggest that IGF2BP3-mediated targeting of oncogenic transcripts may represent a critical pathogenetic mechanism in MLL-rearranged B-ALL and support IGF2BP3 and its cognate RNA-binding partners as potential therapeutic targets in this disease. PMID:26974154

  15. RNA-binding protein IGF2BP3 targeting of oncogenic transcripts promotes hematopoietic progenitor proliferation.

    PubMed

    Palanichamy, Jayanth Kumar; Tran, Tiffany M; Howard, Jonathan M; Contreras, Jorge R; Fernando, Thilini R; Sterne-Weiler, Timothy; Katzman, Sol; Toloue, Masoud; Yan, Weihong; Basso, Giuseppe; Pigazzi, Martina; Sanford, Jeremy R; Rao, Dinesh S

    2016-04-01

    Posttranscriptional control of gene expression is important for defining both normal and pathological cellular phenotypes. In vitro, RNA-binding proteins (RBPs) have recently been shown to play important roles in posttranscriptional regulation; however, the contribution of RBPs to cell specification is not well understood. Here, we determined that the RBP insulin-like growth factor 2 mRNA-binding protein 3 (IGF2BP3) is specifically overexpressed in mixed lineage leukemia-rearranged (MLL-rearranged) B-acute lymphoblastic leukemia (B-ALL), which constitutes a subtype of this malignancy associated with poor prognosis and high risk of relapse. IGF2BP3 was required for the survival of B-ALL cell lines, as knockdown led to decreased proliferation and increased apoptosis. Enforced expression of IGF2BP3 provided murine BM cells with a strong survival advantage, led to proliferation of hematopoietic stem and progenitor cells, and skewed hematopoietic development to the B cell/myeloid lineage. Cross-link immunoprecipitation and high throughput sequencing uncovered the IGF2BP3-regulated transcriptome, which includes oncogenes MYC and CDK6 as direct targets. IGF2BP3 regulated transcripts via targeting elements within 3' untranslated regions (3'UTR), and enforced IGF2BP3 expression in mice resulted in enhanced expression of Myc and Cdk6 in BM. Together, our data suggest that IGF2BP3-mediated targeting of oncogenic transcripts may represent a critical pathogenetic mechanism in MLL-rearranged B-ALL and support IGF2BP3 and its cognate RNA-binding partners as potential therapeutic targets in this disease.

  16. EDA-Containing Fibronectin Increases Proliferation of Embryonic Stem Cells

    PubMed Central

    Losino, Noelia; Waisman, Ariel; Solari, Claudia; Luzzani, Carlos; Espinosa, Darío Fernández; Sassone, Alina; Muro, Andrés F.; Miriuka, Santiago; Sevlever, Gustavo; Barañao, Lino; Guberman, Alejandra

    2013-01-01

    Embryonic stem cells (ESC) need a set of specific factors to be propagated. They can also grow in conditioned medium (CM) derived from a bovine granulosa cell line BGC (BGC-CM), a medium that not only preserves their main features but also increases ESC´s proliferation rate. The mitogenic properties of this medium were previously reported, ascribing this effect to an alternative spliced generated fibronectin isoform that contains the extra domain A (FN EDA+). Here, we investigated if the FN EDA+ isoform increased proliferation of mouse and human ES cells. We analyzed cell proliferation using conditioned media produced by different mouse embryonic fibroblast (MEF) lines genetically engineered to express FN constitutively including or excluding the EDA domain (FN EDA-), and in media supplemented with recombinant peptides containing or not the EDA. We found that the presence of EDA in the medium increased mouse and human ESC’s proliferation rate. Here we showed for the first time that this FN isoform enhances ESC’s proliferation. These findings suggest a possible conserved behavior for regulation of ES cells proliferation by this FN isoform and could contribute to improve their culturing conditions both for research and cell therapy. PMID:24244705

  17. EDA-containing fibronectin increases proliferation of embryonic stem cells.

    PubMed

    Losino, Noelia; Waisman, Ariel; Solari, Claudia; Luzzani, Carlos; Espinosa, Darío Fernández; Sassone, Alina; Muro, Andrés F; Miriuka, Santiago; Sevlever, Gustavo; Barañao, Lino; Guberman, Alejandra

    2013-01-01

    Embryonic stem cells (ESC) need a set of specific factors to be propagated. They can also grow in conditioned medium (CM) derived from a bovine granulosa cell line BGC (BGC-CM), a medium that not only preserves their main features but also increases ESC´s proliferation rate. The mitogenic properties of this medium were previously reported, ascribing this effect to an alternative spliced generated fibronectin isoform that contains the extra domain A (FN EDA(+)). Here, we investigated if the FN EDA(+) isoform increased proliferation of mouse and human ES cells. We analyzed cell proliferation using conditioned media produced by different mouse embryonic fibroblast (MEF) lines genetically engineered to express FN constitutively including or excluding the EDA domain (FN EDA(-)), and in media supplemented with recombinant peptides containing or not the EDA. We found that the presence of EDA in the medium increased mouse and human ESC's proliferation rate. Here we showed for the first time that this FN isoform enhances ESC's proliferation. These findings suggest a possible conserved behavior for regulation of ES cells proliferation by this FN isoform and could contribute to improve their culturing conditions both for research and cell therapy.

  18. Nesfatin-1 inhibits ovarian epithelial carcinoma cell proliferation in vitro

    SciTech Connect

    Xu, Yang; Pang, Xiaoyan; Dong, Mei; Wen, Fang Zhang, Yi

    2013-11-01

    Highlights: •Nesfatin-1 inhibits the proliferation and growth of HO-8910 cells by G1 phase arrest. •Nesfatin-1 enhances HO-8910 cell apoptosis. •Nesfatin-1 inhibits HO-8910 cell proliferation via mTOR and RhoA/ROCK signaling pathway. •The first report of nesfatin-1-mediated proliferation in ovarian epithelial carcinoma. -- Abstract: Nesfatin-1, an 82-amino-acid peptide derived from a 396-amino-acid precursor protein nucleobindin 2 (NUCB2), was originally identified in hypothalamic nuclei involved in the regulation of food intake. It was recently reported that nesfatin-1 is a novel depot specific adipokine preferentially produced by subcutaneous tissue, with obesity- and food deprivation-regulated expression. Although a relation between ovarian cancer mortality and obesity has been previously established, a role of nesfatin-1 in ovarian epithelial carcinoma remains unknown. The aim of the present study is to examine the effect of nesfatin-1 on ovary carcinoma cells proliferation. We found that nesfatin-1 inhibits the proliferation and growth of HO-8910 cells by G1 phase arrest, this inhibition could be abolished by nesfatin-1 neutralizing antibody. Nesfatin-1 enhances HO-8910 cell apoptosis, activation of mammalian target of rapamycin (mTOR) and RhoA/ROCK signaling pathway block the effects of nesfatin-1-induced apoptosis, therefore reverses the inhibition of HO-8910 cell proliferation by nesfatin-1. In conclusion, the present study demonstrated that nesfatin-1 can inhibit the proliferation in human ovarian epithelial carcinoma cell line HO-8910 cells through inducing apoptosis via mTOR and RhoA/ROCK signaling pathway. This study provides a novel regulatory signaling pathway of nesfatin-1-regulated ovarian epithelial carcinoma growth and may contribute to ovarian cancer prevention and therapy, especially in obese patients.

  19. 15 CFR 12.2 - Undue proliferation.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 15 Commerce and Foreign Trade 1 2011-01-01 2011-01-01 false Undue proliferation. 12.2 Section 12.2... proliferation. (a) Information as to possible undue proliferation. Any person or group, including a State or... possible existence of undue proliferation. Such communications should be in writing and include...

  20. 15 CFR 12.2 - Undue proliferation.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 15 Commerce and Foreign Trade 1 2012-01-01 2012-01-01 false Undue proliferation. 12.2 Section 12.2... proliferation. (a) Information as to possible undue proliferation. Any person or group, including a State or... possible existence of undue proliferation. Such communications should be in writing and include...

  1. 15 CFR 12.2 - Undue proliferation.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 15 Commerce and Foreign Trade 1 2014-01-01 2014-01-01 false Undue proliferation. 12.2 Section 12.2... proliferation. (a) Information as to possible undue proliferation. Any person or group, including a State or... possible existence of undue proliferation. Such communications should be in writing and include...

  2. 15 CFR 12.2 - Undue proliferation.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 15 Commerce and Foreign Trade 1 2013-01-01 2013-01-01 false Undue proliferation. 12.2 Section 12.2... proliferation. (a) Information as to possible undue proliferation. Any person or group, including a State or... possible existence of undue proliferation. Such communications should be in writing and include...

  3. 15 CFR 12.2 - Undue proliferation.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 15 Commerce and Foreign Trade 1 2010-01-01 2010-01-01 false Undue proliferation. 12.2 Section 12.2... proliferation. (a) Information as to possible undue proliferation. Any person or group, including a State or... possible existence of undue proliferation. Such communications should be in writing and include...

  4. Obestatin changes proliferation, differentiation and apoptosis of porcine preadipocytes.

    PubMed

    Tang, Shengqiu; Dong, Xiaoying; Zhang, Wei

    2014-02-01

    Obestatin, originally identified and purified from rat stomach extracts, was reported to bind to orphan G protein-coupled receptor, GPR39, and inhibit appetite and gastric motility. This study was conducted to investigate the effects of porcine obestatin on proliferation, differentiation and apoptosis of porcine preadipocytes isolated from subcutaneous fat of piglets. At indicated times of culture, morphology of preadipocytes and accumulated lipid droplets within the cells were identified by invert microscope. After treating with obestatin (0, 0.1, 1, 10 and 100nM), cell proliferation was measured by MTT method and protein expression of CCAAT/enhancer binding protein-α (C/EBPα), peroxisome proliferator-activated receptor-γ (PPARγ), Caspase-7 and Caspase-9 was determined by Western Blot, mRNA expression of GPR39 and Caspase-3 was analyzed by RT-PCR, and the activity of Caspase-3 was measured by spectrophotometric method. The results showed that obestatin had no effect on GPR39 expression, while promotes the optical density (OD) value of cells, enhanced protein expression of PPARγ and C/EBPa, decreased mRNA expression and activity of Caspase-3, and inhibited protein expression of Caspase-7 and Caspase-9 in a dose-dependent manner. These results suggested that obestatin enhances proliferation and differentiation of preadipocytes promoting PPARγ and C/EBPa expression, and inhibiting preadipocyte apoptosis by decreasing expression of Caspase-3, Caspase-7 and Caspase-9.

  5. Actin dynamics tune the integrated stress response by regulating eukaryotic initiation factor 2α dephosphorylation

    PubMed Central

    Chambers, Joseph E; Dalton, Lucy E; Clarke, Hanna J; Malzer, Elke; Dominicus, Caia S; Patel, Vruti; Moorhead, Greg; Ron, David; Marciniak, Stefan J

    2015-01-01

    Four stress-sensing kinases phosphorylate the alpha subunit of eukaryotic translation initiation factor 2 (eIF2α) to activate the integrated stress response (ISR). In animals, the ISR is antagonised by selective eIF2α phosphatases comprising a catalytic protein phosphatase 1 (PP1) subunit in complex with a PPP1R15-type regulatory subunit. An unbiased search for additional conserved components of the PPP1R15-PP1 phosphatase identified monomeric G-actin. Like PP1, G-actin associated with the functional core of PPP1R15 family members and G-actin depletion, by the marine toxin jasplakinolide, destabilised the endogenous PPP1R15A-PP1 complex. The abundance of the ternary PPP1R15-PP1-G-actin complex was responsive to global changes in the polymeric status of actin, as was its eIF2α-directed phosphatase activity, while localised G-actin depletion at sites enriched for PPP1R15 enhanced eIF2α phosphorylation and the downstream ISR. G-actin's role as a stabilizer of the PPP1R15-containing holophosphatase provides a mechanism for integrating signals regulating actin dynamics with stresses that trigger the ISR. DOI: http://dx.doi.org/10.7554/eLife.04872.001 PMID:25774599

  6. Ultrasound fails to induce proliferation of human brain and mouse endothelial cell lines

    NASA Astrophysics Data System (ADS)

    Rodemer, Claus; Jenne, Jürgen; Fatar, Marc; Hennerici, Michael G.; Meairs, Stephen

    2012-11-01

    Both in vitro and in vivo studies suggest that ultrasound (US) is capable of inducing angiogenesis. There is no information, however, on whether ultrasound can induce proliferation of brain endothelial cells. We therefore explored the angiogenic potential of ultrasound on a novel immortalised human brain endothelial cell line (hCMEC/D3) and on mouse brain microvascular endothelial cells (bEND3). Ultrasound failed to enhance cell proliferation in both cell lines at all acoustic pressures studied. Endothelial cell damage occurred at 0.24 MPa with significantly slower proliferation. Cells growing in Opticell{trade mark, serif} dishes did not show damage or reduced proliferation at these pressures.

  7. Expression profile, clinical significance, and biological function of insulin-like growth factor 2 messenger RNA-binding proteins in non-small cell lung cancer.

    PubMed

    Shi, Run; Yu, Xinnian; Wang, Yajing; Sun, Jing; Sun, Qi; Xia, Wenjie; Dong, Gaochao; Wang, Anpeng; Gao, Zhaojia; Jiang, Feng; Xu, Lin

    2017-04-01

    Insulin-like growth factor 2 messenger RNA-binding proteins have been described to associate with malignant process in many cancers. However, the role of insulin-like growth factor 2 messenger RNA-binding protein family has not been thoroughly elucidated in non-small cell lung cancer. This study was to investigate the expression profile, clinical significance, and biological function of insulin-like growth factor 2 messenger RNA-binding proteins family in non-small cell lung cancer. The expression levels of IGF2BP1-IGF2BP3 in tumor and adjacent normal tissues were determined, and association with clinicopathological features and overall survival was investigated by analyzing The Cancer Genome Atlas lung cancer database. Proliferation, migration, invasion assays, and flow-cytometry analysis were used to investigate the biological function in vitro. Insulin-like growth factor 2 messenger RNA-binding protein expression levels were significantly increased in non-small cell lung cancer compared to adjacent normal lung tissues. Chi-square test indicated that IGF2BP1 and IGF2BP3 expressions correlated with some meaningful clinical characteristics in non-small cell lung cancer. Kaplan-Meier analysis showed that high-level expression of IGF2BP1 or IGF2BP3 predicted poor overall survival in lung adenocarcinoma patients. Multivariate regression analysis showed that high level of IGF2BP3 was an independent risk factor for poor prognosis in lung adenocarcinoma patients (hazard ratio = 1.616, p = 0.017). In vitro, knockdown of IGF2BP3 inhibited lung adenocarcinoma cell proliferation by inducing cell cycle arrest and apoptosis, and undermined abilities of migration and invasion, and overexpression of IGF2BP3 could promote malignant phenotypes in lung adenocarcinoma cells. Our study revealed that expression of insulin-like growth factor 2 messenger RNA-binding proteins was widely upregulated and correlated with some certain clinicopathological features in non-small cell

  8. Nuclear Proliferation Technology Trends Analysis

    SciTech Connect

    Zentner, Michael D.; Coles, Garill A.; Talbert, Robert J.

    2005-10-04

    A process is underway to develop mature, integrated methodologies to address nonproliferation issues. A variety of methodologies (both qualitative and quantitative) are being considered. All have one thing in common, a need for a consistent set of proliferation related data that can be used as a basis for application. One approach to providing a basis for predicting and evaluating future proliferation events is to understand past proliferation events, that is, the different paths that have actually been taken to acquire or attempt to acquire special nuclear material. In order to provide this information, this report describing previous material acquisition activities (obtained from open source material) has been prepared. This report describes how, based on an evaluation of historical trends in nuclear technology development, conclusions can be reached concerning: (1) The length of time it takes to acquire a technology; (2) The length of time it takes for production of special nuclear material to begin; and (3) The type of approaches taken for acquiring the technology. In addition to examining time constants, the report is intended to provide information that could be used to support the use of the different non-proliferation analysis methodologies. Accordingly, each section includes: (1) Technology description; (2) Technology origin; (3) Basic theory; (4) Important components/materials; (5) Technology development; (6) Technological difficulties involved in use; (7) Changes/improvements in technology; (8) Countries that have used/attempted to use the technology; (9) Technology Information; (10) Acquisition approaches; (11) Time constants for technology development; and (12) Required Concurrent Technologies.

  9. A study on the role of (+)-catechin in suppression of HepG2 proliferation via caspase dependent pathway and enhancement of its in vitro and in vivo cytotoxic potential through liposomal formulation.

    PubMed

    Jain, Prateek; Kumar, Nitesh; Josyula, Venkata Rao; Jagani, Hitesh Vitthal; Udupa, N; Mallikarjuna Rao, C; Vasanth Raj, Palanimuthu

    2013-11-20

    Catechin is a known hepatoprotective and anticancer agent but has limited bioavailability. Its apoptotic signaling pathway in human hepatocellular carcinoma is vaguely explored. Thus, this study was designed to explore cytotoxicity by MTT assay, induction of apoptosis via DNA fragmentation, nuclear staining, bivariate flow cytometric analysis using annexin V- FITC and propidium iodide, cell cycle analysis and apoptotic markers by RT-PCR and western blotting in HepG2 cells. To increase the bioavailability and selectivity to cancer cells, various liposomes of catechin viz., conventional, charged and PEGylated forms were prepared by film hydration method and evaluated for cytotoxicity in vitro in HepG2 cells and in in vivo in EAC-induced liquid tumor model. Catechin and catechin liposomes inhibited the growth of HepG2 cell lines at concentrations 100-200 μg mL(-1) depending on the length of exposure. It induced apoptosis and inhibited G₂/M phase in cell cycle analysis. Catechin downregulated Bcl-2, initiated the release of cytochrome c into the cytosol and upregulated Bax, caspase-3,-9 and p53 in the HepG2 cells. Catechin and its liposomal formulation, at a dose of 200mg/kg body weight was found to be significantly (p<0.05) effective in inhibiting percentage increase in body weight and enhancing the mean survival time. Deviated hematological parameters, antioxidant parameters (superoxide dismutase, catalase and lipid peroxidation) and LFT in tumor bearing mice were found to be significantly (p<0.05) restored towards normal after treatment with catechin and its liposomes.

  10. Induction of proliferation in vitro of resting human natural killer cells

    SciTech Connect

    London, L.

    1986-01-01

    Experiments examined the cellular and humoral factors necessary to induce proliferation of purified NK cells in vitro and analyzed the phenotypic characteristics of these proliferating cells. The authors experiments demonstrated that NK cells do not proliferate in response to typical T cell mitogens or to allogeneic stimulation. However, NK cells are readily induced to proliferate in response to either natural or recombinant IL-2. The proliferative response of NK cells to IL-2 is enhanced in the presence of irradiated B lymphoblastoid ell lines. Proliferating NK cells maintain the expression of surface markers characteristic of freshly isolated NK cells which newly expressing surface activation antigens including the IL-2 and transferric receptors and the HLA-DR antigen. The majority of NK cells initiate proliferation in response to IL-2. Greater than 50 U/ml of IL-2 is necessary to induce maximal tritiated thymidine (/sup 3/H-TdR) incorporation by NK cells, and the interaction of IL-2 with the Tac IL-2 receptor is required for the maintenance of NK cell proliferation. NK cells do not proliferate in response to irradiated Daudi cells alone, which, in the presence of IL-2, may act by maintaining continuous proliferation of the cells originally responsive to IL-2. Unlike NK cells, the authors have shown that only a minor subset of T cells proliferate in response to IL-2 alone.

  11. The endogenous cannabinoid anandamide inhibits human breast cancer cell proliferation

    PubMed Central

    De Petrocellis, Luciano; Melck, Dominique; Palmisano, Antonella; Bisogno, Tiziana; Laezza, Chiara; Bifulco, Maurizio; Di Marzo, Vincenzo

    1998-01-01

    Anandamide was the first brain metabolite shown to act as a ligand of “central” CB1 cannabinoid receptors. Here we report that the endogenous cannabinoid potently and selectively inhibits the proliferation of human breast cancer cells in vitro. Anandamide dose-dependently inhibited the proliferation of MCF-7 and EFM-19 cells with IC50 values between 0.5 and 1.5 μM and 83–92% maximal inhibition at 5–10 μM. The proliferation of several other nonmammary tumoral cell lines was not affected by 10 μM anandamide. The anti-proliferative effect of anandamide was not due to toxicity or to apoptosis of cells but was accompanied by a reduction of cells in the S phase of the cell cycle. A stable analogue of anandamide (R)-methanandamide, another endogenous cannabinoid, 2-arachidonoylglycerol, and the synthetic cannabinoid HU-210 also inhibited EFM-19 cell proliferation, whereas arachidonic acid was much less effective. These cannabimimetic substances displaced the binding of the selective cannabinoid agonist [3H]CP 55,940 to EFM-19 membranes with an order of potency identical to that observed for the inhibition of EFM-19 cell proliferation. Moreover, anandamide cytostatic effect was inhibited by the selective CB1 receptor antagonist SR 141716A. Cell proliferation was arrested by a prolactin mAb and enhanced by exogenous human prolactin, whose mitogenic action was reverted by very low (0.1–0.5 μM) doses of anandamide. Anandamide suppressed the levels of the long form of the prolactin receptor in both EFM-19 and MCF-7 cells, as well as a typical prolactin-induced response, i.e., the expression of the breast cancer cell susceptibility gene brca1. These data suggest that anandamide blocks human breast cancer cell proliferation through CB1-like receptor-mediated inhibition of endogenous prolactin action at the level of prolactin receptor. PMID:9653194

  12. Proteomic Analysis of Signaling Network Regulation in Renal Cell Carcinomas with Differential Hypoxia-Inducible Factor-2α Expression

    PubMed Central

    Nagaprashantha, Lokesh Dalasanur; Talamantes, Tatjana; Singhal, Jyotsana; Guo, Jia; Vatsyayan, Rit; Rauniyar, Navin; Awasthi, Sanjay

    2013-01-01

    Background The loss of von Hippel–Lindau (VHL) protein function leads to highly vascular renal tumors characterized by an aggressive course of disease and refractoriness to chemotherapy and radiotherapy. Loss of VHL in renal tumors also differs from tumors of other organs in that the oncogenic cascade is mediated by an increase in the levels of hypoxia-inducible factor-2α (HIF2α) instead of hypoxia-inducible factor-1α (HIF1α). Methods and Principal Findings We used renal carcinoma cell lines that recapitulate the differences between mutant VHL and wild-type VHL genotypes. Utilizing a method relying on extracted peptide intensities as a label-free approach for quantitation by liquid chromatography–mass spectrometry, our proteomics study revealed regulation of key proteins important for cancer cell survival, proliferation and stress-resistance, and implicated differential regulation of signaling networks in VHL-mutant renal cell carcinoma. We also observed upregulation of cellular energy pathway enzymes and the stress-responsive mitochondrial 60-kDa heat shock protein. Finding reliance on glutaminolysis in VHL-mutant renal cell carcinoma was of particular significance, given the generally predominant dependence of tumors on glycolysis. The data have been deposited to the ProteomeXchange with identifier PXD000335. Conclusions and Significance Pathway analyses provided corroborative evidence for differential regulation of molecular and cellular functions influencing cancer energetics, metabolism and cell proliferation in renal cell carcinoma with distinct VHL genotype. Collectively, the differentially regulated proteome characterized by this study can potentially guide translational research specifically aimed at effective clinical interventions for advanced VHL-mutant, HIF2α-over-expressing tumors. PMID:23940778

  13. Proliferation resistance assessments during the design phase of a recycling facility as a means of reducing proliferation risks

    SciTech Connect

    Lindell, M.A.; Grape, S.; Haekansson, A.; Jacobsson Svaerd, S.

    2013-07-01

    The sustainability criterion for Gen IV nuclear energy systems inherently presumes the availability of efficient fuel recycling capabilities. One area for research on advanced fuel recycling concerns safeguards aspects of this type of facilities. Since a recycling facility may be considered as sensitive from a non-proliferation perspective, it is important to address these issues early in the design process, according to the principle of Safeguards By Design. Presented in this paper is a mode of procedure, where assessments of the proliferation resistance (PR) of a recycling facility for fast reactor fuel have been performed so as to identify the weakest barriers to proliferation of nuclear material. Two supplementing established methodologies have been applied; TOPS (Technological Opportunities to increase Proliferation resistance of nuclear power Systems) and PR-PP (Proliferation Resistance and Physical Protection evaluation methodology). The chosen fuel recycling facility belongs to a small Gen IV lead-cooled fast reactor system that is under study in Sweden. A schematic design of the recycling facility, where actinides are separated using solvent extraction, has been examined. The PR assessment methodologies make it possible to pinpoint areas in which the facility can be improved in order to reduce the risk of diversion. The initial facility design may then be slightly modified and/or safeguards measures may be introduced to reduce the total identified proliferation risk. After each modification of design and/or safeguards implementation, a new PR assessment of the revised system can then be carried out. This way, each modification can be evaluated and new ways to further enhance the proliferation resistance can be identified. This type of iterative procedure may support Safeguards By Design in the planning of new recycling plants and other nuclear facilities. (authors)

  14. Drosophila factor 2, an RNA polymerase II transcript release factor, has DNA-dependent ATPase activity.

    PubMed

    Xie, Z; Price, D

    1997-12-12

    Drosophila factor 2 has been identified as a component of negative transcription elongation factor (N-TEF) that causes the release of RNA polymerase II transcripts in an ATP-dependent manner (Xie, Z. and Price D. H. (1996) J. Biol. Chem. 271, 11043-11046). We show here that the transcript release activity of factor 2 requires ATP or dATP and that adenosine 5'-O-(thiotriphosphate) (ATPgammaS), adenosine 5'-(beta,gamma-imino)triphosphate (AMP-PNP), or other NTPs do not support the activity. Factor 2 demonstrated a strong DNA-dependent ATPase activity that correlated with its transcript release activity. At 20 microg/ml DNA, the ATPase activity of factor 2 had an apparent Km(ATP) of 28 microM and an estimated Kcat of 140 min-1. Factor 2 caused the release of nascent transcripts associated with elongation complexes generated by RNA polymerase II on a dC-tailed template. Therefore, no other protein cofactors are required for the transcript release activity of factor 2. Using the dC-tailed template assay, it was found that renaturation of the template was required for factor 2 function.

  15. Proliferation Vulnerability Red Team report

    SciTech Connect

    Hinton, J.P.; Barnard, R.W.; Bennett, D.E.

    1996-10-01

    This report is the product of a four-month independent technical assessment of potential proliferation vulnerabilities associated with the plutonium disposition alternatives currently under review by DOE/MD. The scope of this MD-chartered/Sandia-led study was limited to technical considerations that could reduce proliferation resistance during various stages of the disposition processes below the Stored Weapon/Spent Fuel standards. Both overt and covert threats from host nation and unauthorized parties were considered. The results of this study will be integrated with complementary work by others into an overall Nonproliferation and Arms Control Assessment in support of a Secretarial Record of Decision later this year for disposition of surplus U.S. weapons plutonium.

  16. Platelets: cell proliferation and atherosclerosis.

    PubMed

    Ross, R

    1979-04-01

    Intimal smooth muscle proliferation is the hallmark of the lesions of atherosclerosis. Endothelial injury is postulated to precede this intimal smooth muscle proliferative response, which is mediated by a potent mitogenic factor derived from adherence, aggregation, and release by platelets at sites of endothelial injury. Smooth muscle proliferation is accompanied by varying amounts of connective tissue formation and intracellular and extracellular lipid deposition, dependent upon the risk factors encountered in each patient. The platelet-derived mitogen (PF) is a stable, cationic, relatively low molecular weight (10,000-30,000) protein that has been partially purified by ion exchange chromotography and gel filtration. Less than 100 ng of PF/ml culture medium can stimulate sparse 3T3 cells or smooth muscle cells, but not endothelial cells, to undergo multiple cell divisions in the presence of 5% cell-free, plasma-derived serum. The latter contains no mitogenic activity. The interaction of the platelet mitogen and plasma-derived components, including lipoproteins, plays a critical role in smooth muscle proliferation in vitro and in vivo in the induction of the lesions of atherosclerosis.

  17. Proliferation and the former Soviet Union

    SciTech Connect

    Not Available

    1994-09-01

    The report examines the whole range of consequences for proliferation of weapons of mass destruction of the Soviet Union's breakup and describes how U.S. assistance may reduce specific proliferation risks in the former Soviet Union.

  18. Innate immune evasion mediated by the Ambystoma tigrinum virus eukaryotic translation initiation factor 2alpha homologue.

    PubMed

    Jancovich, James K; Jacobs, Bertram L

    2011-05-01

    Ranaviruses (family Iridoviridae, genus Ranavirus) are large, double-stranded DNA (dsDNA) viruses whose replication is restricted to ectothermic vertebrates. Many highly pathogenic members of the genus Ranavirus encode a homologue of the eukaryotic translation initiation factor 2α (eIF2α). Data in a heterologous vaccinia virus system suggest that the Ambystoma tigrinum virus (ATV) eIF2α homologue (vIF2αH; open reading frame [ORF] 57R) is involved in evading the host innate immune response by degrading the interferon-inducible, dsRNA-activated protein kinase, PKR. To test this hypothesis directly, the ATV vIF2αH gene (ORF 57R) was deleted by homologous recombination, and a selectable marker was inserted in its place. The ATVΔ57R virus has a small plaque phenotype and is 8-fold more sensitive to interferon than wild-type ATV (wtATV). Infection of fish cells with the ATVΔ57R virus leads to eIF2α phosphorylation, in contrast to infection with wtATV, which actively inhibits eIF2α phosphorylation. The inability of ATVΔ57R to prevent phosphorylation of eIF2α correlates with degradation of fish PKZ, an interferon-inducible enzyme that is closely related to mammalian PKR. In addition, salamanders infected with ATVΔ57R displayed an increased time to death compared to that of wtATV-infected salamanders. Therefore, in a biologically relevant system, the ATV vIF2αH gene acts as an innate immune evasion factor, thereby enhancing virus pathogenesis.

  19. Stromal cell–derived factor 2 is critical for Hsp90-dependent eNOS activation

    PubMed Central

    Siragusa, Mauro; Fröhlich, Florian; Park, Eon Joo; Schleicher, Michael; Walther, Tobias C.; Sessa, William C.

    2016-01-01

    Endothelial nitric oxide synthase (eNOS) catalyzes the conversion of l-arginine and molecular oxygen into l-citrulline and nitric oxide (NO), a gaseous second messenger that influences cardiovascular physiology and disease. Several mechanisms regulate eNOS activity and function, including phosphorylation at Ser and Thr residues and protein-protein interactions. Combining a tandem affinity purification approach and mass spectrometry, we identified stromal cell–derived factor 2 (SDF2) as a component of the eNOS macromolecular complex in endothelial cells. SDF2 knockdown impaired agonist-stimulated NO synthesis and decreased the phosphorylation of eNOS at Ser1177, a key event required for maximal activation of eNOS. Conversely, SDF2 overexpression dose-dependently increased NO synthesis through a mechanism involving Akt and calcium (induced with ionomycin), which increased the phosphorylation of Ser1177 in eNOS. NO synthesis by iNOS (inducible NOS) and nNOS (neuronal NOS) was also enhanced upon SDF2 overexpression. We found that SDF2 was a client protein of the chaperone protein Hsp90, interacting preferentially with the M domain of Hsp90, which is the same domain that binds to eNOS. In endothelial cells exposed to vascular endothelial growth factor (VEGF), SDF2 was required for the binding of Hsp90 and calmodulin to eNOS, resulting in eNOS phosphorylation and activation. Thus, our data describe a function for SDF2 as a component of the Hsp90-eNOS complex that is critical for signal transduction in endothelial cells. PMID:26286023

  20. Low and high dose UVB regulation of transcription factor NF-E2-related factor 2.

    PubMed

    Kannan, Sankaranarayanan; Jaiswal, Anil K

    2006-09-01

    Transcription factor NF-E2-related factor 2 (Nrf2) regulates antioxidant response element (ARE)-mediated expression and coordinated induction of chemoprotective proteins in response to chemical stress. In this report, we investigated Nrf2 response to low and high dose UVB irradiation. Low dose (7.5 J/m(2)) UVB exposure of mouse hepatoma, mouse keratinocyte, and human skin fibroblast cells led to the nuclear accumulation of Nrf2 and up-regulation of ARE-mediated gene expression. On the contrary, and intriguingly, high dose (20 J/m(2)) UVB exposure of cells led to the nuclear exclusion of Nrf2 and down-regulation of chemoprotective gene expression with possible implications in UVB carcinogenesis. We investigated the mechanism by which high dose UVB induced the nuclear exclusion of Nrf2. Prior treatment with nuclear export inhibitor, leptomycin B, abrogated the UVB-induced nuclear exclusion of Nrf2, indicating that the decrease of Nrf2 in the nucleus was due to the nuclear export of Nrf2. High dose UVB increased the phosphorylation of Nrf2Y568 which stimulated the nuclear export of Nrf2. Mutation of Nrf2Y568 to phenylalanine and src kinase inhibitor PP2 abrogated/reduced the UVB-induced phosphorylation of Nrf2Y568 and nuclear exclusion of Nrf2. Transfection with src family member Fyn small interfering RNA resulted in the nuclear accumulation of Nrf2 and an increase in the expression and UVB induction of ARE-mediated gene expression. UVB exposure also induced the nuclear localization of Fyn. These results suggest that high dose UVB induced the activation/nuclear localization of Fyn which led to increased phosphorylation of Nrf2Y568 and enhanced nuclear export of Nrf2. This resulted in nuclear exclusion of Nrf2 and down-regulation of ARE-mediated chemoprotective gene expression.

  1. Activity and regulation by growth factors of calmodulin-dependent protein kinase III (elongation factor 2-kinase) in human breast cancer

    PubMed Central

    Parmer, T G; Ward, M D; Yurkow, E J; Vyas, V H; Kearney, T J; Hait, W N

    1999-01-01

    Calmodulin-dependent protein kinase III (CaM kinase III, elongation factor-2 kinase) is a unique member of the Ca2+/CaM-dependent protein kinase family. Activation of CaM kinase III leads to the selective phosphorylation of elongation factor 2 (eEF-2) and transient inhibition of protein synthesis. Recent cloning and sequencing of CaM kinase III revealed that this enzyme represents a new superfamily of protein kinases. The activity of CaM kinase III is selectively activated in proliferating cells; inhibition of the kinase blocked cells in G0/G1-S and decreased viability. To determine the significance of CaM kinase III in breast cancer, we measured the activity of the kinase in human breast cancer cell lines as well as in fresh surgical specimens. The specific activity of CaM kinase III in human breast cancer cell lines was equal to or greater than that seen in a variety of cell lines with similar rates of proliferation. The specific activity of CaM kinase III was markedly increased in human breast tumour specimens compared with that of normal adjacent breast tissue. The activity of this enzyme was regulated by breast cancer mitogens. In serum-deprived MDA-MB-231 cells, the combination of insulin-like growth factor I (IGF-I) and epidermal growth factor (EGF) stimulated cell proliferation and activated CaM kinase III to activities observed in the presence of 10% serum. Inhibition of enzyme activity blocked cell proliferation induced by growth factors. In MCF-7 cells separated by fluorescence-activated cell sorting, CaM kinase III was increased in S-phase over that of other phases of the cell cycle. In summary, the activity of Ca2+/CaM-dependent protein kinase III is controlled by breast cancer mitogens and appears to be constitutively activated in human breast cancer. These results suggest that CaM kinase III may contribute an important link between growth factor/receptor interactions, protein synthesis and the induction of cellular proliferation in human breast

  2. Metformin inhibits the proliferation of benign prostatic epithelial cells

    PubMed Central

    Ge, Rongbin; Li, Jijun; Johnson, Cameron W.; Rassoulian, Cyrus; Olumi, Aria F.

    2017-01-01

    Objective Benign prostatic hyperplasia (BPH) is the most common proliferative abnormality of the prostate affecting elderly men throughout the world. Epidemiologic studies have shown that diabetes significantly increases the risk of developing BPH, although whether anti-diabetic medications preventing the development of BPH remains to be defined. We have previously found that stromally expressed insulin-like growth factor 1 (IGF-1) promotes benign prostatic epithelial cell proliferation through paracrine mechanisms. Here, we seek to understand if metformin, a first line medication for the treatment of type 2 diabetes, inhibits the proliferation of benign prostatic epithelial cells through reducing the expression of IGF-1 receptor (IGF-1R) and regulating cell cycle. Methods BPE cell lines BPH-1 and P69, murine fibroblasts3T3 and primary human prostatic fibroblasts were cultured and tested in this study. Cell proliferation and the cell cycle were analyzed by MTS assay and flow cytometry, respectively. The expression of IGF-1R was determined by western-blot and immunocytochemistry. The level of IGF-1 secretion in culture medium was measured by ELISA. Results Metformin (0.5-10mM, 6-48h) significantly inhibited the proliferation of BPH-1 and P69 cells in a dose-dependent and time-dependent manner. Treatment with metformin for 24 hours lowered the G2/M cell population by 43.24% in P69 cells and 24.22% in BPH-1 cells. On the other hand, IGF-1 (100ng/mL, 24h) stimulated the cell proliferation (increased by 28.81% in P69 cells and 20.95% in BPH-1 cells) and significantly enhanced the expression of IGF-1R in benign prostatic epithelial cells. Metformin (5mM) abrogated the proliferation of benign prostatic epithelial cells induced by IGF-1. In 3T3 cells, the secretion of IGF-1 was significantly inhibited by metformin from 574.31pg/ml to 197.61pg/ml. The conditioned media of 3T3 cells and human prostatic fibroblasts promoted the proliferation of epithelial cells and the

  3. Stem cell expansion during carcinogenesis in stem cell-depleted conditional telomeric repeat factor 2 null mutant mice.

    PubMed

    Bojovic, B; Ho, H-Y; Wu, J; Crowe, D L

    2013-10-24

    To examine the role of telomeric repeat-binding factor 2 (TRF2) in epithelial tumorigenesis, we characterized conditional loss of TRF2 expression in the basal layer of mouse epidermis. These mice exhibit some characteristics of dyskeratosis congenita, a human stem cell depletion syndrome caused by telomere dysfunction. The epidermis in conditional TRF2 null mice exhibited DNA damage response and apoptosis, which correlated with stem cell depletion. The stem cell population in conditional TRF2 null epidermis exhibited shorter telomeres than those in control mice. Squamous cell carcinomas induced in conditional TRF2 null mice developed with increased latency and slower growth due to reduced numbers of proliferating cells as the result of increased apoptosis. TRF2 null epidermal stem cells were found in both primary and metastatic tumors. Despite the low-grade phenotype of the conditional TRF2 null primary tumors, the number of metastatic lesions was similar to control cancers. Basal cells from TRF2 null tumors demonstrated extreme telomere shortening and dramatically increased numbers of telomeric signals by fluorescence in situ hybridization due to increased genomic instability and aneuploidy in these cancers. DNA damage response signals were detected at telomeres in TRF2 null tumor cells from these mice. The increased genomic instability in these tumors correlated with eightfold expansion of the transformed stem cell population compared with that in control cancers. We concluded that genomic instability resulting from loss of TRF2 expression provides biological advantages to the cancer stem cell population.

  4. Drosophila imaginal disc growth factor 2 is a trophic factor involved in energy balance, detoxification, and innate immunity

    PubMed Central

    Broz, Vaclav; Kucerova, Lucie; Rouhova, Lenka; Fleischmannova, Jana; Strnad, Hynek; Bryant, Peter J.; Zurovec, Michal

    2017-01-01

    Drosophila imaginal disc growth factor 2 (IDGF2) is a member of chitinase-like protein family (CLPs) able to induce the proliferation of imaginal disc cells in vitro. In this study we characterized physiological concentrations and expression of IDGF2 in vivo as well as its impact on the viability and transcriptional profile of Drosophila cells in vitro. We show that IDGF2 is independent of insulin and protects cells from death caused by serum deprivation, toxicity of xenobiotics or high concentrations of extracellular adenosine (Ado) and deoxyadenosine (dAdo). Transcriptional profiling suggested that such cytoprotection is connected with the induction of genes involved in energy metabolism, detoxification and innate immunity. We also show that IDGF2 is an abundant haemolymph component, which is further induced by injury in larval stages. The highest IDGF2 accumulation was found at garland and pericardial nephrocytes supporting its role in organismal defence and detoxification. Our findings provide evidence that IDGF2 is an important trophic factor promoting cellular and organismal survival. PMID:28230183

  5. Telomeric repeat-binding factor 2: a marker for survival and anti-EGFR efficacy in oral carcinoma

    PubMed Central

    Raybaud, Hélène; Sudaka, Anne; Chamorey, Emmanuel; Brolih, Sanja; Monteverde, Martino; Merlano, Marco; Nigro, Cristiana Lo; Ambrosetti, Damien; Pagès, Gilles

    2016-01-01

    Oral Squamous Cell Carcinoma (OSCC) is the most common oral cancer worldwide. Treatments including surgery, radio- and chemo-therapies mostly result in debilitating side effects. Thus, a more accurate evaluation of patients at risk of recurrence after radio/chemo treatment is important for preserving their quality of life. We assessed whether the Telomeric Repeat-binding Factor 2 (TERF2) influences tumor aggressiveness and treatment response. TERF2 is over-expressed in many cancers but its correlation to patient outcome remains controversial in OSCC. Our retrospective study on sixty-two patients showed that TERF2 overexpression has a negative impact on survival time. TERF2-dependent survival time was independent of tumor size in a multivariate analysis. In vitro, TERF2 knockdown by RNA interference had no effect on cell proliferation, migration, senescence and apoptosis. Instead, TERF2 knockdown increased the expression of cytokines implicated in inflammation and angiogenesis, except for vascular endothelial growth factor. TERF2 knockdown resulted in a decrease vascularization and growth of xenograft tumors. Finally, response to erlotinib/Tarceva and cetuximab/Erbitux treatment was increased in TRF2 knocked-down cells. Hence, TERF2 may represent an independent marker of survival for OSCC and a predictive marker for cetuximab/Erbitux and erlotinib/Tarceva efficacy. PMID:27329590

  6. Improved Technology To Prevent Nuclear Proliferation And Counter Nuclear Terrorism

    SciTech Connect

    Richardson, J; Yuldashev, B; Labov, S; Knapp, R

    2006-06-12

    As the world moves into the 21st century, the possibility of greater reliance on nuclear energy will impose additional technical requirements to prevent proliferation. In addition to proliferation resistant reactors, a careful examination of the various possible fuel cycles from cradle to grave will provide additional technical and nonproliferation challenges in the areas of conversion, enrichment, transportation, recycling and waste disposal. Radiation detection technology and information management have a prominent role in any future global regime for nonproliferation. As nuclear energy and hence nuclear materials become an increasingly global phenomenon, using local technologies and capabilities facilitate incorporation of enhanced monitoring and detection on the regional level. Radiation detection technologies are an important tool in the prevention of proliferation and countering radiological/nuclear terrorism. A variety of new developments have enabled enhanced performance in terms of energy resolution, spatial resolution, passive detection, predictive modeling and simulation, active interrogation, and ease of operation and deployment in the field. For example, various gamma ray imaging approaches are being explored to combine spatial resolution with background suppression in order to enhance sensitivity many-fold at reasonable standoff distances and acquisition times. New materials and approaches are being developed in order to provide adequate energy resolution in field use without the necessity for liquid nitrogen. Different detection algorithms enable fissile materials to be distinguished from other radioisotopes.

  7. Heparin-binding epidermal growth factor and Src family kinases in proliferation of renal epithelial cells.

    PubMed

    Zhuang, Shougang; Kinsey, Gilbert R; Rasbach, Kyle; Schnellmann, Rick G

    2008-03-01

    Our recent studies have shown that proliferation of renal proximal tubular cells (RPTC) in the absence of growth factors requires activation of the epidermal growth factor (EGF) receptor. We sought to identify the endogenous EGF receptor ligand and investigate the mechanism(s) by which RPTC proliferate in different models. RPTC expressed both pro- and cleaved forms of heparin-binding epidermal growth factor (HB-EGF) and several metalloproteinases (MMP-2, -3, -9, and ADAM10, ADAM17) that have been reported to cleave HB-EGF. Treatment of RPTC with CRM 197, an inhibitor of HB-EGF binding to the EGF receptor, or downregulation of HB-EGF with small interfering RNA inhibited RPTC proliferation following plating. Furthermore, GM6001 (pan-MMP inhibitor), tumor-necrosis factor protease inhibitor-1 (TAPI-1; MMP and ADAM17 inhibitor), and GW280264X (ADAM10 and -17 inhibitor), but not GI254023X (ADAM10 inhibitor), attenuated the proliferation after plating. Although EGF receptor activation is required for RPTC proliferation after oxidant injury, CRM197, GM6001, and TAPI-1 did not block this response. In contrast, inhibition of Src with PP1 blocked EGF receptor activation and RPTC proliferation after oxidant injury. In addition, PP1 treatment attenuated HB-EGF-enhanced RPTC proliferation. We suggest that RPTC proliferation after plating is mediated by HB-EGF produced through an autocrine/paracrine mechanism and RPTC proliferation following oxidant injury is mediated by Src without involvement of HB-EGF.

  8. Hypergravity Stimulates Osteoblast Proliferation Via Matrix-Integrin-Signaling Pathways

    NASA Technical Reports Server (NTRS)

    Vercoutere, W.; Parra, M.; Roden, C.; DaCosta, M.; Wing, A.; Damsky, C.; Holton, E.; Searby, N.; Globus, R.; Almeida, E.

    2003-01-01

    Extensive characterizations of the physiologic consequences of microgravity and gravity indicate that lack of weight-bearing may cause tissue atrophy through cellular and subcellular level mechanisms. We hypothesize that gravity is needed for the efficient transduction of cell growth and survival signals from the extra-cellular matrix (ECM) in mechanosensitive tissues. Recent work from our laboratory and from others shows that an increase of gravity increases bone cell growth and survival. We found that 50-g hypergravity stimulation increased osteoblast proliferation for cells grown on Collagen Type I and Fibronectin, but not on Laminin or uncoated plastic. This may be a tissue-specific response, because 50-g hypergravity stimulation caused no increase in proliferation for primary rat fibroblasts. These results combined with RT-PCR for all possible integrins indicate that beta1 integrin subunit may be involved. The osteoblast proliferation response on Collagen Type I was greater at 25-g than at 10-g or 50-g; 24-h duration of hypergravity was necessary to see an increase in proliferation. Survival was enhanced during hypergravity stimulation by the presence of matrix. Flow cytometry analysis indicated that cell cycle may be altered; BrdU incorporation in proliferating cells showed an increase in the number of actively dividing cells from about 60% at 1-g to over 90% at 25-g. To further investigate the molecular components involved, we applied fluorescence labeling of cytoskeletal and signaling molecules to cells after 2 to 30 minutes of hypergravity stimulation. While structural components did not appear to be altered, phosphorylation increased, indicating that signaling pathways may be activated. These data indicate that gravity mechanostimulation of osteoblast proliferation involves specific matrix-integrin signaling pathways which are sensitive to duration and g-level.

  9. Counter-proliferation and Non-proliferation: Both Needed

    NASA Astrophysics Data System (ADS)

    May, Michael

    2004-03-01

    Preventing further proliferation of nuclear weapon and nuclear weapons usable materials, and securing the weapons and materials that exist, have increased in importance with the increased urgency of the fight against international terrorism. This problem is likely to continue to increase in importance with the anticipated growth of nuclear civilian applications around the world. Recent experience in North Korea, Iraq and Iran tends to show that some combination of counterproliferation and better use of traditional, multilateral non-proliferation methods provides the best way to address this problem. Governments seeking nuclear civilian applications, particularly those that are suspicious of Western motives, must be offered in parallel an attractive way into the system should they follow its rules and an unacceptable alternative should they not. Such a combination should aim at implementing specific measures to (1) secure nuclear materials, (2) monitor dual-use facilities, (3) improve international governance of treaties and other agreements, and (4) reduce the demand for nuclear weapons. For some of the measures implementation has begun, although with less money and priority than is needed. Other measures would constitute a major departure from the way civilian nuclear activities are now carried out and remain controversial. The established nuclear powers must agree on implementation and funding of the measures suggested before there can be much progress elsewhere.

  10. Diverse FGF receptor signaling controls astrocyte specification and proliferation

    SciTech Connect

    Kang, Kyungjun; Song, Mi-Ryoung

    2010-05-07

    During CNS development, pluripotency neuronal progenitor cells give rise in succession to neurons and glia. Fibroblast growth factor-2 (FGF-2), a major signal that maintains neural progenitors in the undifferentiated state, is also thought to influence the transition from neurogenesis to gliogenesis. Here we present evidence that FGF receptors and underlying signaling pathways transmit the FGF-2 signals that regulate astrocyte specification aside from its mitogenic activity. Application of FGF-2 to cortical progenitors suppressed neurogenesis whereas treatment with an FGFR antagonist in vitro promoted neurogenesis. Introduction of chimeric FGFRs with mutated tyrosine residues into cortical progenitors and drug treatments to specifically block individual downstream signaling pathways revealed that the overall activity of FGFR rather than individual autophosphorylation sites is important for delivering signals for glial specification. In contrast, a signal for cell proliferation by FGFR was mainly delivered by MAPK pathway. Together our findings indicate that FGFR activity promotes astrocyte specification in the developing CNS.

  11. Pmp27 promotes peroxisomal proliferation

    PubMed Central

    1995-01-01

    Peroxisomes perform many essential functions in eukaryotic cells. The weight of evidence indicates that these organelles divide by budding from preexisting peroxisomes. This process is not understood at the molecular level. Peroxisomal proliferation can be induced in Saccharomyces cerevisiae by oleate. This growth substrate is metabolized by peroxisomal enzymes. We have identified a protein, Pmp27, that promotes peroxisomal proliferation. This protein, previously termed Pmp24, was purified from peroxisomal membranes, and the corresponding gene, PMP27, was isolated and sequenced. Pmp27 shares sequence similarity with the Pmp30 family in Candida boidinii. Pmp27 is a hydrophobic peroxisomal membrane protein but it can be extracted by high pH, suggesting that it does not fully span the bilayer. Its expression is regulated by oleate. The function of Pmp27 was probed by observing the phenotype of strains in which the protein was eliminated by gene disruption or overproduced by expression from a multicopy plasmid. The strain containing the disruption (3B) was able to grow on all carbon sources tested, including oleate, although growth on oleate, glycerol, and acetate was slower than wild type. Strain 3B contained peroxisomes with all of the enzymes of beta-oxidation. However, in addition to the presence of a few modestly sized peroxisomes seen in a typical thin section of a cell growing on oleate-containing medium, cells of strain 3B also contained one or two very large peroxisomes. In contrast, cells in a strain in which Pmp27 was overexpressed contained an increased number of normal-sized peroxisomes. We suggest that Pmp27 promotes peroxisomal proliferation by participating in peroxisomal elongation or fission. PMID:7721939

  12. Proliferation Resistance and the Nuclear Renaissance

    SciTech Connect

    Shea, Thomas E.; Zentner, Michael D.

    2008-05-01

    This article explores how emphasizing proliferation resistance will accomplish that goal. What does it mean for a nuclear fuel cycle to be resistant to proliferation? How can the risk of proliferation from a fuel cycle be evaluated? How has proliferation been considered in the past and how is it being considered in nuclear energy development programs today? How should proliferation concerns interact with facility safety and operations? How do proliferation concerns affect the prospects for nuclear energy in the 21st century? And finally, what is the thinking today in relation to deployment arrangements, technical measures, and R&D programs that are in place or proposed that could both decrease the risk of proliferation and ensure the successful renaissance of nuclear power.

  13. Resveratrol pretreatment attenuates injury and promotes proliferation of neural stem cells following oxygen-glucose deprivation/reoxygenation by upregulating the expression of Nrf2, HO-1 and NQO1 in vitro

    PubMed Central

    Shen, Changbo; Cheng, Wei; Yu, Pingping; Wang, Li; Zhou, Lulin; Zeng, Li; Yang, Qin

    2016-01-01

    There is considerable interest in the use of drugs and other methods for protecting implanted neural stem cells (NSCs) from the adverse environment of injured tissue for successful cell therapy. Resveratrol can modify cardiac stem cells to enhance their survival and differentiation, however, its effect and the mechanism underlying its neuroprotective effect on NSCs following stroke remain to be fully elucidated. Nuclear factor erythroid 2-related factor 2 (Nrf-2) signaling is important in antioxidative stress, and the role of Nrf-2 signaling in the enhanced neuroprotection of NSCs by resveratrol following stroke also remains to be elucidated. In the present study, NSCs were pretreated with resveratrol prior to oxygen-glucose deprivation/reoxygenation (OGD/R) in vitro. The survival, apoptosis and proliferation of the NSCs were assessed using an MTT assay, Hoechst 33258 staining of nuclei and flow cytometry, respectively. In addition, the activity of superoxide dismutase (SOD), level of malondiadehyde (MDA) and content of glutathione (GSH) were determined. The protein expressions levels of Nrf-2, NAD(P)H:quinone oxidoreductase 1 (NQO-1), and heme oxygenase 1 (HO-1) were detected using western blot analysis. It was found that resveratrol markedly enhanced NSC survival and proliferation, decreased apoptosis and the levels of MDA, and increased the activity of SOD and content of GSH in a concentration-dependent manner following OGD/R injury in vitro. In addition, the protein expression levels of Nrf2, HO-1 and NQO1 were significantly upregulated. These findings suggested that resveratrol attenuated injury and promoted proliferation of the NSCs, at least in part, by upregulating the expression of Nrf2, HO-1 and NQO1 following OGD/R injury in vitro. PMID:27573874

  14. Co-culture with periodontal ligament stem cells enhances osteogenic gene expression in de-differentiated fat cells.

    PubMed

    Tansriratanawong, Kallapat; Tamaki, Yuichi; Ishikawa, Hiroshi; Sato, Soh

    2014-10-01

    In recent decades, de-differentiated fat cells (DFAT cells) have emerged in regenerative medicine because of their trans-differentiation capability and the fact that their characteristics are similar to bone marrow mesenchymal stem cells. Even so, there is no evidence to support the osteogenic induction using DFAT cells in periodontal regeneration and also the co-culture system. Consequently, this study sought to evaluate the DFAT cells co-culture with periodontal ligament stem cells (PDLSCs) in vitro in terms of gene expression by comparing runt-related transcription factor 2 (RUNX2) and Peroxisome proliferator-activated receptor gamma 2 (PPARγ2) genes. We isolated DFAT cells from mature adipocytes and compared proliferation with PDLSCs. After co-culture with PDLSCs, we analyzed transcriptional activity implying by DNA methylation in all adipogenic gene promoters using combined bisulfite restriction analysis. We compared gene expression in RUNX2 gene with the PPARγ2 gene using quantitative RT-PCR. After being sub-cultured, DFAT cells demonstrated morphology similar to fibroblast-like cells. At the same time, PDLSCs established all stem cell characteristics. Interestingly, the co-culture system attenuated proliferation while enhancing osteogenic gene expression in RUNX2 gene. Using the co-culture system, DFAT cells could trans-differentiate into osteogenic lineage enhancing, but conversely, their adipogenic characteristic diminished. Therefore, DFAT cells and the co-culture system might be a novel cell-based therapy for promoting osteogenic differentiation in periodontal regeneration.

  15. Induction of cereblon by NF-E2-related factor 2 in neuroblastoma cells exposed to hypoxia-reoxygenation.

    PubMed

    Lee, Kyung Jin; Lee, Kwang Min; Jo, Sooyeon; Kang, Keon Wook; Park, Chul-Seung

    2010-09-03

    Cereblon is a protein encoded by the CRBN gene, which has been associated with human autosomal recessive nonsyndromic mental retardation. However, little is known about the regulation of CRBN expression. Following exposure of mouse neuroblastoma N2A cells to hypoxia/reoxygenation (H/R), mRNA and protein expression of CRBN were increased. To better understand how CRBN expression is regulated, the promoter region of the mouse CRBN gene was characterized functionally. Deletion mutations and site-directed mutagenesis led to the identification of a functional NF-E2-related factor 2 (Nrf2)-binding site. Electrophoretic mobility shift analysis indicated that Nrf2 binds to a putative binding site in the CRBN promoter. Nrf2 overexpression and tert-butylhydroquinone treatment enhanced CRBN protein expression. These results imply that Nrf2 stimulates CRBN gene transcription under H/R conditions in neuronal cells.

  16. Bone morphogenetic protein-4 strongly potentiates growth factor-induced proliferation of mammary epithelial cells

    SciTech Connect

    Montesano, Roberto Sarkoezi, Rita; Schramek, Herbert

    2008-09-12

    Bone morphogenetic proteins (BMPs) are multifunctional cytokines that elicit pleiotropic effects on biological processes such as cell proliferation, cell differentiation and tissue morphogenesis. With respect to cell proliferation, BMPs can exert either mitogenic or anti-mitogenic activities, depending on the target cells and their context. Here, we report that in low-density cultures of immortalized mammary epithelial cells, BMP-4 did not stimulate cell proliferation by itself. However, when added in combination with suboptimal concentrations of fibroblast growth factor (FGF)-2, FGF-7, FGF-10, epidermal growth factor (EGF) or hepatocyte growth factor (HGF), BMP-4 potently enhanced growth factor-induced cell proliferation. These results reveal a hitherto unsuspected interplay between BMP-4 and growth factors in the regulation of mammary epithelial cell proliferation. We suggest that the ability of BMP-4 to potentiate the mitogenic activity of multiple growth factors may contribute to mammary gland ductal morphogenesis as well as to breast cancer progression.

  17. Negative regulators of cell proliferation

    NASA Technical Reports Server (NTRS)

    Johnson, T. C.; Spooner, B. S. (Principal Investigator)

    1994-01-01

    Cell proliferation is governed by the influence of both mitogens and inhibitors. Although cell contact has long been thought to play a fundamental role in cell cycling regulation, and negative regulators have long been suspected to exist, their isolation and purification has been complicated by a variety of technical difficulties. Nevertheless, over recent years an ever-expanding list of putative negative regulators have emerged. In many cases, their biological inhibitory activities are consistent with density-dependent growth inhibition. Most likely their interactions with mitogenic agents, at an intracellular level, are responsible for either mitotic arrest or continued cell cycling. A review of naturally occurring cell growth inhibitors is presented with an emphasis on those factors shown to be residents of the cell surface membrane. Particular attention is focused on a cell surface sialoglycopeptide, isolated from intact bovine cerebral cortex cells, which has been shown to inhibit the proliferation of an unusually wide range of target cells. The glycopeptide arrest cells obtained from diverse species, both fibroblasts and epithelial cells, and a broad variety of transformed cells. Signal transduction events and a limited spectrum of cells that are refractory to the sialoglycopeptide have provided insight into the molecular events mediated by this cell surface inhibitor.

  18. Gas Centrifuges and Nuclear Proliferation

    SciTech Connect

    Albright, David

    2004-09-15

    Gas centrifuges have been an ideal enrichment method for a wide variety of countries. Many countries have built gas centrifuges to make enriched uranium for peaceful nuclear purposes. Other countries have secretly sought centrifuges to make highly enriched uranium for nuclear weapons. In more recent times, several countries have secretly sought or built gas centrifuges in regions of tension. The main countries that have been of interest in the last two decades have been Pakistan, Iraq, Iran, and North Korea. Currently, most attention is focused on Iran, Pakistan, and North Korea. These states did not have the indigenous abilities to make gas centrifuges, focusing instead on illicit and questionable foreign procurement. The presentation covered the following main sections: Spread of centrifuges through illicit procurement; Role of export controls in stopping proliferation; Increasing the transparency of gas centrifuge programs in non-nuclear weapon states; and, Verified dismantlement of gas centrifuge programs. Gas centrifuges are important providers of low enriched uranium for civil nuclear power reactors. They also pose special nuclear proliferation risks. We all have special responsibilities to prevent the spread of gas centrifuges into regions of tension and to mitigate the consequences of their spread into the Middle East, South Asia, and North Asia.

  19. Inflammation and Proliferation Act Together to Mediate Intestinal Cell Fusion

    PubMed Central

    Swain, John R.; Wong, Melissa H.

    2009-01-01

    Cell fusion between circulating bone marrow-derived cells (BMDCs) and non-hematopoietic cells is well documented in various tissues and has recently been suggested to occur in response to injury. Here we illustrate that inflammation within the intestine enhanced the level of BMDC fusion with intestinal progenitors. To identify important microenvironmental factors mediating intestinal epithelial cell fusion, we performed bone marrow transplantation into mouse models of inflammation and stimulated epithelial proliferation. Interestingly, in a non-injury model or in instances where inflammation was suppressed, an appreciable baseline level of fusion persisted. This suggests that additional mediators of cell fusion exist. A rigorous temporal analysis of early post-transplantation cellular dynamics revealed that GFP-expressing donor cells first trafficked to the intestine coincident with a striking increase in epithelial proliferation, advocating for a required fusogenic state of the host partner. Directly supporting this hypothesis, induction of augmented epithelial proliferation resulted in a significant increase in intestinal cell fusion. Here we report that intestinal inflammation and epithelial proliferation act together to promote cell fusion. While the physiologic impact of cell fusion is not yet known, the increased incidence in an inflammatory and proliferative microenvironment suggests a potential role for cell fusion in mediating the progression of intestinal inflammatory diseases and cancer. PMID:19657387

  20. Proliferation Resistance Evaluation of ACR-1000 Fuel with Minor Actinides

    SciTech Connect

    Gray S. Chang

    2008-09-01

    The Global Nuclear Energy Partnership (GNEP) program is to significantly advance the science and technology of nuclear energy systems and to enhance the spent fuel proliferation resistance. It consists of both innovative nuclear reactors and innovative research in separation and transmutation. The merits of nuclear energy are high-density energy, with low environmental impacts (i.e. almost zero greenhouse gas emission). Planned efforts involve near-term and intermediate-term improvements in fuel utilization and recycling in current light water reactors (LWRs) as well as the longer-term development of new nuclear energy systems that offer much improved fuel utilization and proliferation resistance, along with continued advances in operational safety. For future advanced nuclear systems, minor actinides (MA) are viewed more as a resource to be recycled, and transmuted to less hazardous and possibly more useful forms, rather than simply disposed of as a waste stream in an expensive repository facility. MAs can play a much larger part in the design of advanced systems and fuel cycles, not only as additional sources of useful energy, but also as direct contributors to the reactivity control of the systems into which they are incorporated. In this work, an Advanced CANDU Reactor (ACR) fuel unit lattice cell model with 43 UO2 fuel rods will be used to investigate the effectiveness of a Minor Actinide Reduction Approach (MARA) for enhancing proliferation resistance and improving the fuel cycle performance. The main MARA objective is to increase the 238Pu / Pu isotope ratio by using the transuranic nuclides (237Np and 241Am) in the high burnup fuel and thereby increase the proliferation resistance even for a very low fuel burnup. As a result, MARA is a very effective approach to enhance the proliferation resistance for the on power refueling ACR system nuclear fuel. The MA transmutation characteristics at different MA loadings were compared and their impact on neutronics

  1. Species and strain sensitivity to the induction of peroxisome proliferation by chloroacetic acids.

    PubMed

    DeAngelo, A B; Daniel, F B; McMillan, L; Wernsing, P; Savage, R E

    1989-11-01

    B6C3F1 mice and Sprague-Dawley rats were provided drinking water containing 6-31 mM (1-5 g/liter) trichloroacetic acid (TCA), 8-39 mM (1-5 g/liter) dichloroacetic acid (DCA), or 11-32 mM (1-3 g/liter) monochloroacetic acid (MCA) for 14 days. TCA and DCA, but not MCA, increased the mouse relative liver weight in a dose-dependent manner. Rat liver weights were not altered by TCA or DCA treatment, but were depressed by MCA. Hepatic peroxisome proliferation was demonstrated by (1) increased palmitoyl-CoA oxidase and carnitine acetyl transferase activities, (2) appearance of a peroxisome proliferation-associated protein, and (3) morphometric analysis of electron micrographs. Mouse peroxisome proliferation was enhanced in a dose-dependent manner by both TCA and DCA, but only the high DCA concentration (39 mM) increased rat liver peroxisome proliferation. MCA was ineffective in both species. Three other mouse strains (Swiss-Webster, C3H, and C57BL/6) and two strains of rat (F344 and Osborne-Mendel) were examined for sensitivity to TCA. TCA (12 and 31 mM) effectively enhanced peroxisome proliferation in all mouse strains, especially the C57BL/6. A more modest enhancement in the Osborne-Mendel (288%) and F344 rat (167%) was seen. Dosing F344 rats with 200 mg/kg TCA in water or corn oil for 10 days increased peroxisome proliferation 179 and 278%, respectively, above the vehicle controls. These studies demonstrate that the mouse is more sensitive than the rat with respect to the enhancement of liver peroxisome proliferation by TCA and DCA and suggest that if peroxisome proliferation is critical for the induction of hepatic cancer by TCA and DCA, then the rat should be less sensitive or refractory to tumor induction.

  2. The administration`s non-proliferation and export control policy

    SciTech Connect

    1993-11-01

    On September 27, during his speech to the United Nations, President Bill Clinton outlined his administration`s arm control policies, urging tighter restraints on international export control policies and measures to enhance nuclear non-proliferation. That same day, the White House released a fact sheet summarizing the framework for U.S. efforts to prevent proliferation of weapons of mass destruction and missiles that deliver them.

  3. Nerve growth factor modulate proliferation of cultured rabbit corneal endothelial cells and epithelial cells.

    PubMed

    Li, Xinyu; Li, Zhongguo; Qiu, Liangxiu; Zhao, Changsong; Hu, Zhulin

    2005-01-01

    In order to investigate the effect of nerve growth factor (NGF) on the proliferation of rabbit corneal endothelial cells and epithelial cells, the in vitro cultured rabbit corneal endothelial cells and epithelial cells were treated with different concentrations of NGF. MTT assay was used to examine the clonal growth and proliferation of the cells by determining the absorbency values at 570 nm. The results showed that NGF with three concentrations ranging from 5 U/mL to 500 U/mL enhanced the proliferation of rabbit corneal endothelial cells in a concentration-dependent manner. 50 U/mL and 500 U/mL NGF got more increase of proliferation than that of 5 U/mL NGF did. Meanwhile, 50 U/mL and 500 U/mL NGF could promote the proliferation of the rabbit corneal epithelial cells significantly in a concentration-dependent manner. However, 5 U/mL NGF did not enhance the proliferation of epithelial cells. It was suggested that exogenous NGF can stimulate the proliferation of both rabbit corneal endothelial and epithelial cells, but the extent of modulation is different.

  4. Control of cell proliferation in human glioma by glucocorticoids.

    PubMed

    Freshney, R I; Sherry, A; Hassanzadah, M; Freshney, M; Crilly,