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Sample records for proliferation phagocytic activity

  1. Ion channel signaling influences cellular proliferation and phagocyte activity during axolotl tail regeneration.

    Science.gov (United States)

    Franklin, Brandon M; Voss, S Randal; Osborn, Jeffrey L

    2017-08-01

    Little is known about the potential for ion channels to regulate cellular behaviors during tissue regeneration. Here, we utilized an amphibian tail regeneration assay coupled with a chemical genetic screen to identify ion channel antagonists that altered critical cellular processes during regeneration. Inhibition of multiple ion channels either partially (anoctamin1/Tmem16a, anoctamin2/Tmem16b, K V 2.1, K V 2.2, L-type Ca V channels and H/K ATPases) or completely (GlyR, GABA A R, K V 1.5 and SERCA pumps) inhibited tail regeneration. Partial inhibition of tail regeneration by blocking the calcium activated chloride channels, anoctamin1&2, was associated with a reduction of cellular proliferation in tail muscle and mesenchymal regions. Inhibition of anoctamin 1/2 also altered the post-amputation transcriptional response of p44/42 MAPK signaling pathway genes, including decreased expression of erk1/erk2. We also found that complete inhibition via voltage gated K + channel blockade was associated with diminished phagocyte recruitment to the amputation site. The identification of H + pumps as required for axolotl tail regeneration supports findings in Xenopus and Planaria models, and more generally, the conservation of ion channels as regulators of tissue regeneration. This study provides a preliminary framework for an in-depth investigation of the mechanistic role of ion channels and their potential involvement in regulating cellular proliferation and other processes essential to wound healing, appendage regeneration, and tissue repair. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Effect of detonation nanodiamonds on phagocyte activity.

    Science.gov (United States)

    Karpukhin, Alexey V; Avkhacheva, Nadezhda V; Yakovlev, Ruslan Yu; Kulakova, Inna I; Yashin, Valeriy A; Lisichkin, Georgiy V; Safronova, Valentina G

    2011-07-01

    Detonation ND (nanodiamond) holds much promise for biological studies and medical applications. Properties like size of particles, inclination for modification of their surface and unambiguous biocompatibility are crucial. Of prime importance is interaction between ND and immune cells, which supervise foreign intrusion into an organism and eliminate it. Neutrophils are more reactive in inflammatory response implementing cytotoxical arsenal including ROS (reactive oxygen species). The aim of the work was to estimate the ability of two ND samples (produced by Diamond Center and PlasmaChem) to keep the vitality of neutrophils from the inflammatory site. The ability of cells to generate ROS in the presence of ND particles is considered as indicating their biocompatibility. IR spectra and size of particles in the samples were characterized. Acid modification of ND was carried out to get the luminescent form. In the biological aspect, ND demonstrated up or down action, depending on the concentration, time and conditions of activation of cells. Weak action of ND in whole blood was obtained possibly owing to the ND adsorbed plasma proteins, which mask active functional groups to interact with the cell membrane. ND did not influence the viability of isolated inflammatory neutrophils in low and moderate concentrations and suppressed it in high concentrations (≥1 g/l). Addition of ND to the cell suspension initiated concentration-dependent reaction to produce ROS similar to respiratory burst. ND up-regulated response to bacterial formylpeptide, but up- and down-modified (low or high concentrations, accordingly) response to such bacterial agents as OZ (opsonized zymosan), which neutrophils swallow up by oxygen-dependent phagocytosis. Localization of the particles on the cell surface as into the cells was identified by monitoring the intrinsic fluorescence of oxidized ND. The various mechanisms that could account for penetration of ND particles into the cell are discussed

  3. Uptake and intracellular activity of AM-1155 in phagocytic cells.

    Science.gov (United States)

    Yamamoto, T; Kusajima, H; Hosaka, M; Fukuda, H; Oomori, Y; Shinoda, H

    1996-01-01

    The uptake and intracellular activity of AM-1155 in murine J774.1 macrophages and human polymorphonuclear leukocytes were investigated. AM-1155 penetrated phagocytic cells rapidly and reversibly, although the penetration process was not affected by metabolic inhibitors such as sodium fluoride, cyanide m-chlorophenylhydrazone, or ouabain or by nucleoside transport system inhibitors such as adenosine. The intracellular concentration-to-extracellular concentration ratio of AM-1155 in both cell types of phagocytes ranged from 5 to 7. These ratios were almost equal to those for sparfloxacin. The intracellular activity of AM-1155 in J774.1 macrophages, examined with Staphylococcus aureus 209P as a test bacterium, was dependent on the extracellular concentration. AM-1155 at a concentration of 1 microgram/ml reduced the number of viable cells of S. aureus ingested by more than 90%. The intracellular activity of AM-1155 was more potent than those of sparfloxacin, ofloxacin, ciprofloxacin, flomoxef, and erythromycin. These results suggest that the potent intracellular activity of AM-1155 might mainly be due to the high intracellular concentration and its potent in vitro activity. PMID:9124835

  4. High content analysis of phagocytic activity and cell morphology with PuntoMorph

    DEFF Research Database (Denmark)

    Al-Ali, Hassan; Gao, Han; Dalby-Hansen, Camilla

    2017-01-01

    methods for quantifying phagocytic activity in multiple dimensions including speed, accuracy, and resolution. Conclusions We provide a framework to facilitate the development of high content assays suitable for drug screening. For convenience, we implemented our algorithm in a standalone software package...... with image-based quantification of phagocytic activity. New method We present a robust algorithm and cell-based assay system for high content analysis of phagocytic activity. The method utilizes fluorescently labeled beads as a phagocytic substrate with defined physical properties. The algorithm employs...... content screening. Results We tested our assay system using microglial cultures. Our results recapitulated previous findings on the effects of microglial stimulation on cell morphology and phagocytic activity. Moreover, our cell-level analysis revealed that the two phenotypes associated with microglial...

  5. Intracellular glutathione status regulates mouse bone marrow monocyte-derived macrophage differentiation and phagocytic activity

    International Nuclear Information System (INIS)

    Kim, Jin-Man; Kim, Hyunsoo; Kwon, Soon Bok; Lee, Soo Young; Chung, Sung-Chang; Jeong, Dae-Won; Min, Byung-Moo

    2004-01-01

    Although a redox shift can regulate the development of cells, including proliferation, differentiation, and survival, the role of the glutathione (GSH) redox status in macrophage differentiation remains unclear. In order to elucidate the role of a redox shift, macrophage-like cells were differentiated from the bone marrow-derived monocytes that were treated with a macrophage colony stimulating factor (M-CSF or CSF-1) for 3 days. The macrophagic cells were characterized by a time-dependent increase in three major symptoms: the number of phagocytic cells, the number of adherent cells, and the mRNA expression of c-fms, a M-CSF receptor that is one of the macrophage-specific markers and mediates development signals. Upon M-CSF-driven macrophage differentiation, the GSH/GSSG ratio was significantly lower on day 1 than that observed on day 0 but was constant on days 1-3. To assess the effect of the GSH-depleted and -repleted status on the differentiation and phagocytosis of the macrophages, GSH depletion by BSO, a specific inhibitor of the de novo GSH synthesis, inhibited the formation of the adherent macrophagic cells by the down-regulation of c-fms, but did not affect the phagocytic activity of the macrophages. To the contrary, GSH repletion by the addition of NAC, which is a GSH precursor, or reduced GSH in media had no effect on macrophage differentiation, and led to a decrease in the phagocytic activity. Furthermore, we observed that there is checkpoint that is capable of releasing from the inhibition of the formation of the adherent macrophagic cells according to GSH depletion by BSO. Summarizing, these results indicate that the intracellular GSH status plays an important role in the differentiation and phagocytosis of macrophages

  6. Effects of Levamisole on Phagocytic Activity of Rainbow Trout (Oncorhynchus mykiss W.

    Directory of Open Access Journals (Sweden)

    U. Ispir

    2007-01-01

    Full Text Available In this study, activation of phagocytic cells was examined in rainbow trout (Oncorhynchus mykiss W. exposed to 1, 5 and 10 μg ml-1 concentrations of levamisole solution. For this purpose, blood samples were taken from fish on days 1, 7 and 14 of exposure. Potential killing activity was determined by measuring oxidative radical production and phagocytic activity of neutrophils and superoxide anion production of phagocytic cells against Y. ruckeri. The activity of phagocytic cells in fish exposed to each of three concentrations was found higher than that in controls and the differences were statistically significant (p p -1 concentration of levamisole solution was determined on day 7, it was observed that all indicators increased on day 14 of exposure. The present results suggest that the application of levamisole in fish farms could increase non-specific immunity and resistance to infection of fish and offer economics benefits.

  7. Ultrastuctural study of the phagocytic activities of splenic ...

    African Journals Online (AJOL)

    AJB SERVER

    Direct phagocytic reaction of cells in the presence of an antigen is therefore very important in immunity. Key words: ... The main lymphoid organs of fish are the thymus, the ... The innate (non-specific) immunity is thought to have a major role in ...

  8. Phagocytic and bactericidal activities of leukocytes in whole blood from atomic bomb survivors

    International Nuclear Information System (INIS)

    Sasagawa, S.; Yoshimoto, Y.; Toyota, E.; Neriishi, S.; Yamakido, M.; Matsuo, M.; Hosoda, Y.; Finch, S.C.

    1990-01-01

    This study evaluated the phagocytic and bactericidal activities of peripheral blood leukocytes from Hiroshima and Nagasaki atomic bomb survivors for Staphylococcus aureus. The data were analyzed by multiple linear regression for age, sex, radiation exposure, city of exposure, and neutrophil counts. No significant radiation effect was observed for either blood phagocytic or bactericidal activities. The only significant variable for these functions was the neutrophil count

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

    Energy Technology Data Exchange (ETDEWEB)

    Barbers, R.G.; Evans, M.J.; Gong, H. Jr.; Tashkin, D.P. (Univ. of California-Los Angeles School of Medicine (USA))

    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.

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

    International Nuclear Information System (INIS)

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

    1991-01-01

    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 [ 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 [ 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 [ 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

  11. Modulation of rat blood phagocyte activity by serotonin

    Czech Academy of Sciences Publication Activity Database

    Okénková, Kateřina; Lojek, Antonín; Kubala, Lukáš; Číž, Milan

    2007-01-01

    Roč. 101, č. 14 (2007), s245-s246 E-ISSN 1213-7103. [Mezioborová česko-slovenská toxikologická konference /12./. Praha, 11.06.2007-13.06.2007] R&D Projects: GA ČR(CZ) GA524/04/0897 Institutional research plan: CEZ:AV0Z50040507; CEZ:AV0Z50040702 Keywords : phagocytes * serotonin * reactive oxygen species Subject RIV: BO - Biophysics

  12. Blood phagocyte activity after race training sessions in Thoroughbred and Arabian horses.

    Science.gov (United States)

    Cywinska, Anna; Szarska, Ewa; Degorski, Andrzej; Guzera, Maciej; Gorecka, Renata; Strzelec, Katarzyna; Kowalik, Sylwester; Schollenberger, Antoni; Winnicka, Anna

    2013-10-01

    Intensive exercise and exertion during competition promote many changes that may result in the impairment of immunity and increased susceptibility to infections. The aim of this study was to evaluate the activity of "the first line of defense": neutrophils and monocytes in racing Thoroughbred and Arabian horses after routine training sessions. Twenty-three (12 Thoroughbred and 11 Arabian) horses were examined. Routine haematological (number of red blood cells - RBC, haemoglobin concentration - HGB, haematocrit - HCT, total number of white blood cells - WBC), biochemical (creatine phosphokinase activity - CPK and total protein concentration - TP) parameters, cortisol concentration as well as phagocytic and oxidative burst activity of neutrophils and monocytes were determined. The values of basic parameters and the activity of phagocytes differed between breeds and distinct patterns of exercise-induced changes were observed. The training sessions did not produce the decrease in phagocyte activity that might lead to the suppression of immunity. Copyright © 2013 Elsevier Ltd. All rights reserved.

  13. High content analysis of phagocytic activity and cell morphology with PuntoMorph.

    Science.gov (United States)

    Al-Ali, Hassan; Gao, Han; Dalby-Hansen, Camilla; Peters, Vanessa Ann; Shi, Yan; Brambilla, Roberta

    2017-11-01

    Phagocytosis is essential for maintenance of normal homeostasis and healthy tissue. As such, it is a therapeutic target for a wide range of clinical applications. The development of phenotypic screens targeting phagocytosis has lagged behind, however, due to the difficulties associated with image-based quantification of phagocytic activity. We present a robust algorithm and cell-based assay system for high content analysis of phagocytic activity. The method utilizes fluorescently labeled beads as a phagocytic substrate with defined physical properties. The algorithm employs statistical modeling to determine the mean fluorescence of individual beads within each image, and uses the information to conduct an accurate count of phagocytosed beads. In addition, the algorithm conducts detailed and sophisticated analysis of cellular morphology, making it a standalone tool for high content screening. We tested our assay system using microglial cultures. Our results recapitulated previous findings on the effects of microglial stimulation on cell morphology and phagocytic activity. Moreover, our cell-level analysis revealed that the two phenotypes associated with microglial activation, specifically cell body hypertrophy and increased phagocytic activity, are not highly correlated. This novel finding suggests the two phenotypes may be under the control of distinct signaling pathways. We demonstrate that our assay system outperforms preexisting methods for quantifying phagocytic activity in multiple dimensions including speed, accuracy, and resolution. We provide a framework to facilitate the development of high content assays suitable for drug screening. For convenience, we implemented our algorithm in a standalone software package, PuntoMorph. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Whole-blood phagocytic and bactericidal activities of atomic bomb survivors, Hiroshima and Nagasaki

    International Nuclear Information System (INIS)

    Sasagawa, Sumiko; Yoshimoto, Yasuhiko; Toyota, Emiko; Neriishi, Shotaro; Yamakido, Michio; Matsuo, Miyo; Hosoda, Yutaka; Finch, S.C.

    1989-04-01

    This in vitro study evaluated the phagocytic and bactericidal activities of leukocytes in aliquots of whole blood from Hiroshima and Nagasaki atomic bomb survivors for Staphylococcus aureus. The data were analyzed by multiple linear regression. Any significant effects of exposure to A-bomb radiation could not be detected for both phagocytic and bactericidal activities of whole blood from A-bomb survivors. In addition, there were no significant effects of age categories, sex or city, except in neutrophil counts. (J.P.N.)

  15. Plasminogen activator inhibitor type 1 regulates microglial motility and phagocytic activity

    Directory of Open Access Journals (Sweden)

    Jeon Hyejin

    2012-06-01

    Full Text Available Abstract Background Plasminogen activator inhibitor type 1 (PAI-1 is the primary inhibitor of urokinase type plasminogen activators (uPA and tissue type plasminogen activators (tPA, which mediate fibrinolysis. PAI-1 is also involved in the innate immunity by regulating cell migration and phagocytosis. However, little is known about the role of PAI-1 in the central nervous system. Methods In this study, we identified PAI-1 in the culture medium of mouse mixed glial cells by liquid chromatography and tandem mass spectrometry. Secretion of PAI-1 from glial cultures was detected by ELISA and western blotting analysis. Cell migration was evaluated by in vitro scratch-wound healing assay or Boyden chamber assay and an in vivo stab wound injury model. Phagocytic activity was measured by uptake of zymosan particles. Results The levels of PAI-1 mRNA and protein expression were increased by lipopolysaccharide and interferon-γ stimulation in both microglia and astrocytes. PAI-1 promoted the migration of microglial cells in culture via the low-density lipoprotein receptor-related protein (LRP 1/Janus kinase (JAK/signal transducer and activator of transcription (STAT1 axis. PAI-1 also increased microglial migration in vivo when injected into mouse brain. PAI-1-mediated microglial migration was independent of protease inhibition, because an R346A mutant of PAI-1 with impaired PA inhibitory activity also promoted microglial migration. Moreover, PAI-1 was able to modulate microglial phagocytic activity. PAI-1 inhibited microglial engulfment of zymosan particles in a vitronectin- and Toll-like receptor 2/6-dependent manner. Conclusion Our results indicate that glia-derived PAI-1 may regulate microglial migration and phagocytosis in an autocrine or paracrine manner. This may have important implications in the regulation of brain microglial activities in health and disease.

  16. The HIV-1 Nef protein and phagocyte NADPH oxidase activation

    DEFF Research Database (Denmark)

    Vilhardt, Frederik; Plastre, Olivier; Sawada, Makoto

    2002-01-01

    of Rac by Clostridium difficile toxin B abolished the Nef effect. (ii) The fraction of activated Rac1 was increased in Nef-transduced cells, and (iii) the dominant positive Rac1(V12) mutant mimicked the effect of Nef. These results are to our knowledge the first analysis of the effect of Rac activation...

  17. Cellular immune responses and phagocytic activity of fishes exposed to pollution of volcano mud.

    Science.gov (United States)

    Risjani, Yenny; Yunianta; Couteau, Jerome; Minier, Christophe

    2014-05-01

    Since May 29, 2006, a mud volcano in the Brantas Delta of the Sidoarjo district has emitted mud that has inundated nearby villages. Pollution in this area has been implicated in detrimental effects on fish health. In fishes, leukocyte and phagocytic cells play a vital role in body defenses. We report for the first time the effect of "LUSI" volcano mud on the immune systems of fish in the Brantas Delta. The aim of this study was to find biomarkers to allow the evaluation of the effects of volcanic mud and anthropogenic pollution on fish health in the Brantas Delta. The study took places at the Brantas Delta, which was polluted by volcano mud, and at reference sites in Karangkates and Pasuruan. Leukocyte numbers were determined using a Neubauer hemocytometer and a light microscope. Differential leukocyte counts were determined using blood smears stained with May Grunwald-Giemsa, providing neutrophil, lymphocyte and monocyte counts. Macrophages were taken from fish kidney, and their phagocytic activity was measured. In vitro analyses revealed that leukocyte and differential leukocyte counts (DLC) were higher in Channa striata and Chanos chanos caught from the polluted area. Macrophage numbers were higher in Oreochromis mossambicus than in the other species, indicating that this species is more sensitive to pollution. In areas close to volcanic mud eruption, all specimens had lower phagocytic activity. Our results show that immune cells were changed and phagocytic activity was reduced in the polluted area indicating cytotoxicity and alteration of the innate immune system in fishes exposed to LUSI volcano mud and anthropogenic pollution. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. Leishmania mexicana amazonensis: heterogeneity in 5-nucleotidase and peroxidase activities of mononuclear phagocytes during in vivo and in vitro infection

    OpenAIRE

    Côrte-Real, Suzana; Grimaldi Junior, Gabriel; Meirelles, Maria de Nazareth Leal de

    1988-01-01

    The degree of maturation of cells of the Mononuclear Phagocyte System (MPS), during in vivo and in vitro infection by Leishmania mexicana amazonenesis, was evaluated in this study. The macrophages' differentiation was assayed by cytochemical characterization at the ultrastrctural level, using two well-established markers: 5'-nucleotidase enzyme activity, for revealing the mature cells, and the peroxidase activity present in the cell granules to demonstrate immature mononuclear phagocytes. onl...

  19. [Effect of general magnetotherapy on specific activity of blood phagocytes in patients with ischemic heart disease].

    Science.gov (United States)

    Ishutin, I S; Klemenkov, S V; Lesovskaia, M I; Spiridonova, M S; Krotova, T K; Ishutin, E I; Tsyganova, O B

    2007-01-01

    In general magnetotherapy for patients with hyporeactive phagocytes (less than 67% from the level of normal chelicoluminescent response) the adequate level of magnetic induction is 1 mT, for patients with normoreactive phagocytes--0.5 mT and for patients with hyperreactive phagocytes (more than 133% from the level of normal chelicoluminescent response)--0.75 mT daily.

  20. Chemical composition and phagocyte immunomodulatory activity of Ferula iliensis essential oils.

    Science.gov (United States)

    Özek, Gulmira; Schepetkin, Igor A; Utegenova, Gulzhakhan A; Kirpotina, Liliya N; Andrei, Spencer R; Özek, Temel; Başer, Kemal Hüsnü Can; Abidkulova, Karime T; Kushnarenko, Svetlana V; Khlebnikov, Andrei I; Damron, Derek S; Quinn, Mark T

    2017-06-01

    Essential oil extracts from Ferula iliensis have been used traditionally in Kazakhstan for treatment of inflammation and other illnesses. Because little is known about the biologic activity of these essential oils that contributes to their therapeutic properties, we analyzed their chemical composition and evaluated their phagocyte immunomodulatory activity. The main components of the extracted essential oils were ( E )-propenyl sec -butyl disulfide (15.7-39.4%) and ( Z )-propenyl sec -butyl disulfide (23.4-45.0%). Ferula essential oils stimulated [Ca 2+ ] i mobilization in human neutrophils and activated ROS production in human neutrophils and murine bone marrow phagocytes. Activation of human neutrophil [Ca 2+ ] i flux by Ferula essential oils was dose-dependently inhibited by capsazepine, a TRPV1 channel antagonist, indicating that TRPV1 channels mediate this response. Furthermore, Ferula essential oils stimulated Ca 2+ influx in TRPV1 channel-transfected HEK293 cells and desensitized the capsaicin-induced response in these cells. Additional molecular modeling with known TRPV1 channel agonists suggested that the active component is likely to be ( Z )-propenyl sec -butyl disulfide. Our results provide a cellular and molecular basis to explain at least part of the beneficial therapeutic properties of FEOs. © Society for Leukocyte Biology.

  1. Quantitation of microbicidal activity of mononuclear phagocytes: an in vitro technique.

    Directory of Open Access Journals (Sweden)

    Rege N

    1993-01-01

    Full Text Available An in vitro assay technique was set up to determine the phagocytic and microbicidal activity of a monocyte-macrophage cell line using Candida species as test organisms. The norms were determined for the activity of peritoneal macrophages of rats (24.69 +/- 2.6% phagocytosis and 35.4 +/- 5.22% ICK and human (27.89 +/- 3.63% phagocytosis and 50.91 +/- 6.3% ICK. The assay technique was used to test the degree of activation of macrophages induced by metronidazole, Tinospora cordifolia and Asparaqus racemousus and to compare their effects with a standard immunomodulator muramyl-dipeptide. All the three test agents increased the phagocytic and killing capacity of macrophages in a dose dependent manner upto a certain dose, beyond which either these activities were found to have plateaued or decreased. The optimal doses for MDP, Metronidazole, Asparagus racemosus and Tinospora cordifolia were found to be 100 micrograms, 300 mg/kg, 200 mg/kg and 100 mg/kg respectively. Patients with cirrhosis were screened for defects in monocyte function. The depressed monocyte function (20.58 +/- 5% phago and 41.24 +/- 12.19% ICK; P < 0.05 was observed indicating a compromised host defense. The utility of this candidicidal assay in experimental and clinical studies is discussed.

  2. The modulatory role of cytokines IL-4 and IL-17 in the functional activity of phagocytes in diabetic pregnant women.

    Science.gov (United States)

    Fagundes, Danny L G; França, Eduardo L; Gonzatti, Michelangelo B; Rugde, Marilza V C; Calderon, Iracema M P; Honorio-França, Adenilda C

    2018-01-01

    The study investigated the role of cytokines IL-4 and IL-17 in the modulation of the functional activity of mononuclear phagocytes in diabetic pregnant women with hyperglycemia. Sixty pregnant women were assigned to the following groups: nondiabetic (ND), mild gestational hyperglycemia (MGH), gestational diabetes mellitus (GDM), or type 2 diabetes mellitus (DM2). The functional activity of phagocytes from maternal blood, cord blood, and colostrum was assessed by determining their superoxide release, phagocytosis, microbicidal activity, and intracellular Ca 2+ release. Irrespective of glycemic status, colostrum and blood cells treated with IL-4 and IL-17 increased superoxide release in the presence of enteropathogenic Escherichia coli (EPEC). The highest phagocytosis rate was observed in cells from the DM2 group treated with IL-4. In all the groups, phagocytes from colostrum, maternal blood, and cord blood exhibited higher microbicidal activity against EPEC when treated with cytokines. IL-17 increased intracellular Ca 2+ release by colostrum phagocytes in diabetic groups. The results indicate that the IL-4 and IL-17 modulate the functional activity of phagocytes in the maternal blood, cord blood, and colostrum of diabetic mother. The natural immunity resulting from the interaction between the cells and cytokines tested may be an alternative procedure to improve the prognosis of maternal and newborn infections. © 2017 APMIS. Published by John Wiley & Sons Ltd.

  3. Microglia in Glia-Neuron Co-cultures Exhibit Robust Phagocytic Activity Without Concomitant Inflammation or Cytotoxicity.

    Science.gov (United States)

    Adams, Alexandra C; Kyle, Michele; Beaman-Hall, Carol M; Monaco, Edward A; Cullen, Matthew; Vallano, Mary Lou

    2015-10-01

    A simple method to co-culture granule neurons and glia from a single brain region is described, and microglia activation profiles are assessed in response to naturally occurring neuronal apoptosis, excitotoxin-induced neuronal death, and lipopolysaccharide (LPS) addition. Using neonatal rat cerebellar cortex as a tissue source, glial proliferation is regulated by omission or addition of the mitotic inhibitor cytosine arabinoside (AraC). After 7-8 days in vitro, microglia in AraC(-) cultures are abundant and activated based on their amoeboid morphology, expressions of ED1 and Iba1, and ability to phagocytose polystyrene beads and the majority of neurons undergoing spontaneous apoptosis. Microglia and phagocytic activities are sparse in AraC(+) cultures. Following exposure to excitotoxic kainate concentrations, microglia in AraC(-) cultures phagocytose most dead neurons within 24 h without exacerbating neuronal loss or mounting a strong or sustained inflammatory response. LPS addition induces a robust inflammatory response, based on microglial expressions of TNF-α, COX-2 and iNOS proteins, and mRNAs, whereas these markers are essentially undetectable in control cultures. Thus, the functional effector state of microglia is primed for phagocytosis but not inflammation or cytotoxicity even after kainate exposure that triggers death in the majority of neurons. This model should prove useful in studying the progressive activation states of microglia and factors that promote their conversion to inflammatory and cytotoxic phenotypes.

  4. Defective natural killer and phagocytic activities in chronic obstructive pulmonary disease are restored by glycophosphopeptical (inmunoferón).

    Science.gov (United States)

    Prieto, A; Reyes, E; Bernstein, E D; Martinez, B; Monserrat, J; Izquierdo, J L; Callol, L; de LUCAS, P; Alvarez-Sala, R; Alvarez-Sala, J L; Villarrubia, V G; Alvarez-Mon, M

    2001-06-01

    We have investigated both modifications in natural (innate) immunity caused by chronic obstructive pulmonary disease (COPD) and the effects of a glycophosphopeptical immunomodulator (Inmunoferón) treatment on COPD-associated immunoalterations. In a double-blinded clinical trial, 60 patients with COPD received glycophosphopeptical or placebo during 90 consecutive days at oral doses of 3 g/d. Fifty-six sex- and age-matched healthy control subjects were included as a reference group for immunologic parameters. Peripheral blood natural killer (PBNK) cell cytotoxic activity and phagocytic activity of peripheral monocytes/macrophages (Mo/Ma) and polymorphonuclear (PMN) cells were assessed at baseline and then again at the end of treatments. We found both PBNK activity and phagocytic activity to be significantly decreased in patients with COPD compared with levels in healthy volunteers. The treatment with glycophosphopeptical provoked significant stimulatory effects on PBNK cytotoxic activity. This stimulation was not mediated by an increase in CD3(-)CD56(+) NK cells. Further, glycophosphopeptical significantly increased the percentage of monocytes and PMNs that phagocytize Escherichia coli in vitro, as well as increased phagocytic indices. We conclude that peripheral blood cells of patients with COPD show clear defects in natural immunity that are partially rescued by glycophosphopeptical.

  5. Assessment of inflammatory bowel disease activity by technetium 99m phagocyte scanning

    International Nuclear Information System (INIS)

    Pullman, W.E.; Sullivan, P.J.; Barratt, P.J.; Lising, J.; Booth, J.A.; Doe, W.F.

    1988-01-01

    Autologous technetium 99m-labeled phagocyte scanning has been used to assess disease activity in inflammatory bowel disease in 51 consecutive patients. Strong correlations were found between the 24-h fecal excretion of isotope and the histologic score of mucosal biopsy specimens (rS = 0.84, p less than 0.001, where rS is Spearman's rank correlation coefficient), and between the 24-h fecal excretion of isotope and a clinical inflammatory bowel disease activity index based on the Crohn's disease activity index (rS = 0.87, p less than 0.001). To develop a clinically useful and objective measure of inflammatory bowel disease activity that did not require a 24-h stool collection, the intensity of bowel uptake on scanning was graded visually from 0 to 4, a ratio of count rates for the region of interest to the iliac crest reference region was calculated, and the rapidity of labeled phagocyte uptake into inflamed bowel was measured as the peak uptake time. Visual grading of disease activity on the scans was validated by comparing it with the ratio of count rates from inflamed bowel regions of interest and those from the iliac crest reference region. The ratio of count rates showed a significant correlation with the clinical disease activity index (r = 0.75, p less than 0.001). The visual scan grade also correlated well with the clinical activity index (r = 0.87, p less than 0.001). Count rates from hourly scans were also used to calculate the time of peak uptake of counts for a given region of interest. There was a strong negative correlation between this peak uptake time and the fecal excretion of isotope (rS = -0.81, p less than 0.001), a clinical activity index (r = -0.60, p less than 0.001), and the histologic score of the mucosal biopsy specimens (r = -0.84, p less than 0.001)

  6. Degalactosylated/Desialylated Bovine Colostrum Induces Macrophage Phagocytic Activity Independently of Inflammatory Cytokine Production.

    Science.gov (United States)

    Uto, Yoshihiro; Kawai, Tomohito; Sasaki, Toshihide; Hamada, Ken; Yamada, Hisatsugu; Kuchiike, Daisuke; Kubo, Kentaro; Inui, Toshio; Mette, Martin; Tokunaga, Ken; Hayakawa, Akio; Go, Akiteru; Oosaki, Tomohiro

    2015-08-01

    Colostrum contains antibodies, such as immunoglobulin G (IgG), immunoglobulin A (IgA) and immunoglobulin M (IgM), and, therefore, has potent immunomodulating activity. In particular, IgA has an O-linked sugar chain similar to that in the group-specific component (Gc) protein, a precursor of the Gc protein-derived macrophage-activating factor (GcMAF). In the present study, we investigated the macrophage-activating effects of degalactosylated/desialylated bovine colostrum. We detected the positive band in degalactosylated/ desialylated bovine colostrum by western blotting using Helix pomatia agglutinin lectin. We also found that degalactosylated/ desialylated bovine colostrum could significantly enhance the phagocytic activity of mouse peritoneal macrophages in vitro and of intestinal macrophages in vivo. Besides, degalactosylated/desialylated bovine colostrum did not mediate the production of inflammatory cytokines such as tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β). Similar to the use of GcMAF, degalactosylated/desialylated bovine colostrum can be used as a potential macrophage activator for various immunotherapies. Copyright© 2015 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

  7. Effect of influenza infection on the phagocytic and bactericidal activities of pulmonary macrophages

    International Nuclear Information System (INIS)

    Nugent, K.M.; Pesanti, E.L.

    1979-01-01

    The effect of mouse-adapted influenza A/PR/8/34 virus on pulmonary macrophage function was evaluated by using an in vitro system which allowed direct virus interaction with macrophages and then separate analysis of the steps required for bacterial clearance by macrophages. Infection of macrophages with this virus resulted in the appearance of a hemagglutinating activity on the macrophage surface; expression of this activity was inhibited by amantadine, 2-deoxyglucose, and cycloheximide and by pretreatment of the virus inoculum with with ultraviolet light and specific antiserum. After influenza infection, net ingestion of viable Staphylococcus aureus by macrophage monolayers was unaltered and there was no change in the fraction of the monolayer which ingested cocci over a wide range of bacterial inputs. Influenza-infected microphages also inactivated intracellular S. aureus at a rate indistinguishable from controls. Therefore, these in vitro studies do not support the hypothesis that the defect in pulmonary antibacterial mechanisms associated with influenza infections results from a direct effect of virus infection on either the phagocytic or bactericidal activity of resistant pulmonary macarophages

  8. Degalactosylated/desialylated human serum containing GcMAF induces macrophage phagocytic activity and in vivo antitumor activity.

    Science.gov (United States)

    Kuchiike, Daisuke; Uto, Yoshihiro; Mukai, Hirotaka; Ishiyama, Noriko; Abe, Chiaki; Tanaka, Daichi; Kawai, Tomohito; Kubo, Kentaro; Mette, Martin; Inui, Toshio; Endo, Yoshio; Hori, Hitoshi

    2013-07-01

    The group-specific component protein-derived macrophage-activating factor (GcMAF) has various biological activities, such as macrophage activation and antitumor activity. Clinical trials of GcMAF have been carried out for metastatic breast cancer, prostate cancer, and metastatic colorectal cancer. In this study, despite the complicated purification process of GcMAF, we used enzymatically-treated human serum containing GcMAF with a considerable macrophage-stimulating activity and antitumor activity. We detected GcMAF in degalactosylated/desialylated human serum by western blotting using an anti-human Gc globulin antibody, and Helix pomatia agglutinin lectin. We also found that GcMAF-containing human serum significantly enhanced the phagocytic activity of mouse peritoneal macrophages and extended the survival time of mice bearing Ehrlich ascites tumors. We demonstrated that GcMAF-containing human serum can be used as a potential macrophage activator for cancer immunotherapy.

  9. Chloride flux in phagocytes.

    Science.gov (United States)

    Wang, Guoshun

    2016-09-01

    Phagocytes, such as neutrophils and macrophages, engulf microbes into phagosomes and launch chemical attacks to kill and degrade them. Such a critical innate immune function necessitates ion participation. Chloride, the most abundant anion in the human body, is an indispensable constituent of the myeloperoxidase (MPO)-H2 O2 -halide system that produces the potent microbicide hypochlorous acid (HOCl). It also serves as a balancing ion to set membrane potentials, optimize cytosolic and phagosomal pH, and regulate phagosomal enzymatic activities. Deficient supply of this anion to or defective attainment of this anion by phagocytes is linked to innate immune defects. However, how phagocytes acquire chloride from their residing environment especially when they are deployed to epithelium-lined lumens, and how chloride is intracellularly transported to phagosomes remain largely unknown. This review article will provide an overview of chloride protein carriers, potential mechanisms for phagocytic chloride preservation and acquisition, intracellular chloride supply to phagosomes for oxidant production, and methods to measure chloride levels in phagocytes and their phagosomes. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  10. Phagocytic activities of hemocytes from the deep-sea symbiotic mussels Bathymodiolus japonicus, B. platifrons, and B. septemdierum.

    Science.gov (United States)

    Tame, Akihiro; Yoshida, Takao; Ohishi, Kazue; Maruyama, Tadashi

    2015-07-01

    Deep-sea mytilid mussels harbor symbiotic bacteria in their gill epithelial cells that are horizontally or environmentally transmitted to the next generation of hosts. To understand the immune defense system in deep-sea symbiotic mussels, we examined the hemocyte populations of the symbiotic Bathymodiolus mussel species Bathymodiolus japonicus, Bathymodiolus platifrons, and Bathymodiolus septemdierum, and characterized three types of hemocytes: agranulocytes (AGs), basophilic granulocytes (BGs), and eosinophilic granulocytes (EGs). Of these, the EG cells were the largest (diameter, 8.4-10.0 μm) and had eosinophilic cytoplasm with numerous eosinophilic granules (diameter, 0.8-1.2 μm). Meanwhile, the BGs were of medium size (diameter, 6.7-8.0 μm) and contained small basophilic granules (diameter, 0.3-0.4 μm) in basophilic cytoplasm, and the AGs, the smallest of the hemocytes (diameter, 4.8-6.0 μm), had basophilic cytoplasm lacking granules. A lectin binding assay revealed that concanavalin A bound to all three hemocyte types, while wheat germ agglutinin bound exclusively to EGs and BGs. The total hemocyte population densities within the hemolymph of all three Bathymodiolus mussel species were similar (8.4-13.3 × 10(5) cells/mL), and the percentages of circulating AGs, BGs, and EGs in the hemolymph of these organisms were 44.7-48.5%, 14.3-17.6%, and 34.3-41.0%, respectively. To analyze the functional differences between these hemocytes, the phagocytic activity and post-phagocytic phagosome-lysosome fusion events were analyzed in each cell type using a fluorescent Alexa Fluor(®) 488-conjugated Escherichia coli bioparticle and a LysoTracker(®) lysosomal marker, respectively. While the AGs exhibited no phagocytic activity, both types of granulocytes were phagocytic. Of the three hemocyte types, the EGs exhibited the highest level of phagocytic activity as well as rapid phagosome-lysosome fusion, which occurred within 2 h of incubation. Meanwhile, the BGs showed

  11. Serratia marcescens Is Able to Survive and Proliferate in Autophagic-Like Vacuoles inside Non-Phagocytic Cells

    Science.gov (United States)

    Colombo, María Isabel; García Véscovi, Eleonora

    2011-01-01

    Serratia marcescens is an opportunistic human pathogen that represents a growing problem for public health, particularly in hospitalized or immunocompromised patients. However, little is known about factors and mechanisms that contribute to S. marcescens pathogenesis within its host. In this work, we explore the invasion process of this opportunistic pathogen to epithelial cells. We demonstrate that once internalized, Serratia is able not only to persist but also to multiply inside a large membrane-bound compartment. This structure displays autophagic-like features, acquiring LC3 and Rab7, markers described to be recruited throughout the progression of antibacterial autophagy. The majority of the autophagic-like vacuoles in which Serratia resides and proliferates are non-acidic and have no degradative properties, indicating that the bacteria are capable to either delay or prevent fusion with lysosomal compartments, altering the expected progression of autophagosome maturation. In addition, our results demonstrate that Serratia triggers a non-canonical autophagic process before internalization. These findings reveal that S. marcescens is able to manipulate the autophagic traffic, generating a suitable niche for survival and proliferation inside the host cell. PMID:21901159

  12. Influence of indicators for thiotriazolin phagocytic activity of leukocytes in the blood in the later period of development of stomach ulcers against pneumonia

    Directory of Open Access Journals (Sweden)

    L. O. Furdychko

    2017-07-01

    Full Text Available Important for the pathogenesis of pneumonia and gastric ulcers should state phagocytic activity of leukocytes (PHAL in the blood. In fact the state of nonspecific resistance factors to some extent depends on the disease, the development of complications, prognosis and therapy. Materials and methods. The study was conducted on 49 male guinea pigs. The experimental pneumonia caused by the method Shlyapnykova V. N., Solodova T. L., gastric ulcer simulated method Komarov V. I. Nonspecific resistance of animals we evaluated, examining the phagocytic activity of leukocytes (PHAL, nitroblue tetrazolium test (NST- test. Phagocytic activity of leukocytes (PHAL in blood were studied in terms phagocytic index (PHI and the phagocytic number (PHN and determined by the method Menshikov V. V. NST - test method Vyksmana M. E., Mayanskoho A. H. The figures research results processed by statistical method Student. Results and discussion. For the experiment, we selected two models of disease: experimental pneumonia (EP and peptic ulcer (PU. State PHAL determined by the level of phagocytic number (PHN, phagocytic index (PHI, NST-test levels in the ЕP+ PU. Found that in the 10-th and 18-th day of development of pathological process both in the stomach and the lungs of guinea pigs, there was reduction of PHI respectively 15,8% (P

  13. Melatonin signaling affects the timing in the daily rhythm of phagocytic activity by the retinal pigment epithelium.

    Science.gov (United States)

    Laurent, Virgine; Sengupta, Anamika; Sánchez-Bretaño, Aída; Hicks, David; Tosini, Gianluca

    2017-12-01

    Earlier studies in Xenopus have indicated a role for melatonin in the regulation of retinal disk shedding, but the role of melatonin in the regulation of daily rhythm in mammalian disk shedding and phagocytosis is still unclear. We recently produced a series of transgenic mice lacking melatonin receptor type 1 (MT 1 ) or type 2 (MT 2 ) in a melatonin-proficient background and have shown that removal of MT 1 and MT 2 receptors induces significant effects on daily and circadian regulation of the electroretinogram as well as on the viability of photoreceptor cells during aging. In this study we investigated the daily rhythm of phagocytic activity by the retinal pigment epithelium in MT 1 and MT 2 knock-out mice. Our data indicate that in MT 1 and MT 2 knock-out mice the peak of phagocytosis is advanced by 3 h with respect to wild-type mice and occurred in dark rather than after the onset of light, albeit the mean phagocytic activity over the 24-h period did not change among the three genotypes. Nevertheless, this small change in the profile of daily phagocytic rhythms may produce a significant effect on retinal health since MT 1 and MT 2 knock-out mice showed a significant increase in lipofuscin accumulation in the retinal pigment epithelium. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. One-year follow-up of the phagocytic activity of leukocytes after exposure of rats to asbestos and basalt fibers.

    Science.gov (United States)

    Hurbánková, M

    1994-01-01

    The phagocytic activity of leukocytes in peripheral blood was investigated after 2, 24, and 48 hr; 1, 2, 4, and 8 weeks; and 6 and 12 months following intraperitoneal administration of asbestos and basalt fibers to Wistar rats. Asbestos and basalt fibers differed in their effects on the parameters studied. Both granulocyte count and phagocytic activity of leukocytes during the 1-year dynamic follow-up in both dust-exposed groups of animals changed in two phases, characterized by the initial stimulation of the acute phase I, followed by the suppression of the parameters in the chronic phase II. Exposure to asbestos and basalt fibers led, in phase II, to impairment of the phagocytic activity of granulocytes. Asbestos fibers also significantly decreased phagocytic activity of monocytes. Exposure to basalt fibers did not affect the phagocytic activity of monocytes in phase II. Results suggest that the monocytic component of leukocytes plays an important role in the development of diseases caused by exposure to fibrous dusts, but basalt fibers have lesser biological effects than asbestos fibers. PMID:7882931

  15. Effect of the Gc-derived macrophage-activating factor precursor (preGcMAF) on phagocytic activation of mouse peritoneal macrophages.

    Science.gov (United States)

    Uto, Yoshihiro; Yamamoto, Syota; Takeuchi, Ryota; Nakagawa, Yoshinori; Hirota, Keiji; Terada, Hiroshi; Onizuka, Shinya; Nakata, Eiji; Hori, Hitoshi

    2011-07-01

    The 1f1f subtype of the Gc protein (Gc(1f1f) protein) was converted into Gc-derived macrophage-activating factor (GcMAF) by enzymatic processing in the presence of β-galactosidase of an activated B-cell and sialidase of a T-cell. We hypothesized that preGc(1f1f)MAF, the only Gc(1f1f) protein lacking galactose, can be converted to GcMAF in vivo because sialic acid is cleaved by residual sialidase. Hence, we investigated the effect of preGc(1f1f)MAF on the phagocytic activation of mouse peritoneal macrophages. We examined the sugar moiety of preGc(1f1f)MAF with a Western blot using peanut agglutinin (PNA) and Helix pomatia agglutinin (HPA) lectin. We also found that preGc(1f1f)MAF significantly enhanced phagocytic activity in mouse peritoneal macrophages but only in the presence of the mouse peritoneal fluid; the level of phagocytic activity was the same as that observed for GcMAF. PreGc(1f1f)MAF can be used as an effective macrophage activator in vivo.

  16. In vitro studies on the relationship between the anti-inflammatory activity of Physalis peruviana extracts and the phagocytic process.

    Science.gov (United States)

    Martínez, Willington; Ospina, Luis Fernando; Granados, Diana; Delgado, Gabriela

    2010-03-01

    The study of plants used in traditional medicine has drawn the attention of researchers as an alternative in the development of new therapeutics agents, such as the American Solanaceae Physalis peruviana, which has significant anti-inflammatory activity. The Physalis peruviana anti-inflammatory effect of ethanol or ether calyces extracts on the phagocytic process was assessed by using an in vitro phagocytosis model (Leishmania panamensis infection to murine macrophages). The Physalis peruviana extracts do not inhibit microorganism internalization and have no parasiticide effect. Most ET and EP extracts negatively affected the parasite's invasion of macrophages (Infected cells increased.). This observation might result from a down-regulation of the macrophage's microbicide ability associated with a selective reduction of proinflammatory cytokines levels. Physalis peruviana's anti-inflammatory activity described in this model is related to an immunomodulatory effect exerted on macrophages infected, which directly or indirectly "blocks" their ability to secrete soluble proinflammatory mediators.

  17. Inhibitory Effects of Standardized Extracts of Phyllanthus amarus and Phyllanthus urinaria and Their Marker Compounds on Phagocytic Activity of Human Neutrophils

    Directory of Open Access Journals (Sweden)

    Yuandani

    2013-01-01

    Full Text Available The standardized methanol extracts of Phyllanthus amarus and P. urinaria, collected from Malaysia and Indonesia, and their isolated chemical markers, phyllanthin and hypophyllanthin, were evaluated for their effects on the chemotaxis, phagocytosis and chemiluminescence of human phagocytes. All the plant extracts strongly inhibited the migration of polymorphonuclear leukocytes (PMNs with the Malaysian P. amarus showing the strongest inhibitory activity (IC50 value, 1.1 µg/mL. There was moderate inhibition by the extracts of the bacteria engulfment by the phagocytes with the Malaysian P. amarus exhibiting the highest inhibition (50.8% of phagocytizing cells. The Malaysian P. amarus and P. urinaria showed strong reactive oxygen species (ROS inhibitory activity, with both extracts exhibiting IC50 value of 0.7 µg/mL. Phyllanthin and hypophyllanthin exhibited relatively strong activity against PMNs chemotaxis, with IC50 values slightly lower than that of ibuprofen (1.4 µg/mL. Phyllanthin exhibited strong inhibitory activity on the oxidative burst with an IC50 value comparable to that of aspirin (1.9 µg/mL. Phyllanthin exhibited strong engulfment inhibitory activity with percentage of phagocytizing cells of 14.2 and 27.1% for neutrophils and monocytes, respectively. The strong inhibitory activity of the extracts was due to the presence of high amounts of phyllanthin and hypophyllanthin although other constituents may also contribute.

  18. Heterophil Phagocytic Activity Stimulated by L61 and L55 Supplementation in Broilers with Infection

    Directory of Open Access Journals (Sweden)

    Pairat Sornplang

    2015-11-01

    Full Text Available Newborn chicks are susceptible to Salmonella enterica serovar Enteritidis (SE. The objective of this study was to evaluate the effect of Lactobacillus probiotic isolated from chicken feces on heterophil phagocytosis in broiler chicks. A total of 150 newborn broiler chicks were divided into 5 groups (30 chicks per group as follows: group 1 (normal control, given feed and water only, group 2 (positive control given feed, water and SE infection, group 3 (L61 treated given feed, water, SE infection followed by Lactobacillus salivarius L61 treatment, group 4 (L55 treated given feed, water, SE infection followed by L. salivarius L55 treatment, and group 5 given feed, water, SE infection followed by L. salivarius L61 + L55 combination treatment. After SE infection, L. salivarius treatment lasted for 7 days. The results showed that L. salivarius L61 and L. salivarius L55 treatment, either alone or combination of both, increased the survival rate after SE infection, and upregulated heterophil phagocytosis and phagocytic index (PI. Conversely, chick groups treated with Lactobacillus showed lower SE recovery rate from cecal tonsils than that of the positive control group. The PI values of the chicken group with SE infection, followed by the combination of L. salivarius L61 and L. salivarius L55 were the highest as compared to either positive control or normal control group. Two Lactobacillus strains supplementation group showed significantly (p<0.05 higher PI value at 48 h than 24 h after treatment.

  19. Lipofuscin-mediated photic stress inhibits phagocytic activity of ARPE-19 cells; effect of donors' age and antioxidants.

    Science.gov (United States)

    Olchawa, Magdalena M; Furso, Justyna A; Szewczyk, Grzegorz M; Sarna, Tadeusz J

    2017-10-01

    The risk of chronic oxidative stress in the retinal pigment epithelium (RPE) increases with age due to accumulation of the photoreactive age pigment lipofuscin (LFG). Here, we asked whether sublethal and weakly lethal photic stress, induced by irradiation of ARPE-19 cells containing phagocytised LFG, affected the cell specific phagocytic activity, which is critically important for proper functioning and survival of the retina, and if natural antioxidants could modify the observed outcomes. ARPE-19 cells preloaded with LFG isolated from human donors of different age or containing LFG enriched with zeaxanthin and α-tocopherol (LFG-A), were irradiated with blue light. Phagocytosis of fluorescein-5-isothiocyanate (FITC)-labelled photoreceptor outer segments was determined by flow cytometry. Photoreactivity of LFG and LFG-A was analysed by measuring photoconsumption of oxygen and photogeneration of singlet oxygen mediated by the granules. LFG-mediated photic stress in ARPE-19 cells induced significant inhibition of their specific phagocytosis. The inhibitory effect increased with age of LFG donors and was reduced by enrichment of the granules with antioxidants. Oxygen consumption and generation of singlet oxygen induced by the photoexcited LFG increased with donor's age and was partially quenched by antioxidants. Although the phototoxic potential of lipofuscin increased with age, natural antioxidants reduced photoreactivity of LFG and their efficiency to induce oxidative stress. This study has demonstrated, for the first time, that mild oxidative stress, mediated by the age pigment lipofuscin, impairs specific phagocytic activity of RPE, and that natural antioxidants can protect this important cellular function by reducing lipofuscin photoreactivity.

  20. The effect of core and lanthanide ion dopants in sodium fluoride-based nanocrystals on phagocytic activity of human blood leukocytes

    International Nuclear Information System (INIS)

    Sojka, Bartlomiej; Liskova, Aurelia; Kuricova, Miroslava; Banski, Mateusz; Misiewicz, Jan; Dusinska, Maria; Horvathova, Mira; Ilavska, Silvia; Szabova, Michaela; Rollerova, Eva; Podhorodecki, Artur; Tulinska, Jana

    2017-01-01

    Sodium fluoride-based β-NaLnF4 nanoparticles (NPs) doped with lanthanide ions are promising materials for application as luminescent markers in bio-imaging. In this work, the effect of NPs doped with yttrium (Y), gadolinium (Gd), europium (Eu), thulium (Tm), ytterbium (Yb) and terbium (Tb) ions on phagocytic activity of monocytes and granulocytes and the respiratory burst was examined. The surface functionalization of <10-nm NPs was performed according to our variation of patent pending ligand exchange method that resulted in meso-2,3-dimercaptosuccinic acid (DMSA) molecules on their surface. Y-core-based NCs were doped with Eu ions, which enabled them to be excited with UV light wavelengths. Cultures of human peripheral blood (n = 8) were in vitro treated with five different concentrations of eight NPs for 24 h. In summary, neither type of nanoparticles is found toxic with respect to conducted test; however, some cause toxic effects (they have statistically significant deviations compared to reference) in some selected doses tested. Both core types of NPs (Y-core and Gd-core) impaired the phagocytic activity of monocytes the strongest, having minimal or none whatsoever influence on granulocytes and respiratory burst of phagocytic cells. The lowest toxicity was observed in Gd-core, Yb, Tm dopants and near-infrared nanoparticles. Clear dose-dependent effect of NPs on phagocytic activity of leukocytes and respiratory burst of cells was observed for limited number of samples.

  1. The effect of core and lanthanide ion dopants in sodium fluoride-based nanocrystals on phagocytic activity of human blood leukocytes

    Science.gov (United States)

    Sojka, Bartlomiej; Liskova, Aurelia; Kuricova, Miroslava; Banski, Mateusz; Misiewicz, Jan; Dusinska, Maria; Horvathova, Mira; Ilavska, Silvia; Szabova, Michaela; Rollerova, Eva; Podhorodecki, Artur; Tulinska, Jana

    2017-02-01

    Sodium fluoride-based β-NaLnF4 nanoparticles (NPs) doped with lanthanide ions are promising materials for application as luminescent markers in bio-imaging. In this work, the effect of NPs doped with yttrium (Y), gadolinium (Gd), europium (Eu), thulium (Tm), ytterbium (Yb) and terbium (Tb) ions on phagocytic activity of monocytes and granulocytes and the respiratory burst was examined. The surface functionalization of toxic with respect to conducted test; however, some cause toxic effects (they have statistically significant deviations compared to reference) in some selected doses tested. Both core types of NPs (Y-core and Gd-core) impaired the phagocytic activity of monocytes the strongest, having minimal or none whatsoever influence on granulocytes and respiratory burst of phagocytic cells. The lowest toxicity was observed in Gd-core, Yb, Tm dopants and near-infrared nanoparticles. Clear dose-dependent effect of NPs on phagocytic activity of leukocytes and respiratory burst of cells was observed for limited number of samples.

  2. Molecular cloning of rock bream (Oplegnathus fasciatus) tumor necrosis factor-alpha and its effect on the respiratory burst activity of phagocytes.

    Science.gov (United States)

    Kim, Min Sun; Hwang, Yoon Jung; Yoon, Ki Joon; Zenke, Kosuke; Nam, Yoon Kwon; Kim, Sung Koo; Kim, Ki Hong

    2009-11-01

    Rock bream (Oplegnathus fasciatus) tumor necrosis factor-alpha (rbTNF-alpha) gene was cloned, recombinantly produced, and the effect of the recombinant rbTNF-alpha on the respiratory burst activity of rock bream phagocytes was analyzed. Structurally, genomic DNA of rbTNF-alpha was comprised with four exons and three introns, and deduced amino acid sequence of its cDNA possessed the TNF family signature, a transmembrane domain, a protease cleavage site, and two cysteine residues, which are the typical characteristics of TNF-alpha gene in mammals and fish. The chemiluminescent (CL) response of rock bream phagocytes was significantly enhanced by pre-incubation with recombinant rbTNF-alpha, when opsonized zymosan was used as a stimulant of the respiratory burst. However, CL enhancing effect of the recombinant rbTNF-alpha was very weak when the respiratory burst activity of phagocytes was triggered with phorbol-12-myristate-13-acetate (PMA) instead of zymosan. These results suggest that rock bream TNF-alpha might have an ability to prime the respiratory burst activity of phagocytes against receptor-mediated phagocytosis inducing stimulants, such as zymosan, but have little ability against stimulants not accompanying receptor-mediated phagocytosis.

  3. The effect of core and lanthanide ion dopants in sodium fluoride-based nanocrystals on phagocytic activity of human blood leukocytes

    Energy Technology Data Exchange (ETDEWEB)

    Sojka, Bartlomiej [Wroclaw University of Science and Technology, Department of Experimental Physics (Poland); Liskova, Aurelia; Kuricova, Miroslava [Slovak Medical University, Medical Faculty, Department of Immunology and Immunotoxicology (Slovakia); Banski, Mateusz; Misiewicz, Jan [Wroclaw University of Science and Technology, Department of Experimental Physics (Poland); Dusinska, Maria [Norwegian Institute for Air Research, Health Effects Laboratory, Department of Environmental Chemistry (Norway); Horvathova, Mira; Ilavska, Silvia; Szabova, Michaela [Slovak Medical University, Medical Faculty, Department of Immunology and Immunotoxicology (Slovakia); Rollerova, Eva [Slovak Medical University, Faculty of Public Health, Department of Toxicology (Slovakia); Podhorodecki, Artur, E-mail: artur.p.podhorodecki@pwr.edu.pl [Wroclaw University of Science and Technology, Department of Experimental Physics (Poland); Tulinska, Jana, E-mail: jana.tulinska@szu.sk [Slovak Medical University, Medical Faculty, Department of Immunology and Immunotoxicology (Slovakia)

    2017-02-15

    Sodium fluoride-based β-NaLnF4 nanoparticles (NPs) doped with lanthanide ions are promising materials for application as luminescent markers in bio-imaging. In this work, the effect of NPs doped with yttrium (Y), gadolinium (Gd), europium (Eu), thulium (Tm), ytterbium (Yb) and terbium (Tb) ions on phagocytic activity of monocytes and granulocytes and the respiratory burst was examined. The surface functionalization of <10-nm NPs was performed according to our variation of patent pending ligand exchange method that resulted in meso-2,3-dimercaptosuccinic acid (DMSA) molecules on their surface. Y-core-based NCs were doped with Eu ions, which enabled them to be excited with UV light wavelengths. Cultures of human peripheral blood (n = 8) were in vitro treated with five different concentrations of eight NPs for 24 h. In summary, neither type of nanoparticles is found toxic with respect to conducted test; however, some cause toxic effects (they have statistically significant deviations compared to reference) in some selected doses tested. Both core types of NPs (Y-core and Gd-core) impaired the phagocytic activity of monocytes the strongest, having minimal or none whatsoever influence on granulocytes and respiratory burst of phagocytic cells. The lowest toxicity was observed in Gd-core, Yb, Tm dopants and near-infrared nanoparticles. Clear dose-dependent effect of NPs on phagocytic activity of leukocytes and respiratory burst of cells was observed for limited number of samples.

  4. Effect of intravenous plasma transfusion on granulocyte and monocyte oxidative and phagocytic activity in dairy calves with failure of passive immunity.

    Science.gov (United States)

    Yang, Victoria C; Rayburn, Maire C; Chigerwe, Munashe

    2017-12-01

    Plasma administration has been recommended in calves older than 48h with failure of passive immunity (FPI) to provide immunity consistent with adequate colostral ingestion. However, the protective serum immunoglobulin G (IgG) concentrations (≥1000mg/dL) of plasma derived IgG only lasts up to 12h. In addition to IgG, maternally derived colostral cells also confer immunity. The objective of the study was to determine the effect of intravenous plasma transfusion on granulocyte and monocyte oxidative and phagocytic activity in calves with FPI. Twenty-seven, one day-old, Jersey calves were assigned into 3 groups. The colostral (CL, N=9) group received 3L of colostrum once by oroesophageal tubing. Two other groups of calves received 1L of colostrum once by oroesophageal tubing and were assigned based on their health status (sick or non-sick) at 4days of age, as the sick-group (SG, N=7) or the non-sick (NG, N=11) groups. At 4days of age, the SG and NG groups were administered plasma intravenously at 30mL/kg. Granulocyte and monocyte oxidative and phagocytic activity was determined by flow cytometry. There was no significant difference in the granulocyte and monocyte oxidative or phagocytic activity among the 3 groups (P>0.05). Plasma administration had no significant effect on the oxidative or phagocytic activity of granulocytes or monocytes. In clinical practice, plasma administration for enhancing oxidative or phagocytic activity of granulocytes or monocytes, alone, might not be justified in calves with FPI. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Dental Calculus Stimulates Interleukin-1β Secretion by Activating NLRP3 Inflammasome in Human and Mouse Phagocytes.

    Directory of Open Access Journals (Sweden)

    Jorge Luis Montenegro Raudales

    Full Text Available Dental calculus is a mineralized deposit associated with periodontitis. The bacterial components contained in dental calculus can be recognized by host immune sensors, such as Toll-like receptors (TLRs, and induce transcription of proinflammatory cytokines, such as IL-1β. Studies have shown that cellular uptake of crystalline particles may trigger NLRP3 inflammasome activation, leading to the cleavage of the IL-1β precursor to its mature form. Phagocytosis of dental calculus in the periodontal pocket may therefore lead to the secretion of IL-1β, promoting inflammatory responses in periodontal tissues. However, the capacity of dental calculus to induce IL-1β secretion in human phagocytes has not been explored. To study this, we stimulated human polymorphonuclear leukocytes (PMNs and peripheral blood mononuclear cells (PBMCs with dental calculus collected from periodontitis patients, and measured IL-1β secretion by ELISA. We found that calculus induced IL-1β secretion in both human PMNs and PBMCs. Calculus also induced IL-1β in macrophages from wild-type mice, but not in macrophages from NLRP3- and ASC-deficient mice, indicating the involvement of NLRP3 and ASC. IL-1β induction was inhibited by polymyxin B, suggesting that LPS is one of the components of calculus that induces pro-IL-1β transcription. To analyze the effect of the inorganic structure, we baked calculus at 250°C for 1 h. This baked calculus failed to induce pro-IL-1β transcription. However, it did induce IL-1β secretion in lipid A-primed cells, indicating that the crystalline structure of calculus induces inflammasome activation. Furthermore, hydroxyapatite crystals, a component of dental calculus, induced IL-1β in mouse macrophages, and baked calculus induced IL-1β in lipid A-primed human PMNs and PBMCs. These results indicate that dental calculus stimulates IL-1β secretion via NLRP3 inflammasome in human and mouse phagocytes, and that the crystalline structure has a

  6. Dental Calculus Stimulates Interleukin-1β Secretion by Activating NLRP3 Inflammasome in Human and Mouse Phagocytes.

    Science.gov (United States)

    Montenegro Raudales, Jorge Luis; Yoshimura, Atsutoshi; Sm, Ziauddin; Kaneko, Takashi; Ozaki, Yukio; Ukai, Takashi; Miyazaki, Toshihiro; Latz, Eicke; Hara, Yoshitaka

    2016-01-01

    Dental calculus is a mineralized deposit associated with periodontitis. The bacterial components contained in dental calculus can be recognized by host immune sensors, such as Toll-like receptors (TLRs), and induce transcription of proinflammatory cytokines, such as IL-1β. Studies have shown that cellular uptake of crystalline particles may trigger NLRP3 inflammasome activation, leading to the cleavage of the IL-1β precursor to its mature form. Phagocytosis of dental calculus in the periodontal pocket may therefore lead to the secretion of IL-1β, promoting inflammatory responses in periodontal tissues. However, the capacity of dental calculus to induce IL-1β secretion in human phagocytes has not been explored. To study this, we stimulated human polymorphonuclear leukocytes (PMNs) and peripheral blood mononuclear cells (PBMCs) with dental calculus collected from periodontitis patients, and measured IL-1β secretion by ELISA. We found that calculus induced IL-1β secretion in both human PMNs and PBMCs. Calculus also induced IL-1β in macrophages from wild-type mice, but not in macrophages from NLRP3- and ASC-deficient mice, indicating the involvement of NLRP3 and ASC. IL-1β induction was inhibited by polymyxin B, suggesting that LPS is one of the components of calculus that induces pro-IL-1β transcription. To analyze the effect of the inorganic structure, we baked calculus at 250°C for 1 h. This baked calculus failed to induce pro-IL-1β transcription. However, it did induce IL-1β secretion in lipid A-primed cells, indicating that the crystalline structure of calculus induces inflammasome activation. Furthermore, hydroxyapatite crystals, a component of dental calculus, induced IL-1β in mouse macrophages, and baked calculus induced IL-1β in lipid A-primed human PMNs and PBMCs. These results indicate that dental calculus stimulates IL-1β secretion via NLRP3 inflammasome in human and mouse phagocytes, and that the crystalline structure has a partial role in

  7. Dental Calculus Stimulates Interleukin-1β Secretion by Activating NLRP3 Inflammasome in Human and Mouse Phagocytes

    Science.gov (United States)

    Montenegro Raudales, Jorge Luis; Yoshimura, Atsutoshi; SM, Ziauddin; Kaneko, Takashi; Ozaki, Yukio; Ukai, Takashi; Miyazaki, Toshihiro; Latz, Eicke; Hara, Yoshitaka

    2016-01-01

    Dental calculus is a mineralized deposit associated with periodontitis. The bacterial components contained in dental calculus can be recognized by host immune sensors, such as Toll-like receptors (TLRs), and induce transcription of proinflammatory cytokines, such as IL-1β. Studies have shown that cellular uptake of crystalline particles may trigger NLRP3 inflammasome activation, leading to the cleavage of the IL-1β precursor to its mature form. Phagocytosis of dental calculus in the periodontal pocket may therefore lead to the secretion of IL-1β, promoting inflammatory responses in periodontal tissues. However, the capacity of dental calculus to induce IL-1β secretion in human phagocytes has not been explored. To study this, we stimulated human polymorphonuclear leukocytes (PMNs) and peripheral blood mononuclear cells (PBMCs) with dental calculus collected from periodontitis patients, and measured IL-1β secretion by ELISA. We found that calculus induced IL-1β secretion in both human PMNs and PBMCs. Calculus also induced IL-1β in macrophages from wild-type mice, but not in macrophages from NLRP3- and ASC-deficient mice, indicating the involvement of NLRP3 and ASC. IL-1β induction was inhibited by polymyxin B, suggesting that LPS is one of the components of calculus that induces pro-IL-1β transcription. To analyze the effect of the inorganic structure, we baked calculus at 250°C for 1 h. This baked calculus failed to induce pro-IL-1β transcription. However, it did induce IL-1β secretion in lipid A-primed cells, indicating that the crystalline structure of calculus induces inflammasome activation. Furthermore, hydroxyapatite crystals, a component of dental calculus, induced IL-1β in mouse macrophages, and baked calculus induced IL-1β in lipid A-primed human PMNs and PBMCs. These results indicate that dental calculus stimulates IL-1β secretion via NLRP3 inflammasome in human and mouse phagocytes, and that the crystalline structure has a partial role in

  8. Titanium dioxide nanoparticles stimulate sea urchin immune cell phagocytic activity involving TLR/p38 MAPK-mediated signalling pathway

    Science.gov (United States)

    Pinsino, Annalisa; Russo, Roberta; Bonaventura, Rosa; Brunelli, Andrea; Marcomini, Antonio; Matranga, Valeria

    2015-01-01

    Titanium dioxide nanoparticles (TiO2NPs) are one of the most widespread-engineered particles in use for drug delivery, cosmetics, and electronics. However, TiO2NP safety is still an open issue, even for ethical reasons. In this work, we investigated the sea urchin Paracentrotus lividus immune cell model as a proxy to humans, to elucidate a potential pathway that can be involved in the persistent TiO2NP-immune cell interaction in vivo. Morphology, phagocytic ability, changes in activation/inactivation of a few mitogen-activated protein kinases (p38 MAPK, ERK), variations of other key proteins triggering immune response (Toll-like receptor 4-like, Heat shock protein 70, Interleukin-6) and modifications in the expression of related immune response genes were investigated. Our findings indicate that TiO2NPs influence the signal transduction downstream targets of p38 MAPK without eliciting an inflammatory response or other harmful effects on biological functions. We strongly recommend sea urchin immune cells as a new powerful model for nano-safety/nano-toxicity investigations without the ethical normative issue. PMID:26412401

  9. Complement Receptor 3-Mediated Inhibition of Inflammasome Priming by Ras GTPase-Activating Protein During Francisella tularensis Phagocytosis by Human Mononuclear Phagocytes

    Directory of Open Access Journals (Sweden)

    Ky V. Hoang

    2018-03-01

    Full Text Available Francisella tularensis is a remarkably infectious facultative intracellular bacterium of macrophages that causes tularemia. Early evasion of host immune responses contributes to the success of F. tularensis as a pathogen. F. tularensis entry into human monocytes and macrophages is mediated by the major phagocytic receptor, complement receptor 3 (CR3, CD11b/CD18. We recently determined that despite a significant increase in macrophage uptake following C3 opsonization of the virulent Type A F. tularensis spp. tularensis Schu S4, this phagocytic pathway results in limited pro-inflammatory cytokine production. Notably, MAP kinase/ERK activation is suppressed immediately during C3-opsonized Schu S4-CR3 phagocytosis. A mathematical model of CR3-TLR2 crosstalk predicted early involvement of Ras GTPase-activating protein (RasGAP in immune suppression by CR3. Here, we link CR3-mediated uptake of opsonized Schu S4 by human monocytes and macrophages with inhibition of early signal 1 inflammasome activation, evidenced by limited caspase-1 cleavage and IL-18 release. This inhibition is due to increased RasGAP activity, leading to a reduction in the Ras-ERK signaling cascade upstream of the early inflammasome activation event. Thus, our data uncover a novel signaling pathway mediated by CR3 following engagement of opsonized virulent F. tularensis to limit inflammasome activation in human phagocytic cells, thereby contributing to evasion of the host innate immune system.

  10. Early decreased TLR2 expression on monocytes is associated with their reduced phagocytic activity and impaired maturation in a porcine polytrauma model

    Science.gov (United States)

    Schimunek, Lukas; Serve, Rafael; Teuben, Michel P. J.; Störmann, Philipp; Auner, Birgit; Woschek, Mathias; Pfeifer, Roman; Horst, Klemens; Simon, Tim-P.; Kalbitz, Miriam; Sturm, Ramona; Pape, Hans-C.; Hildebrand, Frank; Marzi, Ingo

    2017-01-01

    In their post-traumatic course, trauma patients suffering from multiple injuries have a high risk for immune dysregulation, which may contribute to post-injury complications and late mortality. Monocytes as specific effector cells of the innate immunity play a crucial role in inflammation. Using their Pattern Recognition Receptors (PRRs), notably Toll-Like Receptors (TLR), the monocytes recognize pathogens and/or pathogen-associated molecular patterns (PAMPs) and organize their clearance. TLR2 is the major receptor for particles of gram-positive bacteria, and initiates their phagocytosis. Here, we investigated the phagocytizing capability of monocytes in a long-term porcine severe trauma model (polytrauma, PT) with regard to their TLR2 expression. Polytrauma consisted of femur fracture, unilateral lung contusion, liver laceration, hemorrhagic shock with subsequent resuscitation and surgical fracture fixation. After induction of PT, peripheral blood was withdrawn before (-1 h) and directly after trauma (0 h), as well as 3.5 h, 5.5 h, 24 h and 72 h later. CD14+ monocytes were identified and the expression levels of H(S)LA-DR and TLR2 were investigated by flow cytometry. Additionally, the phagocytizing activity of monocytes by applying S. aureus particles labelled with pHrodo fluorescent reagent was also assessed by flow cytometry. Furthermore, blood samples from 10 healthy pigs were exposed to a TLR2-neutralizing antibody and subsequently to S. aureus particles. Using flow cytometry, phagocytizing activity was determined. P below 0.05 was considered significant. The number of CD14+ monocytes of all circulating leukocytes remained constant during the observational time period, while the percentage of CD14+H(S)LA-DR+ monocytes significantly decreased directly, 3.5 h and 5.5 h after trauma. The percentage of TLR2+ expressing cells out of all monocytes significantly decreased directly, 3.5 h and 5.5 h after trauma. The percentage of phagocytizing monocytes decreased

  11. A pharmacologic study on the mechanism of action of Kakkon-to: body temperature elevation and phagocytic activation of macrophages in dogs.

    Science.gov (United States)

    Muraoka, Kenichi; Yoshida, Satoshi; Hasegawa, Kazumasa; Nakanishi, Nobuo; Fukuzawa, Isao; Tomita, Akio; Cyong, Jong Chol

    2004-10-01

    The phagocytic activity of macrophages as a novel approach to scientific elucidation of the effects of Chinese medicines was studied through administration of a kampo preparation, by measuring the rise in body temperature, which is thought to stimulate innate defensive functions of organisms and enhance the immune systems. Using dogs as experimental models, a rise in body temperature following administration of Kakkon-to was observed, and the average number and average rate of phagocytosis of macrophages in blood using latex micro-particles was investigated. The body temperature of the treated animals significantly increased 30 minutes after administration (ptemperatures before and after administration showed significant increases over controls from 1 to 11 hours, ptemperature but also enhances the phagocytic activity of macrophages, an in vivo defense mechanism, suggesting that Kakkon-to contributes to the suppression of multiplication of common cold viruses and influenza viruses, which consequently results in improvement of various symptoms during infection with common cold viruses.

  12. Dynamics of the changes in the number and phagocytic activity of leucocytes from whole-body gamma-irradiated guinea pigs with respect to R and S forms of Pseudomonas pseudomallei

    International Nuclear Information System (INIS)

    Najdenski, Kh.M.; Velyanov, D.K.

    1987-01-01

    Guinea pigs of both sexes received whole-body gamma irradiation (0.5 Gy, 4 x 0.5 Gy and 2 Gy; 92.5 rad/min). Two bacterial strains were used: Ps. pseudomallei R 1 5 and S 7 . The measurments were carried out on days 1, 3, 7, 15 and 30 after treatment. The changes observed were directly dependent on the dose applied: for sublethally (2 Gy) irradiated animals - an abrupt decrease of leukocytes and strongly expressed leukopenia lasting throughout the whole investigation; for fractiionally irradiated (4 x 0.5 Gy) -the number of leukocytes P<0.001 and leukopenia being observed to day 7 after irradiation; for 0.5 Gy irradiated -the leucocytes number equal to that of the controls on day 15 and significantly higher on day 30; less strongly expressed leukopenia. The alterations in phagocytic activity in relation to R and S forms of Ps. pseudomallei were similar: leukocytes from 2 Gy irradiated guinea pigs showed on day 1 a markedly raised phagocytic activity and phagocytized the R and S forms to a similar degree, while at later intervals of the study the phagocytic activity decreased and they began to phagocytize the R forms more actively. Leukocytes from 0.5 Gy treated animals phagocytized the R forms more actively than the S forms throughout the whole investigation

  13. [EFFICIENCY OF COMBINATION OF ROFLUMILAST AND QUERCETIN FOR CORRECTION OXYGEN- INDEPENDENT MECHANISMS AND PHAGOCYTIC ACTIVITY OF MACROPHAGE CELLS OF PATIENTS WITH ACUTE EXACERBATION OF CHRONIC OBSTRUCTIVE PULMONARY DISEASE WHEN COMBINED WITH CORONARY HEART DISEASE].

    Science.gov (United States)

    Gerych, P; Yatsyshyn, R

    2015-01-01

    Studied oxygen independent reaction and phagocytic activity of macrophage cells of patients with chronic obstructive pulmonary disease (COPD) II-III stage when combined with coronary heart disease (CHD). The increasing oxygen independent reactions monocytes and neutrophils and a decrease of the parameters that characterize the functional state of phagocytic cells, indicating a decrease in the functional capacity of macrophage phagocytic system (MPS) in patients with acute exacerbation of COPD, which runs as its own or in combination with stable coronary heart disease angina I-II. FC. Severity immunodeficiency state in terms of cellular component of nonspecific immunity in patients with acute exacerbation of COPD II-III stage in conjunction with the accompanying CHD increases with the progression of heart failure. Inclusion of basic therapy of COPD exacerbation and standard treatment of coronary artery disease and drug combinations Roflumilastand quercetin causes normalization of phagocytic indices MFS, indicating improved immune status and improves myocardial perfusion in terms of daily ECG monitoring.

  14. Anti-Pseudomonas aeruginosa IgY antibodies promote bacterial opsonization and augment the phagocytic activity of polymorphonuclear neutrophils

    DEFF Research Database (Denmark)

    Thomsen, Kim; Christophersen, Lars; Jensen, Peter Østrup

    2016-01-01

    Moderation of polymorphonuclear neutrophils (PMNs) as part of a critical defense against invading pathogens may offer a promising therapeutic approach to supplement the antibiotic eradication of Pseudomonas aeruginosa infection in non-chronically infected cystic fibrosis (CF) patients. We have...... observed that egg yolk antibodies (IgY) harvested from White leghorn chickens that target P. aeruginosa opsonize the pathogen and enhance the PMN-mediated respiratory burst and subsequent bacterial killing in vitro. The effects on PMN phagocytic activity were observed in different Pseudomonas aeruginosa...

  15. The immunomodulatory effect of Zingiber cassumunar ethanolic extract on phagocytic activity, nitrit oxide and reaxtive oxygen intermediate secretions of macrophage in mice

    Science.gov (United States)

    Nurkhasanah; Santoso, R. D.; Fauziah, R.

    2017-11-01

    Immunomodulators could protect the body from a variety of infectious agents and boost immunity. Zingiber cassumunar rhizome or bangle potentially showed as an immunomodulator through increasing of macrophage activity in vitro. The objective of the study was to determine the effect of Z. cassumunar rhizome ethanolic extract on phagocytic activity, nitrite oxide (NO) and reactive oxygen intermediate (ROI) secretions in macrophages in vivo. A total of 200 g of Z. cassumunar rhizome was powdered, macerated in 96% ethanol and evaporated to get concentrated extract. Mice were divided into 5 groups as follow: the normal group was given by water only, the negative control group was given by a 0.94% CMC-Na suspension, the treatment groups were given by 250, 500 and 1000 mg/kgBW, respectively, of Z. cassumunar ethanolic extract. The extract was administered orally for 7 days. On the 8th day the mice were injected intraperitoneally 0.7 mg/kg BW of lipopolysaccharide. Four hours later macrophage was isolated. Furthermore, the determination of the phagocytic activity, NO and ROI secretions levels of macrophage were performed. The treatments of 250, 500 and 1000 mg/kg BW of Z. cassumunar ethanolic extract significantly increase the ROI and NO secretions levels (p0.05) of macrophage. Z. cassumunar ethanolic extract have immunomodulatory effect in vivo.

  16. Cellular defense of the avian respiratory system: effects of Pasteurella multocida on respiratory burst activity of avian respiratory tract phagocytes.

    Science.gov (United States)

    Ochs, D L; Toth, T E; Pyle, R H; Siegel, P B

    1988-12-01

    The respiratory tract of healthy chickens contain few free-residing phagocytic cells. Intratracheal inoculation with Pasteurella multocida stimulated a significant (P less than 0.05) migration of cells to the lungs and air sacs of White Rock chickens within 2 hours after inoculation. We found the maximal number of avian respiratory tract phagocytes (22.9 +/- 14.0 x 10(6] at 8 hours after inoculation. Flow cytometric analysis of these cells revealed 2 populations on the basis of cell-size and cellular granularity. One of these was similar in size and granularity to those of blood heterophils. Only this population was capable of generating oxidative metabolites in response to phorbol myristate acetate. The ability of the heterophils to produce hydrogen peroxide, measured as the oxidation of intracellularly loaded 2',7'-dichlorofluorescein, decreased with time after inoculation. These results suggest that the migration of heterophils, which are capable of high levels of oxidative metabolism, to the lungs and air sacs may be an important defense mechanism of poultry against bacterial infections of the respiratory tract.

  17. Heterophil Phagocytic Activity Stimulated by Lactobacillus salivarius L61 and L55 Supplementation in Broilers with Salmonella Infection.

    Science.gov (United States)

    Sornplang, Pairat; Leelavatcharamas, Vichai; Soikum, Chaiyaporn

    2015-11-01

    Newborn chicks are susceptible to Salmonella enterica serovar Enteritidis (SE). The objective of this study was to evaluate the effect of Lactobacillus probiotic isolated from chicken feces on heterophil phagocytosis in broiler chicks. A total of 150 newborn broiler chicks were divided into 5 groups (30 chicks per group) as follows: group 1 (normal control), given feed and water only, group 2 (positive control) given feed, water and SE infection, group 3 (L61 treated) given feed, water, SE infection followed by Lactobacillus salivarius L61 treatment, group 4 (L55 treated) given feed, water, SE infection followed by L. salivarius L55 treatment, and group 5 given feed, water, SE infection followed by L. salivarius L61 + L55 combination treatment. After SE infection, L. salivarius treatment lasted for 7 days. The results showed that L. salivarius L61 and L. salivarius L55 treatment, either alone or combination of both, increased the survival rate after SE infection, and upregulated heterophil phagocytosis and phagocytic index (PI). Conversely, chick groups treated with Lactobacillus showed lower SE recovery rate from cecal tonsils than that of the positive control group. The PI values of the chicken group with SE infection, followed by the combination of L. salivarius L61 and L. salivarius L55 were the highest as compared to either positive control or normal control group. Two Lactobacillus strains supplementation group showed significantly (p<0.05) higher PI value at 48 h than 24 h after treatment.

  18. A primary study on the phagocytic activity of Kupffer cells with superparamagnetic iron oxide particles enhanced MR imaging in a rat nonalcoholic steatohepatitis model

    International Nuclear Information System (INIS)

    Jiao Zhiyun; Li Cheng; Ma Zhanlong; Chen Wenjuan

    2010-01-01

    Objective: To investigate the feasibility of using superparamgnetic iron oxide (SPIO) as MRI contrast agent to assess rat nonalcoholic steatohepatitis Kupffer cells (KC) function. Methods: Twenty male SD rats were randomly divided into A and B groups, group A (n=10) was the experimental group fed high fat diet, group B (n=10) was the control group fed normal diet. After 8 weeks, plain MR and SPIO enhanced MR were performed in all the rats. Blood lipids were measured, and HE and Perl's blue staining in all livers specimen was done. The related results of the staining were analyzed with t test. Results: Group A TC and TG levels [(6.58 ± 1.25) and (1.53 ± 0.23) mmol/L respectively] were significantly higher than group B[(1.64 ± 0.22) and (0.55 ± 0.14) mmol/L respectively] (t=11.716 and 11.588, P 1 WI, ad statistically significant differences (t=-18.451 and -16.240, P 2 WI, T 2 WI and T 1 WI (t=10.745, 19.800, 39.168 and 92.785, P<0.01). Typical histological hepatic lesions of NASH were observed in group A, Perl's staining-positive particles in group A (2.33 ± 0.50) were fewer than in group B (4) (t=-10.000, P<0.01). Conclusion: The high-fat diet induced model of SD rats was close to the human NASH and was easy to establish. Clinical application of SPIO enhanced MR successfullly assessed the phagocytic activity of KC in the study, and it suggested that the pathogenesis of NASH was related to the decreased phagocytic activity of KC. (authors)

  19. Plasmodium and mononuclear phagocytes.

    Science.gov (United States)

    Mac-Daniel, Laura; Ménard, Robert

    2015-01-01

    Plasmodium, the causative agent of malaria, initially multiplies inside liver cells and then in successive cycles inside erythrocytes, causing the symptoms of the disease. In this review, we discuss interactions between the extracellular and intracellular forms of the Plasmodium parasite and innate immune cells in the mammalian host, with a special emphasis on mononuclear phagocytes. We overview here what is known about the innate immune cells that interact with parasites, mechanisms used by the parasite to evade them, and the protective or detrimental contribution of these interactions on parasite progression through its life cycle and pathology in the host. Copyright © 2014 Elsevier Ltd. All rights reserved.

  20. Sensor Fusion for Nuclear Proliferation Activity Monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Adel Ghanem, Ph D

    2007-03-30

    The objective of Phase 1 of this STTR project is to demonstrate a Proof-of-Concept (PoC) of the Geo-Rad system that integrates a location-aware SmartTag (made by ZonTrak) and a radiation detector (developed by LLNL). It also includes the ability to transmit the collected radiation data and location information to the ZonTrak server (ZonService). The collected data is further transmitted to a central server at LLNL (the Fusion Server) to be processed in conjunction with overhead imagery to generate location estimates of nuclear proliferation and radiation sources.

  1. Influence of platelet-activating factor receptor (PAFR) on Brucella abortus infection: implications for manipulating the phagocytic strategy of B. abortus.

    Science.gov (United States)

    Lee, Jin Ju; Simborio, Hannah Leah; Reyes, Alisha Wehdnesday Bernardo; Hop, Huynh Tan; Arayan, Lauren Togonon; Lee, Hu Jang; Min, Wongi; Her, Moon; Rhee, Man Hee; Watarai, Masahisa; Chang, Hong Hee; Kim, Suk

    2016-04-21

    Brucella abortus is an intracellular pathogen which can infect and persist in host cells through multiple interactions. Above all, its interaction to host cell receptor is important to understand the pathogenic mechanisms of B. abortus. Accordingly, we demonstrated that platelet-activating factor receptor (PAFR) affects host cell response against B. abortus infection. First of all, B. abortus infection to macrophage induces secretion of platelet-activating factor (PAF), which is a PAFR agonist. The stimulation of PAFR by PAF remarkably increases B. abortus uptake into macrophages. It induces Janus kinase 2 (JAK2) and p38α phosphorylation, indicating that PAFR-mediated activation of JAK2 signaling leads to enhanced uptake of B. abortus. Moreover, the dynamics of F-actin polymerization revealed that PAFR-mediated B. abortus uptake is related with the reorganization of F-actin and JAK2. Upon B. abortus phagocytosis, reduced PAFR in the membrane and subsequently increased levels of PAFR colocalization with endosomes were observed which indicate that B. abortus uptake into macrophages allowed PAFR trafficking to endosomes. This study demonstrated that PAFR has a compelling involvement in B. abortus uptake as a promoter of phagocytosis, which is associated with JAK2 activation. Thus, our findings establish a novel insight into a receptor-related phagocytic mechanism of B. abortus.

  2. Defect Proliferation in Active Nematic Suspensions

    Science.gov (United States)

    Mishra, Prashant; Bowick, Mark J.; Giomi, Luca; Marchetti, M. Cristina

    2014-03-01

    The rich structure of equilibrium nematic suspensions, with their characteristic disclination defects, is modified when active forces come into play. The uniform nematic state is known to be unstable to splay (extensile) or bend (contractile) deformations above a critical activity. At even higher activity the flow becomes oscillatory and eventually turbulent. Using hydrodynamics, we classify the active flow regimes as functions of activity and order parameter friction for both contractile and extensile systems. The turbulent regime is marked by a non-zero steady state density of mobile defect pairs. The defect density itself scales with an ``active Ericksen number,'' defined as the ratio of the rate at which activity is injected into the system to the relaxation rate of orientational deformations. The work at Syracuse University was supported by the NSF on grant DMR-1004789 and by the Syracuse Soft Matter Program.

  3. Inhibitory effect of red ginseng acidic polysaccharide from Korean red ginseng on phagocytic activity and intracellular replication of Brucella abortus in RAW 264.7 cells.

    Science.gov (United States)

    Reyes, Alisha Wehdnesday Bernardo; Simborio, Hannah Leah Tadeja; Hop, Huynh Tan; Arayan, Lauren Togonon; Min, Won Gi; Lee, Hu Jang; Rhee, Man Hee; Chang, Hong Hee; Kim, Suk

    2016-09-30

    Korean red ginseng (KRG) has long been used in traditional Korean and Oriental medicine. However, the anti-bacterial mechanism and therapeutic efficiency of KGR for intracellular Brucella infection are still unclear. In this study, the bactericidal activity of Korean red ginseng acidic polysaccharide (RGAP) on Brucella (B.) abortus and its cytotoxic effects on RAW 264.7 cells were evaluated. In addition, B. abortus internalization and intracellular replication in macrophages were investigated after RGAP treatment. RGAP-incubated cells displayed a marked reduction in the adherence, internalization and intracellular growth of B. abortus in macrophages. Furthermore, decreased F-actin fluorescence was observed relative to untreated B. abortus-infected cells. Western blot analysis of intracellular signaling proteins revealed reduced ERK, JNK and p38α phosphorylation levels in B. abortus-infected RGAP-treated cells compared to the control. Moreover, elevated co-localization of B. abortus-containing phagosomes with lysosome-associated membrane protein 1 (LAMP-1) were observed in RGAP-treated cells compared with the control. Overall, the results of this study suggest that RGAP can disrupt phagocytic activity of B. abortus via suppression of mitogen-activated protein kinases (MAPKs) signaling proteins ERK, JNK and p38 levels and inhibit intracellular replication of B. abortus by enhancing phagolysosome fusion, which may provide an alternative control of brucellosis.

  4. Resveratrol Protects Against Ultraviolet A-Mediated Inhibition of the Phagocytic Function of Human Retinal Pigment Epithelial Cells Via Large-Conductance Calcium-Activated Potassium Channels

    Directory of Open Access Journals (Sweden)

    Shwu-Jiuan Sheu

    2009-07-01

    Full Text Available This study was undertaken to examine the protective effect of resveratrol on human retinal pigment epithelial (RPE cell phagocytosis against ultraviolet irradiation damage. Cultured RPE cells were exposed to ultraviolet A (UVA, 20 minutes irradiation, and treated with meclofenamic acid (30μM, 20 minutes, paxilline (100 μM, 20 minutes or resveratrol (10μM, 20 minutes. Meclofenamic acid and resveratrol were given after exposure to UVA. Pretreatment with meclofenamic acid, resveratrol or paxilline before UVA irradiation was also performed. Fluorescent latex beads were then fed for 4 hours and the phagocytotic function was assessed by flow cytometry. UVA irradiation inhibited the phagocytic function of human RPE cells. The large-conductance calcium-activated potassium channel activator meclofenamic acid ameliorated the damage caused by UVA irradiation. Pretreatment with resveratrol acid also provided protection against damage caused by UVA. Posttreatment with meclofenamic acid offered mild protection, whereas resveratrol did not. In conclusion, the red wine flavonoid resveratrol ameliorated UVA-mediated inhibition of human RPE phagocytosis. The underlying mechanism might involve the large-conductance calcium-activated potassium channels.

  5. Survival and function of phagocytes in blood culture media

    DEFF Research Database (Denmark)

    Fischer, T K; Prag, J; Kharazmi, A

    1999-01-01

    The survival and function of human phagocytes in sterile aerobic and anaerobic blood culture media were investigated using neutrophil morphology, white blood cell count in a haemoanalyser, flow cytometry, oxidative burst response, and bactericidal effect in Colorbact and Septi-Chek blood culture...... media and Bact/Alert. When comparing agitation to stationary incubation no difference in phagocytic activity was found. The methods showed the same trends demonstrating that the phagocytes' viability and activity were prolonged by oxygen and shortened by anaerobic conditions and sodium polyethanol...... sulfonate (SPS). Best preserved activity and viability were found in the aerobic media containing less than 0.5 g/l SPS, in which significant phagocyte oxidative burst and bactericidal activity were found up to 4 days after inoculation. Considering that the majority of bacteremias are due to aerobic...

  6. The effect of beta-hydroxy-beta-methylbutyrate (HMB) on the proliferative response of blood lymphocytes and the phagocytic activity of blood monocytes and granulocytes in calves.

    Science.gov (United States)

    Wójcik, R; Małaczewska, J; Siwicki, A K; Miciński, J; Zwierzchowski, G

    2013-01-01

    The objective of this study was to evaluate the effect of HMB on selected indicators of immunity in calves. The experiment was performed on 14 calves aged 30 +/- 2 days, divided into two equal groups of control (group I) and experimental (group II) animals. The feed administered to experimental group calves was supplemented with HMB at 40 mg/kg BW, whereas control calves were administered standard farm-made feed without supplementation. Blood was sampled from the jugular vein immediately before the experiment (day 0) and on experimental days 15, 30 and 60 to determine the following parameters of immunity: proliferative response of LPS- and ConA-stimulated lymphocytes (MTT), respiratory burst activity (RBA) and potential killing activity (PKA) of phagocytes. The results revealed a significant increase in RBA and MTT values in calves administered HMB in comparison with the control group throughout the experiment. In the group of animals receiving HMB, an increase in PKA values was noted only on day 30.

  7. Decreased Fc receptor expression on innate immune cells is associated with impaired antibody-mediated cellular phagocytic activity in chronically HIV-1 infected individuals.

    Science.gov (United States)

    Dugast, Anne-Sophie; Tonelli, Andrew; Berger, Christoph T; Ackerman, Margaret E; Sciaranghella, Gaia; Liu, Qingquan; Sips, Magdalena; Toth, Ildiko; Piechocka-Trocha, Alicja; Ghebremichael, Musie; Alter, Galit

    2011-07-05

    In addition to neutralization, antibodies mediate other antiviral activities including antibody-dependent cellular phagocytosis (ADCP), antibody-dependent cellular cytotoxicity (ADCC), as well as complement deposition. While it is established that progressive HIV infection is associated with reduced ADCC and ADCP, the underlying mechanism for this loss of function is unknown. Here we report considerable changes in FcR expression over the course of HIV infection on both mDCs and monocytes, including elevated FcγRI expression in acute HIV infection and reduced expression of FcγRII and FcγRIIIa in chronic HIV infection. Furthermore, selective blockade of FcγRII alone was associated with a loss in ADCP activity, suggesting that FcγRII plays a central role in modulating ADCP. Overall, HIV infection is associated with a number of changes in FcR expression on phagocytic cells that are associated with changes in their ability to respond to antibody-opsonized targets, potentially contributing to a failure in viral clearance in progressive HIV-1 infection. Copyright © 2011 Elsevier Inc. All rights reserved.

  8. Decreased Fc-Receptor expression on innate immune cells is associated with impaired antibody mediated cellular phagocytic activity in chronically HIV-1 infected individuals

    Science.gov (United States)

    Dugast, Anne-Sophie; Tonelli, Andrew; Berger, Christoph T.; Ackerman, Margaret E.; Sciaranghella, Gaia; Liu, Qingquan; Sips, Magdalena; Toth, Ildiko; Piechocka-Trocha, Alicja; Ghebremichael, Musie; Alter, Galit

    2011-01-01

    In addition to neutralization, antibodies mediate other antiviral activities including antibody-dependent cellular-phagocytosis (ADCP), antibody dependent cellular-cytotoxicity (ADCC), as well as complement deposition. While it is established that progressive HIV infection is associated with reduced ADCC and ADCP, the underlying mechanism for this loss of function is unknown. Here we report considerable changes in FcR expression over the course of HIV infection on both mDCs and monocytes, including elevated FcγRI expression in acute HIV infection and reduced expression of FcγRII and FcγRIIIa in chronic HIV infection. Furthermore, selective blockade of FcγRII alone was associated with a loss in ADCP activity, suggesting that FcγRII plays a central role in modulating ADCP. Overall, HIV infection is associated with a number of changes in FcR expression on phagocytic cells that are associated with changes in their ability to respond to antibody-opsonized targets, potentially contributing to a failure in viral clearance in progressive HIV-1 infection. PMID:21565376

  9. INFLUENCE OF LOCAL RONKOLEIKIN TREATMENT UPON CLINICAL COURSE OF PURULENT WOUNDS AND FUNCTIONAL ACTIVITY OF WOUND PHAGOCYTES IN PATIENTS WITH ODONTOGENIC PHLEGMONAE

    Directory of Open Access Journals (Sweden)

    I. I. Dolgushin

    2009-01-01

    Full Text Available Abstract. The aim of the work was to evaluate clinical features of purulent wounds trend and functional activity of local wound phagocytes in the patients with odontogenic phlegmones in the course of local treatment with Ronkoleukin. A randomized clinical study was performed which included sixty-five patients with odontogenic phlegmones. Their age ranged from 18 to 74 years old. The group was divided in two parts, i.e., patients of a comparison group (n = 33 receiving a conventional combined drug therapy, and the persons from study group (n = 32 who were subject to local immunotherapy with Ronkoleukin, applied along with conventional therapy. It was established that the local therapy with Ronkoleikin exerts distinct positive effects, i.e., increase in wound-located lymphocytes and macrophages, acceleration of phasic dynamics of inflammatory events, augmentation of an lysosomal luminescence index (2.3-fold, enhancement of phagocytosis intensity in wound neutrophiles and macrophages (1.9-2-fold, strengthening the reserve abilities of wound neutrophils (1.3-fold. These effects create favorable conditions for elimination of pathogen and optimal healing of purulent wounds in the patients with odontogenic phlegmones.

  10. CCR1+/CCR5+ mononuclear phagocytes accumulate in the central nervous system of patients with multiple sclerosis

    DEFF Research Database (Denmark)

    Trebst, C; Sørensen, Torben Lykke; Kivisäkk, P

    2001-01-01

    Mononuclear phagocytes (monocytes, macrophages, and microglia) are considered central to multiple sclerosis (MS) pathogenesis. Molecular cues that mediate mononuclear phagocyte accumulation and activation in the central nervous system (CNS) of MS patients may include chemokines RANTES/CCL5...

  11. Autophagy Proteins in Phagocyte Endocytosis and Exocytosis

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    Christian Münz

    2017-09-01

    Full Text Available Autophagy was initially described as a catabolic pathway that recycles nutrients of cytoplasmic constituents after lysosomal degradation during starvation. Since the immune system monitors products of lysosomal degradation via major histocompatibility complex (MHC class II restricted antigen presentation, autophagy was found to process intracellular antigens for display on MHC class II molecules. In recent years, however, it has become apparent that the molecular machinery of autophagy serves phagocytes in many more membrane trafficking pathways, thereby regulating immunity to infectious disease agents. In this minireview, we will summarize the recent evidence that autophagy proteins regulate phagocyte endocytosis and exocytosis for myeloid cell activation, pathogen replication, and MHC class I and II restricted antigen presentation. Selective stimulation and inhibition of the respective functional modules of the autophagy machinery might constitute valid therapeutic options in the discussed disease settings.

  12. In vitro formation of osteoclasts from long-term cultures of bone marrow mononuclear phagocytes

    International Nuclear Information System (INIS)

    Burger, E.H.; Van der Meer, J.W.; van de Gevel, J.S.; Gribnau, J.C.; Thesingh, G.W.; van Furth, R.

    1982-01-01

    The origin of osteoclasts was studied in an in vitro model using organ cultures of periosteum-free embryonic mouse long-bone primordia, which were co-cultured with various cell populations. The bone rudiments were freed of their periosteum-perichondrium by collagenase treatment in a stage before cartilage erosion and osteoclast formation, and co-cultured for 7 d with either embryonic liver or mononuclear phagocytes from various sources. Light and electron microscopic examination of the cultures showed that mineralized matrix-resorbing osteoclasts developed only in bones co-cultured with embryonic liver or with cultured bone marrow mononuclear phagocytes but not when co-cultured with blood monocytes or resident or exudate peritoneal macrophages. Osteoclasts developed from the weakly adherent, but not from the strongly adherent cells of bone marrow cultures, whereas 1,000 rad irradiation destroyed the capacity of such cultures to form osteoclasts. In bone cultures to which no other cells were added, osteoclasts were virtually absent. Bone-resorbing activity of in vitro formed osteoclasts was demonstrated by 45 Ca release studies. These studies demonstrate that osteoclasts develop from cells present in cultures of proliferating mononuclear phagocytes and that, at least in our system, monocytes and macrophages are unable to form osteoclasts. The most likely candidates for osteoclast precursor cells seem to be monoblasts and promonocytes

  13. Leishmania mexicana amazonensis: heterogeneity in 5-nucleotidase and peroxidase activities of mononuclear phagocytes during in vivo and in vitro infection Leishmania mexicana amazonensis: heterogeneidade da 5’-Nucleotidase e da peroxidase em fagócitos mononucleares durante infecção in vivo e in vitro

    OpenAIRE

    Suzana Côrte-Real; Gabriel Grimaldi Junior; Maria de Nazareth Leal de Meirelles

    1988-01-01

    The degree of maturation of cells of the Mononuclear Phagocyte System (MPS), during in vivo and in vitro infection by Leishmania mexicana amazonenesis, was evaluated in this study. The macrophages' differentiation was assayed by cytochemical characterization at the ultrastrctural level, using two well-established markers: 5'-nucleotidase enzyme activity, for revealing the mature cells, and the peroxidase activity present in the cell granules to demonstrate immature mononuclear phagocytes. onl...

  14. Rac1 activity regulates proliferation of aggressive metastatic melanoma

    International Nuclear Information System (INIS)

    Bauer, Natalie N.; Chen Yihwen; Samant, Rajeev S.; Shevde, Lalita A.; Fodstad, Oystein

    2007-01-01

    Molecular mechanisms underlying the different capacity of two in vivo selected human melanoma cell variants to form experimental metastases were studied. The doubling times of the FEMX-I and FEMX-V cell sublines in vitro were 15 and 25 h, respectively. The invasive capacity of FEMX-I cells was 8-fold higher than FEMX-V cells, and the time to form approximately 10 mm s.c. tumors in nude mice was 21 versus 35 days. FEMX-I displayed a spindle-like formation in vitro, whereas FEMX-V cells had a rounded shape. Hence, we examined known determinants of cell shape and proliferation, the small GTPases. The four studied showed equal expression in both cell types, but Rac1 activity was significantly decreased in FEMX-V cells. Rac1 stimulates NFκB, and we found that endogenous NFκB activity of FEMX-V cells was 2% of that of FEMX-I cells. Inhibition of Rac1 resulted in blocked NFκB activity. Specific inhibition of either Rac1 or NFκB significantly reduced proliferation and invasion of FEMX-I cells, the more pronounced effects observed with Rac1 inhibition. These data indicate that Rac1 activity in FEMX cells regulates cell proliferation and invasion, in part via its effect on NFκB, signifying Rac1 as a key molecule in melanoma progression and metastasis

  15. Peroxisome proliferator-activated receptor delta activation leads to increased transintestinal cholesterol efflux

    NARCIS (Netherlands)

    Vrins, Carlos L. J.; van der Velde, Astrid E.; van den Oever, Karin; Levels, Johannes H. M.; Huet, Stephane; Elferink, Ronald P. J. Oude; Kuipers, Folkert; Groen, Albert K.

    2009-01-01

    Peroxisome proliferator-activated receptor delta (PPAR delta) is involved in regulation of energy homeostasis. Activation of PPAR delta markedly increases fecal neutral sterol secretion, the last step in reverse cholesterol transport. This phenomenon can neither be explained by increased

  16. Peroxisome proliferator-activated receptor delta activation leads to increased transintestinal cholesterol efflux

    NARCIS (Netherlands)

    Vrins, Carlos L. J.; van der Velde, Astrid E.; van den Oever, Karin; Levels, Johannes H. M.; Huet, Stephane; Oude Elferink, Ronald P. J.; Kuipers, Folkert; Groen, Albert K.

    2009-01-01

    Peroxisome proliferator-activated receptor delta (PPARdelta) is involved in regulation of energy homeostasis. Activation of PPARdelta markedly increases fecal neutral sterol secretion, the last step in reverse cholesterol transport. This phenomenon can neither be explained by increased hepatobiliary

  17. Cell proliferation in vitro modulates fibroblast collagenase activity

    International Nuclear Information System (INIS)

    Lindblad, W.J.; Flood, L.

    1986-01-01

    Collagenase enzyme activity is regulated by numerous control mechanisms which prevent excessive release and activation of this protease. A primary mechanism for regulating enzyme extracellular activity may be linked to cell division, therefore they have examined the release of collagenase by fibroblasts in vitro in response to cellular proliferation. Studies were performed using fibroblasts derived from adult rat dermis maintained in DMEM containing 10% newborn calf serum, 25 mM tricine buffer, and antibiotics. Cells between subculture 10 and 19 were used with enzyme activity determined with a 14 C-labelled soluble Type I collagen substrate with and without trypsin activation. Fibroblasts, trypsinized and plated at low density secreted 8.5 fold more enzyme than those cells at confluence (975 vs. 115 dpm/μg DNA). This diminution occurred gradually as the cells went from logrithmic growth towards confluence. Confluent fibroblast monolayers were scraped in a grid arrangement, stimulating the remaining cells to divide, without exposure to trypsin. Within 24-48 hr postscraping enzyme levels had increased 260-400%, accompanied by enhanced incorporation of 3 H-thymidine and 3 H-uridine into cell macromolecules. The burst of enzyme release began to subside 12 hr later. These results support a close relationship between fibroblast proliferation and collagenase secretion

  18. Peroxisome Proliferator-Activated Receptor Alpha Target Genes

    Directory of Open Access Journals (Sweden)

    Maryam Rakhshandehroo

    2010-01-01

    Full Text Available The peroxisome proliferator-activated receptor alpha (PPARα is a ligand-activated transcription factor involved in the regulation of a variety of processes, ranging from inflammation and immunity to nutrient metabolism and energy homeostasis. PPARα serves as a molecular target for hypolipidemic fibrates drugs which bind the receptor with high affinity. Furthermore, PPARα binds and is activated by numerous fatty acids and fatty acid-derived compounds. PPARα governs biological processes by altering the expression of a large number of target genes. Accordingly, the specific role of PPARα is directly related to the biological function of its target genes. Here, we present an overview of the involvement of PPARα in lipid metabolism and other pathways through a detailed analysis of the different known or putative PPARα target genes. The emphasis is on gene regulation by PPARα in liver although many of the results likely apply to other organs and tissues as well.

  19. Nanoparticles of barium induce apoptosis in human phagocytes.

    Science.gov (United States)

    Mores, Luana; França, Eduardo Luzia; Silva, Núbia Andrade; Suchara, Eliane Aparecida; Honorio-França, Adenilda Cristina

    2015-01-01

    Nutrients and immunological factors of breast milk are essential for newborn growth and the development of their immune system, but this secretion can contain organic and inorganic toxins such as barium. Colostrum contamination with barium is an important issue to investigate because this naturally occurring element is also associated with human activity and industrial pollution. The study evaluated the administration of barium nanoparticles to colostrum, assessing the viability and functional activity of colostral mononuclear phagocytes. Colostrum was collected from 24 clinically healthy women (aged 18-35 years). Cell viability, superoxide release, intracellular Ca(2+) release, and phagocyte apoptosis were analyzed in the samples. Treatment with barium lowered mononuclear phagocyte viability, increased superoxide release, and reduced intracellular calcium release. In addition, barium increased cell death by apoptosis. These data suggest that nanoparticles of barium in colostrum are toxic to cells, showing the importance of avoiding exposure to this element.

  20. Effects of 6-methyl-uracil upon the phagocytic activity in mice following whole-body X-irradiation or 2,4,6,-triethyleneimino-s-triazine treatment

    International Nuclear Information System (INIS)

    Raake, W.; Tempel, K.

    1977-01-01

    1. Phagocytic activity measured by means of the intravasal clearence of a soot dispersion in male NMRI-mice was increased six to ten days after whole-body X-irradiation (640 R) and decreased during the same period after i.v. administration of 2,4,6-triethyleneimino-s-triazine (TEM 2.0 mg/kg). 2. By means of 6-methyl-uracil food admixtures (200 to 400 ppm during 2 or 3 weeks) or by repeated intravenous injections of a N-methyl-D-glucosamine-6-methyluracil complex (62.5 to 250 mg/kg daily during five days), a significant augmentation of the phagocytic index being related to time and dosage was obtained in otherwise untreated mice. Comparable results were seen using cytidine and cytidine-5'-phosphate, whereas guanosine-5'-phosphate remained ineffective. 3. Whilst stimulating effects of 6-methyl-uracil or its N-methyl-D-glucosamine complex on X-irradiated mice were suspended, an increase up to supernormal values of the phagocytic index was produced by the pyrimidine base in animals treated with TEM. In accordance to this the survival rate of lethally X-irradiated mice (960 R) could not be increased; with animals given lethal TEM-doses, however, a significantly increased survival rate was obtained. 4. The present investigations as well as former biochemical analyses confirm the assumption that 6-methyluracil produces its regeneration effects, to some extent at least, by specific pathways influencing the reticuloendothelium. Different results from X-irradiated and TEM-treated mice are referring to the different points of attack of the two noxa. (orig.) [de

  1. In vivo evaluation of the antibacterial capacity of tissue phagocytes

    International Nuclear Information System (INIS)

    Guerra, H.

    1975-01-01

    The phagocytic activity of guinea pig liver to deal with bacterial infection was investigated on 14 C- or 32 P-labelled Brucella melitensis. Some in vitro work has been started, using immunoglobulins (IgG, IgM) with antibody activity against whole Brucella

  2. Quantifying Detection Probabilities for Proliferation Activities in Undeclared Facilities

    International Nuclear Information System (INIS)

    Listner, C.; Canty, M.; Niemeyer, I.; Rezniczek, A.; Stein, G.

    2015-01-01

    International Safeguards is currently in an evolutionary process to increase effectiveness and efficiency of the verification system. This is an obvious consequence of the inability to detect the Iraq's clandestine nuclear weapons programme in the early 90s. By the adoption of the Programme 93+2, this has led to the development of Integrated Safeguards and the State-level concept. Moreover, the IAEA's focus was extended onto proliferation activities outside the State's declared facilities. The effectiveness of safeguards activities within declared facilities can and have been quantified with respect to costs and detection probabilities. In contrast, when verifying the absence of undeclared facilities this quantification has been avoided in the past because it has been considered to be impossible. However, when balancing the allocation of budget between the declared and the undeclared field, explicit reasoning is needed why safeguards effort is distributed in a given way. Such reasoning can be given by a holistic, information and risk-driven approach to Acquisition Path Analysis comprising declared and undeclared facilities. Regarding the input, this approach relies on the quantification of several factors, i.e., costs of attractiveness values for specific proliferation activities, potential safeguards measures and detection probabilities for these measures also for the undeclared field. In order to overcome the lack of quantification for detection probabilities in undeclared facilities, the authors of this paper propose a general verification error model. Based on this model, four different approaches are explained and assessed with respect to their advantages and disadvantages: the analogy approach, the Bayes approach, the frequentist approach and the process approach. The paper concludes with a summary and an outlook on potential future research activities. (author)

  3. The role of glutathione in lymphocyte activation and proliferation

    International Nuclear Information System (INIS)

    Messina, J.P.

    1990-01-01

    The object of this work was to establish the requirement for GSH and cystine during the activation and proliferation of human peripheral blood mononuclear cells (PBMC). In the author's initial experiments the intracellular GSH content of PBMC was altered by continuous culture or pretreatment with BSO, a specific inhibitor of GSH synthesis. His results demonstrate that, continuous culture of mitogen stimulated PBMC in the presence of BSO inhibited entry into S-phase of the cell cycle and produced a simultaneous decrease in intracellular GSH. The influence of BSO on early activation events were determined by BSO pretreatment. Extensive depletion (>90%) of the intracellular GSH level prior to mitogenic stimulation did not impair the ability of these cells to produce IL-2 and express IL-2R, indicating that GSH may not be involved in the generation and response to early activation signals. Furthermore, the removal of BSO from these cultures rapidly reversed its inhibitory effects on DNA and GSH synthesis. Cystine transport activities and metabolism by PBMC were characterized in order to examine its contributions to intracellular GSH and early activation proteins. In spite of the ability of cystine to sustain the proliferative response of PBMC, differences in the kinetics of cystine and cysteine uptake indicated that separate transport systems may be operational. Treatment with 2ME enhanced cystine uptake, but lowered the proliferative responses of these cells. Metabolic studies with [ 35 S] cystine demonstrated that mitogen stimulation of PBMC enhance cystine uptake

  4. CCL2/MCP-1 modulation of microglial activation and proliferation

    Directory of Open Access Journals (Sweden)

    Garcia-Bueno Borja

    2011-07-01

    Full Text Available Abstract Background Monocyte chemoattractant protein (CCL2/MCP-1 is a chemokine that attracts cells involved in the immune/inflammatory response. As microglia are one of the main cell types sustaining inflammation in brain, we proposed here to analyze the direct effects of MCP-1 on cultured primary microglia. Methods Primary microglia and neuronal cultures were obtained from neonatal and embryonic Wistar rats, respectively. Microglia were incubated with different concentrations of recombinant MCP-1 and LPS. Cell proliferation was quantified by measuring incorporation of bromodeoxyuridine (BrdU. Nitrite accumulation was measured using the Griess assay. The expression and synthesis of different proteins was measured by RT-PCR and ELISA. Cell death was quantified by measuring release of LDH into the culture medium. Results MCP-1 treatment (50 ng/ml, 24 h did not induce morphological changes in microglial cultures. Protein and mRNA levels of different cytokines were measured, showing that MCP-1 was not able to induce proinflammatory cytokines (IL-1β, IL6, MIP-1α, either by itself or in combination with LPS. A similar lack of effect was observed when measuring inducible nitric oxide synthase (NOS2 expression or accumulation of nitrites in the culture media as a different indicator of microglial activation. MCP-1 was also unable to alter the expression of different trophic factors that were reduced by LPS treatment. In order to explore the possible release of other products by microglia and their potential neurotoxicity, neurons were co-cultured with microglia: no death of neurons could be detected when treated with MCP-1. However, the presence of MCP-1 induced proliferation of microglia, an effect opposite to that observed with LPS. Conclusion These data indicate that, while causing migration and proliferation of microglia, MCP-1 does not appear to directly activate an inflammatory response in this cell type, and therefore, other factors may be

  5. Onset of apoprotein E secretion during differentiation of mouse bone marrow-derived mononuclear phagocytes

    International Nuclear Information System (INIS)

    Werb, Z.; Chin, J.R.

    1983-01-01

    A number of macrophage functions were sequentially expressed when the bone marrow precursors of mononuclear phagocytes differentiated in culture in the presence of a specific growth factor, colony-stimulating factor-1. The authors defined the expression of apoprotein E (ApoE), a major secreted protein of resident peritoneal macrophages, during maturation of adherent bone marrow-derived mononuclear phagocytes into macrophages. By 5 d the bone marrow macrophages were active secretory cells, but few cells contained intracellular immunoreactive ApoE, and little, if any, ApoE was secreted. ApoE secretion was initiated at 9 d, and this correlated with an increase in the percentage of macrophages containing intracellular ApoE. The onset of ApoE secretion was selective, and little change occurred in the other major secreted proteins detected by [ 35 S]methionine incorporation. In parallel, the high rate of plasminogen activator secretion, which peaked at 7 d, decreased markedly. ApoE secretion was not associated with altered expression of the macrophage surface antigen, la, or with secretion of fibronectin. Virtually all cells in independent colonies of bone marrow-derived macrophages eventually expressed ApoE. The proliferating monocyte/macrophage-like cell lines P388D1, J774.2, WHEI-3, RAW 264.1, and MGI.D + secreted little or no ApoE. These data establish that ApoE secretion is developmentally regulated

  6. Wnt activation affects proliferation, invasiveness and radiosensitivity in medulloblastoma.

    Science.gov (United States)

    Salaroli, Roberta; Ronchi, Alice; Buttarelli, Francesca Romana; Cortesi, Filippo; Marchese, Valeria; Della Bella, Elena; Renna, Cristiano; Baldi, Caterina; Giangaspero, Felice; Cenacchi, Giovanna

    2015-01-01

    Medulloblastomas (MBs) associated with the Wnt activation represent a subgroup with a favorable prognosis, but it remains unclear whether Wnt activation confers a less aggressive phenotype and/or enhances radiosensitivity. To investigate this issue, we evaluated the biological behavior of an MB cell line, UW228-1, stably transfected with human β-catenin cDNA encoding a nondegradable form of β-catenin (UW-B) in standard culture conditions and after radiation treatment. We evaluated the expression, transcriptional activity, and localization of β-catenin in the stably transfected cells using immunofluorescence and WB. We performed morphological analysis using light and electron microscopy. We then analyzed changes in the invasiveness, growth, and mortality in standard culture conditions and after radiation. We demonstrated that (A) Wnt activation inhibited 97 % of the invasion capability of the cells, (B) the growth of the UW-B cells was statistically significantly lower than that of all the other control cells (p < 0.01), (C) the mortality of irradiated UW-B cells was statistically significantly higher than that of the controls and their nonirradiated counterparts (p < 0.05), and (D) morphological features of neuronal differentiation were observed in the Wnt-activated cells. In tissue samples, the Ki-67 labeling index (LI) was lower in β-catenin-positive samples compared to non-β-catenin positive ones. The Ki-67 LI median (LI = 40) of the nuclear β-catenin-positive tumor samples was lower than that of non-nuclear β-catenin-positive samples (LI = 50), but the difference was not statistically significant. Overall, our data suggest that activation of the Wnt pathway reduces the proliferation and invasion of MBs and increases the tumor's radiosensitivity.

  7. Scrambled Eggs: Apoptotic Cell Clearance by Non-Professional Phagocytes in the Drosophila Ovary

    Directory of Open Access Journals (Sweden)

    Sandy B. Serizier

    2017-11-01

    Full Text Available For half of a century, it has been known that non-professional phagocytes, such as fibroblasts, endothelial, and epithelial cells, are capable of efferocytosis (engulfment of apoptotic cells. Non-professional phagocytes differ from professional phagocytes in the range and efficiency of engulfment. Much of the recognition and underlying signaling machinery between non-professional and professional phagocytes is the same, but it is not known how the engulfment capacity of non-professional phagocytes is controlled. Moreover, the signaling networks involved in cell corpse recognition, engulfment, and phagosome maturation are only partially understood. The Drosophila ovary provides an excellent system to investigate the regulation of phagocytic activity by epithelial cells, a major class of non-professional phagocytes. During Drosophila oogenesis, mid-stage egg chambers undergo apoptosis of the germline in response to nutrient deprivation. Epithelial follicle cells then undergo major cell shape changes and concomitantly engulf the germline material. Our previous work has established that Draper and the integrin α-PS3/β-PS heterodimer are required in follicle cells for germline cell clearance. In addition, we have characterized phagosome maturation pathways, and found that the JNK pathway amplifies the engulfment response. In this review, we discuss recent advances on the interplay between engulfment pathways in the follicular epithelium for cell clearance in the Drosophila ovary. We also provide a comparison to apoptotic cell clearance mechanisms in C. elegans and mammals, illustrating strong conservation of efferocytosis mechanisms by non-professional phagocytes.

  8. Scrambled Eggs: Apoptotic Cell Clearance by Non-Professional Phagocytes in the Drosophila Ovary.

    Science.gov (United States)

    Serizier, Sandy B; McCall, Kimberly

    2017-01-01

    For half of a century, it has been known that non-professional phagocytes, such as fibroblasts, endothelial, and epithelial cells, are capable of efferocytosis (engulfment of apoptotic cells). Non-professional phagocytes differ from professional phagocytes in the range and efficiency of engulfment. Much of the recognition and underlying signaling machinery between non-professional and professional phagocytes is the same, but it is not known how the engulfment capacity of non-professional phagocytes is controlled. Moreover, the signaling networks involved in cell corpse recognition, engulfment, and phagosome maturation are only partially understood. The Drosophila ovary provides an excellent system to investigate the regulation of phagocytic activity by epithelial cells, a major class of non-professional phagocytes. During Drosophila oogenesis, mid-stage egg chambers undergo apoptosis of the germline in response to nutrient deprivation. Epithelial follicle cells then undergo major cell shape changes and concomitantly engulf the germline material. Our previous work has established that Draper and the integrin α-PS3/β-PS heterodimer are required in follicle cells for germline cell clearance. In addition, we have characterized phagosome maturation pathways, and found that the JNK pathway amplifies the engulfment response. In this review, we discuss recent advances on the interplay between engulfment pathways in the follicular epithelium for cell clearance in the Drosophila ovary. We also provide a comparison to apoptotic cell clearance mechanisms in C. elegans and mammals, illustrating strong conservation of efferocytosis mechanisms by non-professional phagocytes.

  9. Peroxisome Proliferators-Activated Receptor (PPAR Modulators and Metabolic Disorders

    Directory of Open Access Journals (Sweden)

    Min-Chul Cho

    2008-01-01

    Full Text Available Overweight and obesity lead to an increased risk for metabolic disorders such as impaired glucose regulation/insulin resistance, dyslipidemia, and hypertension. Several molecular drug targets with potential to prevent or treat metabolic disorders have been revealed. Interestingly, the activation of peroxisome proliferator-activated receptor (PPAR, which belongs to the nuclear receptor superfamily, has many beneficial clinical effects. PPAR directly modulates gene expression by binding to a specific ligand. All PPAR subtypes (α,γ, and σ are involved in glucose metabolism, lipid metabolism, and energy balance. PPAR agonists play an important role in therapeutic aspects of metabolic disorders. However, undesired effects of the existing PPAR agonists have been reported. A great deal of recent research has focused on the discovery of new PPAR modulators with more beneficial effects and more safety without producing undesired side effects. Herein, we briefly review the roles of PPAR in metabolic disorders, the effects of PPAR modulators in metabolic disorders, and the technologies with which to discover new PPAR modulators.

  10. Role of Peroxisome Proliferator-Activated Receptors in Inflammation Control

    Directory of Open Access Journals (Sweden)

    Jihan Youssef

    2004-01-01

    Full Text Available Peroxisome proliferator-activated receptors (PPARs were discovered over a decade ago, and were classified as orphan members of the nuclear receptor superfamily. To date, three PPAR subtypes have been discovered and characterized (PPARα, β/δ, γ. Different PPAR subtypes have been shown to play crucial roles in important diseases and conditions such as obesity, diabetes, atherosclerosis, cancer, and fertility. Among the most studied roles of PPARs is their involvement in inflammatory processes. Numerous studies have revealed that agonists of PPARα and PPARγ exert anti-inflammatory effects both in vitro and in vivo. Using the carrageenan-induced paw edema model of inflammation, a recent study in our laboratories showed that these agonists hinder the initiation phase, but not the late phase of the inflammatory process. Furthermore, in the same experimental model, we recently also observed that activation of PPARδ exerted an anti-inflammatory effect. Despite the fact that exclusive dependence of these effects on PPARs has been questioned, the bulk of evidence suggests that all three PPAR subtypes, PPARα,δ,γ, play a significant role in controlling inflammatory responses. Whether these subtypes act via a common mechanism or are independent of each other remains to be elucidated. However, due to the intensity of research efforts in this area, it is anticipated that these efforts will result in the development of PPAR ligands as therapeutic agents for the treatment of inflammatory diseases.

  11. Adenylate Cyclase Toxin promotes bacterial internalisation into non phagocytic cells.

    Science.gov (United States)

    Martín, César; Etxaniz, Asier; Uribe, Kepa B; Etxebarria, Aitor; González-Bullón, David; Arlucea, Jon; Goñi, Félix M; Aréchaga, Juan; Ostolaza, Helena

    2015-09-08

    Bordetella pertussis causes whooping cough, a respiratory infectious disease that is the fifth largest cause of vaccine-preventable death in infants. Though historically considered an extracellular pathogen, this bacterium has been detected both in vitro and in vivo inside phagocytic and non-phagocytic cells. However the precise mechanism used by B. pertussis for cell entry, or the putative bacterial factors involved, are not fully elucidated. Here we find that adenylate cyclase toxin (ACT), one of the important toxins of B. pertussis, is sufficient to promote bacterial internalisation into non-phagocytic cells. After characterization of the entry route we show that uptake of "toxin-coated bacteria" proceeds via a clathrin-independent, caveolae-dependent entry pathway, allowing the internalised bacteria to survive within the cells. Intracellular bacteria were found inside non-acidic endosomes with high sphingomyelin and cholesterol content, or "free" in the cytosol of the invaded cells, suggesting that the ACT-induced bacterial uptake may not proceed through formation of late endolysosomes. Activation of Tyr kinases and toxin-induced Ca(2+)-influx are essential for the entry process. We hypothesize that B. pertussis might use ACT to activate the endocytic machinery of non-phagocytic cells and gain entry into these cells, in this way evading the host immune system.

  12. Activation of peroxisome proliferator-activated receptors (PPARs) by their ligands and protein kinase A activators

    Science.gov (United States)

    Lazennec, Gwendal; Canaple, Laurence; Saugy, Damien; Wahli, Walter

    2000-01-01

    The nuclear peroxisome proliferator-activated receptors (PPARs) α, β and γ activate the transcription of multiple genes involved in lipid metabolism. Several natural and synthetic ligands have been identified for each PPAR isotype but little is known about the phosphorylation state of these receptors. We show here that activators of protein kinase A (PKA) can enhance mouse PPAR activity in the absence and the presence of exogenous ligands in transient transfection experiments. The activation function 1 (AF-1) of PPARs was dispensable for transcriptional enhancement, whereas the activation function 2 (AF-2) was required for this effect. We also show that several domains of PPAR can be phosphorylated by PKA in vitro. Moreover, gel experiments suggest that PKA stabilizes binding of the liganded PPAR to DNA. PKA inhibitors decreased not only the kinase dependent induction of PPARs but also their ligand-dependent induction, suggesting that the ligands may also mobilize the PKA pathway to lead to maximal transcriptional induction by PPARs. Moreover, comparing PPARα KO with PPARα wild-type mice, we show that the expression of the ACO gene can be regulated by PKA-activated PPARα in liver. These data demonstrate that the PKA pathway is an important modulator of PPAR activity and we propose a model associating this pathway in the control of fatty acid β-oxidation under conditions of fasting, stress and exercise. PMID:11117527

  13. The role and regulation of the peroxisome proliferator activated receptor alpha in human liver

    NARCIS (Netherlands)

    Kersten, Sander; Stienstra, Rinke

    2017-01-01

    The peroxisome proliferator-activated receptor α (PPARα) is a ligand-activated transcription factor that is abundantly expressed in liver. PPARα is activated by fatty acids and various other lipid species, as well as by a class of chemicals referred to as peroxisome proliferators. Studies in mice

  14. Peroxisome Proliferator-Activated Receptor-γ in Thyroid Autoimmunity

    Directory of Open Access Journals (Sweden)

    Silvia Martina Ferrari

    2015-01-01

    Full Text Available Peroxisome proliferator-activated receptor- (PPAR- γ expression has been shown in thyroid tissue from patients with thyroiditis or Graves’ disease and furthermore in the orbital tissue of patients with Graves’ ophthalmopathy (GO, such as in extraocular muscle cells. An increasing body of evidence shows the importance of the (C-X-C motif receptor 3 (CXCR3 and cognate chemokines (C-X-C motif ligand (CXCL9, CXCL10, and CXCL11, in the T helper 1 immune response and in inflammatory diseases such as thyroid autoimmune disorders. PPAR-γ agonists show a strong inhibitory effect on the expression and release of CXCR3 chemokines, in vitro, in various kinds of cells, such as thyrocytes, and in orbital fibroblasts, preadipocytes, and myoblasts from patients with GO. Recently, it has been demonstrated that rosiglitazone is involved in a higher risk of heart failure, stroke, and all-cause mortality in old patients. On the contrary, pioglitazone has not shown these effects until now; this favors pioglitazone for a possible use in patients with thyroid autoimmunity. However, further studies are ongoing to explore the use of new PPAR-γ agonists in the treatment of thyroid autoimmune disorders.

  15. Acute myeloid leukemia associated with t(10;17)(p13-15;q12-21) and phagocytic activity by leukemic blasts: a clinical study and review of the literature.

    Science.gov (United States)

    Oh, Seung Hwan; Park, Tae Sung; Cho, Sun Young; Kim, Min Jin; Huh, Jungwon; Kim, Bomi; Song, Sae Am; Lee, Ja Young; Jun, Kyung Ran; Shin, Jeong Hwan; Kim, Hye Ran; Lee, Jeong Nyeo

    2010-10-01

    Translocation (10;17)(p13-15;q12-21) in acute leukemia is rarely reported in the literature. Here, we present both a novel t(10;17) case study and a review of relevant literature on t(10;17) in acute leukemia (10 cases). In summary, we came to the following preliminary conclusions: t(10;17) is associated with poorly differentiated acute leukemia subtype [90%; eight cases of acute myeloid leukemia (AML M0, M1) and one case of acute undifferentiated leukemia], phagocytic activity by blasts occurs (30%), and the survival time was short in three of the seven t(10;17) cases for whom follow-up data were available (median, 8 months). More clinical studies concerning the prognosis, treatment response, and survival of patients with t(10;17) are necessary. 2010 Elsevier Inc. All rights reserved.

  16. Similarities and differences between the responses induced in human phagocytes through activation of the medium chain fatty acid receptor GPR84 and the short chain fatty acid receptor FFA2R.

    Science.gov (United States)

    Sundqvist, Martina; Christenson, Karin; Holdfeldt, André; Gabl, Michael; Mårtensson, Jonas; Björkman, Lena; Dieckmann, Regis; Dahlgren, Claes; Forsman, Huamei

    2018-05-01

    GPR84 is a recently de-orphanized member of the G-protein coupled receptor (GPCR) family recognizing medium chain fatty acids, and has been suggested to play important roles in inflammation. Due to the lack of potent and selective GPR84 ligands, the basic knowledge related to GPR84 functions is very limited. In this study, we have characterized the GPR84 activation profile and regulation mechanism in human phagocytes, using two recently developed small molecules that specifically target GPR84 agonistically (ZQ16) and antagonistically (GLPG1205), respectively. Compared to our earlier characterization of the short chain fatty acid receptor FFA2R which is functionally expressed in neutrophils but not in monocytes, GPR84 is expressed in both cell types and in monocyte-derived macrophages. In neutrophils, the GPR84 agonist had an activation profile very similar to that of FFA2R. The GPR84-mediated superoxide release was low in naïve cells, but the response could be significantly primed by TNFα and by the actin cytoskeleton disrupting agent Latrunculin A. Similar to that of FFA2R, a desensitization mechanism bypassing the actin cytoskeleton was utilized by GPR84. All ZQ16-mediated cellular responses were sensitive to GLPG1205, confirming the GPR84-dependency. Finally, our data of in vivo transmigrated tissue neutrophils indicate that both GPR84 and FFA2R are involved in neutrophil recruitment processes in vivo. In summary, we show functional similarities but also some important differences between GPR84 and FFA2R in human phagocytes, thus providing some mechanistic insights into GPR84 regulation in blood neutrophils and cells recruited to an aseptic inflammatory site in vivo. Copyright © 2018 Elsevier B.V. All rights reserved.

  17. Topical Rosiglitazone Treatment Improves Ulcerative Colitis by Restoring Peroxisome Proliferator-Activated Receptor-gamma Activity

    DEFF Research Database (Denmark)

    Pedersen, G.; Brynskov, Jørn

    2010-01-01

    OBJECTIVES: Impaired epithelial expression of peroxisome proliferator-activated receptor-gamma (PPAR gamma) has been described in animal colitis models and briefly in patients with ulcerative colitis, but the functional significance in humans is not well defined. We examined PPAR gamma expression...

  18. Hepatocellular proliferation in response to agonists of peroxisome proliferator-activated receptor alpha: a role for kupffer cells?

    Directory of Open Access Journals (Sweden)

    Cunningham Michael

    2006-01-01

    Full Text Available Abstract Background It has been proposed that PPARα agonists stimulate Kupffer cells in rodents which in turn, release mitogenic factors leading to hepatic hyperplasia, and eventually cancer. However, Kupffer cells do not express PPARα receptors, and PPARα agonists stimulate hepatocellular proliferation in both TNFα- and TNFα receptor-null mice, casting doubt on the involvement of Kupffer cells in the mitogenic response to PPARα agonists. This study was therefore designed to investigate whether the PPARα agonist PFOA and the Kupffer cell inhibitor methylpalmitate produce opposing effects on hepatocellular proliferation and Kupffer cell activity in vivo, in a manner that would implicate these cells in the mitogenic effects of PPARα agonists. Methods Male Sprague-Dawley rats were treated intravenously via the tail vein with methylpalmitate 24 hrs prior to perfluorooctanoic acid (PFOA, and were sacrificed 24 hrs later, one hr after an intraperitoneal injection of bromodeoxyuridine (BrdU. Sera were analyzed for TNFα and IL-1β. Liver sections were stained immunohistochemically and quantified for BrdU incorporated into DNA. Results Data show that PFOA remarkably stimulated hepatocellular proliferation in the absence of significant changes in the serum levels of either TNFα or IL-1β. In addition, methylpalmitate did not alter the levels of these mitogens in PFOA-treated animals, despite the fact that it significantly blocked the hepatocellular proliferative effect of PFOA. Correlation between hepatocellular proliferation and serum levels of TNFα or IL-1β was extremely poor. Conclusion It is unlikely that mechanisms involving Kupffer cells play an eminent role in the hepatic hyperplasia, and consequently hepatocarcinogenicity attributed to PPARα agonists. This conclusion is based on the above mentioned published data and the current findings showing animals treated with PFOA alone or in combination with methylpalmitate to have similar

  19. In vitro exposure of haemocytes of the clam Ruditapes philippinarum to titanium dioxide (TiO2) nanoparticles: nanoparticle characterisation, effects on phagocytic activity and internalisation of nanoparticles into haemocytes.

    Science.gov (United States)

    Marisa, Ilaria; Marin, Maria Gabriella; Caicci, Federico; Franceschinis, Erica; Martucci, Alessandro; Matozzo, Valerio

    2015-02-01

    The continuous growth of nanotechnology and nano-industries, the considerable increase of products containing nanoparticles (NPs) and the potential release of NPs in aquatic environments suggest a need to study NP effects on aquatic organisms. In this context, in vitro assays are commonly used for evaluating or predicting the negative effects of chemicals and for understanding their mechanisms of action. In this study, a physico-chemical characterisation of titanium dioxide NPs (n-TiO2) was performed, and an in vitro approach was used to investigate the effects of n-TiO2 on haemocytes of the clam Ruditapes philippinarum. In particular, the effects on haemocyte phagocytic activity were evaluated in two different experiments (with and without pre-treatment of haemocytes) by exposing cells to P25 n-TiO2 (0, 1 and 10 μg/mL). In addition, the capability of n-TiO2 to interact with clam haemocytes was evaluated with a transmission electron microscope (TEM). In this study, n-TiO2 particles showed a mean diameter of approximately 21 nm, and both anatase (70%) and rutile (30%) phases were revealed. In both experiments, n-TiO2 significantly decreased the phagocytic index compared with the control, suggesting that NPs are able to interfere with cell functions. The results of the TEM analysis support this hypothesis. Indeed, we observed that TiO2 NPs interact with cell membranes and enter haemocyte cytoplasm and vacuoles after 60 min of exposure. To the best of our knowledge, this is the first study demonstrating the internalisation of TiO2 NPs into R. philippinarum haemocytes. The present study can contribute to the understanding of the mechanisms of action of TiO2 NPs in bivalve molluscs, at least at the haemocyte level. Copyright © 2014 Elsevier Ltd. All rights reserved.

  20. Inhibitory effect of immature dendritic cells (iDCs phagocytizing apoptotic lymphocytes on LPS-mediated activation of iDCs

    Directory of Open Access Journals (Sweden)

    Yu-xiang WEI

    2013-09-01

    Full Text Available Objective To investigate the inhibitory effect of immature dendritic cells(iDCs on LPS-mediated maturation of iDCs phagocytizing allogeneic spleen lymphocytes after being treated bypsoralen plus ultraviolet A(PUVA. Methods Bone marrow-derived DCs were obtained from bone marrow cells of C57BL/6 mice by co-cultivation with recombinant mouse IL-4 and GM-CSF. Spleenlymphocytes(SLP of BALB/c mice were isolated and transformed to PUVA-SLP by treatment with 8-methoxy PUVA irradiation.The bone marrow-derived iDCs of C57BL/6 were co-cultured with PUVA-SLP of BALB/c mice to obtain PUVA¬SLPDCs. After incubation, iDCs and PUVA-SP DCs were induced to maturation by LPS(10ng/ml,24h, and then they were analyzed by flow cytometry.At the same time,the concentrations of the immunoreactive proteins IL-12p70,IL-12p40andIL-10 in cell supernatants were determined by ELISA kits according to the manufacturer's recommendations. Results PUVA-SLP DCs and iDCs were compared in terms of LPS responsiveness.The phenotype of iDCs(CD40,CD80, andCD86 was 50.58%, 66.29%, 71.20%, respectively, showed more rapid changes from immature to mature statein response to LPS stimulation compared with PUVA-SP DCs, the phenotype of which was 21.26%,38.50% and 39.78%, respectively(P0.05.PUVA-SPDCs secreted high levels of IL-10(435.6±13.9, but lowlevels of IL-12(p7018.56±1.3,p4015.22±1.2, as compared with those of iDCs (132.6±2.8, p70192.1±5.9, p40999.8±26.9, P<0.01 after LPS stimulation. Conclusions Although PUVA-SLPDCs do not express as immature phenotype, they can be readily induced to differentiate into mature DCs in the presence of antigen or LPS. It may be suitable to use iDCs clinically in autoimmune diseases and transplantation.

  1. Effects of Enrofloxacin on Porcine Phagocytic Function

    OpenAIRE

    Schoevers, E. J.; van Leengoed, L. A. M. G.; Verheijden, J. H. M.; Niewold, T. A.

    1999-01-01

    The interaction between enrofloxacin and porcine phagocytes was studied with clinically relevant concentrations of enrofloxacin. Enrofloxacin accumulated in phagocytes, with cellular concentration/extracellular concentration ratios of 9 for polymorphonuclear leukocytes (PMNs) and 5 for alveolar macrophages (AMs). Cells with accumulated enrofloxacin brought into enrofloxacin-free medium released approximately 80% (AMs) to 90% (PMNs) of their enrofloxacin within the first 10 min, after which no...

  2. Structure-activity relationships of rosiglitazone for peroxisome proliferator-activated receptor gamma transrepression.

    Science.gov (United States)

    Toyota, Yosuke; Nomura, Sayaka; Makishima, Makoto; Hashimoto, Yuichi; Ishikawa, Minoru

    2017-06-15

    Anti-inflammatory effects of peroxisome proliferator-activated receptor gamma (PPRAγ) ligands are thought to be largely due to PPARγ-mediated transrepression. Thus, transrepression-selective PPARγ ligands without agonistic activity or with only partial agonistic activity should exhibit anti-inflammatory properties with reduced side effects. Here, we investigated the structure-activity relationships (SARs) of PPARγ agonist rosiglitazone, focusing on transrepression activity. Alkenic analogs showed slightly more potent transrepression with reduced efficacy of transactivating agonistic activity. Removal of the alkyl group on the nitrogen atom improved selectivity for transrepression over transactivation. Among the synthesized compounds, 3l exhibited stronger transrepressional activity (IC 50 : 14μM) and weaker agonistic efficacy (11%) than rosiglitazone or pioglitazone. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Tetraspanin CD9 modulates human lymphoma cellular proliferation via histone deacetylase activity

    Energy Technology Data Exchange (ETDEWEB)

    Herr, Michael J. [Vascular Biology Center of Excellence, The University of Tennessee Health Science Center, Memphis, TN 38163 (United States); Department of Medicine, The University of Tennessee Health Science Center, Memphis, TN 38163 (United States); Department of Molecular Sciences, The University of Tennessee Health Science Center, Memphis, TN 38163 (United States); Department of Surgery, The University of Tennessee Health Science Center, Memphis, TN 38163 (United States); Longhurst, Celia M.; Baker, Benjamin [Vascular Biology Center of Excellence, The University of Tennessee Health Science Center, Memphis, TN 38163 (United States); Homayouni, Ramin [Department of Biology, Bioinformatics Program, University of Memphis, Memphis, TN 38152 (United States); Speich, Henry E.; Kotha, Jayaprakash [Vascular Biology Center of Excellence, The University of Tennessee Health Science Center, Memphis, TN 38163 (United States); Jennings, Lisa K., E-mail: ljennings@uthsc.edu [Vascular Biology Center of Excellence, The University of Tennessee Health Science Center, Memphis, TN 38163 (United States); Department of Medicine, The University of Tennessee Health Science Center, Memphis, TN 38163 (United States); Department of Molecular Sciences, The University of Tennessee Health Science Center, Memphis, TN 38163 (United States); Department of Surgery, The University of Tennessee Health Science Center, Memphis, TN 38163 (United States); Department of Biology, Bioinformatics Program, University of Memphis, Memphis, TN 38152 (United States)

    2014-05-16

    Highlights: • CD9 is differentially expressed in human Burkitt’s lymphoma cells. • We found that CD9 expression promotes these cells proliferation. • CD9 expression also increases HDAC activity. • HDAC inhibition decreased both cell proliferation and importantly CD9 expression. • CD9 may dictate HDAC efficacy and play a role in HDAC regulation. - Abstract: Non-Hodgkin Lymphoma (NHL) is a type of hematological malignancy that affects two percent of the overall population in the United States. Tetraspanin CD9 is a cell surface protein that has been thoroughly demonstrated to be a molecular facilitator of cellular phenotype. CD9 expression varies in two human lymphoma cell lines, Raji and BJAB. In this report, we investigated the functional relationship between CD9 and cell proliferation regulated by histone deacetylase (HDAC) activity in these two cell lines. Introduction of CD9 expression in Raji cells resulted in significantly increased cell proliferation and HDAC activity compared to Mock transfected Raji cells. The increase in CD9–Raji cell proliferation was significantly inhibited by HDAC inhibitor (HDACi) treatment. Pretreatment of BJAB cells with HDAC inhibitors resulted in a significant decrease in endogenous CD9 mRNA and cell surface expression. BJAB cells also displayed decreased cell proliferation after HDACi treatment. These results suggest a significant relationship between CD9 expression and cell proliferation in human lymphoma cells that may be modulated by HDAC activity.

  4. Report on Activities and Programs for Countering Proliferation and NBC Terrorism. Volume 1. Executive Summary

    National Research Council Canada - National Science Library

    2006-01-01

    This Report on Activities and Programs for Countering Proliferation and NBC Terrorism is submitted to the United States Congress as required by the 1994 National Defense Authorization Act (NDAA) (as amended...

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

    International Nuclear Information System (INIS)

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

    2009-01-01

    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 2 (PGE 2 ) in the proliferation of astrocytes. The proliferation of astrocytes was measured by BrdU incorporation. The level of PGE 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 2 in enhanced astrocyte proliferation was suggested by the findings that PGE 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 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 2 to the media significantly induced astrocyte proliferation. These results indicate that microglial PGE 2 plays an important role in astrocyte proliferation, identifying PGE 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 2 in astrocyte proliferation and in suggesting a potential avenue in the use of anti-inflammatory agents for the therapy of astroglioma.

  6. Activation and Molecular Targets of Peroxisome Proliferator-Activated Receptor-γ Ligands in Lung Cancer

    Directory of Open Access Journals (Sweden)

    Raphael A. Nemenoff

    2008-01-01

    Full Text Available Lung cancer is the leading cause of cancer death, and five-year survival remains poor, raising the urgency for new treatment strategies. Activation of PPARγ represents a potential target for both the treatment and prevention of lung cancer. Numerous studies have examined the effect of thiazolidinediones such as rosiglitazone and pioglitazone on lung cancer cells in vitro and in xenograft models. These studies indicate that activation of PPARγ inhibits cancer cell proliferation as well as invasiveness and metastasis. While activation of PPARγ can occur by direct binding of pharmacological ligands to the molecule, emerging data indicate that PPARγ activation can occur through engagement of other signal transduction pathways, including Wnt signaling and prostaglandin production. Data, both from preclinical models and retrospective clinical studies, indicate that activation of PPARγ may represent an attractive chemopreventive strategy. This article reviews the existing biological and mechanistic experiments focusing on the role of PPARγ in lung cancer, focusing specifically on nonsmall cell lung cancer.

  7. Proliferation activity and radiosensitivity of CFU-S in their decreased compartments in continuously irradiated rats

    International Nuclear Information System (INIS)

    Kalina, I.; Vacek, A.; Brezani, P.

    1984-01-01

    Effects of the continuous irradiation (0.25 Gy/day) on proliferation activity and radiosensitivity (D 0 ) of CFU-S were studied in rats after accumulated doses of 1.75 Gy and 15 Gy, resp. The proliferation activity of CFU-S in continuously irradiated groups was increased 4 - 5 fold compared with the control group. D 0 values for CFU-S in their decreased compartments were not changed after long-term irradiation compared with the controls. (author)

  8. The adipogenic acetyltransferase Tip60 targets activation function 1 of peroxisome proliferator-activated receptor gamma

    DEFF Research Database (Denmark)

    van Beekum, Olivier; Brenkman, Arjan B; Grøntved, Lars

    2008-01-01

    The transcription factor peroxisome proliferator-activated receptor gamma (PPARgamma) plays a key role in the regulation of lipid and glucose metabolism in adipocytes, by regulating their differentiation, maintenance, and function. The transcriptional activity of PPARgamma is dictated by the set...... in cells, and through use of chimeric proteins, we established that coactivation by Tip60 critically depends on the N-terminal activation function 1 of PPARgamma, a domain involved in isotype-specific gene expression and adipogenesis. Chromatin immunoprecipitation experiments showed that the endogenous Tip...... of proteins with which this nuclear receptor interacts under specific conditions. Here we identify the HIV-1 Tat-interacting protein 60 (Tip60) as a novel positive regulator of PPARgamma transcriptional activity. Using tandem mass spectrometry, we found that PPARgamma and the acetyltransferase Tip60 interact...

  9. Comparative anatomy of phagocytic and immunological synapses

    Directory of Open Access Journals (Sweden)

    Florence eNiedergang

    2016-01-01

    Full Text Available The generation of phagocytic cups and immunological synapses are crucial events of the innate and adaptive immune responses, respectively. They are triggered by distinct immune receptors and performed by different cell types. However, growing experimental evidence shows that a very close series of molecular and cellular events control these two processes. Thus, the tight and dynamic interplay between receptor signaling, actin and microtubule cytoskeleton, and targeted vesicle traffic are all critical features to build functional phagosomes and immunological synapses. Interestingly, both phagocytic cups and immunological synapses display particular spatial and temporal patterns of receptors and signaling molecules, leading to the notion of phagocytic synapse. Here we discuss both types of structures, their organization and the mechanisms by which they are generated and regulated.

  10. Atlas of peaceful and military nuclear activities (from origins to proliferation)

    International Nuclear Information System (INIS)

    Chaliand, G.; Jan, M.

    1993-01-01

    This atlas collects worldwide geopolitical data and maps concerning peaceful and military activities. It is made of six parts: (1) origins (history); (2) strategies; (3) nuclear fuel cycle; (4) peaceful activities; (5) military activities; (6) proliferation. (D.L.). figs., maps

  11. Modulating Estrogen Receptor-related Receptor-α Activity Inhibits Cell Proliferation*

    OpenAIRE

    Bianco, Stéphanie; Lanvin, Olivia; Tribollet, Violaine; Macari, Claire; North, Sophie; Vanacker, Jean-Marc

    2009-01-01

    High expression of the estrogen receptor-related receptor (ERR)-α in human tumors is correlated to a poor prognosis, suggesting an involvement of the receptor in cell proliferation. In this study, we show that a synthetic compound (XCT790) that modulates the activity of ERRα reduces the proliferation of various cell lines and blocks the G1/S transition of the cell cycle in an ERR...

  12. Surface modification of nanoparticles enables selective evasion of phagocytic clearance by distinct macrophage phenotypes

    Science.gov (United States)

    Qie, Yaqing; Yuan, Hengfeng; von Roemeling, Christina A.; Chen, Yuanxin; Liu, Xiujie; Shih, Kevin D.; Knight, Joshua A.; Tun, Han W.; Wharen, Robert E.; Jiang, Wen; Kim, Betty Y. S.

    2016-05-01

    Nanomedicine is a burgeoning industry but an understanding of the interaction of nanomaterials with the immune system is critical for clinical translation. Macrophages play a fundamental role in the immune system by engulfing foreign particulates such as nanoparticles. When activated, macrophages form distinct phenotypic populations with unique immune functions, however the mechanism by which these polarized macrophages react to nanoparticles is unclear. Furthermore, strategies to selectively evade activated macrophage subpopulations are lacking. Here we demonstrate that stimulated macrophages possess higher phagocytic activities and that classically activated (M1) macrophages exhibit greater phagocytic capacity than alternatively activated (M2) macrophages. We show that modification of nanoparticles with polyethylene-glycol results in decreased clearance by all macrophage phenotypes, but importantly, coating nanoparticles with CD47 preferentially lowers phagocytic activity by the M1 phenotype. These results suggest that bio-inspired nanoparticle surface design may enable evasion of specific components of the immune system and provide a rational approach for developing immune tolerant nanomedicines.

  13. Activated Rac1 requires gp130 for Stat3 activation, cell proliferation and migration

    Energy Technology Data Exchange (ETDEWEB)

    Arulanandam, Rozanne; Geletu, Mulu [Departments of Microbiology and Immunology and Pathology and Molecular Medicine, and Queen' s University Cancer Institute, Queen' s University, Botterell Hall, Rm. 713, Kingston, Ontario, Canada K7L 3N6 (Canada); Feracci, Helene [Universite Bordeaux 1, Centre de Recherche Paul Pascal, CNRS UPR 8641, 33600 Pessac (France); Raptis, Leda, E-mail: raptisl@queensu.ca [Departments of Microbiology and Immunology and Pathology and Molecular Medicine, and Queen' s University Cancer Institute, Queen' s University, Botterell Hall, Rm. 713, Kingston, Ontario, Canada K7L 3N6 (Canada)

    2010-03-10

    Rac1 (Rac) is a member of the Rho family of small GTPases which controls cell migration by regulating the organization of actin filaments. Previous results suggested that mutationally activated forms of the Rho GTPases can activate the Signal Transducer and Activator of Transcription-3 (Stat3), but the exact mechanism is a matter of controversy. We recently demonstrated that Stat3 activity of cultured cells increases dramatically following E-cadherin engagement. To better understand this pathway, we now compared Stat3 activity levels in mouse HC11 cells before and after expression of the mutationally activated Rac1 (Rac{sup V12}), at different cell densities. The results revealed for the first time a dramatic increase in protein levels and activity of both the endogenous Rac and Rac{sup V12} with cell density, which was due to inhibition of proteasomal degradation. In addition, Rac{sup V12}-expressing cells had higher Stat3, tyrosine-705 phosphorylation and activity levels at all densities, indicating that Rac{sup V12} is able to activate Stat3. Further examination of the mechanism of Stat3 activation showed that Rac{sup V12} expression caused a surge in mRNA of Interleukin-6 (IL6) family cytokines, known potent Stat3 activators. Knockdown of gp130, the common subunit of this family reduced Stat3 activity, indicating that these cytokines may be responsible for the Stat3 activation by Rac{sup V12}. The upregulation of IL6 family cytokines was required for cell migration and proliferation induced by Rac{sup V12}, as shown by gp130 knockdown experiments, thus demonstrating that the gp130/Stat3 axis represents an essential effector of activated Rac for the regulation of key cellular functions.

  14. Activated Rac1 requires gp130 for Stat3 activation, cell proliferation and migration

    International Nuclear Information System (INIS)

    Arulanandam, Rozanne; Geletu, Mulu; Feracci, Helene; Raptis, Leda

    2010-01-01

    Rac1 (Rac) is a member of the Rho family of small GTPases which controls cell migration by regulating the organization of actin filaments. Previous results suggested that mutationally activated forms of the Rho GTPases can activate the Signal Transducer and Activator of Transcription-3 (Stat3), but the exact mechanism is a matter of controversy. We recently demonstrated that Stat3 activity of cultured cells increases dramatically following E-cadherin engagement. To better understand this pathway, we now compared Stat3 activity levels in mouse HC11 cells before and after expression of the mutationally activated Rac1 (Rac V12 ), at different cell densities. The results revealed for the first time a dramatic increase in protein levels and activity of both the endogenous Rac and Rac V12 with cell density, which was due to inhibition of proteasomal degradation. In addition, Rac V12 -expressing cells had higher Stat3, tyrosine-705 phosphorylation and activity levels at all densities, indicating that Rac V12 is able to activate Stat3. Further examination of the mechanism of Stat3 activation showed that Rac V12 expression caused a surge in mRNA of Interleukin-6 (IL6) family cytokines, known potent Stat3 activators. Knockdown of gp130, the common subunit of this family reduced Stat3 activity, indicating that these cytokines may be responsible for the Stat3 activation by Rac V12 . The upregulation of IL6 family cytokines was required for cell migration and proliferation induced by Rac V12 , as shown by gp130 knockdown experiments, thus demonstrating that the gp130/Stat3 axis represents an essential effector of activated Rac for the regulation of key cellular functions.

  15. Activation of peroxisome proliferator-activated receptor-α enhances fatty acid oxidation in human adipocytes

    International Nuclear Information System (INIS)

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

    2011-01-01

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

  16. Cell proliferation is a key determinant of the outcome of FOXO3a activation

    Energy Technology Data Exchange (ETDEWEB)

    Poulsen, Raewyn C., E-mail: raewyn.poulsen@gmail.com; Carr, Andrew J.; Hulley, Philippa A.

    2015-06-19

    The FOXO family of forkhead transcription factors have a pivotal role in determining cell fate in response to oxidative stress. FOXO activity can either promote cell survival or induce cell death. Increased FOXO-mediated cell death has been implicated in the pathogenesis of degenerative diseases affecting musculoskeletal tissues. The aim of this study was to determine the conditions under which one member of the FOXO family, FOXO3a, promotes cell survival as opposed to cell death. Treatment of primary human tenocytes with 1 pM hydrogen peroxide for 18 h resulted in increased protein levels of FOXO3a. In peroxide-treated cells cultured in low serum media, FOXO3a inhibited cell proliferation and protected against apoptosis. However in peroxide treated cells cultured in high serum media, cell proliferation was unchanged but level of apoptosis significantly increased. Similarly, in tenocytes transduced to over-express FOXO3a, cell proliferation was inhibited and level of apoptosis unchanged in cells cultured in low serum. However there was a robust increase in cell death in FOXO3a-expressing cells cultured in high serum. Inhibition of cell proliferation in either peroxide-treated or FOXO3a-expressing cells cultured in high serum protected against apoptosis induction. Conversely, addition of a Chk2 inhibitor to peroxide-treated or FOXO3a-expressing cells overrode the inhibitory effect of FOXO3a on cell proliferation and led to increased apoptosis in cells cultured in low serum. This study demonstrates that proliferating cells may be particularly susceptible to the apoptosis-inducing actions of FOXO3a. Inhibition of cell proliferation by FOXO3a may be a critical event in allowing the pro-survival rather than the pro-apoptotic activity of FOXO3a to prevail. - Highlights: • FOXO3a activity can result in either promotion of cell survival or apoptosis. • The outcome of FOXO3a activation differs in proliferating compared to non-proliferating cells. • Proliferating

  17. Cell proliferation is a key determinant of the outcome of FOXO3a activation

    International Nuclear Information System (INIS)

    Poulsen, Raewyn C.; Carr, Andrew J.; Hulley, Philippa A.

    2015-01-01

    The FOXO family of forkhead transcription factors have a pivotal role in determining cell fate in response to oxidative stress. FOXO activity can either promote cell survival or induce cell death. Increased FOXO-mediated cell death has been implicated in the pathogenesis of degenerative diseases affecting musculoskeletal tissues. The aim of this study was to determine the conditions under which one member of the FOXO family, FOXO3a, promotes cell survival as opposed to cell death. Treatment of primary human tenocytes with 1 pM hydrogen peroxide for 18 h resulted in increased protein levels of FOXO3a. In peroxide-treated cells cultured in low serum media, FOXO3a inhibited cell proliferation and protected against apoptosis. However in peroxide treated cells cultured in high serum media, cell proliferation was unchanged but level of apoptosis significantly increased. Similarly, in tenocytes transduced to over-express FOXO3a, cell proliferation was inhibited and level of apoptosis unchanged in cells cultured in low serum. However there was a robust increase in cell death in FOXO3a-expressing cells cultured in high serum. Inhibition of cell proliferation in either peroxide-treated or FOXO3a-expressing cells cultured in high serum protected against apoptosis induction. Conversely, addition of a Chk2 inhibitor to peroxide-treated or FOXO3a-expressing cells overrode the inhibitory effect of FOXO3a on cell proliferation and led to increased apoptosis in cells cultured in low serum. This study demonstrates that proliferating cells may be particularly susceptible to the apoptosis-inducing actions of FOXO3a. Inhibition of cell proliferation by FOXO3a may be a critical event in allowing the pro-survival rather than the pro-apoptotic activity of FOXO3a to prevail. - Highlights: • FOXO3a activity can result in either promotion of cell survival or apoptosis. • The outcome of FOXO3a activation differs in proliferating compared to non-proliferating cells. • Proliferating

  18. Peroxisome Proliferator-Activated Receptor Ligands and Their Role in Chronic Myeloid Leukemia: Therapeutic Strategies.

    Science.gov (United States)

    Yousefi, Bahman; Samadi, Nasser; Baradaran, Behzad; Shafiei-Irannejad, Vahid; Zarghami, Nosratollah

    2016-07-01

    Imatinib therapy remains the gold standard for treatment of chronic myeloid leukemia; however, the acquired resistance to this therapeutic agent in patients has urged the scientists to devise modalities for overcoming this chemoresistance. For this purpose, initially therapeutic agents with higher tyrosine kinase activity were introduced, which had the potential for inhibiting even mutant forms of Bcr-Abl. Furthermore, coupling imatinib with peroxisome proliferator-activated receptor ligands also showed beneficial effects in chronic myeloid leukemia cell proliferation. These combination protocols inhibited cell growth and induced apoptosis as well as differentiation in chronic myeloid leukemia cell lines. In addition, peroxisome proliferator-activated receptors ligands increased imatinib uptake by upregulating the expression of human organic cation transporter 1. Taken together, peroxisome proliferator-activated receptors ligands are currently being considered as novel promising therapeutic candidates for chronic myeloid leukemia treatment, because they can synergistically enhance the efficacy of imatinib. In this article, we reviewed the potential of peroxisome proliferator-activated receptors ligands for use in chronic myeloid leukemia treatment. The mechanism of action of these therapeutics modalities are also presented in detail. © 2016 John Wiley & Sons A/S.

  19. New trends of activity on supporting of non-proliferation regime

    International Nuclear Information System (INIS)

    Issaeva, G.M.; Tyupkina, O.G.

    2002-01-01

    Taking into account the necessity of all possible strengthening of non-proliferation regimes Kazakhstan participates in a number of agreements and associations: Nuclear Non-proliferation Treaty, Comprehensive Test-Ban-Treaty, International Atomic Energy Agency, Nuclear Supplier Group, Missile Technology Control Regime, Conference on Disarmament, etc. The Cooperative Threat Reduction Program (CTR) greatly influenced on the development on non-proliferation regime in Kazakhstan. During initial stage of CTR activity (1993-1995) military projects prevailed. Later (1995-1997) the projects on liquidation of infrastructure for nuclear and bio- weapons were successfully realized. Last years, since 1999, the attention was shifted towards proliferation prevention of hazardous nuclear and biological materials. Recent terrorist acts and world community activity on global safety strengthening underline an urgency of quite new problems that entirely applied to Kazakhstan: monitoring of hazardous materials; enhancement of safety systems of 'risky' facilities and technologies; creation and/or upgrading of safety systems for industry infrastructure. The proposals of these new trends of non-proliferation have been developed. Development of physical protection system for oil and gas industry infrastructure of Kazakhstan based on safety concepts of nuclear facilities; Evaluation of radionuclide contamination and safety of oil and gas facilities of the Caspian region; Counteraction to nuclear materials proliferation; Cooperative approaches in preventing/reducing of illicit trafficking and use of WMD-related explosive materials. Implementation of the project would make of substantial contribution to successful solution of either regional or global safety problem

  20. The X protein of hepatitis B virus activates hepatoma cell proliferation through repressing melanoma inhibitory activity 2 gene

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Yilin; Yang, Yang; Cai, Yanyan; Liu, Fang; Liu, Yingle; Zhu, Ying [State Key Laboratory of Virology, College of Life Sciences, and Chinese-French Liver Disease Research Institute at Zhongnan Hospital, Wuhan University, Wuhan 430072 (China); Wu, Jianguo, E-mail: jwu@whu.edu.cn [State Key Laboratory of Virology, College of Life Sciences, and Chinese-French Liver Disease Research Institute at Zhongnan Hospital, Wuhan University, Wuhan 430072 (China)

    2011-12-16

    Highlights: Black-Right-Pointing-Pointer We demonstrated that HBV represses MIA2 gene expression both invitro and in vivo. Black-Right-Pointing-Pointer The X protein of HBV plays a major role in such regulation. Black-Right-Pointing-Pointer Knock-down of MIA2 in HepG2 cells activates cell growth and proliferation. Black-Right-Pointing-Pointer HBx activates cell proliferation, over-expression of MIA2 impaired such regulation. Black-Right-Pointing-Pointer HBx activates hepatoma cell proliferation through repressing MIA2 expression. -- Abstract: Hepatocellular carcinoma (HCC) is the fourth leading cause of cancer deaths globally. Chronic hepatitis B virus (HBV) infection accounts for over 75% of all HCC cases; however, the molecular pathogenesis of HCC is not well understood. In this study, we found that the expression of the newly identified gene melanoma inhibitory activity 2 (MIA2) was reduced by HBV infection invitro and invivo, and that HBV X protein (HBx) plays a major role in this regulation. Recent studies have revealed that MIA2 is a potential tumor suppressor, and that, in most HCCs, MIA2 expression is down-regulated or lost. We found that the knock-down of MIA2 in HepG2 cells activated cell growth and proliferation, suggesting that MIA2 inhibits HCC cell growth and proliferation. In addition, the over-expression of HBx alone induced cell proliferation, whereas MIA2 over-expression impaired the HBx-mediated induction of proliferation. Taken together, our results suggest that HBx activates hepatoma cell growth and proliferation through repression of the potential tumor suppressor MIA2.

  1. Inhibition of T cell proliferation by selective block of Ca(2+)-activated K(+) channels

    DEFF Research Database (Denmark)

    Jensen, B S; Odum, Niels; Jorgensen, N K

    1999-01-01

    cell activation and proliferation has been investigated by using various blockers of IK channels. The Ca(2+)-activated K(+) current in human T cells is shown by the whole-cell voltage-clamp technique to be highly sensitive to clotrimazole, charybdotoxin, and nitrendipine, but not to ketoconazole...

  2. Peroxisome proliferators-activated receptor (PPAR) regulation in cardiac metabolism and disease

    NARCIS (Netherlands)

    el Azzouzi, H.

    2009-01-01

    Peroxisome proliferators-activated receptors (PPARs) are members of the nuclear receptor family of ligand activated transcription factors and consist of the three isoforms, PPAR, PPAR/ and PPAR. Considerable evidence has established the importance of PPARs in myocardial lipid homeostasis and

  3. Activation of phagocytic cells by Staphylococcus epidermidis biofilms: effects of extracellular matrix proteins and the bacterial stress protein GroEL on netosis and MRP-14 release.

    Science.gov (United States)

    Dapunt, Ulrike; Gaida, Matthias M; Meyle, Eva; Prior, Birgit; Hänsch, Gertrud M

    2016-07-01

    The recognition and phagocytosis of free-swimming (planktonic) bacteria by polymorphonuclear neutrophils have been investigated in depth. However, less is known about the neutrophil response towards bacterial biofilms. Our previous work demonstrated that neutrophils recognize activating entities within the extracellular polymeric substance (EPS) of biofilms (the bacterial heat shock protein GroEL) and that this process does not require opsonization. Aim of this study was to evaluate the release of DNA by neutrophils in response to biofilms, as well as the release of the inflammatory cytokine MRP-14. Neutrophils were stimulated with Staphylococcus epidermidis biofilms, planktonic bacteria, extracted EPS and GroEL. Release of DNA and of MRP-14 was evaluated. Furthermore, tissue samples from patients suffering from biofilm infections were collected and evaluated by histology. MRP-14 concentration in blood samples was measured. We were able to show that biofilms, the EPS and GroEL induce DNA release. MRP-14 was only released after stimulation with EPS, not GroEL. Histology of tissue samples revealed MRP-14 positive cells in association with neutrophil infiltration and MRP-14 concentration was elevated in blood samples of patients suffering from biofilm infections. Our data demonstrate that neutrophil-activating entities are present in the EPS and that GroEL induces DNA release by neutrophils. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  4. Mechanisms Underlying the Delayed Activation of the Cap1 Transcription Factor in Candida albicans following Combinatorial Oxidative and Cationic Stress Important for Phagocytic Potency.

    Science.gov (United States)

    Kos, Iaroslava; Patterson, Miranda J; Znaidi, Sadri; Kaloriti, Despoina; da Silva Dantas, Alessandra; Herrero-de-Dios, Carmen M; d'Enfert, Christophe; Brown, Alistair J P; Quinn, Janet

    2016-03-29

    Following phagocytosis, microbes are exposed to an array of antimicrobial weapons that include reactive oxygen species (ROS) and cationic fluxes. This is significant as combinations of oxidative and cationic stresses are much more potent than the corresponding single stresses, triggering the synergistic killing of the fungal pathogenCandida albicansby "stress pathway interference." Previously we demonstrated that combinatorial oxidative plus cationic stress triggers a dramatic increase in intracellular ROS levels compared to oxidative stress alone. Here we show that activation of Cap1, the major regulator of antioxidant gene expression inC. albicans, is significantly delayed in response to combinatorial stress treatments and to high levels of H2O2 Cap1 is normally oxidized in response to H2O2; this masks the nuclear export sequence, resulting in the rapid nuclear accumulation of Cap1 and the induction of Cap1-dependent genes. Here we demonstrate that following exposure of cells to combinatorial stress or to high levels of H2O2, Cap1 becomes trapped in a partially oxidized form, Cap1(OX-1) Notably, Cap1-dependent gene expression is not induced when Cap1 is in this partially oxidized form. However, while Cap1(OX-1)readily accumulates in the nucleus and binds to target genes following high-H2O2stress, the nuclear accumulation of Cap1(OX-1)following combinatorial H2O2and NaCl stress is delayed due to a cationic stress-enhanced interaction with the Crm1 nuclear export factor. These findings define novel mechanisms that delay activation of the Cap1 transcription factor, thus preventing the rapid activation of the stress responses vital for the survival ofC. albicanswithin the host. Combinatorial stress-mediated synergistic killing represents a new unchartered area in the field of stress signaling. This phenomenon contrasts starkly with "stress cross-protection," where exposure to one stress protects against subsequent exposure to a different stress. Previously we

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

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Joo-Young; Hashizaki, Hikari; Goto, Tsuyoshi; Sakamoto, Tomoya; Takahashi, Nobuyuki [Laboratory of Molecular Function of Food, Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Uji, Kyoto 611-0011 (Japan); Kawada, Teruo, E-mail: fat@kais.kyoto-u.ac.jp [Laboratory of Molecular Function of Food, Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Uji, Kyoto 611-0011 (Japan)

    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

  6. Activation of a Neospora caninum EGFR-Like Kinase Facilitates Intracellular Parasite Proliferation

    Directory of Open Access Journals (Sweden)

    Xiaoxia Jin

    2017-10-01

    Full Text Available The Apicomplexan parasite Neospora caninum, an obligate intracellular protozoan, causes serious diseases in a number of mammalian species, especially in cattle. Infection with N. caninum is associated with abortions in both dairy and beef cattle worldwide which have a major economic impact on the cattle industry. However, the mechanism by which N. caninum proliferates within host cells is poorly understood. Epidermal growth factor receptor (EGFR is a protein kinase ubiquitously expressed, present on cell surfaces in numerous species, which has been confirmed to be essential in signal transduction involved in cell growth, proliferation, survival, and many other intracellular processes. However, the presence of EGFR in N. caninum and its role in N. caninum proliferation remain unclear. In the present study, we identified a putative EGFR-like kinase in N. caninum, which could be activated in tachyzoites by infection or treatment with rNcMIC3 [containing four epidermal growth factor (EGF domains] or human EGF. Blockade of EGFR-like in tachyzoites by AG1478 significantly reduced parasite proliferation in host cells. Our data suggested that the activation of tachyzoite EGFR-like might facilitate the intracellular proliferation of N. caninum.

  7. Perforin-2 is essential for intracellular defense of parenchymal cells and phagocytes against pathogenic bacteria

    Science.gov (United States)

    McCormack, Ryan M; de Armas, Lesley R; Shiratsuchi, Motoaki; Fiorentino, Desiree G; Olsson, Melissa L; Lichtenheld, Mathias G; Morales, Alejo; Lyapichev, Kirill; Gonzalez, Louis E; Strbo, Natasa; Sukumar, Neelima; Stojadinovic, Olivera; Plano, Gregory V; Munson, George P; Tomic-Canic, Marjana; Kirsner, Robert S; Russell, David G; Podack, Eckhard R

    2015-01-01

    Perforin-2 (MPEG1) is a pore-forming, antibacterial protein with broad-spectrum activity. Perforin-2 is expressed constitutively in phagocytes and inducibly in parenchymal, tissue-forming cells. In vitro, Perforin-2 prevents the intracellular replication and proliferation of bacterial pathogens in these cells. Perforin-2 knockout mice are unable to control the systemic dissemination of methicillin-resistant Staphylococcus aureus (MRSA) or Salmonella typhimurium and perish shortly after epicutaneous or orogastric infection respectively. In contrast, Perforin-2-sufficient littermates clear the infection. Perforin-2 is a transmembrane protein of cytosolic vesicles -derived from multiple organelles- that translocate to and fuse with bacterium containing vesicles. Subsequently, Perforin-2 polymerizes and forms large clusters of 100 Å pores in the bacterial surface with Perforin-2 cleavage products present in bacteria. Perforin-2 is also required for the bactericidal activity of reactive oxygen and nitrogen species and hydrolytic enzymes. Perforin-2 constitutes a novel and apparently essential bactericidal effector molecule of the innate immune system. DOI: http://dx.doi.org/10.7554/eLife.06508.001 PMID:26402460

  8. Diversity and functions of intestinal mononuclear phagocytes

    DEFF Research Database (Denmark)

    Joeris, Thorsten; Müller-Luda, K; Agace, William Winston

    2017-01-01

    The intestinal lamina propria (LP) contains a diverse array of mononuclear phagocyte (MNP) subsets, including conventional dendritic cells (cDC), monocytes and tissue-resident macrophages (mφ) that collectively play an essential role in mucosal homeostasis, infection and inflammation. In the curr......The intestinal lamina propria (LP) contains a diverse array of mononuclear phagocyte (MNP) subsets, including conventional dendritic cells (cDC), monocytes and tissue-resident macrophages (mφ) that collectively play an essential role in mucosal homeostasis, infection and inflammation....... In the current review we discuss the function of intestinal cDC and monocyte-derived MNP, highlighting how these subsets play several non-redundant roles in the regulation of intestinal immune responses. While much remains to be learnt, recent findings also underline how the various populations of MNP adapt...

  9. Peroxisome proliferator-activated receptor α activation induces hepatic steatosis, suggesting an adverse effect.

    Directory of Open Access Journals (Sweden)

    Fang Yan

    Full Text Available Non-alcoholic fatty liver disease (NAFLD is characterized by hepatic triglyceride accumulation, ranging from steatosis to steatohepatitis and cirrhosis. NAFLD is a risk factor for cardiovascular diseases and is associated with metabolic syndrome. Antihyperlipidemic drugs are recommended as part of the treatment for NAFLD patients. Although fibrates activate peroxisome proliferator-activated receptor α (PPARα, leading to the reduction of serum triglyceride levels, the effects of these drugs on NAFLD remain controversial. Clinical studies have reported that PPARα activation does not improve hepatic steatosis. In the present study, we focused on exploring the effect and mechanism of PPARα activation on hepatic triglyceride accumulation and hepatic steatosis. Male C57BL/6J mice, Pparα-null mice and HepG2 cells were treated with fenofibrate, one of the most commonly used fibrate drugs. Both low and high doses of fenofibrate were administered. Hepatic steatosis was detected through oil red O staining and electron microscopy. Notably, in fenofibrate-treated mice, the serum triglyceride levels were reduced and the hepatic triglyceride content was increased in a dose-dependent manner. Oil red O staining of liver sections demonstrated that fenofibrate-fed mice accumulated abundant neutral lipids. Fenofibrate also increased the intracellular triglyceride content in HepG2 cells. The expression of sterol regulatory element-binding protein 1c (SREBP-1c and the key genes associated with lipogenesis were increased in fenofibrate-treated mouse livers and HepG2 cells in a dose-dependent manner. However, the effect was strongly impaired in Pparα-null mice treated with fenofibrate. Fenofibrate treatment induced mature SREBP-1c expression via the direct binding of PPARα to the DR1 motif of the SREBP-1c gene. Taken together, these findings indicate the molecular mechanism by which PPARα activation increases liver triglyceride accumulation and suggest an

  10. Genomic organization of the mouse peroxisome proliferator-activated receptor beta/delta gene

    DEFF Research Database (Denmark)

    Larsen, Leif K; Amri, Ez-Zoubir; Mandrup, Susanne

    2002-01-01

    Peroxisome proliferator-activated receptor (PPAR) beta/delta is ubiquitously expressed, but the level of expression differs markedly between different cell types. In order to determine the molecular mechanisms governing PPARbeta/delta gene expression, we have isolated and characterized the mouse...

  11. Lysophosphatidic acid (LPA) effects on endometrial carcinoma in vitro proliferation, invasion, and matrix metalloproteinase activity.

    Science.gov (United States)

    Wang, Feng-qiang; Ariztia, Edgardo V; Boyd, Leslie R; Horton, Faith R; Smicun, Yoel; Hetherington, Jessica A; Smith, Phillip J; Fishman, David A

    2010-04-01

    Lysophosphatidic acid (LPA) has potent growth-regulatory effect in many cell types and has been linked to the in vivo tumor growth and metastasis in several malignancies. The goal of this study was to assess the regulation of (EC) microenvironment by LPA through the examination of its effect on cell proliferation, migration, invasion, uPA activity, and matrix metalloproteinase (MMP) secretion/activation. All experiments were performed in vitro using an EC cell line, HEC-1A. Cell proliferation was determined using the Promega MTS proliferation assay following 48 h of exposures to different concentrations of LPA (0.1, 1.0 and 10.0 microM). Cell invasion was assessed using a modified Boyden chamber assay with collagen I coated on the membrane. HEC-1A motility was examined by Boyden chamber migration assay as well as the scratch wound closure assay on type I collagen. MMP secretion/activation in HEC-1A conditioned medium was detected by gelatin zymography. MMP-7 mRNA expression was determined using real-time PCR. uPA activity was measured using a coupled colorimetric assay. LPA, at the concentrations of 0.1 and 1.0 microM, significantly induced the proliferation of HEC-1A cells (p0.05). Gelatin zymogram showed that HEC-1A cells secreted high levels of MMP-7, while MMP-2 and MMP-9 are barely detectable. In addition, LPA significantly enhanced uPA activity in HEC-1A conditioned medium in a concentration-dependent manner. LPA is a potent modulator of cellular proliferation and invasion for EC cells. It also has the capacity to stimulate the secretion/activity of uPA and MMP-7. Those results suggest that LPA is a bioactive modulator of EC microenvironment and may have a distinct regulation mechanism as observed in epithelial ovarian cancer. Copyright 2009. Published by Elsevier Inc.

  12. Loss of Proliferation and Antigen Presentation Activity following Internalization of Polydispersed Carbon Nanotubes by Primary Lung Epithelial Cells

    Science.gov (United States)

    Kumari, Mandavi; Sachar, Sumedha; Saxena, Rajiv K.

    2012-01-01

    Interactions between poly-dispersed acid functionalized single walled carbon nanotubes (AF-SWCNTs) and primary lung epithelial (PLE) cells were studied. Peritoneal macrophages (PMs, known phagocytic cells) were used as positive controls in this study. Recovery of live cells from cultures of PLE cells and PMs was significantly reduced in the presence of AF-SWCNTs, in a time and dose dependent manner. Both PLE cells as well as PMs could take up fluorescence tagged AF-SWCNTs in a time dependent manner and this uptake was significantly blocked by cytochalasin D, an agent that blocks the activity of acto-myosin fibers and therefore the phagocytic activity of cells. Confocal microscopic studies confirmed that AF-SWCNTs were internalized by both PLE cells and PMs. Intra-trachially instilled AF-SWCNTs could also be taken up by lung epithelial cells as well as alveolar macrophages. Freshly isolated PLE cells had significant cell division activity and cell cycling studies indicated that treatment with AF-SWCNTs resulted in a marked reduction in S-phase of the cell cycle. In a previously standardized system to study BCG antigen presentation by PLE cells and PMs to sensitized T helper cells, AF-SWCNTs could significantly lower the antigen presentation ability of both cell types. These results show that mouse primary lung epithelial cells can efficiently internalize AF-SWCNTs and the uptake of nanotubes interfered with biological functions of PLE cells including their ability to present BCG antigens to sensitized T helper cells. PMID:22384094

  13. Nuclear receptor corepressor-dependent repression of peroxisome-proliferator-activated receptor delta-mediated transactivation

    DEFF Research Database (Denmark)

    Krogsdam, Anne-M; Nielsen, Curt A F; Neve, Søren

    2002-01-01

    delta-RXR alpha heterodimer bound to an acyl-CoA oxidase (ACO)-type peroxisome-proliferator response element recruited a glutathione S-transferase-NCoR fusion protein in a ligand-independent manner. Contrasting with most other nuclear receptors, PPAR delta was found to interact equally well......The nuclear receptor corepressor (NCoR) was isolated as a peroxisome-proliferator-activated receptor (PPAR) delta interacting protein using the yeast two-hybrid system. NCoR interacted strongly with the ligand-binding domain of PPAR delta, whereas interactions with the ligand-binding domains...

  14. Telmisartan prevents weight gain and obesity through activation of peroxisome proliferator-activated receptor-delta-dependent pathways

    DEFF Research Database (Denmark)

    He, Hongbo; Yang, Dachun; Ma, Liqun

    2010-01-01

    Telmisartan shows antihypertensive and several pleiotropic effects that interact with metabolic pathways. In the present study we tested the hypothesis that telmisartan prevents adipogenesis in vitro and weight gain in vivo through activation of peroxisome proliferator-activated receptor (PPAR)-d...

  15. Peroxisome proliferator-activated receptor gamma coactivator-1 alpha acts as a tumor suppressor in hepatocellular carcinoma.

    Science.gov (United States)

    Liu, Rui; Zhang, Haiyang; Zhang, Yan; Li, Shuang; Wang, Xinyi; Wang, Xia; Wang, Cheng; Liu, Bin; Zen, Ke; Zhang, Chen-Yu; Zhang, Chunni; Ba, Yi

    2017-04-01

    Peroxisome proliferator-activated receptor gamma coactivator-1 alpha plays a crucial role in regulating the biosynthesis of mitochondria, which is closely linked to the energy metabolism in various tumors. This study investigated the regulatory role of peroxisome proliferator-activated receptor gamma coactivator-1 alpha in the pathogenesis of hepatocellular carcinoma. In this study, the changes of peroxisome proliferator-activated receptor gamma coactivator-1 alpha messenger RNA levels between normal human liver and hepatocellular carcinoma tissue were examined by quantitative reverse transcription polymerase chain reaction. Knockdown of peroxisome proliferator-activated receptor gamma coactivator-1 alpha was conducted by RNA interference in the human liver cell line L02, while overexpression of peroxisome proliferator-activated receptor gamma coactivator-1 alpha was conducted by adenovirus encoding peroxisome proliferator-activated receptor gamma coactivator-1 alpha complementary DNA in the human hepatocarcinoma cell line HepG2. Cellular morphological changes were observed via optical and electron microscopy. Cellular apoptosis was determined by Hoechst 33258 staining. In addition, the expression levels of 21,400 genes in tissues and cells were detected by microarray. It was shown that peroxisome proliferator-activated receptor gamma coactivator-1 alpha expression was significantly downregulated in hepatocellular carcinoma compared with normal liver tissues. After knockdown of peroxisome proliferator-activated receptor gamma coactivator-1 alpha expression in L02 cells, cells reverted to immature and dedifferentiated morphology exhibiting cancerous tendency. Apoptosis occurred in the HepG2 cells after transfection by adenovirus encoding peroxisome proliferator-activated receptor gamma coactivator-1 alpha. Microarray analysis showed consistent results. The results suggest that peroxisome proliferator-activated receptor gamma coactivator-1 alpha acts as a tumor

  16. Oleamide activates peroxisome proliferator-activated receptor gamma (PPARγ in vitro

    Directory of Open Access Journals (Sweden)

    Dionisi Mauro

    2012-05-01

    Full Text Available Abstract Background Oleamide (ODA is a fatty acid primary amide first identified in the cerebrospinal fluid of sleep-deprived cats, which exerts effects on vascular and neuronal tissues, with a variety of molecular targets including cannabinoid receptors and gap junctions. It has recently been reported to exert a hypolipidemic effect in hamsters. Here, we have investigated the nuclear receptor family of peroxisome proliferator-activated receptors (PPARs as potential targets for ODA action. Results Activation of PPARα, PPARβ and PPARγ was assessed using recombinant expression in Chinese hamster ovary cells with a luciferase reporter gene assay. Direct binding of ODA to the ligand binding domain of each of the three PPARs was monitored in a cell-free fluorescent ligand competition assay. A well-established assay of PPARγ activity, the differentiation of 3T3-L1 murine fibroblasts into adipocytes, was assessed using an Oil Red O uptake-based assay. ODA, at 10 and 50 μM, was able to transactivate PPARα, PPARβ and PPARγ receptors. ODA bound to the ligand binding domain of all three PPARs, although complete displacement of fluorescent ligand was only evident for PPARγ, at which an IC50 value of 38 μM was estimated. In 3T3-L1 cells, ODA, at 10 and 20 μM, induced adipogenesis. Conclusions We have, therefore, identified a novel site of action of ODA through PPAR nuclear receptors and shown how ODA should be considered as a weak PPARγ ligand in vitro.

  17. TET2 Regulates Mast Cell Differentiation and Proliferation through Catalytic and Non-catalytic Activities

    Directory of Open Access Journals (Sweden)

    Sara Montagner

    2016-05-01

    Full Text Available Summary: Dioxygenases of the TET family impact genome functions by converting 5-methylcytosine (5mC in DNA to 5-hydroxymethylcytosine (5hmC. Here, we identified TET2 as a crucial regulator of mast cell differentiation and proliferation. In the absence of TET2, mast cells showed disrupted gene expression and altered genome-wide 5hmC deposition, especially at enhancers and in the proximity of downregulated genes. Impaired differentiation of Tet2-ablated cells could be relieved or further exacerbated by modulating the activity of other TET family members, and mechanistically it could be linked to the dysregulated expression of C/EBP family transcription factors. Conversely, the marked increase in proliferation induced by the loss of TET2 could be rescued exclusively by re-expression of wild-type or catalytically inactive TET2. Our data indicate that, in the absence of TET2, mast cell differentiation is under the control of compensatory mechanisms mediated by other TET family members, while proliferation is strictly dependent on TET2 expression. : The impact of TET enzymes on gene expression and cell function is incompletely understood. Montagner et al. investigate the TET-mediated regulation of mast cell differentiation and function, uncover transcriptional pathways regulated by TET2, and identify both enzymatic activity-dependent and -independent functions of TET2. Keywords: differentiation, DNA hydroxymethylation, epigenetics, mast cells, proliferation, TET

  18. CHIP promotes thyroid cancer proliferation via activation of the MAPK and AKT pathways

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Li [Department of Pharmacy, Urumchi General Hospital of Lanzhou Military Region, Urumchi, Xinjiang 830000 (China); Liu, Lianyong [Medical College of Soochow University, Suzhou, Jiangsu 215123 (China); Department of Endocrinology, Shanghai Punan Hospital, Shanghai 200125 (China); He, Xiaohua; Shen, Yunling; Liu, Xuerong; Wei, Jing; Yu, Fang [Department of Endocrinology, Urumchi General Hospital of Lanzhou Military Region, Urumchi, Xinjiang 830000 (China); Tian, Jianqing, E-mail: jianqing0991@163.com [Department of Endocrinology, Urumchi General Hospital of Lanzhou Military Region, Urumchi, Xinjiang 830000 (China)

    2016-08-26

    The carboxyl terminus of Hsp70-interacting protein (CHIP) is a U box-type ubiquitin ligase that plays crucial roles in various biological processes, including tumor progression. To date, the functional mechanism of CHIP in thyroid cancer remains unknown. Here, we obtained evidence of upregulation of CHIP in thyroid cancer tissues and cell lines. CHIP overexpression markedly enhanced thyroid cancer cell viability and colony formation in vitro and accelerated tumor growth in vivo. Conversely, CHIP knockdown impaired cell proliferation and tumor growth. Notably, CHIP promoted cell growth through activation of MAPK and AKT pathways, subsequently decreasing p27 and increasing cyclin D1 and p-FOXO3a expression. Our findings collectively indicate that CHIP functions as an oncogene in thyroid cancer, and is therefore a potential therapeutic target for this disease. - Highlights: • CHIP is significantly upregulated in thyroid cancer cells. • Overexpression of CHIP facilitates proliferation and tumorigenesis of thyroid cancer cells. • Silencing of CHIP inhibits the proliferation and tumorigenesis of thyroid cancer cells. • CHIP promotes thyroid cancer cell proliferation via activating the MAPK and AKT pathways.

  19. The Phagocyte, Metchnikoff, and the Foundation of Immunology.

    Science.gov (United States)

    Teti, Giuseppe; Biondo, Carmelo; Beninati, Concetta

    2016-04-01

    Since the ability of some cells to engulf particulate material was observed before Metchnikoff, he did not "discover" phagocytosis, as is sometimes mentioned in textbooks. Rather, he assigned to particle internalization the role of defending the host against noxious stimuli, which represented a new function relative to the previously recognized task of intracellular digestion. With this proposal, Metchnikoff built the conceptual framework within which immunity could finally be seen as an active host function triggered by noxious stimuli. In this sense, Metchnikoff can be rightly regarded as the father of all immunological sciences and not only of innate immunity or myeloid cell biology. Moreover, the recognition properties of his phagocyte fit surprisingly well with recent discoveries and modern models of immune sensing. For example, rather than assigning to immune recognition exclusively the function of eliminating nonself components (as others did after him), Metchnikoff viewed phagocytes as homeostatic agents capable of monitoring the internal environment and promoting tissue remodeling, thereby continuously defining the identity of the organism. No doubt, Metchnikoff's life and creativity can provide, still today, a rich source of inspiration.

  20. Increased p21ras activity in human fibroblasts transduced with survivin enhances cell proliferation

    International Nuclear Information System (INIS)

    Temme, Achim; Diestelkoetter-Bachert, Petra; Schmitz, Marc; Morgenroth, Agnieszka; Weigle, Bernd; Rieger, Michael A.; Kiessling, Andrea; Rieber, E. Peter

    2005-01-01

    Survivin is critically involved in mitosis and when overexpressed enhances the activity of the Aurora B kinase, a serine-threonine kinase belonging to the family of oncogenic Aurora/IpI1p-related kinases. Both proteins interact with Ras GTPase-activating protein suggesting an impact on the Ras pathway. This study aimed at defining the role of survivin in proliferation and potential transformation of cells. When survivin was overexpressed in normal human lung fibroblasts, the characteristic track lanes of fibroblasts were disturbed and the rate of cell proliferation was increased. An enhanced level of p21 ras mRNA and protein expression and concomitant rise in levels of activated p21 ras were observed. Despite increased proliferation cell survival remained dependent on serum and cells were not able to form colonies in soft agar assays. These data suggest that overexpression of survivin increases cell growth but, despite the increase in active p21 ras , is not sufficient to transform primary cells. Yet, in addition to its anti-apoptotic function it might contribute to the accelerated growth of tumour cells by increasing p21 ras activity

  1. Protease-activated receptor 2 modulates proliferation and invasion of oral squamous cell carcinoma cells.

    Science.gov (United States)

    Al-Eryani, Kamal; Cheng, Jun; Abé, Tatsuya; Maruyama, Satoshi; Yamazaki, Manabu; Babkair, Hamzah; Essa, Ahmed; Saku, Takashi

    2015-07-01

    Based on our previous finding that protease-activated receptor 2 (PAR-2) regulates hemophagocytosis of oral squamous cell carcinoma (SCC) cells, which induces their heme oxygenase 1-dependent keratinization, we have formulated a hypothesis that PAR-2 functions in wider activities of SCC cells. To confirm this hypothesis, we investigated immunohistochemical profiles of PAR-2 in oral SCC tissues and its functional roles in cell proliferation and invasion in SCC cells in culture. The PAR-2 expression modes were determined in 48 surgical tissue specimens of oral SCC. Using oral SCC-derived cell systems, we determined both gene and protein expression levels of PAR-2. SCC cell proliferation and invasive properties were also examined in conditions in which PAR-2 was activated by the synthetic peptide SLIGRL. PAR-2 was immunolocalized in oral SCC and carcinoma in situ cells, especially in those on the periphery of carcinoma cell foci (100% of cases), but not in normal oral epithelia. Its expression at both gene and protein levels was confirmed in 3 oral SCC cell lines including ZK-1. Activation of PAR-2 induced ZK-1 cell proliferation in a dose-dependent manner. PAR-2-activated ZK-1 cells invaded faster than nonactivated ones. The expression of PAR-2 is specific to oral malignancies, and PAR-2 regulates the growth and invasion of oral SCC cells. Copyright © 2015 Elsevier Inc. All rights reserved.

  2. Differential expression of peroxisome proliferator activated receptor gamma and cyclin D1 does not affect proliferation of asthma- and non-asthma-derived airway smooth muscle cells

    NARCIS (Netherlands)

    Lau, Justine Y; Oliver, Brian G; Moir, Lyn M; Black, Judith L; Burgess, Janette K

    UNLABELLED: PPARgamma levels in asthma- and non-asthma-derived airway smooth muscle cells and PPARgamma activation-induced cell proliferation were investigated. In the presence of FBS, PPARgamma levels were higher in subconfluent asthma-derived cells but lower in confluent cells compared with

  3. Effects of Enrofloxacin on Porcine Phagocytic Function

    Science.gov (United States)

    Schoevers, E. J.; van Leengoed, L. A. M. G.; Verheijden, J. H. M.; Niewold, T. A.

    1999-01-01

    The interaction between enrofloxacin and porcine phagocytes was studied with clinically relevant concentrations of enrofloxacin. Enrofloxacin accumulated in phagocytes, with cellular concentration/extracellular concentration ratios of 9 for polymorphonuclear leukocytes (PMNs) and 5 for alveolar macrophages (AMs). Cells with accumulated enrofloxacin brought into enrofloxacin-free medium released approximately 80% (AMs) to 90% (PMNs) of their enrofloxacin within the first 10 min, after which no further release was seen. Enrofloxacin affected neither the viability of PMNs and AMs nor the chemotaxis of PMNs at concentrations ranging from 0 to 10 μg/ml. Enrofloxacin (0.5 μg/ml) did not alter the capability of PMNs and AMs to phagocytize fluorescent microparticles or Actinobacillus pleuropneumoniae, Pasteurella multocida, and Staphylococcus aureus. Significant differences in intracellular killing were seen with enrofloxacin at 5× the MIC compared with that for controls not treated with enrofloxacin. PMNs killed all S. aureus isolates in 3 h with or without enrofloxacin. Intracellular S. aureus isolates in AMs were less susceptible than extracellular S. aureus isolates to the bactericidal effect of enrofloxacin. P. multocida was not phagocytosed by PMNs. AMs did not kill P. multocida, and similar intra- and extracellular reductions of P. multocida isolates by enrofloxacin were found. Intraphagocytic killing of A. pleuropneumoniae was significantly enhanced by enrofloxacin at 5× the MIC in both PMNs and AMs. AMs are very susceptible to the A. pleuropneumoniae cytotoxin. This suggests that in serologically naive pigs the enhancing effect of enrofloxacin on the bactericidal action of PMNs may have clinical relevance. PMID:10471554

  4. TGF-β2 inhibits AKT activation and FGF-2-induced corneal endothelial cell proliferation

    International Nuclear Information System (INIS)

    Lu Jiawei; Lu Zhenyu; Reinach, Peter

    2006-01-01

    The corneal endothelial cells form a boundary layer between anterior chamber and cornea. This single cell layer is important to maintain cornea transparency by eliciting net fluid transport into the anterior chamber. Injuries of the corneal endothelial layer in humans lead to corneal swelling and translucence. This hindrance is thought to be due to limited proliferative capacity of the endothelial layer. Fibroblast growth factor 2 (FGF-2) and transforming growth factor-beta 2 (TGF-β2) are both found in aqueous humor, and these two cytokines promote and inhibit cell growth, respectively. The intracellular signaling mechanisms by which TGF-β2 suppresses the mitogenic response to FGF-2, however, remain unclear. We have addressed this question by investigating potential crosstalk between FGF-2-induced and TGF-β2-regulated intracellular signaling events in cultured bovine corneal endothelial (BCE) cells. We found that TGF-β2 and FGF-2 oppositely affect BCE cell proliferation and TGF-β2 can override the stimulating effects of FGF-2 by increasing COX-2 expression in these cells. Consistent with these findings, overexpression of COX-2 significantly reduced FGF-2-induced cell proliferation whereas a COX-2 specific inhibitor NS398 reversed the effect of TGF-β2 on FGF-2-induced cell proliferation. The COX-2 product prostaglandin E2 (PGE-2) blocks FGF-2-induced cell proliferation. Whereas FGF-2 stimulates cell proliferation by activating the AKT pathway, TGF-β2 and PGE-2 both inhibit this pathway. In accordance with the effect of PGE-2, cAMP also inhibits FGF-2-induced AKT activation. These findings suggest that the mitogenic response to FGF-2 in vivo in the corneal endothelial layer may be inhibited by TGF-β2-induced suppression of the PI3-kinase/AKT signaling pathway

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

    International Nuclear Information System (INIS)

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

    2017-01-01

    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. - Highlights: • Bioactive molecules modified surface is a strategy to design biomimicry scaffold. • Bi-functional Tat-derived peptide (R-pept) enhanced MSCs adhesion and proliferation. • R-pept showed similar influences to fibronectin on FA formation and attachment.

  6. Medium chain fatty acids are selective peroxisome proliferator activated receptor (PPAR) γ activators and pan-PPAR partial agonists

    NARCIS (Netherlands)

    Liberato, Marcelo Vizoná; Nascimento, Alessandro S; Ayers, Steven D; Lin, Jean Z; Cvoro, Aleksandra; Silveira, Rodrigo L; Martínez, Leandro; Souza, Paulo C T; Saidemberg, Daniel; Deng, Tuo; Amato, Angela Angelica; Togashi, Marie; Hsueh, Willa A; Phillips, Kevin; Palma, Mário Sérgio; Neves, Francisco A R; Skaf, Munir S; Webb, Paul; Polikarpov, Igor

    2012-01-01

    Thiazolidinediones (TZDs) act through peroxisome proliferator activated receptor (PPAR) γ to increase insulin sensitivity in type 2 diabetes (T2DM), but deleterious effects of these ligands mean that selective modulators with improved clinical profiles are needed. We obtained a crystal structure of

  7. Factor Xa stimulates fibroblast procollagen production, proliferation, and calcium signaling via PAR1 activation

    International Nuclear Information System (INIS)

    Blanc-Brude, Olivier P.; Archer, Fabienne; Leoni, Patricia; Derian, Claudia; Bolsover, Steven; Laurent, Geoffrey J.; Chambers, Rachel C.

    2005-01-01

    Fibroblast proliferation and procollagen production are central features of tissue repair and fibrosis. In addition to its role in blood clotting, the coagulation cascade proteinase thrombin can contribute to tissue repair by stimulating fibroblasts via proteolytic activation of proteinase-activated receptor-1 (PAR 1 ). During hemostasis, the coagulation cascade proteinase factor X is converted into factor Xa. We have previously shown that factor Xa upregulates fibroblast proliferation via production of autocrine PDGF. In this study, we further examined the effects of factor Xa on fibroblast function and aimed to identify its signaling receptor. We showed that factor Xa stimulates procollagen promoter activity and protein production by human and mouse fibroblasts. This effect was independent of PDGF and thrombin production, but dependent on factor Xa proteolytic activity. We also showed that PAR 1 -deficient mouse fibroblasts did not upregulate procollagen production, mobilize cytosolic calcium, or proliferate in response to factor Xa. Desensitization techniques and PAR 1 -specific agonists and inhibitors were used to demonstrate that PAR 1 mediates factor Xa signaling in human fibroblasts. This is the first report that factor Xa stimulates extracellular matrix production. In contrast with endothelial cells and vascular smooth muscle cells, fibroblasts appear to be the only cell type in which the effects of factor Xa are mediated mainly via PAR 1 and not PAR 2 . These findings are critical for our understanding of tissue repair and fibrotic mechanisms, and for the design of novel approaches to inhibit the profibrotic effects of the coagulation cascade without compromising blood hemostasis

  8. Activated STAT5 Confers Resistance to Intestinal Injury by Increasing Intestinal Stem Cell Proliferation and Regeneration

    Directory of Open Access Journals (Sweden)

    Shila Gilbert

    2015-02-01

    Full Text Available Intestinal epithelial stem cells (IESCs control the intestinal homeostatic response to inflammation and regeneration. The underlying mechanisms are unclear. Cytokine-STAT5 signaling regulates intestinal epithelial homeostasis and responses to injury. We link STAT5 signaling to IESC replenishment upon injury by depletion or activation of Stat5 transcription factor. We found that depletion of Stat5 led to deregulation of IESC marker expression and decreased LGR5+ IESC proliferation. STAT5-deficient mice exhibited worse intestinal histology and impaired crypt regeneration after γ-irradiation. We generated a transgenic mouse model with inducible expression of constitutively active Stat5. In contrast to Stat5 depletion, activation of STAT5 increased IESC proliferation, accelerated crypt regeneration, and conferred resistance to intestinal injury. Furthermore, ectopic activation of STAT5 in mouse or human stem cells promoted LGR5+ IESC self-renewal. Accordingly, STAT5 promotes IESC proliferation and regeneration to mitigate intestinal inflammation. STAT5 is a functional therapeutic target to improve the IESC regenerative response to gut injury.

  9. Innate Immunity to Leishmania Infection: Within Phagocytes

    Directory of Open Access Journals (Sweden)

    Marcela Freitas Lopes

    2014-01-01

    Full Text Available Infection by Leishmania takes place in the context of inflammation and tissue repair. Besides tissue resident macrophages, inflammatory macrophages and neutrophils are recruited to the infection site and serve both as host cells and as effectors against infection. Recent studies suggest additional important roles for monocytes and dendritic cells. This paper addresses recent experimental findings regarding the regulation of Leishmania major infection by these major phagocyte populations. In addition, the role of IL-4 on dendritic cells and monocytes is discussed.

  10. Viability, Apoptosis, Proliferation, Activation, and Cytokine Secretion of Human Keratoconus Keratocytes after Cross-Linking

    Directory of Open Access Journals (Sweden)

    Xuefei Song

    2015-01-01

    Full Text Available Purpose. The purpose of this study was to determine the impact of cross-linking (CXL on viability, apoptosis, proliferation, activation, and cytokine secretion of human keratoconus (KC keratocytes, in vitro. Methods. Primary KC keratocytes were cultured in DMEM/Ham’s F12 medium supplemented with 10% FCS and underwent UVA illumination (370 nm, 2 J/cm2 during exposure to 0.1% riboflavin and 20% Dextran in PBS. Twenty-four hours after CXL, viability was assessed using Alamar blue assay; apoptosis using APO-DIRECT Kit; proliferation using ELISA-BrdU kit; and CD34 and alpha-smooth muscle actin (α-SMA expression using flow cytometry. Five and 24 hours after CXL, FGFb, HGF, TGFβ1, VEGF, KGF, IL-1β, IL-6, and IL-8 secretion was measured using enzyme-linked-immunoabsorbent assay (ELISA. Results. Following CXL, cell viability and proliferation decreased (P0.06. Five hours after CXL, FGFb secretion increased significantly (P=0.037; however no other cytokine secretion differed significantly from controls after 5 or 24 hours (P>0.12. Conclusions. Cross-linking decreases viability, triggers apoptosis, and inhibits proliferation, without an impact on multipotent hematopoietic stem cell transformation and myofibroblastic transformation of KC keratocytes. CXL triggers FGFb secretion of KC keratocytes transiently (5 hours, normalizing after 24 hours.

  11. Immunotoxicity of perfluorooctanoic acid and perfluorooctane sulfonate and the role of peroxisome proliferator-activated receptor alpha

    Science.gov (United States)

    Peroxisome proliferators, including perfluorooctanoic acid (PFOA), are environmentally widespread and persistent and multiple toxicities have been reported in experimental animals and humans. These compounds trigger biological activity via activation of the alpha isotype of pero...

  12. Metabolic adaptation to intermittent fasting is independent of peroxisome proliferator-activated receptor alpha

    OpenAIRE

    Li, Guolin; Brocker, Chad N.; Yan, Tingting; Xie, Cen; Krausz, Kristopher W.; Xiang, Rong; Gonzalez, Frank J.

    2017-01-01

    Background: Peroxisome proliferator-activated receptor alpha (PPARA) is a major regulator of fatty acid oxidation and severe hepatic steatosis occurs during acute fasting in Ppara-null mice. Thus, PPARA is considered an important mediator of the fasting response; however, its role in other fasting regiments such as every-other-day fasting (EODF) has not been investigated. Methods: Mice were pre-conditioned using either a diet containing the potent PPARA agonist Wy-14643 or an EODF regimen ...

  13. Hedgehog signaling activation induces stem cell proliferation and hormone release in the adult pituitary gland

    OpenAIRE

    Joanna Pyczek; Rolf Buslei; David Schult; Annett Hölsken; Michael Buchfelder; Ina Heß; Heidi Hahn; Anja Uhmann

    2016-01-01

    Hedgehog (HH) signaling is known to be essential during the embryonal development of the pituitary gland but the knowledge about its role in the adult pituitary and in associated tumors is sparse. In this report we investigated the effect of excess Hh signaling activation in murine pituitary explants and analyzed the HH signaling status of human adenopituitary lobes and a large cohort of pituitary adenomas. Our data show that excess Hh signaling led to increased proliferation of Sox2(+) and S...

  14. Differential Effects of Tacrolimus versus Sirolimus on the Proliferation, Activation and Differentiation of Human B Cells.

    Directory of Open Access Journals (Sweden)

    Opas Traitanon

    Full Text Available The direct effect of immunosuppressive drugs calcineurin inhibitor (Tacrolimus, TAC and mTOR inhibitor (Sirolimus, SRL on B cell activation, differentiation and proliferation is not well documented. Purified human B cells from healthy volunteers were stimulated through the B Cell Receptor with Anti-IgM + anti-CD40 + IL21 in the absence / presence of TAC or SRL. A variety of parameters of B cell activity including activation, differentiation, cytokine productions and proliferation were monitored by flow cytometry. SRL at clinically relevant concentrations (6 ng/ml profoundly inhibited CD19(+ B cell proliferation compared to controls whereas TAC at similar concentrations had a minimal effect. CD27(+ memory B cells were affected more by SRL than naïve CD27- B cells. SRL effectively blocked B cell differentiation into plasma cells (CD19(+CD138(+ and Blimp1(+/Pax5(low cells even at low dose (2 ng/ml, and totally eliminated them at 6 ng/ml. SRL decreased absolute B cell counts, but the residual responding cells acquired an activated phenotype (CD25(+/CD69(+ and increased the expression of HLA-DR. SRL-treated stimulated B cells on a per cell basis were able to enhance the proliferation of allogeneic CD4(+CD25(- T cells and induce a shift toward the Th1 phenotype. Thus, SRL and TAC have different effects on B lymphocytes. These data may provide insights into the clinical use of these two agents in recipients of solid organ transplants.

  15. Silencing Nrf2 impairs glioma cell proliferation via AMPK-activated mTOR inhibition

    Energy Technology Data Exchange (ETDEWEB)

    Jia, Yue [Department of Neurosurgery, Jinling Hospital, School of Medicine, Nanjing University, 305 East Zhongshan Road, Nanjing 210002, Jiangsu Province (China); Wang, Handong, E-mail: njhdwang@hotmail.com [Department of Neurosurgery, Jinling Hospital, School of Medicine, Nanjing University, 305 East Zhongshan Road, Nanjing 210002, Jiangsu Province (China); Wang, Qiang [Department of Neurosurgery, Jinling Hospital, School of Medicine, Nanjing University, 305 East Zhongshan Road, Nanjing 210002, Jiangsu Province (China); Ding, Hui [Department of Neurosurgery, Jinling Hospital, School of Medicine, Southern Medical University (Guangzhou), 305 East Zhongshan Road, Nanjing 210002, Jiangsu Province (China); Wu, Heming [Department of Neurosurgery, Nanjing Jingdu Hospital, No. 34, Biao 34, Yanggongjing Road, Nanjing 210002, Jiangsu Province (China); Pan, Hao [Department of Neurosurgery, Jinling Hospital, School of Medicine, Nanjing University, 305 East Zhongshan Road, Nanjing 210002, Jiangsu Province (China)

    2016-01-15

    Gliomas are the leading cause of death among adults with primary brain malignancies. Treatment for malignant gliomas remains limited, and targeted therapies have been incompletely explored. Nuclear factor erythroid 2-related factor 2 (Nrf2), a key transcription regulator for antioxidant and detoxification enzymes, is abundantly expressed in cancer cells. In this study, the role and mechanism of Nrf2 in cancer cell proliferation was investigated in multiple glioma cell lines. We first evaluated the expression patterns of Nrf2 in four glioma cell lines and found all four cell lines expressed Nrf2, but the highest level was observed in U251 cells. We further evaluated the biological functions of Nrf2 in U251 glioma cell proliferation by specific inhibition of Nrf2 using short hairpin RNA (shRNA). We found that Nrf2 depletion inhibited glioma cell proliferation. Nrf2 depletion also decreased colony formation in U251 cells stably expressing Nrf2 shRNA compared to scrambled control shRNA. Moreover, suppression of Nrf2 expression could lead to ATP depletion (with concomitant rise in AMP/ATP ratio) and consequently to AMPK-activated mTOR inhibition. Finally, activation of adenosine monophosphate–activated protein kinase (AMPK) by treated with phenformin, an AMPK agonist, can mimic the inhibitory effect of Nrf2 knockdown in U251 cells. In conclusion, our findings will shed light to the role and mechanism of Nrf2 in regulating glioma proliferation via ATP-depletion-induced AMPK activation and consequent mTOR inhibition, a novel insight into our understanding the role and mechanism of Nrf2 in glioma pathoetiology. To our knowledge, this is also the first report to provide a rationale for the implication of cross-linking between Nrf2 and mTOR signaling.

  16. Deregulated GSK3β activity in colorectal cancer: Its association with tumor cell survival and proliferation

    International Nuclear Information System (INIS)

    Shakoori, Abbas; Ougolkov, Andrei; Yu Zhiwei; Zhang Bin; Modarressi, Mohammad H.; Billadeau, Daniel D.; Mai, Masayoshi; Takahashi, Yutaka; Minamoto, Toshinari

    2005-01-01

    Glycogen synthase kinase 3β (GSK3β) reportedly has opposing roles, repressing Wnt/β-catenin signaling on the one hand but maintaining cell survival and proliferation through the NF-κB pathway on the other. The present investigation was undertaken to clarify the roles of GSK3β in human cancer. In colon cancer cell lines and colorectal cancer patients, levels of GSK3β expression and amounts of its active form were higher in tumor cells than in their normal counterparts; these findings were independent of nuclear accumulation of β-catenin oncoprotein in the tumor cells. Inhibition of GSK3β activity by phosphorylation was defective in colorectal cancers but preserved in non-neoplastic cells and tissues. Strikingly, inhibition of GSK3β activity by chemical inhibitors and its expression by RNA interference targeting GSK3β induced apoptosis and attenuated proliferation of colon cancer cells in vitro. Our findings demonstrate an unrecognized role of GSK3β in tumor cell survival and proliferation other than its predicted role as a tumor suppressor, and warrant proposing this kinase as a potential therapeutic target in colorectal cancer

  17. Statins meditate anti-atherosclerotic action in smooth muscle cells by peroxisome proliferator-activated receptor-γ activation

    Energy Technology Data Exchange (ETDEWEB)

    Fukuda, Kazuki [Department of Metabolic Medicine, Faculty of Life Sciences, Kumamoto University, Kumamoto (Japan); Matsumura, Takeshi, E-mail: takeshim@gpo.kumamoto-u.ac.jp [Department of Metabolic Medicine, Faculty of Life Sciences, Kumamoto University, Kumamoto (Japan); Senokuchi, Takafumi; Ishii, Norio; Kinoshita, Hiroyuki; Yamada, Sarie; Murakami, Saiko [Department of Metabolic Medicine, Faculty of Life Sciences, Kumamoto University, Kumamoto (Japan); Nakao, Saya [Department of Environmental & Symbiotic Sciences, Prefectural University of Kumamoto, Kumamoto (Japan); Motoshima, Hiroyuki; Kondo, Tatsuya; Kukidome, Daisuke; Kawasaki, Shuji [Department of Metabolic Medicine, Faculty of Life Sciences, Kumamoto University, Kumamoto (Japan); Kawada, Teruo [Laboratory of Nutrition Chemistry, Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Kyoto (Japan); Nishikawa, Takeshi; Araki, Eiichi [Department of Metabolic Medicine, Faculty of Life Sciences, Kumamoto University, Kumamoto (Japan)

    2015-01-30

    Highlights: • Statins induce PPARγ activation in vascular smooth muscle cells. • Statin-induced PPARγ activation is mediated by COX-2 expression. • Statins suppress cell migration and proliferation in vascular smooth muscle cells. • Statins inhibit LPS-induced inflammatory responses by PPARγ activation. • Fluvastatin suppress the progression of atherosclerosis and induces PPARγ activation in the aorta of apoE-deficient mice. - Abstract: The peroxisome proliferator-activated receptor-γ (PPARγ) is an important regulator of lipid and glucose metabolism, and its activation is reported to suppress the progression of atherosclerosis. We have reported that 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins) activate PPARγ in macrophages. However, it is not yet known whether statins activate PPARγ in other vascular cells. In the present study, we investigated whether statins activate PPARγ in smooth muscle cells (SMCs) and endothelial cells (ECs) and thus mediate anti-atherosclerotic effects. Human aortic SMCs (HASMCs) and human umbilical vein ECs (HUVECs) were used in this study. Fluvastatin and pitavastatin activated PPARγ in HASMCs, but not in HUVECs. Statins induced cyclooxygenase-2 (COX-2) expression in HASMCs, but not in HUVECs. Moreover, treatment with COX-2-siRNA abrogated statin-mediated PPARγ activation in HASMCs. Statins suppressed migration and proliferation of HASMCs, and inhibited lipopolysaccharide-induced expression of monocyte chemoattractant protein-1 (MCP-1) and tumor necrosis factor-α (TNF-α) in HASMCs. These effects of statins were abrogated by treatment with PPARγ-siRNA. Treatment with statins suppressed atherosclerotic lesion formation in Apoe{sup −/−} mice. In addition, transcriptional activity of PPARγ and CD36 expression were increased, and the expression of MCP-1 and TNF-α was decreased, in the aorta of statin-treated Apoe{sup −/−} mice. In conclusion, statins mediate anti-atherogenic effects

  18. Statins meditate anti-atherosclerotic action in smooth muscle cells by peroxisome proliferator-activated receptor-γ activation

    International Nuclear Information System (INIS)

    Fukuda, Kazuki; Matsumura, Takeshi; Senokuchi, Takafumi; Ishii, Norio; Kinoshita, Hiroyuki; Yamada, Sarie; Murakami, Saiko; Nakao, Saya; Motoshima, Hiroyuki; Kondo, Tatsuya; Kukidome, Daisuke; Kawasaki, Shuji; Kawada, Teruo; Nishikawa, Takeshi; Araki, Eiichi

    2015-01-01

    Highlights: • Statins induce PPARγ activation in vascular smooth muscle cells. • Statin-induced PPARγ activation is mediated by COX-2 expression. • Statins suppress cell migration and proliferation in vascular smooth muscle cells. • Statins inhibit LPS-induced inflammatory responses by PPARγ activation. • Fluvastatin suppress the progression of atherosclerosis and induces PPARγ activation in the aorta of apoE-deficient mice. - Abstract: The peroxisome proliferator-activated receptor-γ (PPARγ) is an important regulator of lipid and glucose metabolism, and its activation is reported to suppress the progression of atherosclerosis. We have reported that 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins) activate PPARγ in macrophages. However, it is not yet known whether statins activate PPARγ in other vascular cells. In the present study, we investigated whether statins activate PPARγ in smooth muscle cells (SMCs) and endothelial cells (ECs) and thus mediate anti-atherosclerotic effects. Human aortic SMCs (HASMCs) and human umbilical vein ECs (HUVECs) were used in this study. Fluvastatin and pitavastatin activated PPARγ in HASMCs, but not in HUVECs. Statins induced cyclooxygenase-2 (COX-2) expression in HASMCs, but not in HUVECs. Moreover, treatment with COX-2-siRNA abrogated statin-mediated PPARγ activation in HASMCs. Statins suppressed migration and proliferation of HASMCs, and inhibited lipopolysaccharide-induced expression of monocyte chemoattractant protein-1 (MCP-1) and tumor necrosis factor-α (TNF-α) in HASMCs. These effects of statins were abrogated by treatment with PPARγ-siRNA. Treatment with statins suppressed atherosclerotic lesion formation in Apoe −/− mice. In addition, transcriptional activity of PPARγ and CD36 expression were increased, and the expression of MCP-1 and TNF-α was decreased, in the aorta of statin-treated Apoe −/− mice. In conclusion, statins mediate anti-atherogenic effects through PPAR

  19. Superoxide anions and hydrogen peroxide inhibit proliferation of activated rat stellate cells and induce different modes of cell death

    NARCIS (Netherlands)

    Dunning, Sandra; Hannivoort, Rebekka A.; de Boer, Jan Freark; Buist-Homan, Manon; Faber, Klaas Nico; Moshage, Han

    In chronic liver injury, hepatic stellate cells (HSCs) proliferate and produce excessive amounts of connective tissue causing liver fibrosis and cirrhosis. Oxidative stress has been implicated as a driving force of HSC activation and proliferation, although contradictory results have been described.

  20. Inhibitory efficacy of bufadienolides on Na+,K+-pump activity versus cell proliferation.

    Science.gov (United States)

    Xu, Yinfang; Liu, Xuan; Schwarz, Silvia; Hu, Lihong; Guo, Dean; Gu, Quanbao; Schwarz, Wolfgang

    2016-07-01

    Bufadienolides are cytotoxic drugs that may form the basis for anticancer agents. Due to structural and functional similarity to cardiotonic glycosides, application is restricted. We, therefore, investigated correlation of their putative anticancer effects with inhibition of Na + ,K + pumps. The natural bufalin and three derivatives were tested. The anticancer effects of the drugs were checked by observing their inhibitory effects on proliferation of rat liver cancer cells using MTT assay. Inhibition of Na + ,K + -pump was determined by measuring pump-mediated current of rat α1/β1 and α2/β1 Na + ,K + pumps expressed in Xenopus oocytes. All tested bufadienolides inhibited cell proliferation and Na + ,K + pump activity. An activity coefficient A =100x IC 50 Na,K pump /IC 50 pr o liferation was used to describe drug effectivity as anticancer drug. Natural bufalin exhibited lowest effectivity on cell proliferation, and also the A value for rat α1 isoform was the lowest (0.08), the α2 isoform was much less sensitive ( A =1.00). The highest A values were obtained for the BF238 derivative with A =0.88 and 2.64 for the α1 and α2 isoforms, respectively. Therefore, we suggest that search for bufalin derivatives with high anticancer effect and low affinity for both Na + ,K + pump isoforms may be a promising strategy for development of anticancer drugs.

  1. LIX1 regulates YAP1 activity and controls the proliferation and differentiation of stomach mesenchymal progenitors.

    Science.gov (United States)

    McKey, Jennifer; Martire, Delphine; de Santa Barbara, Pascal; Faure, Sandrine

    2016-04-28

    Smooth muscle cell (SMC) plasticity maintains the balance between differentiated SMCs and proliferative mesenchymal progenitors, crucial for muscular tissue homeostasis. Studies on the development of mesenchymal progenitors into SMCs have proven useful in identifying molecular mechanisms involved in digestive musculature plasticity in physiological and pathological conditions. Here, we show that Limb Expression 1 (LIX1) molecularly defines the population of mesenchymal progenitors in the developing stomach. Using in vivo functional approaches in the chick embryo, we demonstrate that LIX1 is a key regulator of stomach SMC development. We show that LIX1 is required for stomach SMC determination to regulate the expression of the pro-proliferative gene YAP1 and mesenchymal cell proliferation. However, as stomach development proceeds, sustained LIX1 expression has a negative impact on further SMC differentiation and this is associated with a decrease in YAP1 activity. We demonstrate that expression of LIX1 must be tightly regulated to allow fine-tuning of the transcript levels and state of activation of the pro-proliferative transcriptional coactivator YAP1 to regulate proliferation rates of stomach mesenchymal progenitors and their differentiation. Our data highlight dual roles for LIX1 and YAP1 and provide new insights into the regulation of cell density-dependent proliferation, which is essential for the development and homeostasis of organs.

  2. Cell culture density affects the proliferation activity of human adipose tissue stem cells.

    Science.gov (United States)

    Kim, Dae Seong; Lee, Myoung Woo; Ko, Young Jong; Chun, Yong Hoon; Kim, Hyung Joon; Sung, Ki Woong; Koo, Hong Hoe; Yoo, Keon Hee

    2016-01-01

    In this study, we investigated the effect of cell density on the proliferation activity of human mesenchymal stem cells (MSCs) derived from adipose tissue (AT-MSCs) over time in culture. Passage #4 (P4) and #12 (P12) AT-MSCs from two donors were plated at a density of 200 (culture condition 1, CC1) or 5000 (culture condition 2, CC2) cells cm(-2) . After 7 days of incubation, P4 and P12 AT-MSCs cultured in CC1 were thin and spindle-shaped, whereas those cultured in CC2 had extensive cell-to-cell contacts and an expanded cell volume. In addition, P4 and P12 AT-MSCs in CC1 divided more than three times, while those in CC2 divided less than once on average. Flow cytometric analysis using 5(6)-carboxyfluorescein diacetate N-succinimidyl ester dye showed that the fluorescence intensity of AT-MSCs was lower in CC1 than in CC2. Furthermore, expression of proliferation-associated genes, such as CDC45L, CDC20A and KIF20A, in P4 AT-MSCs was higher in CC1 than in CC2, and this difference was also observed in P12 AT-MSCs. These data demonstrated that cell culture density affects the proliferation activity of MSCs, suggesting that it is feasible to design a strategy to prepare suitable MSCs using specific culture conditions. Copyright © 2016 John Wiley & Sons, Ltd.

  3. Hedgehog signal activation coordinates proliferation and differentiation of fetal liver progenitor cells

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    Hirose, Yoshikazu; Itoh, Tohru; Miyajima, Atsushi

    2009-01-01

    Hedgehog (Hh) signaling plays crucial roles in development and homeostasis of various organs. In the adult liver, it regulates proliferation and/or viability of several types of cells, particularly under injured conditions, and is also implicated in stem/progenitor cell maintenance. However, the role of this signaling pathway during the normal developmental process of the liver remains elusive. Although Sonic hedgehog (Shh) is expressed in the ventral foregut endoderm from which the liver derives, the expression disappears at the onset of the liver bud formation, and its possible recurrence at the later stages has not been investigated. Here we analyzed the activation and functional relevance of Hh signaling during the mouse fetal liver development. At E11.5, Shh and an activation marker gene for Hh signaling, Gli1, were expressed in Dlk + hepatoblasts, the fetal liver progenitor cells, and the expression was rapidly decreased thereafter as the development proceeded. In the culture of Dlk + hepatoblasts isolated from the E11.5 liver, activation of Hh signaling stimulated their proliferation and this effect was cancelled by a chemical Hh signaling inhibitor, cyclopamine. In contrast, hepatocyte differentiation of Dlk + hepatoblasts in vitro as manifested by the marker gene expression and acquisition of ammonia clearance activity was significantly inhibited by forced activation of Hh signaling. Taken together, these results demonstrate the temporally restricted manner of Hh signal activation and its role in promoting the hepatoblast proliferation, and further suggest that the pathway needs to be shut off for the subsequent hepatic differentiation of hepatoblasts to proceed normally.

  4. Modulating Estrogen Receptor-related Receptor-α Activity Inhibits Cell Proliferation*

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    Bianco, Stéphanie; Lanvin, Olivia; Tribollet, Violaine; Macari, Claire; North, Sophie; Vanacker, Jean-Marc

    2009-01-01

    High expression of the estrogen receptor-related receptor (ERR)-α in human tumors is correlated to a poor prognosis, suggesting an involvement of the receptor in cell proliferation. In this study, we show that a synthetic compound (XCT790) that modulates the activity of ERRα reduces the proliferation of various cell lines and blocks the G1/S transition of the cell cycle in an ERRα-dependent manner. XCT790 induces, in a p53-independent manner, the expression of the cell cycle inhibitor p21waf/cip1 at the protein, mRNA, and promoter level, leading to an accumulation of hypophosphorylated Rb. Finally, XCT790 reduces cell tumorigenicity in Nude mice. PMID:19546226

  5. [Coactivators in energy metabolism: peroxisome proliferator-activated receptor-gamma coactivator 1 family].

    Science.gov (United States)

    Wang, Rui; Chang, Yong-sheng; Fang, Fu-de

    2009-12-01

    Peroxisome proliferator-activated receptor gamma coactivator 1 (PGC1) family is highly expressed in tissues with high energy metabolism. They coactivate transcription factors in regulating genes engaged in processes such as gluconeogenesis, adipose beta-oxydation, lipoprotein synthesis and secretion, mitochondrial biogenesis, and oxidative metabolism. Protein conformation studies demonstrated that they lack DNA binding domains and act as coactivators through physical interaction with transcription factors. PGC1 activity is regulated at transcription level or by multiple covalent chemical modifications such as phosphorylation, methylation and acetylation/deacetylation. Abnormal expression of PGC1 coactivators usually is closely correlated with diseases such as diabetes, obesity, hyperglycemia, hyperlipemia, and arterial and brain neuron necrosis diseases.

  6. Orbital fluid shear stress promotes osteoblast metabolism, proliferation and alkaline phosphates activity in vitro

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    Aisha, M.D. [Institute of Medical Molecular Biotechnology and Faculty of Medicine, Universiti Teknologi MARA, Sungai Buloh 47000, Selangor (Malaysia); Nor-Ashikin, M.N.K. [Institute of Medical Molecular Biotechnology and Faculty of Medicine, Universiti Teknologi MARA, Sungai Buloh 47000, Selangor (Malaysia); DDH, Universiti Teknologi MARA, ShahAlam 40450, Selangor (Malaysia); Sharaniza, A.B.R. [DDH, Universiti Teknologi MARA, ShahAlam 40450, Selangor (Malaysia); Nawawi, H. [Center for Pathology Diagnostic and Research Laboratories, Clinical Training Center, Universiti Teknologi MARA, Sungai Buloh 47000, Selangor (Malaysia); I-PPerForM, Universiti Teknologi MARA, Selayang 47000 Selangor (Malaysia); Froemming, G.R.A., E-mail: gabriele@salam.uitm.edu.my [Institute of Medical Molecular Biotechnology and Faculty of Medicine, Universiti Teknologi MARA, Sungai Buloh 47000, Selangor (Malaysia); I-PPerForM, Universiti Teknologi MARA, Selayang 47000 Selangor (Malaysia)

    2015-09-10

    Prolonged disuse of the musculoskeletal system is associated with reduced mechanical loading and lack of anabolic stimulus. As a form of mechanical signal, the multidirectional orbital fluid shear stress transmits anabolic signal to bone forming cells in promoting cell differentiation, metabolism and proliferation. Signals are channeled through the cytoskeleton framework, directly modifying gene and protein expression. For that reason, we aimed to study the organization of Normal Human Osteoblast (NHOst) cytoskeleton with regards to orbital fluid shear (OFS) stress. Of special interest were the consequences of cytoskeletal reorganization on NHOst metabolism, proliferation, and osteogenic functional markers. Cells stimulated at 250 RPM in a shaking incubator resulted in the rearrangement of actin and tubulin fibers after 72 h. Orbital shear stress increased NHOst mitochondrial metabolism and proliferation, simultaneously preventing apoptosis. The ratio of RANKL/OPG was reduced, suggesting that orbital shear stress has the potential to inhibit osteoclastogenesis and osteoclast activity. Increase in ALP activity and OCN protein production suggests that stimulation retained osteoblast function. Shear stress possibly generated through actin seemed to hold an anabolic response as osteoblast metabolism and functional markers were enhanced. We hypothesize that by applying orbital shear stress with suitable magnitude and duration as a non-drug anabolic treatment can help improve bone regeneration in prolonged disuse cases. - Highlights: • OFS stress transmits anabolic signals to osteoblasts. • Actin and tubulin fibers are rearranged under OFS stress. • OFS stress increases mitochondrial metabolism and proliferation. • Reduced RANKL/OPG ratio in response to OFS inhibits osteoclastogenesis. • OFS stress prevents apoptosis and stimulates ALP and OCN.

  7. Mast cell tryptase stimulates myoblast proliferation; a mechanism relying on protease-activated receptor-2 and cyclooxygenase-2

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    Côté Claude H

    2011-10-01

    Full Text Available Abstract Background Mast cells contribute to tissue repair in fibrous tissues by stimulating proliferation of fibroblasts through the release of tryptase which activates protease-activated receptor-2 (PAR-2. The possibility that a tryptase/PAR-2 signaling pathway exists in skeletal muscle cell has never been investigated. The aim of this study was to evaluate whether tryptase can stimulate myoblast proliferation and determine the downstream cascade. Methods Proliferation of L6 rat skeletal myoblasts stimulated with PAR-2 agonists (tryptase, trypsin and SLIGKV was assessed. The specificity of the tryptase effect was evaluated with a specific inhibitor, APC-366. Western blot analyses were used to evaluate the expression and functionality of PAR-2 receptor and to assess the expression of COX-2. COX-2 activity was evaluated with a commercial activity assay kit and by measurement of PGF2α production. Proliferation assays were also performed in presence of different prostaglandins (PGs. Results Tryptase increased L6 myoblast proliferation by 35% above control group and this effect was completely inhibited by APC-366. We confirmed the expression of PAR-2 receptor in vivo in skeletal muscle cells and in satellite cells and in vitro in L6 cells, where PAR-2 was found to be functional. Trypsin and SLIGKV increased L6 cells proliferation by 76% and 26% above control, respectively. COX-2 activity was increased following stimulation with PAR-2 agonist but its expression remained unchanged. Inhibition of COX-2 activity by NS-398 abolished the stimulation of cell proliferation induced by tryptase and trypsin. Finally, 15-deoxy-Δ-12,14-prostaglandin J2 (15Δ-PGJ2, a product of COX-2-derived prostaglandin D2, stimulated myoblast proliferation, but not PGE2 and PGF2α. Conclusions Taken together, our data show that tryptase can stimulate myoblast proliferation and this effect is part of a signaling cascade dependent on PAR-2 activation and on the downstream

  8. Cathepsin B is up-regulated and mediates extracellular matrix degradation in trabecular meshwork cells following phagocytic challenge.

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    Kristine Porter

    Full Text Available Cells in the trabecular meshwork (TM, a tissue responsible for draining aqueous humor out of the eye, are known to be highly phagocytic. Phagocytic activity in TM cells is thought to play an important role in outflow pathway physiology. However, the molecular mechanisms triggered by phagocytosis in TM cells are unknown. Here we investigated the effects of chronic phagocytic stress on lysosomal function using different phagocytic ligands (E. coli, carboxylated beads, collagen I-coated beads, and pigment. Lysotracker red co-localization and electron micrographs showed the maturation of E. coli- and collagen I-coated beads-containing phagosomes into phagolysosomes. Maturation of phagosomes into phagolysosomes was not observed with carboxylated beads or pigment particles. In addition, phagocytosis of E. coli and collagen I-coated beads led to increased lysosomal mass, and the specific up-regulation and activity of cathepsin B (CTSB. Higher levels of membrane-bound and secreted CTSB were also detected. Moreover, in vivo zymography showed the intralysosomal degradation of ECM components associated with active CTSB, as well as an overall increased gelatinolytic activity in phagocytically challenged TM cells. This increased gelatinolytic activity with phagocytosis was partially blocked with an intracellular CTSB inhibitor. Altogether, these results suggest a potential role of phagocytosis in outflow pathway tissue homeostasis through the up-regulation and/or proteolytic activation of extracellular matrix remodeling genes.

  9. Hair follicle stem cell proliferation, Akt and Wnt signaling activation in TPA-induced hair regeneration.

    Science.gov (United States)

    Qiu, Weiming; Lei, Mingxing; Zhou, Ling; Bai, Xiufeng; Lai, Xiangdong; Yu, Yu; Yang, Tian; Lian, Xiaohua

    2017-06-01

    Regeneration of hair follicles relies on activation of hair follicle stem cells during telogen to anagen transition process in hair cycle. This process is rigorously controlled by intrinsic and environmental factors. 12-o-tetradecanoylphorbol-13-acetate (TPA), a tumor promoter, accelerates reentry of hair follicles into anagen phase. However, it is unclear that how TPA promotes the hair regeneration. In the present study, we topically applied TPA onto the dorsal skin of 2-month-old C57BL/6 female mice to examine the activity of hair follicle stem cells and alteration of signaling pathways during hair regeneration. We found that refractory telogen hair follicles entered anagen prematurely after TPA treatment, with the enhanced proliferation of CD34-positive hair follicle stem cells. Meanwhile, we observed Akt signaling was activated in epidermis, hair infundibulum, bulge and hair bulb, and Wnt signaling was also activated after hair follicle stem cells proliferation. Importantly, after overexpression of DKK1, a specific Wnt signaling inhibitor, the accelerated reentry of hair follicles into anagen induced by TPA was abolished. Our data indicated that TPA-induced hair follicle regeneration is associated with activation of Akt and Wnt/β-catenin signaling.

  10. The effect of propylthiouracil on function of phagocytic peripheral blood cells in persons with thyroid hyperfunction

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    Đukić Aleksandar

    2006-01-01

    Full Text Available Introduction. It is known that hyperthyroidism as well as thyrosuppressive therapy can influence the cells of immunological system. Objective. To examine the function of phagocyte cells in persons with hyperthyroidism and to examine if propylthiouracil (PTU influences this function. Method. The study included 15 patients with hyperthyroidism and 10 healthy persons. The parameters of phagocytic activity of mononuclear and polymorphonuclear leucocytes were tested by method of ingestion of particles of inactivated yeast labeled with neutral-red. Results. It was demonstrated that patients with hyperthyroidism, before the onset of therapy as well as 14 days after introduction of PTU, had decreased number of leucocytes (before PTU: 6.7±3.2Ч109/l, after PTU: 6.1±2.0Ч109/l and control: 8.0±1.6Ч109/l; p=0.039, PMN leucocytes (before PTU: 3.9±2,4 Ч109/l, after PTU: 3.5±1.6Ч109/l and control: 4.8±0.9Ч109/l; p=0.037 and number of phagocyte PMN cells (before PTU: 0.9±0.9Ч109/l, after PTU: 0.9±0.7Ч109/l and control: 1.3±0.6 Ч109/l; p<0,05, but they had increased index of phagocytosis (before PTU: 2.0±0.2, after PTU: 1.9±0.2 and control: 1.7±0.2; p=0.029, while capacity of phagocytosis remained unchanged (before PTU: 1.9±1.7Ч109/l, after PTU: 1.6±1.9Ч109/l and control: 2.4±1.4Ч109/l; p>0.05. The number of mononuclear leucocytes and parameters of phagocytic activity of mononuclear phagocytes in persons with hyperthyroidism did not change significantly in comparison with the control group. Conclusion. Patients with hyperthyroidism had decreased number of leucocytes, PMN leucocytes and number of phagocyte PMN cells, and increased index of phagocytosis, while capacity of phagocytosis remained unchanged. The number and parameters of phagocytic activity of mononuclear leucocytes did not change. PTU therapy had no effect on the examined parameters.

  11. FGF8 activates proliferation and migration in mouse post-natal oligodendrocyte progenitor cells.

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    Pablo Cruz-Martinez

    Full Text Available Fibroblast growth factor 8 (FGF8 is a key molecular signal that is necessary for early embryonic development of the central nervous system, quickly disappearing past this point. It is known to be one of the primary morphogenetic signals required for cell fate and survival processes in structures such as the cerebellum, telencephalic and isthmic organizers, while its absence causes severe abnormalities in the nervous system and the embryo usually dies in early stages of development. In this work, we have observed a new possible therapeutic role for this factor in demyelinating disorders, such as leukodystrophy or multiple sclerosis. In vitro, oligodendrocyte progenitor cells were cultured with differentiating medium and in the presence of FGF8. Differentiation and proliferation studies were performed by immunocytochemistry and PCR. Also, migration studies were performed in matrigel cultures, where oligodendrocyte progenitor cells were placed at a certain distance of a FGF8-soaked heparin bead. The results showed that both migration and proliferation was induced by FGF8. Furthermore, a similar effect was observed in an in vivo demyelinating mouse model, where oligodendrocyte progenitor cells were observed migrating towards the FGF8-soaked heparin beads where they were grafted. In conclusion, the results shown here demonstrate that FGF8 is a novel factor to induce oligodendrocyte progenitor cell activation, migration and proliferation in vitro, which can be extrapolated in vivo in demyelinated animal models.

  12. THE EFFECT OF CURCUMIN ON SECRETORY ACTIVITY, PROLIFERATION AND APOPTOSIS OF THE PORCINE OVARIAN GRANULOSA CELLS

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    Attila Kádasi

    2012-08-01

    Full Text Available The aim of this in vitro study was to examine the effect of natural plant (Curcuma longa molecule curcumin on secretory activity, proliferation and apoptosis of porcine granulosa cells. The secretion of steroid hormones (progesterone, testosterone, accumulation of PCNA (marker of proliferation and bax (marker of apoptosis in granulosa cells of swine ovaries after curcumin treatment at the doses 0, 1, 10, 100 μg.mL-1 was determined by RIA and immunocytochemistry. It was observed that, addition of curcumin stimulated progesterone (at doses 1 and 10 μg.mL-1, but not 100 μg.mL-1 and testosterone at (100 μg.mL-1 but not 1 and 10 μg.mL-1 release. The number of cells contained PCNA was down-regulated by curcumin administration (at dose of 10 μg.mL-1, but not of 1 and 100 μg.mL-1. Bax expression was stimulated by curcumin at all doses added. Our results suggest a direct effect of curcumin on ovarian functions: steroidogenesis, proliferation and apoptosis. This could suggest antireproductive properties of curcumin in swine ovaries.

  13. Moderate plasma activated media suppresses proliferation and migration of MDCK epithelial cells

    International Nuclear Information System (INIS)

    Mohades, Soheila; Laroussi, Mounir; Maruthamuthu, Venkat

    2017-01-01

    Low-temperature plasma has been shown to have diverse biomedical uses, including its applications in cancer and wound healing. One recent approach in treating mammalian cells with plasma is through the use of plasma activated media (PAM), which is produced by exposing cell culture media to plasma. While the adverse effects of PAM treatment on cancerous epithelial cell lines have been recently studied, much less is known about the interaction of PAM with normal epithelial cells. In this paper, non-cancerous canine kidney MDCK (Madin-Darby Canine Kidney) epithelial cells were treated by PAM and time-lapse microscopy was used to directly monitor their proliferation and random migration upon treatment. While longer durations of PAM treatment led to cell death, we found that moderate levels of PAM treatment inhibited proliferation in these epithelial cells. We also found that PAM treatment reduced random cell migration within epithelial islands. Immunofluorescence staining showed that while there were no major changes in the actin/adhesion apparatus, there was a significant change in the nuclear localization of proliferation marker Ki-67, consistent with our time-lapse results. (paper)

  14. Low Dose Cadmium Inhibits Proliferation of Human Renal Mesangial Cells via Activation of the JNK Pathway

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    Chen, Xiaocui; Li, Jing; Cheng, Zuowang; Xu, Yinghua; Wang, Xia; Li, Xiaorui; Xu, Dongmei; Kapron, Carolyn M.; Liu, Ju

    2016-01-01

    Cadmium (Cd) is a heavy metal and environmental pollutant. The kidney is the principal target organ of Cd exposure. Previously, we found that low concentration of Cd damages the integrity of the glomerular filtration barrier. However, little is known about the effects of Cd on renal mesangial cells, which provide structural support for the glomerular capillary loops and regulate intraglomerular blood flow. In this study, human renal mesangial cells (HRMCs) were cultured in the presence of serum and treated with 4 μM Cd. We found that Cd activates the c-Jun N-terminal kinase (JNK) pathway, and increases the protein levels of c-Jun and c-Fos. Cd treatment also induces a decrease in proliferation and an increase in apoptosis of HRMCs, but only the decrease in HRMC proliferation was reversed by pretreatment with SP600125, an inhibitor of the JNK pathway. In addition, Cd does not change the expression of α-smooth muscle actin and platelet-derived growth factor receptor-β, the markers of mesangial cells, or the alignment of the filamentous actin (F-actin) cytoskeleton of HRMCs. Our data indicate that the JNK pathway mediates the inhibitory effects of Cd on HRMC proliferation. PMID:27739415

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

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

    2013-01-18

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

  16. Echinococcus multilocularis vesicular fluid inhibits activation and proliferation of natural killer cells.

    Science.gov (United States)

    Bellanger, Anne-Pauline; Mougey, Valentine; Pallandre, Jean-Rene; Gbaguidi-Haore, Houssein; Godet, Yann; Millon, Laurence

    2017-08-25

    Alveolar echinococcosis is a severe chronic helminthic disease that mimics slow-growing liver cancer. The immune evasion strategy of Echinococcus multilocularis Leuckart, 1863 remains poorly understood. The aim of this study was to investigate in vitro the impact of E. multilocularis vesicular fluid (Em-VF) on peripheral blood mononuclear cells (PBMC) and on natural killer (NK) cells. PBMC and NK cells were exposed to Em-VF (1 µg/ml) during six days. The effect of Em-VF was assessed on CD69, viability and proliferation, and on and transforming growth factor β (TGF-β), interferon γ (IFN-γ), interleukin 17 (IL-17) and interleukin 10, using flow cytometry and ELISA, respectively. Exposure to Em-VF had no bearing on PBMC's viability, proliferation and expression of CD69. In contrast, higher levels of IL-17 at day three and of TGF-β at day six were observed in PBMC supernatant after exposure to Em-VF (p Wilcoxon signed-rank test). Exposure to Em-VF induced a significant decrease of CD69 expression of NK cells at day three and a significant decrease of proliferation of NK cells at day six (p Wilcoxon signed-rank test). In contrast, NK cells viability and levels of cytokines did not vary significantly over Em-VF stimulation. Exposure to Em-VF had a significant bearing on activation and proliferation of NK cells. NK cells may play an important role in the immune response of the host against E. multilocularis.

  17. Protease-activated receptor 2 agonist increases cell proliferation and invasion of human pancreatic cancer cells

    Science.gov (United States)

    XIE, LIQUN; DUAN, ZEXING; LIU, CAIJU; ZHENG, YANMIN; ZHOU, JING

    2015-01-01

    The aim of this study was to determine the expression of protease-activated receptor 2 (PAR-2) in the human pancreatic cancer cell line SW1990, and to evaluate its effect on cell proliferation and invasion. The expression of PAR-2 protein and mRNA in SW1990 cells was determined by immunocytochemistry and reverse transcription polymerase chain reaction (PCR), respectively. MTT and cell invasion and migration assays, as well as semi-quantitative PCR and zymography analysis, were additionally performed. PAR-2 mRNA was significantly upregulated in the cells treated with trypsin or the PAR-2 activating peptide Ser-Leu-Ile-Gly-Lys-Val (SLIGKV) (P0.05). Trypsin and SLIGKV significantly promoted SW1990 cell proliferation in a dose- and time-dependent manner (P<0.05). Compared with the control group, trypsin and SLIGKV significantly increased the mRNA expression (P<0.01) and gelatinolytic activity (P<0.01) of matrix metalloproteinase (MMP)-2. In conclusion, PAR-2 is expressed in SW1990 cells. PAR-2 activation may promote the invasion and migration of human pancreatic cancer cells by increasing MMP-2 expression. PMID:25452809

  18. Selective transcription and cellular proliferation induced by PDGF require histone deacetylase activity

    International Nuclear Information System (INIS)

    Catania, Annunziata; Iavarone, Carlo; Carlomagno, Stella M.; Chiariello, Mario

    2006-01-01

    Histone deacetylases (HDACs) are key regulatory enzymes involved in the control of gene expression and their inhibition by specific drugs has been widely correlated to cell cycle arrest, terminal differentiation, and apoptosis. Here, we investigated whether HDAC activity was required for PDGF-dependent signal transduction and cellular proliferation. Exposure of PDGF-stimulated NIH3T3 fibroblasts to the HDAC inhibitor trichostatin A (TSA) potently repressed the expression of a group of genes correlated to PDGF-dependent cellular growth and pro-survival activity. Moreover, we show that TSA interfered with STAT3-dependent transcriptional activity induced by PDGF. Still, neither phosphorylation nor nuclear translocation and DNA-binding in vitro and in vivo of STAT3 were affected by using TSA to interfere with PDGF stimulation. Finally, TSA treatment resulted in the suppression of PDGF-dependent cellular proliferation without affecting cellular survival of NIH3T3 cells. Our data indicate that inhibition of HDAC activity antagonizes the mitogenic effect of PDGF, suggesting that these drugs may specifically act on the expression of STAT-dependent, PDGF-responsive genes

  19. Peroxisome Proliferator-Activated Receptor and Vitamin D Receptor Signaling Pathways in Cancer Cells

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    Yasuko Kitagishi

    2013-10-01

    Full Text Available Peroxisome proliferator-activated receptors (PPARs are members of the superfamily of nuclear hormone receptors, which respond to specific ligands such as polyunsaturated fatty acids by altering gene expression. Three subtypes of this receptor have been discovered, each evolving to achieve different biological functions. Like other nuclear receptors, the transcriptional activity of PPARs is affected not only by ligand-stimulation, but also by cross-talk with other molecules. For example, both PPARs and the RXRs are ligand-activated transcription factors that coordinately regulate gene expression. In addition, PPARs and vitamin D receptor (VDR signaling pathways regulate a multitude of genes that are of importance for cellular functions including cell proliferation and cell differentiation. Interaction of the PPARs and VDR signaling pathways has been shown at the level of molecular cross-regulation of their transcription factor. A variety of ligands influencing the PPARs and VDR signaling pathways have been shown to reveal chemopreventive potential by mediating tumor suppressive activities in human cancers. Use of these compounds may represent a potential novel strategy to prevent cancers. This review summarizes the roles of the PPARs and the VDR in pathogenesis and progression of cancer.

  20. Peroxisome Proliferator-Activated Receptor and Vitamin D Receptor Signaling Pathways in Cancer Cells

    Energy Technology Data Exchange (ETDEWEB)

    Matsuda, Satoru, E-mail: smatsuda@cc.nara-wu.ac.jp; Kitagishi, Yasuko [Department of Food Science and Nutrition, Nara Women’s University, Kita-Uoya Nishimachi, Nara 630-8506 (Japan)

    2013-10-21

    Peroxisome proliferator-activated receptors (PPARs) are members of the superfamily of nuclear hormone receptors, which respond to specific ligands such as polyunsaturated fatty acids by altering gene expression. Three subtypes of this receptor have been discovered, each evolving to achieve different biological functions. Like other nuclear receptors, the transcriptional activity of PPARs is affected not only by ligand-stimulation, but also by cross-talk with other molecules. For example, both PPARs and the RXRs are ligand-activated transcription factors that coordinately regulate gene expression. In addition, PPARs and vitamin D receptor (VDR) signaling pathways regulate a multitude of genes that are of importance for cellular functions including cell proliferation and cell differentiation. Interaction of the PPARs and VDR signaling pathways has been shown at the level of molecular cross-regulation of their transcription factor. A variety of ligands influencing the PPARs and VDR signaling pathways have been shown to reveal chemopreventive potential by mediating tumor suppressive activities in human cancers. Use of these compounds may represent a potential novel strategy to prevent cancers. This review summarizes the roles of the PPARs and the VDR in pathogenesis and progression of cancer.

  1. Peroxisome Proliferator-Activated Receptor and Vitamin D Receptor Signaling Pathways in Cancer Cells

    International Nuclear Information System (INIS)

    Matsuda, Satoru; Kitagishi, Yasuko

    2013-01-01

    Peroxisome proliferator-activated receptors (PPARs) are members of the superfamily of nuclear hormone receptors, which respond to specific ligands such as polyunsaturated fatty acids by altering gene expression. Three subtypes of this receptor have been discovered, each evolving to achieve different biological functions. Like other nuclear receptors, the transcriptional activity of PPARs is affected not only by ligand-stimulation, but also by cross-talk with other molecules. For example, both PPARs and the RXRs are ligand-activated transcription factors that coordinately regulate gene expression. In addition, PPARs and vitamin D receptor (VDR) signaling pathways regulate a multitude of genes that are of importance for cellular functions including cell proliferation and cell differentiation. Interaction of the PPARs and VDR signaling pathways has been shown at the level of molecular cross-regulation of their transcription factor. A variety of ligands influencing the PPARs and VDR signaling pathways have been shown to reveal chemopreventive potential by mediating tumor suppressive activities in human cancers. Use of these compounds may represent a potential novel strategy to prevent cancers. This review summarizes the roles of the PPARs and the VDR in pathogenesis and progression of cancer

  2. Independent Activation of Hepatitis B Virus Biosynthesis by Retinoids, Peroxisome Proliferators, and Bile Acids

    Science.gov (United States)

    Reese, Vanessa C.; Oropeza, Claudia E.

    2013-01-01

    In the human hepatoma cell line HepG2, retinoic acid, clofibric acid, and bile acid treatment can only modestly increase hepatitis B virus (HBV) biosynthesis. Utilizing the human embryonic kidney cell line 293T, it was possible to demonstrate that the retinoid X receptor α (RXRα) plus its ligand can support viral biosynthesis independently of additional nuclear receptors. In addition, RXRα/peroxisome proliferator-activated receptor α (PPARα) and RXRα/farnesoid X receptor α (FXRα) heterodimeric nuclear receptors can also mediate ligand-dependent HBV transcription and replication when activated by clofibric acid and bile acid, respectively, independently of a requirement for the ligand-dependent activation of RXRα. These observations indicate that there are at least three possible modes of ligand-mediated activation of HBV transcription and replication existing within hepatocytes, suggesting that multiple independent mechanisms control viral production in the livers of infected individuals. PMID:23135717

  3. Meclozine facilitates proliferation and differentiation of chondrocytes by attenuating abnormally activated FGFR3 signaling in achondroplasia.

    Directory of Open Access Journals (Sweden)

    Masaki Matsushita

    Full Text Available Achondroplasia (ACH is one of the most common skeletal dysplasias with short stature caused by gain-of-function mutations in FGFR3 encoding the fibroblast growth factor receptor 3. We used the drug repositioning strategy to identify an FDA-approved drug that suppresses abnormally activated FGFR3 signaling in ACH. We found that meclozine, an anti-histamine drug that has long been used for motion sickness, facilitates chondrocyte proliferation and mitigates loss of extracellular matrix in FGF2-treated rat chondrosarcoma (RCS cells. Meclozine also ameliorated abnormally suppressed proliferation of human chondrosarcoma (HCS-2/8 cells that were infected with lentivirus expressing constitutively active mutants of FGFR3-K650E causing thanatophoric dysplasia, FGFR3-K650M causing SADDAN, and FGFR3-G380R causing ACH. Similarly, meclozine alleviated abnormally suppressed differentiation of ATDC5 chondrogenic cells expressing FGFR3-K650E and -G380R in micromass culture. We also confirmed that meclozine alleviates FGF2-mediated longitudinal growth inhibition of embryonic tibia in bone explant culture. Interestingly, meclozine enhanced growth of embryonic tibia in explant culture even in the absence of FGF2 treatment. Analyses of intracellular FGFR3 signaling disclosed that meclozine downregulates phosphorylation of ERK but not of MEK in FGF2-treated RCS cells. Similarly, meclozine enhanced proliferation of RCS cells expressing constitutively active mutants of MEK and RAF but not of ERK, which suggests that meclozine downregulates the FGFR3 signaling by possibly attenuating ERK phosphorylation. We used the C-natriuretic peptide (CNP as a potent inhibitor of the FGFR3 signaling throughout our experiments, and found that meclozine was as efficient as CNP in attenuating the abnormal FGFR3 signaling. We propose that meclozine is a potential therapeutic agent for treating ACH and other FGFR3-related skeletal dysplasias.

  4. Meclozine Facilitates Proliferation and Differentiation of Chondrocytes by Attenuating Abnormally Activated FGFR3 Signaling in Achondroplasia

    Science.gov (United States)

    Matsushita, Masaki; Kitoh, Hiroshi; Ohkawara, Bisei; Mishima, Kenichi; Kaneko, Hiroshi; Ito, Mikako; Masuda, Akio; Ishiguro, Naoki; Ohno, Kinji

    2013-01-01

    Achondroplasia (ACH) is one of the most common skeletal dysplasias with short stature caused by gain-of-function mutations in FGFR3 encoding the fibroblast growth factor receptor 3. We used the drug repositioning strategy to identify an FDA-approved drug that suppresses abnormally activated FGFR3 signaling in ACH. We found that meclozine, an anti-histamine drug that has long been used for motion sickness, facilitates chondrocyte proliferation and mitigates loss of extracellular matrix in FGF2-treated rat chondrosarcoma (RCS) cells. Meclozine also ameliorated abnormally suppressed proliferation of human chondrosarcoma (HCS-2/8) cells that were infected with lentivirus expressing constitutively active mutants of FGFR3-K650E causing thanatophoric dysplasia, FGFR3-K650M causing SADDAN, and FGFR3-G380R causing ACH. Similarly, meclozine alleviated abnormally suppressed differentiation of ATDC5 chondrogenic cells expressing FGFR3-K650E and -G380R in micromass culture. We also confirmed that meclozine alleviates FGF2-mediated longitudinal growth inhibition of embryonic tibia in bone explant culture. Interestingly, meclozine enhanced growth of embryonic tibia in explant culture even in the absence of FGF2 treatment. Analyses of intracellular FGFR3 signaling disclosed that meclozine downregulates phosphorylation of ERK but not of MEK in FGF2-treated RCS cells. Similarly, meclozine enhanced proliferation of RCS cells expressing constitutively active mutants of MEK and RAF but not of ERK, which suggests that meclozine downregulates the FGFR3 signaling by possibly attenuating ERK phosphorylation. We used the C-natriuretic peptide (CNP) as a potent inhibitor of the FGFR3 signaling throughout our experiments, and found that meclozine was as efficient as CNP in attenuating the abnormal FGFR3 signaling. We propose that meclozine is a potential therapeutic agent for treating ACH and other FGFR3-related skeletal dysplasias. PMID:24324705

  5. Peroxisome Proliferator-Activated Receptors and Hepatitis C Virus-Induced Insulin Resistance

    Directory of Open Access Journals (Sweden)

    Francesco Negro

    2009-01-01

    Full Text Available Insulin resistance and type 2 diabetes are associated with hepatitis C virus infection. A wealth of clinical and experimental data suggests that the virus is directly interfering with the insulin signalling in hepatocytes. In the case of at least one viral genotype (the type 3a, insulin resistance seems to be directly mediated by the downregulation of the peroxisome proliferator-activated receptor γ. Whether and how this interaction may be manipulated pharmacologically, in order to improve the responsiveness to antivirals of insulin resistant chronic hepatitis C, patients remain to be fully explored.

  6. Stimulation of murine stem cell proliferation by circulating activities produced during the recovery of a radiation-induced hemopoietic injury

    International Nuclear Information System (INIS)

    Grande Azanedo, M.T.

    1988-01-01

    The proliferative activity of CFU-S, low in normal steady state, increases after treatment with different aggressors, i.e. radiation. This stimulation has been attributed in part to a local regulation system of stem cell proliferation, and at least in part to a humoral regulatory system. In the present work it has been investigated the role that circulating activities have in the CFU- S stimulation, by means of in vitro and in vivo incubation assays with diffusion chambers. The results show that bone marrow of mice irradiated with 5 Gy produces in vitro diffusible activities capable of stimulating the CFU-S proliferation. As well with this same dose circulating activities are also produced in vivo. In addition we have observed that these activities are only released during the periods of active hemopoietic regeneration that follow irradiation with moderate doses (1.5 and 5 Gy). In another set of experiments we saw that the stimulating activities are also detected in serum of mice irradiated with 5 Gy. These serum activities modify the proliferative state of very primitive precursors (12 d CFU-S). When the serum activities are added to long term bone marrow cultures the CFU-S) are also stimulated to proliferate. Finally, we observed that the radiation-induced serum activities stimulate the proliferation of bone marrow CFU-S when injected into normal mice, suggesting that such activities are involved in the regulation of CFU-S proliferation. (Author)

  7. Adenosine: an activity-dependent axonal signal regulating MAP kinase and proliferation in developing Schwann cells.

    Science.gov (United States)

    Stevens, Beth; Ishibashi, Tomoko; Chen, Jiang-Fan; Fields, R Douglas

    2004-02-01

    Nonsynaptic release of ATP from electrically stimulated dorsal root gangion (DRG) axons inhibits Schwann cell (SC) proliferation and arrests SC development at the premyelinating stage, but the specific types of purinergic receptor(s) and intracellular signaling pathways involved in this form of neuron-glia communication are not known. Recent research shows that adenosine is a neuron-glial transmitter between axons and myelinating glia of the CNS. The present study investigates the possibility that adenosine might have a similar function in communicating between axons and premyelinating SCs. Using a combination of pharmacological and molecular approaches, we found that mouse SCs in culture express functional adenosine receptors and ATP receptors, a far more complex array of purinergic receptors than thought previously. Adenosine, but not ATP, activates ERK/MAPK through stimulation of cAMP-linked A2(A) adenosine receptors. Both ATP and adenosine inhibit proliferation of SCs induced by platelet-derived growth factor (PDGF), via mechanisms that are partly independent. In contrast to ATP, adenosine failed to inhibit the differentiation of SCs to the O4+ stage. This indicates that, in addition to ATP, adenosine is an activity-dependent signaling molecule between axons and premyelinating Schwann cells, but that electrical activity, acting through adenosine, has opposite effects on the differentiation of myelinating glia in the PNS and CNS.

  8. Atf4 regulates chondrocyte proliferation and differentiation during endochondral ossification by activating Ihh transcription.

    Science.gov (United States)

    Wang, Weiguang; Lian, Na; Li, Lingzhen; Moss, Heather E; Wang, Weixi; Perrien, Daniel S; Elefteriou, Florent; Yang, Xiangli

    2009-12-01

    Activating transcription factor 4 (Atf4) is a leucine-zipper-containing protein of the cAMP response element-binding protein (CREB) family. Ablation of Atf4 (Atf4(-/-)) in mice leads to severe skeletal defects, including delayed ossification and low bone mass, short stature and short limbs. Atf4 is expressed in proliferative and prehypertrophic growth plate chondrocytes, suggesting an autonomous function of Atf4 in chondrocytes during endochondral ossification. In Atf4(-/-) growth plate, the typical columnar structure of proliferative chondrocytes is disturbed. The proliferative zone is shortened, whereas the hypertrophic zone is transiently expanded. The expression of Indian hedgehog (Ihh) is markedly decreased, whereas the expression of other chondrocyte marker genes, such as type II collagen (Col2a1), PTH/PTHrP receptor (Pth1r) and type X collagen (Col10a1), is normal. Furthermore, forced expression of Atf4 in chondrocytes induces endogenous Ihh mRNA, and Atf4 directly binds to the Ihh promoter and activates its transcription. Supporting these findings, reactivation of Hh signaling pharmacologically in mouse limb explants corrects the Atf4(-/-) chondrocyte proliferation and short limb phenotypes. This study thus identifies Atf4 as a novel transcriptional activator of Ihh in chondrocytes that paces longitudinal bone growth by controlling growth plate chondrocyte proliferation and differentiation.

  9. Human retinal pigment epithelial cells inhibit proliferation and IL2R expression of activated T cells

    DEFF Research Database (Denmark)

    Kaestel, Charlotte G; Jørgensen, Annette; Nielsen, Mette

    2002-01-01

    -Thymidine incorporation assay, respectively. T cells and RPE cells were cultured directly together or in a transwell system for determination of the effect of cell contact. The importance of cell surface molecules was examined by application of a panel of blocking antibodies (CD2, CD18, CD40, CD40L, CD54, CD58......) in addition to use of TCR negative T cell lines. The expression of IL2R-alpha -beta and -gamma chains of activated T cells was analysed by flow cytometry after incubation of T cells alone or with RPE cells. Human RPE cells were found to inhibit the proliferation of activated T cells by a cell contact......-beta and -gamma chain expression within 24 hr after removal from the coculture. It is concluded that the cultured human adult and foetal RPE cells inhibit the proliferation of activated T cells by a process that does not involve apoptosis. It depends on cell contact but the involved surface molecules were...

  10. Persistent STAT3 Activation in Colon Cancer Is Associated with Enhanced Cell Proliferation and Tumor Growth

    Directory of Open Access Journals (Sweden)

    Florian M. Corvinus

    2005-06-01

    Full Text Available Colorectal carcinoma (CRC is a major cause of morbidity and mortality in Western countries. It has so far been molecularly defined mainly by alterations of the Wnt pathway. We show here for the first time that aberrant activities of the signal transducer and activator of transcription STAT3 actively contribute to this malignancy and, thus, are a potential therapeutic target for CRC. Constitutive STAT3 activity was found to be abundant in dedifferentiated cancer cells and infiltrating lymphocytes of CRC samples, but not in non-neoplastic colon epithelium. Cell lines derived from malignant colorectal tumors lost persistent STAT3 activity in culture. However, implantation of colon carcinoma cells into nude mice resulted in restoration of STAT3 activity, suggesting a role of an extracellular stimulus within the tumor microenvironment as a trigger for STAT activation. STAT3 activity in CRC cells triggered through interleukin-6 or through a constitutively active STAT3 mutant promoted cancer cell multiplication, whereas STAT3 inhibition through a dominant-negative variant impaired IL-6-driven proliferation. Blockade of STAT3 activation in CRCderived xenograft tumors slowed down their development, arguing for a contribution of STAT3 to colorectal tumor growth.

  11. Transcriptional Control of Vascular Smooth Muscle Cell Proliferation by Peroxisome Proliferator-Activated Receptor-γ: Therapeutic Implications for Cardiovascular Diseases

    Directory of Open Access Journals (Sweden)

    Florence Gizard

    2008-01-01

    Full Text Available Proliferation of vascular smooth muscle cells (SMCs is a critical process for the development of atherosclerosis and complications of procedures used to treat atherosclerotic diseases, including postangioplasty restenosis, vein graft failure, and transplant vasculopathy. Peroxisome proliferator-activated receptor (PPAR γ is a member of the nuclear hormone receptor superfamily and the molecular target for the thiazolidinediones (TZD, used clinically to treat insulin resistance in patients with type 2 diabetes. In addition to their efficacy to improve insulin sensitivity, TZD exert a broad spectrum of pleiotropic beneficial effects on vascular gene expression programs. In SMCs, PPARγ is prominently upregulated during neointima formation and suppresses the proliferative response to injury of the arterial wall. Among the molecular target genes regulated by PPARγ in SMCs are genes encoding proteins involved in the regulation of cell-cycle progression, cellular senescence, and apoptosis. This inhibition of SMC proliferation is likely to contribute to the prevention of atherosclerosis and postangioplasty restenosis observed in animal models and proof-of-concept clinical studies. This review will summarize the transcriptional target genes regulated by PPARγ in SMCs and outline the therapeutic implications of PPARγ activation for the treatment and prevention of atherosclerosis and its complications.

  12. MAGE-A1 promotes melanoma proliferation and migration through C-JUN activation

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Dong [Department of Dermatology, General Hospital of People' s Liberation Army, Beijing 100853 (China); The 309th Hospital of China People' s Liberation Army, Beijing 100091 (China); Wang, Junyun; Ding, Nan [CAS Key Laboratory of Genome Sciences and Information, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing 100101 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Li, Yongjun; Yang, Yaran [CAS Key Laboratory of Genome Sciences and Information, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing 100101 (China); Fang, Xiangdong, E-mail: fangxd@big.ac.cn [CAS Key Laboratory of Genome Sciences and Information, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing 100101 (China); Zhao, Hua, E-mail: luckhua301@163.com [Department of Dermatology, General Hospital of People' s Liberation Army, Beijing 100853 (China)

    2016-05-13

    MAGE-A1 belongs to the chromosome X-clustered genes of cancer-testis antigen family and is normally expressed in the human germ line but is also overexpressed in various tumors. Previous studies of MAGE-A1 in melanoma mainly focused on methylation changes or its role in immunotherapy, however, its biological functions in melanoma have remained unknown. In order to determine the role of MAGE-A1 in melanoma growth and metastasis, we manipulated melanoma cell lines with overexpression and knockdown of MAGE-A1. Integration of cell proliferation assays, transwell migration and invasion assays, and RNA-Seq analysis revealed that up-regulation of MAGE-A1 dramatically promoted proliferation, migration, and invasion of human melanoma cell lines in vitro, while down-regulation of MAGE-A1 inhibited those characteristics associated with tumor cells. Furthermore, transcriptome sequencing revealed that MAGE-A1 exerts its tumor promoting activity by activating p-C-JUN directly or through ERK-MAPK signaling pathways. Based on our findings, we propose that MAGE-A1 may be a potential therapeutic target for melanoma patients. - Highlights: • MAGE-A1 promotes proliferation and clone formation in melanoma cell lines. • MAGE-A1 enhances tumor cell migration and invasion in melanoma cell lines. • Network including C-JUN, IL8, and ARHGAP29 play critical role in malignant melanoma. • Oncogenic MAGE-A1 increases p-C-JUN levels, possibly via ERK-MAPK signaling pathway.

  13. Activities of the study group of peaceful uses of nuclear energy and non-proliferation policy. FY Heisei 11

    International Nuclear Information System (INIS)

    Kurosawa, Mitsuru; Oi, Noboru

    2000-01-01

    The Study Group on the Peaceful Uses of Nuclear Energy and Non-Proliferation Policy (Chairman: Prof. Kurosawa) was established in FY1999 with the funding from the Science and Technology Agency. The aim of the Study Group is to clearly understand nuclear proliferation issues and to lead international opinion. Nuclear non-proliferation is a matter of rather scanty interest compared to nuclear safety while both of them are important in promoting peaceful uses of nuclear energy in Japan. In FY2000, the Study Group held International Symposium 'Peaceful Uses of Nuclear Energy and Non-Proliferation: A Challenge of 21st Century' and in conjunction with this Symposium, dispatched 'The Statement on the Peaceful Uses of Nuclear Energy and Non-Proliferation, Action Plan towards 21st Century'. The Statement consists of five propositions: 1) Strengthening the global nuclear non-proliferation regime and making it universally applicable, 2) Negative legacy of cold war: rapid solution of problems, 3) Civil (non-military) plutonium, 4) Development of technology to strengthen the nuclear non-proliferation regime internationally, and 5) Strengthening Japanese initiative on nuclear non-proliferation policy. In this report, these activities will be explained in detail. (author)

  14. Nicotine enhances proliferation, migration, and radioresistance of human malignant glioma cells through EGFR activation

    International Nuclear Information System (INIS)

    Khalil, A.A.; Jameson, M.J.; Broaddus, W.C.; Lin, P.S.; Chung, T.D.

    2013-01-01

    It has been suggested that continued tobacco use during radiation therapy contributes to maintenance of neoplastic growth despite treatment with radiation. Nicotine is a cigarette component that is an established risk factor for many diseases, neoplastic and otherwise. The hypothesis of this work is that nicotine promotes the proliferation, migration, and radioresistance of human malignant glioma cells. The effect of nicotine on cellular proliferation, migration, signaling, and radiation sensitivity were evaluated for malignant glioma U87 and GBM12 cells by use of the AlamarBlue, scratch healing, and clonogenic survival assays. Signal transduction was assessed by immunoblotting for activated EGFR, extracellular regulated kinase (ERK), and AKT. At concentrations comparable with those found in chronic smokers, nicotine induced malignant glioma cell migration, growth, colony formation, and radioresistance. Nicotine increased phosphorylation of EGFR tyr992 , AKT ser473 , and ERK. These molecular effects were reduced by pharmacological inhibitors of EGFR, PI3K, and MEK. It was therefore concluded that nicotine stimulates the malignant behavior of glioma cells in vitro by activation of the EGFR and downstream AKT and ERK pathways. (author)

  15. Expression of Peroxisomes-Proliferate Activated Receptors-γ in Diabetics, Obese and Normal Subjects

    International Nuclear Information System (INIS)

    Afzal, N.

    2016-01-01

    Background: Current research in type 2 diabetes mellitus focuses on the role of Peroxisome-Proliferator Activated Receptors (PPARs) in the pathogenesis of the Insulin Resistance Syndrome (IRS), which are pre-diabetic lesion and the hallmark of fully developed type 2 diabetes mellitus. This study aims at identifying the abnormal status of the PPAR-g in adipose tissues of type 2 diabetes mellitus patients, when compared with matched normal controls. Methods: This cross-sectional study was conducted in Ayub Medical College, Abbottabad, from 2012 to 2014. Sample included three equal groups of patients. Group-1 with diagnosed type 2 diabetes mellitus, aged 40-65 years, acting as the test group, Group-2 included non-diabetic obese, and Group-3 with normal subjects. Transcription Factor Assay for Peroxisome Proliferator Activated Receptor Gamma (gamma PPAR) was done on ELISA Technique from Nuclear Extract procured from Adipose Tissue of the subjects. Results: Mean age of enrolled participants was 48.93 SD±6.52.years. Patients ranged between ages of 40 years to 67 years. The mean values of PPAR in normal, obese and diabetic group were 1.72 SD±0.28, 1.282 SE±0.18 and 1.283 SE±0.18 respectively. The difference in mean values of PPAR was significant ρ<0.05. Conclusion: The levels of PPAR-g in patients with type 2 Diabetes Mellitus and Obese cases are significantly lower than normal controls. (author)

  16. A radiolabel release microassay for phagocytic killing of Candida albicans

    International Nuclear Information System (INIS)

    Bistoni, F.; Baccarini, M.; Blasi, E.; Marconi, P.; Puccetti, P.

    1982-01-01

    The chromium-51 release technique for quantifying intracellular killing of radiolabelled Candida albicans particles was exploited in a microassay in which murine and human phagocytes acted as effectors under peculiarly simple conditions. At appropriate effector: target ratios and with a 4 h incubation, up to 50% specific chromium release could be detected in the supernatant with no need for opsonization or lysis of phagocytes. This simple microassay permits easy-to-perform, simultaneous testing of a variety of different phagocytes even if only available in limited amounts, and provides an objective measurement of intracellular killing of Candida albicans. (Auth.)

  17. Iron inhibits respiratory burst of peritoneal phagocytes in vitro

    DEFF Research Database (Denmark)

    Gotfryd, Kamil; Jurek, Aleksandra; Kubit, Piotr

    2011-01-01

    Objective. This study examines the effects of iron ions Fe(3+) on the respiratory burst of phagocytes isolated from peritoneal effluents of continuous ambulatory peritoneal dialysis (CAPD) patients, as an in vitro model of iron overload in end-stage renal disease (ESRD). Material and Methods....... Respiratory burst of peritoneal phagocytes was measured by chemiluminescence method. Results. At the highest used concentration of iron ions Fe(3+) (100 µM), free radicals production by peritoneal phagocytes was reduced by 90% compared to control. Conclusions. Iron overload may increase the risk of infectious...

  18. Sonic hedgehog stimulates glycolysis and proliferation of breast cancer cells: Modulation of PFKFB3 activation

    International Nuclear Information System (INIS)

    Ge, Xin; Lyu, Pengwei; Gu, Yuanting; Li, Lin; Li, Jingruo; Wang, Yan; Zhang, Linfeng; Fu, Chao; Cao, Zhang

    2015-01-01

    Sonic hesgehog (Shh) signaling has been reported to play an essential role in cancer progression. The mechanism of Shh involved in breast cancer carcinogenesis remains unclear. The present study sought to explore whether Shh signaling could regulate the glycolytic metabolism in breast cancers. Overexpression of the smoothed (Smo) and Gli-1 was found in human primary breast cancers. The expressions of Shh and Gli-1 correlated significantly with tumor size and tumor stage. In vitro, human recombinant Shh (rShh) triggered Smo and Gli-1 expression, promoted glucose utilization and lactate production, and accelerated cell proliferation in MCF-7 and MDA-MB-231 cells. Notably, rShh did not alter 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase 3 (PFKFB3) expression but augmented PFKFB3 phosphorylation on ser 461 , along with elevated fructose-2,6-bisphosphate (F2,6BP) generation by MCF-7 and MDA-MB-231 cells. This effect could be dampened by Smo siRNA but not by Gli-1 siRNA. In addition, our data showed the upregulated expressions of MAPK by rShh and elevatory PFKFB3 phosphorylation by p38/MAPK activated kinase (MK2). In conclusion, our study characterized a novel role of Shh in promoting glycolysis and proliferation of breast cancer cells via PFKFB3 phosphorylation, which was mediated by Smo and p38/MK2. - Highlights: • Overexpression of Smo and Gli-1 was found in human primary breast cancers. • Shh promoted glucose utilization, lactate production, and cell proliferation. • Shh did not alter PFKFB3 expression but augmented PFKFB3 phosphorylation on ser461. • Shh acts on PFKFB3 phosphorylation via Smo and p38 MAPK/MK2

  19. Sonic hedgehog stimulates glycolysis and proliferation of breast cancer cells: Modulation of PFKFB3 activation

    Energy Technology Data Exchange (ETDEWEB)

    Ge, Xin; Lyu, Pengwei; Gu, Yuanting; Li, Lin; Li, Jingruo; Wang, Yan; Zhang, Linfeng [Department of Breast Surgery, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, Henan (China); Fu, Chao [Department of Ultrasonography, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, Henan (China); Cao, Zhang, E-mail: zzzhangcao@126.com [Department of Breast Surgery, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, Henan (China)

    2015-08-28

    Sonic hesgehog (Shh) signaling has been reported to play an essential role in cancer progression. The mechanism of Shh involved in breast cancer carcinogenesis remains unclear. The present study sought to explore whether Shh signaling could regulate the glycolytic metabolism in breast cancers. Overexpression of the smoothed (Smo) and Gli-1 was found in human primary breast cancers. The expressions of Shh and Gli-1 correlated significantly with tumor size and tumor stage. In vitro, human recombinant Shh (rShh) triggered Smo and Gli-1 expression, promoted glucose utilization and lactate production, and accelerated cell proliferation in MCF-7 and MDA-MB-231 cells. Notably, rShh did not alter 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase 3 (PFKFB3) expression but augmented PFKFB3 phosphorylation on ser{sup 461}, along with elevated fructose-2,6-bisphosphate (F2,6BP) generation by MCF-7 and MDA-MB-231 cells. This effect could be dampened by Smo siRNA but not by Gli-1 siRNA. In addition, our data showed the upregulated expressions of MAPK by rShh and elevatory PFKFB3 phosphorylation by p38/MAPK activated kinase (MK2). In conclusion, our study characterized a novel role of Shh in promoting glycolysis and proliferation of breast cancer cells via PFKFB3 phosphorylation, which was mediated by Smo and p38/MK2. - Highlights: • Overexpression of Smo and Gli-1 was found in human primary breast cancers. • Shh promoted glucose utilization, lactate production, and cell proliferation. • Shh did not alter PFKFB3 expression but augmented PFKFB3 phosphorylation on ser461. • Shh acts on PFKFB3 phosphorylation via Smo and p38 MAPK/MK2.

  20. Peroxisome proliferator-activated receptor gamma signaling in human sperm physiology.

    Science.gov (United States)

    Liu, Li-Li; Xian, Hua; Cao, Jing-Chen; Zhang, Chong; Zhang, Yong-Hui; Chen, Miao-Miao; Qian, Yi; Jiang, Ming

    2015-01-01

    Peroxisome proliferator-activated receptor gamma (PPARγ) is a member of the PPARs, which are transcription factors of the steroid receptor superfamily. PPARγ acts as an important molecule for regulating energy homeostasis, modulates the hypothalamic-pituitary-gonadal (HPG) axis, and is reciprocally regulated by HPG. In the human, PPARγ protein is highly expressed in ejaculated spermatozoa, implying a possible role of PPARγ signaling in regulating sperm energy dissipation. PPARγ protein is also expressed in Sertoli cells and germ cells (spermatocytes). Its activation can be induced during capacitation and the acrosome reaction. This mini-review will focus on how PPARγ signaling may affect fertility and sperm quality and the potential reversibility of these adverse effects.

  1. Role of Peroxisome Proliferator-Activated Receptor γ in Ocular Diseases

    Directory of Open Access Journals (Sweden)

    Su Zhang

    2015-01-01

    Full Text Available Peroxisome proliferator-activated receptor γ (PPAR γ, a member of the nuclear receptor superfamily, is a ligand-activated transcription factor that plays an important role in the control of a variety of physiological processes. The last decade has witnessed an increasing interest for the role played by the agonists of PPAR γ in antiangiogenesis, antifibrosis, anti-inflammation effects and in controlling oxidative stress response in various organs. As the pathologic mechanisms of major blinding diseases, such as age-related macular degeneration (AMD, diabetic retinopathy (DR, keratitis, and optic neuropathy, often involve neoangiogenesis and inflammation- and oxidative stress-mediated cell death, evidences are accumulating on the potential benefits of PPAR γ to improve or prevent these vision threatening eye diseases. In this paper we describe what is known about the role of PPAR γ in the ocular pathophysiological processes and PPAR γ agonists as novel adjuvants in the treatment of eye diseases.

  2. Recombinant interleukin 2 stimulates in vivo proliferation of adoptively transferred lymphokine-activated killer (LAK) cells

    International Nuclear Information System (INIS)

    Ettinghausen, S.E.; Lipford, E.H. III; Mule, J.J.; Rosenberg, S.A.

    1985-01-01

    The authors previously reported that the adoptive transfer of lymphokine-activated killer (LAK) cells plus repetitive injections of recombinant interleukin 2 (IL 2) produced a marked reduction in established pulmonary metastases from a variety of murine sarcomas. The requirement for the exogenous administration of IL 2 prompted a subsequent examination of the role of IL 2 in the in vivo function of transferred LAK cells. The in vivo proliferation and migration patterns of lymphoid cells in C57BL/6 mice were examined after i.v. transfer of LAK cells alone, i.p. injection of IL 2 alone, or the combination of LAK cells and IL 2. A model for in vivo labeling of the DNA of dividing cells was used in which mice were injected with 5-[ 125 I]-iodo-2'-deoxyuridine ( 125 IUdR) and, 20 hr later, their tissues were removed and were counted in a gamma analyzer. A proliferation index (PI) was calculated by dividing the mean cpm of organs of experimentally treated mice by the mean cpm of organs of control mice. In animals given LAK cells alone, the lungs and liver demonstrated little if any uptake of 125 IUdR above saline-treated controls, whereas the same organs of mice receiving 6000 U of IL 2 alone displayed higher radiolabel incorporation. When mice were given LAK cells plus 6000 U of IL 2, their tissues showed an additional increase in 125 IUdR uptake

  3. Activation of retinal stem cells in the proliferating marginal region of RCS rats during development of retinitis pigmentosa.

    Science.gov (United States)

    Jian, Qian; Xu, Haiwei; Xie, Hanping; Tian, Chunyu; Zhao, Tongtao; Yin, ZhengQin

    2009-11-06

    Retinal stem cells (RSCs) have been demonstrated at the proliferating marginal regions from the pars plana of ciliary body to the ciliary marginal zone (CMZ) in adult lower vertebrates and mammals. Investigations in the lower vertebrates have provided some evidence that RSCs can proliferate following retinal damage; however, the evidence that this occurs in mammals is not clear. In this study, we explored RSCs proliferation potential of adult mammalian in proliferating marginal regions of Royal College of Surgeons (RCS) rats, an animal model for retinitis pigmentosa (RP). The proliferation was evaluated using BrdU labeling, and Chx-10 as markers to discern progenitor cell of CMZ in Long-Evan's and RCS rats at different postnatal day (PND) after eye opening. We found that few Chx-10 and BrdU labeled cells in the proliferating marginal regions of Long-Evan's rats, which significantly increased in RCS rats at PND30 and PND60. Consistent with this, Chx-10/Vimentin double staining cells in the center retina of RCS rats increased significantly at PND30 after eye opening. In addition, mRNA expression of Shh, Ptch1 and Smo was up-regulated in RCS rats at PND60 compared to age-matched Long-Evan's rats, which revealed Shh/ptc pathway involving in the activation of RSCs. These results suggest that RSCs in the mammalian retinal proliferating marginal regions has the potential to regenerate following degeneration.

  4. Comparison of the effect of activated or non-activated PRP in various concentrations on osteoblast and fibroblast cell line proliferation.

    Science.gov (United States)

    Vahabi, Surena; Yadegari, Zahra; Mohammad-Rahimi, Hossein

    2017-09-01

    Platelet-rich plasma (PRP) contains growth factors which positively affect cell proliferation, cell differentiation, chemotaxis and intracellular matrix synthesis. All these processes are involved in wound healing and tissue regeneration; thus, PRP as a source of growth factors can be used in periodontal regenerative therapies. The purpose of the present study was to assess the effect of various concentrations of activated and non-activated PRP on proliferation of osteoblasts and fibroblasts in vitro. PRP was obtained from three healthy volunteers. 75, 50, 25, and 10% concentrations of f PRP were prepared by dilution in Dulbecco's modified Eagle's medium. In activated PRP groups, PRP concentrations were activated by adding calcium gluconate. Human gingival fibroblast (HGF) cell line and MG-63 (osteosarcoma) human osteoblast-like cell line were used in the study. The MTT proliferation assay was used to assess the effect of different types of PRP concentrates on proliferation of HGF and MG-63 cells, in 24, 48 and 72 h. After 24, 48, and 72 h, the proliferation rate of both cell lines was higher in the positive control group, except in 72 h in HGF cell lines, that 10% non-activated PRP group and 10 and 25% activated PRP groups has higher proliferation rate than the positive control group, which it was not significant. Proliferation rate in cells with 10% activated PRP was highest among samples containing PRP. The current study failed to show the significant effect of activated or non-activated PRP on proliferation of HGFs or MG-63 osteoblast-like cells. However, our results showed that activated PRP had a greater effect than non-activated PRP.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2016-01-29

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

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

    International Nuclear Information System (INIS)

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

    2016-01-01

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

  7. Ligand activation of peroxisome proliferator-activated receptor-β/δ suppresses liver tumorigenesis in hepatitis B transgenic mice

    International Nuclear Information System (INIS)

    Balandaram, Gayathri; Kramer, Lance R.; Kang, Boo-Hyon; Murray, Iain A.; Perdew, Gary H.; Gonzalez, Frank J.; Peters, Jeffrey M.

    2016-01-01

    Highlights: • The role of PPARβ/δ in HBV-induced liver cancer was examined. • PPARβ/δ inhibits steatosis, inflammation, tumor multiplicity and promotes apoptosis. • Kupffer cell PPARβ/δ mediates these effects independent of DNA binding. - Abstract: Peroxisome proliferator-activated receptor-β/δ (PPARβ/δ) inhibits steatosis and inflammation, known risk factors for liver cancer. In this study, the effect of ligand activation of PPARβ/δ in modulating liver tumorigenesis in transgenic hepatitis B virus (HBV) mice was examined. Activation of PPARβ/δ in HBV mice reduced steatosis, the average number of liver foci, and tumor multiplicity. Reduced expression of hepatic CYCLIN D1 and c-MYC, tumor necrosis factor alpha (Tnfa) mRNA, serum levels of alanine aminotransaminase, and an increase in apoptotic signaling was also observed following ligand activation of PPARβ/δ in HBV mice compared to controls. Inhibition of Tnfa mRNA expression was not observed in wild-type hepatocytes. Ligand activation of PPARβ/δ inhibited lipopolysaccharide (LPS)-induced mRNA expression of Tnfa in wild-type, but not in Pparβ/δ-null Kupffer cells. Interestingly, LPS-induced expression of Tnfa mRNA was also inhibited in Kupffer cells from a transgenic mouse line that expressed a DNA binding mutant form of PPARβ/δ compared to controls. Combined, these results suggest that ligand activation of PPARβ/δ attenuates hepatic tumorigenesis in HBV transgenic mice by inhibiting steatosis and cell proliferation, enhancing hepatocyte apoptosis, and modulating anti-inflammatory activity in Kupffer cells.

  8. Targeting the Peroxisome Proliferator-Activated Receptor-γ to Counter the Inflammatory Milieu in Obesity

    Directory of Open Access Journals (Sweden)

    Cesar Corzo

    2013-12-01

    Full Text Available Adipose tissue, which was once viewed as a simple organ for storage of triglycerides, is now considered an important endocrine organ. Abnormal adipose tissue mass is associated with defects in endocrine and metabolic functions which are the underlying causes of the metabolic syndrome. Many adipokines, hormones secreted by adipose tissue, regulate cells from the immune system. Interestingly, most of these adipokines are proinflammatory mediators, which increase dramatically in the obese state and are believed to be involved in the pathogenesis of insulin resistance. Drugs that target peroxisome proliferator-activated receptor-γ have been shown to possess anti-inflammatory effects in animal models of diabetes. These findings, and the link between inflammation and the metabolic syndrome, will be reviewed here.

  9. Peroxisome Proliferator-Activated Receptors (PPARs as Potential Inducers of Antineoplastic Effects in CNS Tumors

    Directory of Open Access Journals (Sweden)

    Lars Tatenhorst

    2008-01-01

    Full Text Available The peroxisome proliferator-activated receptors (PPARs are ligand-inducible transcription factors which belong to the superfamily of nuclear hormone receptors. In recent years it turned out that natural as well as synthetic PPAR agonists exhibit profound antineoplastic as well as redifferentiation effects in tumors of the central nervous system (CNS. The molecular understanding of the underlying mechanisms is still emerging, with partially controverse findings reported by a number of studies dealing with the influence of PPARs on treatment of tumor cells in vitro. Remarkably, studies examining the effects of these drugs in vivo are just beginning to emerge. However, the agonists of PPARs, in particular the thiazolidinediones, seem to be promising candidates for new approaches in human CNS tumor therapy.

  10. American alliances and nuclear non-proliferation. The end of nuclear weapon activities of US allies

    International Nuclear Information System (INIS)

    Schneider, Jonas

    2016-01-01

    Jonas Schneider tackles a question that is of great interest both to scholars of nuclear proliferation and to practitioners of nonproliferation diplomacy: Why do some political leaders of U.S. allies agree to abandon their nation's nuclear weapons activities, while others - who are often members of the same allied government and sometimes even of the same political party - steadfastly reject such a course reversal? Our existing stock of theories does not fare well in accounting for this important variation in leaders' attitudes. To solve this puzzle, Schneider develops an innovative theory that draws on the individual status conceptions of allied political leaders. Subsequently, the author undertakes to test his theory using four thoroughly researched case studies, and he derives important lessons for international nonproliferation diplomacy toward the Middle East and Northeast Asia.

  11. PEROXISOME PROLIFERATOR-ACTIVATED RECEPTOR (PPAR) AGONISTS AS PROMISING NEW MEDICATIONS FOR DRUG ADDICTION: PRECLINICAL EVIDENCE

    Science.gov (United States)

    Foll, Bernard Le; Ciano, Patricia Di; Panlilio, Leigh V.; Goldberg, Steven R.; Ciccocioppo, Roberto

    2013-01-01

    This review examines the growing literature on the role of peroxisome proliferator-activated receptors (PPARs) in addiction. There are two subtypes of PPAR receptors that have been studied in addiction: PPAR-α and PPAR-γ. The role of each PPAR subtype in common models of addictive behavior, mainly pre-clinical models, is summarized. In particular, studies are reviewed that investigated the effects of PPAR-α agonists on relapse, sensitization, conditioned place preference, withdrawal and drug intake, and effects of PPAR-γ agonists on relapse, withdrawal and drug intake. Finally, studies that investigated the effects of PPAR agonists on neural pathways of addiction are reviewed. Taken together this preclinical data indicates that PPAR agonists are promising new medications for drug addiction treatment. PMID:23614675

  12. Activation of Penile Proadipogenic Peroxisome Proliferator-Activated Receptor with an Estrogen: Interaction with Estrogen Receptor Alpha during Postnatal Development

    Directory of Open Access Journals (Sweden)

    Mahmoud M. Mansour

    2008-01-01

    Full Text Available Exposure to the estrogen receptor alpha (ER ligand diethylstilbesterol (DES between neonatal days 2 to 12 induces penile adipogenesis and adult infertility in rats. The objective of this study was to investigate the in vivo interaction between DES-activated ER and the proadipogenic transcription factor peroxisome proliferator-activated receptor gamma (PPAR. Transcripts for PPARs , , and and 1a splice variant were detected in Sprague-Dawley normal rat penis with PPAR predominating. In addition, PPAR1b and PPAR2 were newly induced by DES. The PPAR transcripts were significantly upregulated with DES and reduced by antiestrogen ICI 182, 780. At the cellular level, PPAR protein was detected in urethral transitional epithelium and stromal, endothelial, neuronal, and smooth muscular cells. Treatment with DES activated ER and induced adipocyte differentiation in corpus cavernosum penis. Those adipocytes exhibited strong nuclear PPAR expression. These results suggest a biological overlap between PPAR and ER and highlight a mechanism for endocrine disruption.

  13. Haplotypes of the porcine peroxisome proliferator-activated receptor delta gene are associated with backfat thickness

    Directory of Open Access Journals (Sweden)

    Blöcker Helmut

    2009-11-01

    Full Text Available Abstract Background Peroxisome proliferator-activated receptor delta belongs to the nuclear receptor superfamily of ligand-inducible transcription factors. It is a key regulator of lipid metabolism. The peroxisome proliferator-activated receptor delta gene (PPARD has been assigned to a region on porcine chromosome 7, which harbours a quantitative trait locus for backfat. Thus, PPARD is considered a functional and positional candidate gene for backfat thickness. The purpose of this study was to test this candidate gene hypothesis in a cross of breeds that were highly divergent in lipid deposition characteristics. Results Screening for genetic variation in porcine PPARD revealed only silent mutations. Nevertheless, significant associations between PPARD haplotypes and backfat thickness were observed in the F2 generation of the Mangalitsa × Piétrain cross as well as a commercial German Landrace population. Haplotype 5 is associated with increased backfat in F2 Mangalitsa × Piétrain pigs, whereas haplotype 4 is associated with lower backfat thickness in the German Landrace population. Haplotype 4 and 5 carry the same alleles at all but one SNP. Interestingly, the opposite effects of PPARD haplotypes 4 and 5 on backfat thickness are reflected by opposite effects of these two haplotypes on PPAR-δ mRNA levels. Haplotype 4 significantly increases PPAR-δ mRNA levels, whereas haplotype 5 decreases mRNA levels of PPAR-δ. Conclusion This study provides evidence for an association between PPARD and backfat thickness. The association is substantiated by mRNA quantification. Further studies are required to clarify, whether the observed associations are caused by PPARD or are the result of linkage disequilibrium with a causal variant in a neighbouring gene.

  14. Peroxisome proliferator-activated receptors (PPARs) as therapeutic target in neurodegenerative disorders

    International Nuclear Information System (INIS)

    Agarwal, Swati; Yadav, Anuradha; Chaturvedi, Rajnish Kumar

    2017-01-01

    Peroxisome proliferator-activated receptors (PPARs) are nuclear receptors and they serve to be a promising therapeutic target for several neurodegenerative disorders, which includes Parkinson disease, Alzheimer's disease, Huntington disease and Amyotrophic Lateral Sclerosis. PPARs play an important role in the downregulation of mitochondrial dysfunction, proteasomal dysfunction, oxidative stress, and neuroinflammation, which are the major causes of the pathogenesis of neurodegenerative disorders. In this review, we discuss about the role of PPARs as therapeutic targets in neurodegenerative disorders. Several experimental approaches suggest potential application of PPAR agonist as well as antagonist in the treatment of neurodegenerative disorders. Several epidemiological studies found that the regular usage of PPAR activating non-steroidal anti-inflammatory drugs is effective in decreasing the progression of neurodegenerative diseases including PD and AD. We also reviewed the neuroprotective effects of PPAR agonists and associated mechanism of action in several neurodegenerative disorders both in vitro as well as in vivo animal models. - Highlights: • Peroxisome -activated receptors (PPARs) serve to be a promising therapeutic target for several neurodegenerative disorders. • PPAR agonist as well as provides neuroprotection in vitro as well as in vivo animal models of neurodegenerative disorders. • PPAR activating anti-inflammatory drugs use is effective in decreasing progression of neurodegenerative diseases.

  15. Identification of novel peroxisome proliferator-activated receptor-gamma (PPARγ) agonists using molecular modeling method

    Science.gov (United States)

    Gee, Veronica M. W.; Wong, Fiona S. L.; Ramachandran, Lalitha; Sethi, Gautam; Kumar, Alan Prem; Yap, Chun Wei

    2014-11-01

    Peroxisome proliferator-activated receptor-gamma (PPARγ) plays a critical role in lipid and glucose homeostasis. It is the target of many drug discovery studies, because of its role in various disease states including diabetes and cancer. Thiazolidinediones, a synthetic class of agents that work by activation of PPARγ, have been used extensively as insulin-sensitizers for the management of type 2 diabetes. In this study, a combination of QSAR and docking methods were utilised to perform virtual screening of more than 25 million compounds in the ZINC library. The QSAR model was developed using 1,517 compounds and it identified 42,378 potential PPARγ agonists from the ZINC library, and 10,000 of these were selected for docking with PPARγ based on their diversity. Several steps were used to refine the docking results, and finally 30 potentially highly active ligands were identified. Four compounds were subsequently tested for their in vitro activity, and one compound was found to have a K i values of <5 μM.

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

    International Nuclear Information System (INIS)

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

    2014-01-01

    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 + ) 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

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

    Energy Technology Data Exchange (ETDEWEB)

    Reinbothe, Susann; Larsson, Anna-Maria; Vaapil, Marica; Wigerup, Caroline [Department of Laboratory Medicine, Translational Cancer Research, Medicon Village, Lund University, SE-223 81 Lund (Sweden); CREATE Health, Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv (Israel); Sun, Jianmin [Department of Laboratory Medicine, Translational Cancer Research, Medicon Village, Lund University, SE-223 81 Lund (Sweden); Jögi, Annika [Department of Laboratory Medicine, Translational Cancer Research, Medicon Village, Lund University, SE-223 81 Lund (Sweden); CREATE Health, Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv (Israel); Neumann, Drorit [Department of Cell and Developmental Biology, Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv (Israel); Rönnstrand, Lars [Department of Laboratory Medicine, Translational Cancer Research, Medicon Village, Lund University, SE-223 81 Lund (Sweden); Påhlman, Sven, E-mail: sven.pahlman@med.lu.se [Department of Laboratory Medicine, Translational Cancer Research, Medicon Village, Lund University, SE-223 81 Lund (Sweden); CREATE Health, Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv (Israel)

    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.

  18. Peroxisome Proliferator-Activated Receptor ß/ (PPARß/) but Not PPAR Serves as a Plasma Free Fatty Acid Sensor in Liver

    NARCIS (Netherlands)

    Sanderson, L.; Degerhardt, T.; Desvergne, B.; Koppen, A.; Kalkhoven, E.; Müller, M.R.; Kersten, A.H.

    2009-01-01

    Peroxisome proliferator-activated receptor alpha (PPAR alpha) is an important transcription factor in liver that can be activated physiologically by fasting or pharmacologically by using high-affinity synthetic agonists. Here we initially set out to elucidate the similarities in gene induction

  19. Effect of Piper chaba Hunter, Piper sarmentosum Roxb. and Piper interruptum Opiz. on natural killer cell activity and lymphocyte proliferation.

    Science.gov (United States)

    Panthong, Sumalee; Itharat, Arunporn

    2014-08-01

    Immune system is the most important system ofhuman body. Thaifolk doctors have used some medicinal plants as an adaptogenic drug or immunomodulatory agent. Piper chaba Hunter, Piper sarmentosum Roxb. and Piper interruptum Opiz. are used by folk doctors to activate immune response in cancer patients. To investigate the effect on natural killer cell activity and on lymphocyte proliferation activity of water extract of P chaba Hunter P. sarmentosum Roxb. and P interruptum Opiz. MATERIAL ANDMETHOD: Plant materials were extracted by decoction method. All extracts were testedfor an immunomodulatory effect using PBMCs from twelve healthy donors by chromium release assay. Lymphocyte proliferation was also determined by 3H-thymidine uptake assay. The degree of activation was expressed as the stimulation index. The water extract of P chaba Hunter significantly increased lymphocyte proliferation at concentrations ofl ng/ml, 10 ng/ml, 1 μg/ml, 5 μg/ml, 10 μg/ml and 100 μg/ml. P sarmentosum Roxb., and P interruptum Opiz. extracts at those concentrations significantly stimulated lymphocyteproliferation. P sarmentosum Roxb. extractsignificantly increased natural killer (NK) cell activity at a concentration of 100 μg/ml but P chaba Hunter and P interruptum Opiz. extracts did not significantly stimulate natural killer cell activity. P chaba Hunter, P interruptum Opiz. andP sarmentosum Roxb. have an immunomodulatory effect especially for P sarmentosum Roxb. extract which can activate both lymphocyte proliferation and NK cell activity.

  20. The effect of quercetin and kaempferol aglycones and glucuronides on peroxisome proliferator-activated receptor-gamma (PPAR-¿)

    NARCIS (Netherlands)

    Beekmann, K.; Rubió, L.; Haan, de L.H.J.; Actis Goretta, L.; Burg, van der B.; Bladeren, van P.J.; Rietjens, I.M.C.M.

    2015-01-01

    The consumption of dietary flavonoids has been associated with a variety of health benefits, including effects mediated by the activation of peroxisome proliferator-activated receptor-gamma (PPAR-¿). Flavonoids are extensively metabolized during and after uptake and there is little known on the

  1. Anti-proliferation activity of terpenoids isolated from Euphorbia kansui in human cancer cells and their structure-activity relationship.

    Science.gov (United States)

    Hou, Jin-Jun; Shen, Yao; Yang, Zhou; Fang, Lin; Cai, Lu-Ying; Yao, Shuai; Long, Hua-Li; Wu, Wan-Ying; Guo, De-An

    2017-10-01

    Euphorbia kansui is a commonly used traditional Chinese medicine for the treatment of edema, pleural effusion, and asthma, etc. According to the previous researches, terpenoids in E. kansui possess various biological activities, e.g., anti-virus, anti-allergy, antitumor effects. In this work, twenty five terpenoids were isolated from E. kansui, including thirteen ingenane- and eight jatrophane-type diterpenoids (with two new compounds, kansuinin P and Q) and four triterpenoids. Eighteen of them were analyzed by MTS assay for in vitro anticancer activity in five human cancer cell lines. Structure-activity relationship for 12 ingenane-type diterpenoids in colorectal cancer Colo205 cells were preliminary studied. Significant anti-proliferation activities were observed in human melanoma cells breast cancer MDA-MB-435 cells and Colo205 cells. More than half of the isolated ingenane-type diterpenoids showed inhibitory activities in MDA-MB-435 cells. Eight ingenane- and one jatrophane-type diterpenoids possessed much lower IC 50 values in MDA-MB-435 cells than positive control staurosporine. Preliminary structure-activity relationship analysis showed that substituent on position 20 was important for the activity of ingenane-type diterpenoids in Colo205 cells and substituent on position 3 contributed more significant biological activity of the compounds than that on position 5 in both MDA-MB-435 and Colo205 cells. Copyright © 2017 China Pharmaceutical University. Published by Elsevier B.V. All rights reserved.

  2. Ubiquitin-activating enzyme is necessary for 17β-estradiol-induced breast cancer cell proliferation and migration.

    Science.gov (United States)

    Pesiri, Valeria; Totta, Pierangela; Marino, Maria; Acconcia, Filippo

    2014-08-01

    The sex steroid hormone 17β-estradiol (E2) regulates breast cancer (BC) cell proliferation and migration through the activation of a plethora of signal transduction cascades (e.g., PI3K/AKT activation) starting after E2 binding to the estrogen receptor alpha (ERα). The activity of the ubiquitin (Ub)-system modulates many physiological processes (e.g., cell proliferation and migration), and recently, a specific inhibitor (Pyr-41) of the Ub-activating enzyme (E1), which works as the activator of the Ub-based signaling, has been identified to prevent the functions of the Ub-system. Here, by using Pyr-41, we studied the involvement of the Ub-system in E2-induced signaling to proliferation and migration of BC cells. Our data indicate that E1 activity is involved in the E2:ERα signaling important for cell proliferation and migration through the modulation of the E2-evoked activation of the PI3K/AKT and the p38/MAPK pathways. These discoveries indicate a new molecular circuitry that can be further explored to define new opportunities for BC treatment. © 2014 International Union of Biochemistry and Molecular Biology.

  3. Genetic Validation of Cell Proliferation via Ras-Independent Activation of the Raf/Mek/Erk Pathway.

    Science.gov (United States)

    Lechuga, Carmen G; Simón-Carrasco, Lucía; Jacob, Harrys K C; Drosten, Matthias

    2017-01-01

    Signaling transmitted by the Ras family of small GTPases (H-, N-, and K-Ras) is essential for proliferation of mouse embryonic fibroblasts (MEFs). However, constitutive activation of the downstream Raf/Mek/Erk pathway can bypass the requirement for Ras proteins and allow cells to proliferate in the absence of the three Ras isoforms. Here we describe a protocol for a colony formation assay that permits evaluating the role of candidate proteins that are positive or negative regulators of cell proliferation mediated via Ras-independent Raf/Mek/Erk pathway activation. K-Ras lox (H-Ras -/- , N-Ras -/- , K-Ras lox/lox , RERT ert/ert ) MEFs are infected with retro- or lentiviral vectors expressing wild-type or constitutively activated candidate cDNAs, shRNAs, or sgRNAs in combination with Cas9 to ascertain the possibility of candidate proteins to function either as an activator or inhibitor of Ras-independent Raf/Mek/Erk activation. These cells are then seeded in the absence or presence of 4-Hydroxytamoxifen (4-OHT), which activates the resident CreERT2 alleles resulting in elimination of the conditional K-Ras alleles and ultimately generating Rasless cells. Colony formation in the presence of 4-OHT indicates cell proliferation via Ras-independent Raf/Mek/Erk activation.

  4. Mitofusin 2 decreases intracellular lipids in macrophages by regulating peroxisome proliferator-activated receptor-γ

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Chun; Ge, Beihai [Department of Cardiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1095 Jiefang Avenue, Wuhan 430030 (China); He, Chao [Department of Cardiology, China Three Gorges University, Yichang 433000 (China); Zhang, Yi; Liu, Xiaowen [Department of Cardiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1095 Jiefang Avenue, Wuhan 430030 (China); Liu, Kejian [Department of Cardiology, The First Affiliated Hospital of Medical College, Shihezi University (China); Qian, Cuiping; Zhang, Yu; Peng, Wenzhong [Department of Cardiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1095 Jiefang Avenue, Wuhan 430030 (China); Guo, Xiaomei, E-mail: xmguo@tjh.tjmu.edu.cn [Department of Cardiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1095 Jiefang Avenue, Wuhan 430030 (China)

    2014-07-18

    Highlights: • Mfn2 decreases cellular lipid accumulation by activating cholesterol transporters. • PPARγ is involved in the Mfn2-mediated increase of cholesterol transporter expressions. • Inactivation of ERK1/2 and p38 is involved in Mfn2-induced PPARγ expression. - Abstract: Mitofusin 2 (Mfn2) inhibits atherosclerotic plaque formation, but the underlying mechanism remains elusive. This study aims to reveal how Mfn2 functions in the atherosclerosis. Mfn2 expression was found to be significantly reduced in arterial atherosclerotic lesions of both mice and human compared with healthy counterparts. Here, we observed that Mfn2 increased cellular cholesterol transporter expression in macrophages by upregulating peroxisome proliferator-activated receptor-γ, an effect achieved at least partially by inhibiting extracellular signal-regulated kinase1/2 (ERK1/2) and p38 mitogen-activated protein kinases (MAPKs) pathway. These findings provide insights into potential mechanisms of Mfn2-mediated alterations in cholesterol transporter expression, which may have significant implications for the treatment of atherosclerotic heart disease.

  5. Mitofusin 2 decreases intracellular lipids in macrophages by regulating peroxisome proliferator-activated receptor-γ

    International Nuclear Information System (INIS)

    Liu, Chun; Ge, Beihai; He, Chao; Zhang, Yi; Liu, Xiaowen; Liu, Kejian; Qian, Cuiping; Zhang, Yu; Peng, Wenzhong; Guo, Xiaomei

    2014-01-01

    Highlights: • Mfn2 decreases cellular lipid accumulation by activating cholesterol transporters. • PPARγ is involved in the Mfn2-mediated increase of cholesterol transporter expressions. • Inactivation of ERK1/2 and p38 is involved in Mfn2-induced PPARγ expression. - Abstract: Mitofusin 2 (Mfn2) inhibits atherosclerotic plaque formation, but the underlying mechanism remains elusive. This study aims to reveal how Mfn2 functions in the atherosclerosis. Mfn2 expression was found to be significantly reduced in arterial atherosclerotic lesions of both mice and human compared with healthy counterparts. Here, we observed that Mfn2 increased cellular cholesterol transporter expression in macrophages by upregulating peroxisome proliferator-activated receptor-γ, an effect achieved at least partially by inhibiting extracellular signal-regulated kinase1/2 (ERK1/2) and p38 mitogen-activated protein kinases (MAPKs) pathway. These findings provide insights into potential mechanisms of Mfn2-mediated alterations in cholesterol transporter expression, which may have significant implications for the treatment of atherosclerotic heart disease

  6. Activation of Peroxisome Proliferator-Activated Receptor Alpha Improves Aged and UV-Irradiated Skin by Catalase Induction.

    Science.gov (United States)

    Shin, Mi Hee; Lee, Se-Rah; Kim, Min-Kyoung; Shin, Chang-Yup; Lee, Dong Hun; Chung, Jin Ho

    2016-01-01

    Peroxisome proliferator-activated receptor alpha (PPARα) is a nuclear hormone receptor involved in the transcriptional regulation of lipid metabolism, fatty acid oxidation, and glucose homeostasis. Its activation stimulates antioxidant enzymes such as catalase, whose expression is decreased in aged human skin. Here we investigated the expression of PPARα in aged and ultraviolet (UV)-irradiated skin, and whether PPARα activation can modulate expressions of matrix metalloproteinase (MMP)-1 and procollagen through catalase regulation. We found that PPARα mRNA level was significantly decreased in intrinsically aged and photoaged human skin as well as in UV-irradiated skin. A PPARα activator, Wy14643, inhibited UV-induced increase of MMP-1 and decrease of procollagen expression and caused marked increase in catalase expression. Furthermore, production of reactive oxygen species (ROS) was suppressed by Wy14643 in UV-irradiated and aged dermal fibroblasts, suggesting that the PPARα activation-induced upregulation of catalase leads to scavenging of ROS produced due to UV irradiation or aging. PPARα knockdown decreased catalase expression and abolished the beneficial effects of Wy14643. Topical application of Wy14643 on hairless mice restored catalase activity and prevented MMP-13 and inflammatory responses in skin. Our findings indicate that PPARα activation triggers catalase expression and ROS scavenging, thereby protecting skin from UV-induced damage and intrinsic aging.

  7. Synthesis and evaluation of fatty acid amides on the N-oleoylethanolamide-like activation of peroxisome proliferator activated receptor α.

    Science.gov (United States)

    Takao, Koichi; Noguchi, Kaori; Hashimoto, Yosuke; Shirahata, Akira; Sugita, Yoshiaki

    2015-01-01

    A series of fatty acid amides were synthesized and their peroxisome proliferator-activated receptor α (PPAR-α) agonistic activities were evaluated in a normal rat liver cell line, clone 9. The mRNAs of the PPAR-α downstream genes, carnitine-palmitoyltransferase-1 and mitochondrial 3-hydroxy-3-methylglutaryl-CoA synthase, were determined by real-time reverse transcription-polymerase chain reaction (RT-PCR) as PPAR-α agonistic activities. We prepared nine oleic acid amides. Their PPAR-α agonistic activities were, in decreasing order, N-oleoylhistamine (OLHA), N-oleoylglycine, Oleamide, N-oleoyltyramine, N-oleoylsertonin, and Olvanil. The highest activity was found with OLHA. We prepared and evaluated nine N-acylhistamines (N-acyl-HAs). Of these, OLHA, C16:0-HA, and C18:1Δ(9)-trans-HA showed similar activity. Activity due to the different chain length of the saturated fatty acid peaked at C16:0-HA. The PPAR-α antagonist, GW6471, inhibited the induction of the PPAR-α downstream genes by OLHA and N-oleoylethanolamide (OEA). These data suggest that N-acyl-HAs could be considered new PPAR-α agonists.

  8. Peroxisome proliferator-activated receptor gamma recruits the positive transcription elongation factor b complex to activate transcription and promote adipogenesis

    DEFF Research Database (Denmark)

    Iankova, Irena; Petersen, Rasmus K; Annicotte, Jean-Sébastien

    2006-01-01

    Positive transcription elongation factor b (P-TEFb) phosphorylates the C-terminal domain of RNA polymerase II, facilitating transcriptional elongation. In addition to its participation in general transcription, P-TEFb is recruited to specific promoters by some transcription factors such as c......-Myc or MyoD. The P-TEFb complex is composed of a cyclin-dependent kinase (cdk9) subunit and a regulatory partner (cyclin T1, cyclin T2, or cyclin K). Because cdk9 has been shown to participate in differentiation processes, such as muscle cell differentiation, we studied a possible role of cdk9...... with and phosphorylation of peroxisome proliferator-activated receptor gamma (PPARgamma), which is the master regulator of this process, on the promoter of PPARgamma target genes. PPARgamma-cdk9 interaction results in increased transcriptional activity of PPARgamma and therefore increased adipogenesis....

  9. Synthesis and biological evaluation of 2-heteroarylthioalkanoic acid analogues of clofibric acid as peroxisome proliferator-activated receptor alpha agonists.

    Science.gov (United States)

    Giampietro, Letizia; Ammazzalorso, Alessandra; Giancristofaro, Antonella; Lannutti, Fabio; Bettoni, Giancarlo; De Filippis, Barbara; Fantacuzzi, Marialuigia; Maccallini, Cristina; Petruzzelli, Michele; Morgano, Annalisa; Moschetta, Antonio; Amoroso, Rosa

    2009-10-22

    A series of 2-heteroarylthioalkanoic acids were synthesized through systematic structural modifications of clofibric acid and evaluated for human peroxisome proliferator-activated receptor alpha (PPARalpha) transactivation activity, with the aim of obtaining new hypolipidemic compounds. Some thiophene and benzothiazole derivatives showing a good activation of the receptor alpha were screened for activity against the PPARgamma isoform. The gene induction of selected compounds was also investigated in the human hepatoma cell line.

  10. DAX-1 Inhibits Hepatocellular Carcinoma Proliferation by Inhibiting β-Catenin Transcriptional Activity

    Directory of Open Access Journals (Sweden)

    Hong-Lei Jiang

    2014-08-01

    Full Text Available Background/Aims: Hepatocellular carcinoma (HCC represents the most common type of liver cancer. DAX1 (dosage-sensitive sex reversal adrenal hypoplasia congenital critical region on X chromosome, gene 1, an atypical member of the nuclear receptor family due to lack of classical DNA-binding domains, has been known for its fundamental roles in the development, especially in the sex determination and steroidogenesis. Previous studies also showed that DAX-1 played a critical role in endocrine and sex steroid-dependent neoplasms such as adrenocortical, pituitary, endometrial, and ovarian tumors. However, its biological roles in the development of HCC remain largely unexplored. Methods: Real-time PCR and Western blot were used to detect the expression of DAX-1 in HCC tissues and cell lines. Immunoprecipitation (IP assay was used to show the interaction between DAX-1 and β-Catenin. Small interfering RNA (siRNA was used to silence the expression of DAX-1. BrdU incorporation and Cell-cycle assays were used to detect the role of DAX-1 in HCC cells proliferation. Migration and invasion assays were carried out to test the metastasis ability of DAX-1 in HCC cells. Results: In the present study, we found that mRNA and protein levels of DAX-1 were down-regulated in HCC tissues and cell lines. Furthermore, overexpression of DAX-1 could inhibit while its knockdown using small interfering RNA promoted cell proliferation in several HCC cell lines. At the molecular level, we demonstrated that DAX-1 could interact with β-Catenin and attenuate its transcriptional activity. Conclusion: Therefore, our results suggest a previously unknown DAX-1/β-Catenin molecular network controlling HCC development.

  11. Clofibric acid, a peroxisome proliferator-activated receptor alpha ligand, inhibits growth of human ovarian cancer.

    Science.gov (United States)

    Yokoyama, Yoshihito; Xin, Bing; Shigeto, Tatsuhiko; Umemoto, Mika; Kasai-Sakamoto, Akiko; Futagami, Masayuki; Tsuchida, Shigeki; Al-Mulla, Fahd; Mizunuma, Hideki

    2007-04-01

    Recent reports have shown that peroxisome proliferator-activated receptor (PPAR)alpha ligands reduce growth of some types of malignant tumors and prevent carcinogenesis. In this study, we investigated the inhibitory effect of clofibric acid (CA), a ligand for PPARalpha on growth of ovarian malignancy, in in vivo and in vitro experiments using OVCAR-3 and DISS cells derived from human ovarian cancer and aimed to elucidate the molecular mechanism of its antitumor effect. CA treatment significantly suppressed the growth of OVCAR-3 tumors xenotransplanted s.c. and significantly prolonged the survival of mice with malignant ascites derived from DISS cells as compared with control. CA also dose-dependently inhibited cell proliferation of cultured cell lines. CA treatment increased the expression of carbonyl reductase (CR), which promotes the conversion of prostaglandin E(2) (PGE(2)) to PGF(2alpha), in implanted OVCAR-3 tumors as well as cultured cells. CA treatment decreased PGE(2) level as well as vascular endothelial growth factor (VEGF) amount in both of OVCAR-3-tumor and DISS-derived ascites. Reduced microvessel density and induced apoptosis were found in solid OVCAR-3 tumors treated by CA. Transfection of CR expression vector into mouse ovarian cancer cells showed significant reduction of PGE(2) level as well as VEGF expression. These results indicate that CA produces potent antitumor effects against ovarian cancer in conjunction with a reduction of angiogenesis and induction of apoptosis. We conclude that CA could be an effective agent in ovarian cancer and should be tested alone and in combination with other anticancer drugs.

  12. Laboratory Activity to Teach about the Proliferation of Salmonella in Vegetables

    Directory of Open Access Journals (Sweden)

    Massimiliano Marvasi

    2015-08-01

    Full Text Available We designed a three-week laboratory experience that can complement any microbiology teaching laboratory to expand students’ knowledge of the ecology of human enteric pathogens outside of their animal hosts. Through their participation in this laboratory activity, students learned that vegetative and reproductive plant parts could be a natural habitat for enteric bacteria such as non-typhoidal strains of Salmonella enterica. This field was recently brought to the forefront of the scientific community and public interest by outbreaks of human illness linked to the consumption of fresh fruits and vegetables. Students were encouraged to develop their own testable hypotheses to compare proliferation of Salmonella enterica sv Typhimurium LT2 in different vegetables: cherry and regular-size  tomatoes, onions, lettuce, and yellow and red bell peppers (Escherichia coli can be substituted for BSL1 laboratories. Upon completion of the laboratory experience, students were able to: 1 Develop testable hypotheses addressing the ability of a human pathogen, Salmonella enterica, to colonize and proliferate in vegetables; 2 Determine that different vegetables support the growth of Salmonella to different extents; 3 Conduct statistical analysis and identify any significant differences. The teaching-learning process was assessed with a pre-/posttest, with an average increase in content understanding from ~15% to 85%. We also measured students’ proficiency while conducting specific technical tasks, revealing no major difficulties while conducting the experiments. Students indicated satisfaction with the organization and content of the practices. All of the students (100% agreed that the exercises improved their knowledge of this subject. Editor's Note:The ASM advocates that students must successfully demonstrate the ability to explain and practice safe laboratory techniques. For more information, read the laboratory safety section of the ASM Curriculum

  13. Soman poisoning increases neural progenitor proliferation and induces long-term glial activation in mouse brain

    International Nuclear Information System (INIS)

    Collombet, Jean-Marc; Four, Elise; Bernabe, Denis; Masqueliez, Catherine; Burckhart, Marie-France; Baille, Valerie; Baubichon, Dominique; Lallement, Guy

    2005-01-01

    To date, only short-term glial reaction has been extensively studied following soman or other warfare neurotoxicant poisoning. In a context of cell therapy by neural progenitor engraftment to repair brain damage, the long-term effect of soman on glial reaction and neural progenitor division was analyzed in the present study. The effect of soman poisoning was estimated in mouse brains at various times ranging from 1 to 90 days post-poisoning. Using immunochemistry and dye staining techniques (hemalun-eosin staining), the number of degenerating neurons, the number of dividing neural progenitors, and microglial, astroglial or oligodendroglial cell activation were studied. Soman poisoning led to rapid and massive (post-soman day 1) death of mature neurons as assessed by hemalun-eosin staining. Following this acute poisoning phase, a weak toxicity effect on mature neurons was still observed for a period of 1 month after poisoning. A massive short-termed microgliosis peaked on day 3 post-poisoning. Delayed astrogliosis was observed from 3 to 90 days after soman poisoning, contributing to glial scar formation. On the other hand, oligodendroglial cells or their precursors were practically unaffected by soman poisoning. Interestingly, neural progenitors located in the subgranular zone of the dentate gyrus (SGZ) or in the subventricular zone (SVZ) of the brain survived soman poisoning. Furthermore, soman poisoning significantly increased neural progenitor proliferation in both SGZ and SVZ brain areas on post-soman day 3 or day 8, respectively. This increased proliferation rate was detected up to 1 month after poisoning

  14. Metabolic adaptation to intermittent fasting is independent of peroxisome proliferator-activated receptor alpha.

    Science.gov (United States)

    Li, Guolin; Brocker, Chad N; Yan, Tingting; Xie, Cen; Krausz, Kristopher W; Xiang, Rong; Gonzalez, Frank J

    2018-01-01

    Peroxisome proliferator-activated receptor alpha (PPARA) is a major regulator of fatty acid oxidation and severe hepatic steatosis occurs during acute fasting in Ppara-null mice. Thus, PPARA is considered an important mediator of the fasting response; however, its role in other fasting regiments such as every-other-day fasting (EODF) has not been investigated. Mice were pre-conditioned using either a diet containing the potent PPARA agonist Wy-14643 or an EODF regimen prior to acute fasting. Ppara-null mice were used to assess the contribution of PPARA activation during the metabolic response to EODF. Livers were collected for histological, biochemical, qRT-PCR, and Western blot analysis. Acute fasting activated PPARA and led to steatosis, whereas EODF protected against fasting-induced hepatic steatosis without affecting PPARA signaling. In contrast, pretreatment with Wy-14,643 did activate PPARA signaling but did not ameliorate acute fasting-induced steatosis and unexpectedly promoted liver injury. Ppara ablation exacerbated acute fasting-induced hypoglycemia, hepatic steatosis, and liver injury in mice, whereas these detrimental effects were absent in response to EODF, which promoted PPARA-independent fatty acid metabolism and normalized serum lipids. These findings indicate that PPARA activation prior to acute fasting cannot ameliorate fasting-induced hepatic steatosis, whereas EODF induced metabolic adaptations to protect against fasting-induced steatosis without altering PPARA signaling. Therefore, PPARA activation does not mediate the metabolic adaptation to fasting, at least in preventing acute fasting-induced steatosis. Published by Elsevier GmbH.

  15. Metabolic adaptation to intermittent fasting is independent of peroxisome proliferator-activated receptor alpha

    Directory of Open Access Journals (Sweden)

    Guolin Li

    2018-01-01

    Full Text Available Background: Peroxisome proliferator-activated receptor alpha (PPARA is a major regulator of fatty acid oxidation and severe hepatic steatosis occurs during acute fasting in Ppara-null mice. Thus, PPARA is considered an important mediator of the fasting response; however, its role in other fasting regiments such as every-other-day fasting (EODF has not been investigated. Methods: Mice were pre-conditioned using either a diet containing the potent PPARA agonist Wy-14643 or an EODF regimen prior to acute fasting. Ppara-null mice were used to assess the contribution of PPARA activation during the metabolic response to EODF. Livers were collected for histological, biochemical, qRT-PCR, and Western blot analysis. Results: Acute fasting activated PPARA and led to steatosis, whereas EODF protected against fasting-induced hepatic steatosis without affecting PPARA signaling. In contrast, pretreatment with Wy-14,643 did activate PPARA signaling but did not ameliorate acute fasting-induced steatosis and unexpectedly promoted liver injury. Ppara ablation exacerbated acute fasting-induced hypoglycemia, hepatic steatosis, and liver injury in mice, whereas these detrimental effects were absent in response to EODF, which promoted PPARA-independent fatty acid metabolism and normalized serum lipids. Conclusions: These findings indicate that PPARA activation prior to acute fasting cannot ameliorate fasting-induced hepatic steatosis, whereas EODF induced metabolic adaptations to protect against fasting-induced steatosis without altering PPARA signaling. Therefore, PPARA activation does not mediate the metabolic adaptation to fasting, at least in preventing acute fasting-induced steatosis. Keywords: PPARA, PPARalpha, Intermittent fasting, Every-other-day fasting, Steatosis, Adaptive fasting response

  16. Piper betle shows antioxidant activities, inhibits MCF-7 cell proliferation and increases activities of catalase and superoxide dismutase

    Directory of Open Access Journals (Sweden)

    Abrahim Noor

    2012-11-01

    Full Text Available Abstract Background Breast cancer is the most common form of cancer and the focus on finding chemotherapeutic agents have recently shifted to natural products. Piper betle is a medicinal plant with various biological activities. However, not much data is available on the anti-cancer effects of P. betle on breast cancer. Due to the current interest in the potential effects of antioxidants from natural products in breast cancer treatment, we investigated the antioxidant activities of the leaves of P. betle and its inhibitory effect on the proliferation of the breast cancer cell line, MCF-7. Methods The leaves of P. betle were extracted with solvents of varying polarities (water, methanol, ethyl acetate and hexane and their phenolic and flavonoid content were determined using colorimetric assays. Phenolic composition was characterized using HPLC. Antioxidant activities were measured using FRAP, DPPH, superoxide anion, nitric oxide and hyroxyl radical scavenging assays. Biological activities of the extracts were analysed using MTT assay and antioxidant enzyme (catalase, superoxide dismutase, glutathione peroxidase assays in MCF-7 cells. Results Overall, the ethyl acetate extract showed the highest ferric reducing activity and radical scavenging activities against DPPH, superoxide anion and nitric oxide radicals. This extract also contained the highest phenolic content implying the potential contribution of phenolics towards the antioxidant activities. HPLC analyses revealed the presence of catechin, morin and quercetin in the leaves. The ethyl acetate extract also showed the highest inhibitory effect against the proliferation of MCF-7 cells (IC50=65 μg/ml. Treatment of MCF-7 cells with the plant extract increased activities of catalase and superoxide dismutase. Conclusions Ethyl acetate is the optimal solvent for the extraction of compounds with antioxidant and anti-proliferative activities. The increased activities of catalase and superoxide

  17. Piper betle shows antioxidant activities, inhibits MCF-7 cell proliferation and increases activities of catalase and superoxide dismutase.

    Science.gov (United States)

    Abrahim, Noor Nazirahanie; Kanthimathi, M S; Abdul-Aziz, Azlina

    2012-11-15

    Breast cancer is the most common form of cancer and the focus on finding chemotherapeutic agents have recently shifted to natural products. Piper betle is a medicinal plant with various biological activities. However, not much data is available on the anti-cancer effects of P. betle on breast cancer. Due to the current interest in the potential effects of antioxidants from natural products in breast cancer treatment, we investigated the antioxidant activities of the leaves of P. betle and its inhibitory effect on the proliferation of the breast cancer cell line, MCF-7. The leaves of P. betle were extracted with solvents of varying polarities (water, methanol, ethyl acetate and hexane) and their phenolic and flavonoid content were determined using colorimetric assays. Phenolic composition was characterized using HPLC. Antioxidant activities were measured using FRAP, DPPH, superoxide anion, nitric oxide and hyroxyl radical scavenging assays. Biological activities of the extracts were analysed using MTT assay and antioxidant enzyme (catalase, superoxide dismutase, glutathione peroxidase) assays in MCF-7 cells. Overall, the ethyl acetate extract showed the highest ferric reducing activity and radical scavenging activities against DPPH, superoxide anion and nitric oxide radicals. This extract also contained the highest phenolic content implying the potential contribution of phenolics towards the antioxidant activities. HPLC analyses revealed the presence of catechin, morin and quercetin in the leaves. The ethyl acetate extract also showed the highest inhibitory effect against the proliferation of MCF-7 cells (IC50=65 μg/ml). Treatment of MCF-7 cells with the plant extract increased activities of catalase and superoxide dismutase. Ethyl acetate is the optimal solvent for the extraction of compounds with antioxidant and anti-proliferative activities. The increased activities of catalase and superoxide dismutase in the treated cells could alter the antioxidant defense

  18. The transition from proliferation to differentiation in colorectal cancer is regulated by the calcium activated chloride channel A1.

    Directory of Open Access Journals (Sweden)

    Bo Yang

    Full Text Available Breaking the balance between proliferation and differentiation in animal cells can lead to cancer, but the mechanisms maintaining this balance remain largely undefined. The calcium activated chloride channel A1 (CLCA1 is a member of the calcium sensitive chloride conductance family of proteins and is expressed mainly in the colon, small intestine and appendix. We show that CLCA1 plays a functional role in differentiation and proliferation of Caco-2 cells and of intestinal tissue. Caco-2 cells spontaneously differentiate either in confluent culture or when treated with butyrate, a molecule present naturally in the diet. Here, we compared CLCA1 expressional levels between patients with and without colorectal cancer (CRC and determined the functional role of CLCA1 in differentiation and proliferation of Caco-2 cells. We showed that: 1 CLCA1 and CLCA4 expression were down-regulated significantly in CRC patients; 2 CLCA1 expression was up-regulated in Caco-2 cells induced to differentiate by confluent culture or by treatment with sodium butyrate (NaBT; 3 Knockdown of CLCA1 with siRNA significantly inhibited cell differentiation and promoted cell proliferation in Caco-2 confluent cultures, and 4 In Caco-2 3D culture, suppression of CLCA1 significantly increased cell proliferation and compromised NaBT-induced inhibition of proliferation. In conclusion, CLCA1 may contribute to promoting spontaneous differentiation and reducing proliferation of Caco-2 cells and may be a target of NaBT-induced inhibition of proliferation and therefore a potential diagnostic marker for CRC prognosis.

  19. Epidermis-type lipoxygenase 3 regulates adipocyte differentiation and peroxisome proliferator-activated receptor gamma activity

    DEFF Research Database (Denmark)

    Hallenborg, Philip; Jørgensen, Claus; Petersen, Rasmus K

    2010-01-01

    preadipocytes. Here, we show that forced expression of eLOX3 or addition of eLOX3 products stimulated adipogenesis under conditions that normally require an exogenous PPAR gamma ligand for differentiation. Hepoxilins, a group of oxidized arachidonic acid derivatives produced by eLOX3, bound to and activated...... PPAR gamma. Production of hepoxilins was increased transiently during the initial stages of adipogenesis. Furthermore, small interfering RNA-mediated or retroviral short hairpin RNA-mediated knockdown of eLOX3 expression abolished differentiation of 3T3-L1 preadipocytes. Finally, we demonstrate...... differentiation has remained enigmatic. Previously, we showed that lipoxygenase (LOX) activity is involved in activation of PPAR gamma during the early stages of adipocyte differentiation. Of the seven known murine LOXs, only the unconventional LOX epidermis-type lipoxygenase 3 (eLOX3) is expressed in 3T3-L1...

  20. Topical Rosiglitazone Treatment Improves Ulcerative Colitis by Restoring Peroxisome Proliferator-Activated Receptor-gamma Activity

    DEFF Research Database (Denmark)

    Pedersen, G.; Brynskov, Jørn

    2010-01-01

    and functional activity in human colonic epithelium and explored the potential of topical treatment with rosiglitazone (a PPAR gamma ligand) in patients with ulcerative colitis. METHODS: Spontaneous and rosiglitazone-mediated PPAR gamma and adipophillin expression (a gene transcriptionally activated by PPAR...... for 14 days. RESULTS: PPAR gamma expression was fourfold reduced in epithelial cells from inflamed compared with uninflamed mucosa and controls. Adipophillin levels were decreased in parallel. Rosiglitazone induced a concentration-dependent increase in adipophillin levels and restored PPAR gamma activity...... in epithelial cells from inflamed mucosa in vitro. Rosiglitazone enema treatment was well tolerated and reduced the Mayo ulcerative colitis score from 8.9 to 4.3 (P levels in the epithelial cells of the patients, indicating PPAR...

  1. The oncoprotein HBXIP upregulates PDGFB via activating transcription factor Sp1 to promote the proliferation of breast cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yingyi; Zhao, Yu; Li, Leilei; Shen, Yu; Cai, Xiaoli [Department of Biochemistry, College of Life Sciences, Nankai University, Tianjin 300071 (China); Zhang, Xiaodong, E-mail: zhangxd@nankai.edu.cn [Department of Cancer Research, Institute for Molecular Biology, College of Life Sciences, Nankai University, Tianjin 300071 (China); Ye, Lihong, E-mail: yelihong@nankai.edu.cn [Department of Biochemistry, College of Life Sciences, Nankai University, Tianjin 300071 (China)

    2013-05-03

    Highlights: •HBXIP is able to upregulate the expression of PDGFB in breast cancer cells. •HBXIP serves as a coactivator of activating transcription factor Sp1. •HBXIP stimulates the PDGFB promoter via activating transcription factor Sp1. •HBXIP promotes the proliferation of breast cancer cell via upregulating PDGFB. -- Abstract: We have reported that the oncoprotein hepatitis B virus X-interacting protein (HBXIP) acts as a novel transcriptional coactivator to promote proliferation and migration of breast cancer cells. Previously, we showed that HBXIP was able to activate nuclear factor-κB (NF-κB) in breast cancer cells. As an oncogene, the platelet-derived growth factor beta polypeptide (PDGFB) plays crucial roles in carcinogenesis. In the present study, we found that both HBXIP and PDGFB were highly expressed in breast cancer cell lines. Interestingly, HBXIP was able to increase transcriptional activity of NF-κB through PDGFB, suggesting that HBXIP is associated with PDGFB in the cells. Moreover, HBXIP was able to upregulate PDGFB at the levels of mRNA, protein and promoter in the cells. Then, we identified that HBXIP stimulated the promoter of PDGFB through activating transcription factor Sp1. In function, HBXIP enhanced the proliferation of breast cancer cells through PDGFB in vitro. Thus, we conclude that HBXIP upregulates PDGFB via activating transcription factor Sp1 to promote proliferation of breast cancer cells.

  2. The oncoprotein HBXIP upregulates PDGFB via activating transcription factor Sp1 to promote the proliferation of breast cancer cells

    International Nuclear Information System (INIS)

    Zhang, Yingyi; Zhao, Yu; Li, Leilei; Shen, Yu; Cai, Xiaoli; Zhang, Xiaodong; Ye, Lihong

    2013-01-01

    Highlights: •HBXIP is able to upregulate the expression of PDGFB in breast cancer cells. •HBXIP serves as a coactivator of activating transcription factor Sp1. •HBXIP stimulates the PDGFB promoter via activating transcription factor Sp1. •HBXIP promotes the proliferation of breast cancer cell via upregulating PDGFB. -- Abstract: We have reported that the oncoprotein hepatitis B virus X-interacting protein (HBXIP) acts as a novel transcriptional coactivator to promote proliferation and migration of breast cancer cells. Previously, we showed that HBXIP was able to activate nuclear factor-κB (NF-κB) in breast cancer cells. As an oncogene, the platelet-derived growth factor beta polypeptide (PDGFB) plays crucial roles in carcinogenesis. In the present study, we found that both HBXIP and PDGFB were highly expressed in breast cancer cell lines. Interestingly, HBXIP was able to increase transcriptional activity of NF-κB through PDGFB, suggesting that HBXIP is associated with PDGFB in the cells. Moreover, HBXIP was able to upregulate PDGFB at the levels of mRNA, protein and promoter in the cells. Then, we identified that HBXIP stimulated the promoter of PDGFB through activating transcription factor Sp1. In function, HBXIP enhanced the proliferation of breast cancer cells through PDGFB in vitro. Thus, we conclude that HBXIP upregulates PDGFB via activating transcription factor Sp1 to promote proliferation of breast cancer cells

  3. Ligand binding reduces SUMOylation of the peroxisome proliferator-activated receptor γ (PPARγ activation function 1 (AF1 domain.

    Directory of Open Access Journals (Sweden)

    Rolf Diezko

    Full Text Available Peroxisome proliferator-activated receptor gamma (PPARγ is a ligand-activated nuclear receptor regulating adipogenesis, glucose homeostasis and inflammatory responses. The activity of PPARγ is controlled by post-translational modifications including SUMOylation and phosphorylation that affects its biological and molecular functions. Several important aspects of PPARγ SUMOylation including SUMO isoform-specificity and the impact of ligand binding on SUMOylation remain unresolved or contradictory. Here, we present a comprehensive study of PPARγ1 SUMOylation. We show that PPARγ1 can be modified by SUMO1 and SUMO2. Mutational analyses revealed that SUMOylation occurs exclusively within the N-terminal activation function 1 (AF1 domain predominantly at lysines 33 and 77. Ligand binding to the C-terminal ligand-binding domain (LBD of PPARγ1 reduces SUMOylation of lysine 33 but not of lysine 77. SUMOylation of lysine 33 and lysine 77 represses basal and ligand-induced activation by PPARγ1. We further show that lysine 365 within the LBD is not a target for SUMOylation as suggested in a previous report, but it is essential for full LBD activity. Our results suggest that PPARγ ligands negatively affect SUMOylation by interdomain communication between the C-terminal LBD and the N-terminal AF1 domain. The ability of the LBD to regulate the AF1 domain may have important implications for the evaluation and mechanism of action of therapeutic ligands that bind PPARγ.

  4. Status and prospect of non-proliferation activities of ISTC and STCU

    International Nuclear Information System (INIS)

    Richard, M.; Daoust Maleval, D.; Louvet, P.

    2009-01-01

    This article examines the role of the International Science and Technology Centre of Moscow (ISTC) and the Science and Technology Centre of Ukraine in Kiev (STCU) in preventing proliferation of the weapons of mass destruction (WMD) expertise and know-how of scientists and engineers from the Former Soviet Union countries. The Centres were created in the first half of the nineties, in the context of the collapse of the Soviet Union. This collapse raised very serious concerns: over the risk of former WMD scientists and engineers being recruited by States of concern or terrorist groups that wished to develop their own WMD capabilities and means of delivery; and the possibility that scientists and engineers would be driven to sell their knowledge, know-how or equipment in order to survive. Since the Centres' inception, the regional and international context has changed dramatically at both economic and strategic levels, in particular regarding non-proliferation and global security. Changes of a political and strategic nature in the former Soviet Union required the European Union to review its relationship with Russia, to reassess the importance of Central Asian Countries and the future of Ukraine as it is pulled between Russia and Europe. The Centres have had to adapt to these changes. The article draws from an evaluation of the Centres' non-proliferation activities, carried out by the authors between November 2006 and September 2007 at the request of the European Commission. Moreover, since completion of the mission, many events, important for the strategic relationships between E U, Russia and other Commonwealth of Independent States (CIS) countries occurred as the affirmation of Russia's regional leadership: its rearmament along with the stiffening of its relationships with western countries and some neighbours and closure to visitors; the Georgia-Russia conflict; and the Russia-Ukraine gas crisis. As CIS countries are more affected by the current economical crisis

  5. RhoA-Rho kinase and platelet-activating factor stimulation of ovine foetal pulmonary vascular smooth muscle cell proliferation.

    Science.gov (United States)

    Renteria, L S; Austin, M; Lazaro, M; Andrews, M A; Lustina, J; Raj, J U; Ibe, B O

    2013-10-01

    Platelet-activating factor (PAF) is produced by pulmonary vascular smooth muscle cells (PVSMC). We studied effects of Rho kinase on PAF stimulation of PVSMC proliferation in an attempt to understand the role of RhoA/Rho kinase on PAF-induced ovine foetal pulmonary vascular remodelling. Our hypothesis is that PAF acts through Rho kinase, as one of its downstream signals, to induce arterial (SMC-PA) and venous (SMC-PV) cell proliferation in the hypoxic lung environment of the foetus, in utero. Rho kinase and MAPK effects on PAF receptor (PAFR)-mediated cell population expansion, and PAFR expression, were studied by DNA synthesis, western blot analysis and immunocytochemistry. Effects of constructs T19N and G14V on PAF-induced cell proliferation were also investigated. Hypoxia increased PVSMC proliferation and Rho kinase inhibitors, Y-27632 and Fasudil (HA-1077) as well as MAPK inhibitors PD 98059 and SB 203580 attenuated PAF stimulation of cell proliferation. RhoA T19N and G14V stimulated cell proliferation, but co-incubation with PAF did not affect proliferative effects of the constructs. PAFR protein expression was significantly downregulated in both cell types by both Y-27632 and HA-1077, with comparable profiles. Also, cells treated with Y-27632 had less PAF receptor fluorescence with significant disruption of cell morphology. Our results show that Rho kinase non-specifically modulated PAFR-mediated responses by a translational modification of PAFR protein, and suggest that, in vivo, activation of Rho kinase by PAF may be a further pathway to sustain PAFR-mediated PVSMC proliferation. © 2013 John Wiley & Sons Ltd.

  6. Activation of double-stranded RNA-dependent protein kinase inhibits proliferation of pancreatic β-cells

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Shan-Shan [Key Laboratory of Human Functional Genomics of Jiangsu Province, Nanjing Medical University, Nanjing (China); Department of Biochemistry and Molecular Biology, Nanjing Medical University, Nanjing (China); Jiang, Teng [Department of Neurology, Qingdao Municipal Hospital, Nanjing Medical University, Nanjing (China); Wang, Yi; Gu, Li-Ze [Key Laboratory of Human Functional Genomics of Jiangsu Province, Nanjing Medical University, Nanjing (China); Department of Biochemistry and Molecular Biology, Nanjing Medical University, Nanjing (China); Wu, Hui-Wen [Laboratory Center for Basic Medical Sciences, Nanjing Medical University, Nanjing (China); Tan, Lan [Department of Neurology, Qingdao Municipal Hospital, Nanjing Medical University, Nanjing (China); Guo, Jun, E-mail: Guoj@njmu.edu.cn [Key Laboratory of Human Functional Genomics of Jiangsu Province, Nanjing Medical University, Nanjing (China); Department of Biochemistry and Molecular Biology, Nanjing Medical University, Nanjing (China)

    2014-01-17

    Highlights: •PKR can be activated by glucolipitoxicity and pro-inflammatory cytokines in β-cells. •Activated PKR inhibited β-cell proliferation by arresting cell cycle at G1 phase. •Activated PKR fully abrogated the pro-proliferative effects of IGF-I on β-cells. -- Abstract: Double-stranded RNA-dependent protein kinase (PKR) is revealed to participate in the development of insulin resistance in peripheral tissues in type 2 diabetes (T2DM). Meanwhile, PKR is also characterized as a critical regulator of cell proliferation. To date, no study has focused on the impact of PKR on the proliferation of pancreatic β-cells. Here, we adopted insulinoma cell lines and mice islet β-cells to investigate: (1) the effects of glucolipotoxicity and pro-inflammatory cytokines on PKR activation; (2) the effects of PKR on proliferation of pancreatic β-cells and its underlying mechanisms; (3) the actions of PKR on pro-proliferative effects of IGF-I and its underlying pathway. Our results provided the first evidence that PKR can be activated by glucolipitoxicity and pro-inflammatory cytokines in pancreatic β-cells, and activated PKR significantly inhibited cell proliferation by arresting cell cycle at G1 phase. Reductions in cyclin D1 and D2 as well as increases in p27 and p53 were associated with the anti-proliferative effects of PKR, and proteasome-dependent degradation took part in the reduction of cyclin D1 and D2. Besides, PKR activation abrogated the pro-proliferative effects of IGF-I by activating JNK and disrupting IRS1/PI3K/Akt signaling pathway. These findings indicate that the anti-proliferative actions of PKR on pancreatic β-cells may contribute to the pathogenesis of T2DM.

  7. Activation of double-stranded RNA-dependent protein kinase inhibits proliferation of pancreatic β-cells

    International Nuclear Information System (INIS)

    Chen, Shan-Shan; Jiang, Teng; Wang, Yi; Gu, Li-Ze; Wu, Hui-Wen; Tan, Lan; Guo, Jun

    2014-01-01

    Highlights: •PKR can be activated by glucolipitoxicity and pro-inflammatory cytokines in β-cells. •Activated PKR inhibited β-cell proliferation by arresting cell cycle at G1 phase. •Activated PKR fully abrogated the pro-proliferative effects of IGF-I on β-cells. -- Abstract: Double-stranded RNA-dependent protein kinase (PKR) is revealed to participate in the development of insulin resistance in peripheral tissues in type 2 diabetes (T2DM). Meanwhile, PKR is also characterized as a critical regulator of cell proliferation. To date, no study has focused on the impact of PKR on the proliferation of pancreatic β-cells. Here, we adopted insulinoma cell lines and mice islet β-cells to investigate: (1) the effects of glucolipotoxicity and pro-inflammatory cytokines on PKR activation; (2) the effects of PKR on proliferation of pancreatic β-cells and its underlying mechanisms; (3) the actions of PKR on pro-proliferative effects of IGF-I and its underlying pathway. Our results provided the first evidence that PKR can be activated by glucolipitoxicity and pro-inflammatory cytokines in pancreatic β-cells, and activated PKR significantly inhibited cell proliferation by arresting cell cycle at G1 phase. Reductions in cyclin D1 and D2 as well as increases in p27 and p53 were associated with the anti-proliferative effects of PKR, and proteasome-dependent degradation took part in the reduction of cyclin D1 and D2. Besides, PKR activation abrogated the pro-proliferative effects of IGF-I by activating JNK and disrupting IRS1/PI3K/Akt signaling pathway. These findings indicate that the anti-proliferative actions of PKR on pancreatic β-cells may contribute to the pathogenesis of T2DM

  8. Cell proliferation and migration are modulated by Cdk-1-phosphorylated endothelial-monocyte activating polypeptide II.

    Directory of Open Access Journals (Sweden)

    Margaret A Schwarz

    Full Text Available Endothelial-Monocyte Activating Polypeptide (EMAP II is a secreted protein with well-established anti-angiogenic activities. Intracellular EMAP II expression is increased during fetal development at epithelial/mesenchymal boundaries and in pathophysiologic fibroproliferative cells of bronchopulmonary dysplasia, emphysema, and scar fibroblast tissue following myocardial ischemia. Precise function and regulation of intracellular EMAP II, however, has not been explored to date.Here we show that high intracellular EMAP II suppresses cellular proliferation by slowing progression through the G2M cell cycle transition in epithelium and fibroblast. Furthermore, EMAP II binds to and is phosphorylated by Cdk1, and exhibits nuclear/cytoplasmic partitioning, with only nuclear EMAP II being phosphorylated. We observed that extracellular secreted EMAP II induces endothelial cell apoptosis, where as excess intracellular EMAP II facilitates epithelial and fibroblast cells migration.Our findings suggest that EMAP II has specific intracellular effects, and that this intracellular function appears to antagonize its extracellular anti-angiogenic effects during fetal development and pulmonary disease progression.

  9. Hypothalamic peroxisome proliferator-activated receptor gamma regulates ghrelin production and food intake.

    Science.gov (United States)

    Li, Qingjie; Yu, Quan; Lin, Li; Zhang, Heng; Peng, Miao; Jing, Chunxia; Xu, Geyang

    2018-04-09

    Peroxisome proliferator-activated receptor-γ (PPARγ) regulates fatty acid storage, glucose metabolism, and food intake. Ghrelin, a gastric hormone, provides a hunger signal to the central nervous system to stimulate appetite. However, the effects of PPARγ on ghrelin production are still unclear. In the present study, the effects of PPARγ on ghrelin production were examined in lean- or high-fat diet-induced obese (DIO) C57BL/6J mice and mHypoE-42 cells, a hypothalamic cell line. 3rd intracerebroventricular injection of adenoviral-directed overexpression of PPARγ (Ad-PPARγ) reduced hypothalamic and plasma ghrelin, food intake in both lean C57BL/6J mice and diet-induced obese mice. These changes were associated with a significant increase in mechanistic target of rapamycin complex 1 (mTORC1) activity. Overexpression of PPARγ enhanced mTORC1 signaling and suppressed ghrelin production in cultured mHypoE-42 cells. Our results suggest that hypothalamic PPARγ plays a vital role in ghrelin production and food intake in mice. Copyright © 2018 Elsevier Ltd. All rights reserved.

  10. Liver X receptor and peroxisome proliferator-activated receptor as integrators of lipid homeostasis and immunity.

    Science.gov (United States)

    Kidani, Yoko; Bensinger, Steven J

    2012-09-01

    Lipid metabolism has emerged as an important modulator of innate and adaptive immune cell fate and function. The lipid-activated transcription factors peroxisome proliferator-activated receptor (PPAR) α, β/δ, γ and liver X receptor (LXR) are members of the nuclear receptor superfamily that have a well-defined role in regulating lipid homeostasis and metabolic diseases. Accumulated evidence over the last decade indicates that PPAR and LXR signaling also influence multiple facets of inflammation and immunity, thereby providing important crosstalk between metabolism and immune system. Herein, we provide a brief introduction to LXR and PPAR biology and review recent discoveries highlighting the importance of PPAR and LXR signaling in the modulation of normal and pathologic states of immunity. We also examine advances in our mechanistic understanding of how nuclear receptors impact immune system function and homeostasis. Finally, we discuss whether LXRs and PPARs could be pharmacologically manipulated to provide novel therapeutic approaches for modulation of the immune system under pathologic inflammation or in the context of allergic and autoimmune disease. © 2012 John Wiley & Sons A/S.

  11. Hedgehog signaling activation induces stem cell proliferation and hormone release in the adult pituitary gland.

    Science.gov (United States)

    Pyczek, Joanna; Buslei, Rolf; Schult, David; Hölsken, Annett; Buchfelder, Michael; Heß, Ina; Hahn, Heidi; Uhmann, Anja

    2016-04-25

    Hedgehog (HH) signaling is known to be essential during the embryonal development of the pituitary gland but the knowledge about its role in the adult pituitary and in associated tumors is sparse. In this report we investigated the effect of excess Hh signaling activation in murine pituitary explants and analyzed the HH signaling status of human adenopituitary lobes and a large cohort of pituitary adenomas. Our data show that excess Hh signaling led to increased proliferation of Sox2(+) and Sox9(+) adult pituitary stem cells and to elevated expression levels of adrenocorticotropic hormone (Acth), growth hormone (Gh) and prolactin (Prl) in the adult gland. Inhibition of the pathway by cyclopamine reversed these effects indicating that active Hh signaling positively regulates proliferative processes of adult pituitary stem cells and hormone production in the anterior pituitary. Since hormone producing cells of the adenohypophysis as well as ACTH-, GH- and PRL-immunopositive adenomas express SHH and its target GLI1, we furthermore propose that excess HH signaling is involved in the development/maintenance of hormone-producing pituitary adenomas. These findings advance the understanding of physiological hormone regulation and may open new treatment options for pituitary tumors.

  12. Structural insights into human peroxisome proliferator activated receptor delta (PPAR-delta selective ligand binding.

    Directory of Open Access Journals (Sweden)

    Fernanda A H Batista

    Full Text Available Peroxisome proliferator activated receptors (PPARs δ, α and γ are closely related transcription factors that exert distinct effects on fatty acid and glucose metabolism, cardiac disease, inflammatory response and other processes. Several groups developed PPAR subtype specific modulators to trigger desirable effects of particular PPARs without harmful side effects associated with activation of other subtypes. Presently, however, many compounds that bind to one of the PPARs cross-react with others and rational strategies to obtain highly selective PPAR modulators are far from clear. GW0742 is a synthetic ligand that binds PPARδ more than 300-fold more tightly than PPARα or PPARγ but the structural basis of PPARδ:GW0742 interactions and reasons for strong selectivity are not clear. Here we report the crystal structure of the PPARδ:GW0742 complex. Comparisons of the PPARδ:GW0742 complex with published structures of PPARs in complex with α and γ selective agonists and pan agonists suggests that two residues (Val312 and Ile328 in the buried hormone binding pocket play special roles in PPARδ selective binding and experimental and computational analysis of effects of mutations in these residues confirms this and suggests that bulky substituents that line the PPARα and γ ligand binding pockets as structural barriers for GW0742 binding. This analysis suggests general strategies for selective PPARδ ligand design.

  13. Phosphatidylinositol response and proliferation of oxidative enzyme-activated human T lymphocytes: suppression by plasma lipoproteins

    International Nuclear Information System (INIS)

    Akeson, A.L.; Scupham, D.W.; Harmony, J.A.

    1984-01-01

    The phosphatidylinositol (PI) response and DNA synthesis of neuraminidase and galactose oxidase (NAGO)-stimulated human T lymphocytes are suppressed by low density lipoproteins (LDL). To understand the mechanism of lymphocyte activation more fully, the PI response and DNA synthesis and suppression of these events by LDL in NAGO-stimulated T lymphocytes were characterized. Between 30 min and 6 hr after NAGO stimulation, there was an increase of 32 Pi incorporation into PI without increased incorporation into the phosphorylated forms of PI or into other phospholipids. DNA synthesis as determined by [ 3 H]thymidine incorporation depended on the lymphocyte-accessory monocyte ratio and total cell density. Optimal stimulation of the PI response and DNA synthesis occurred at the same concentration of neuraminidase and galactose oxidase. While the PI response was only partially suppressed by LDL with optimal suppression at 10 to 20 micrograms of protein/ml, DNA synthesis was completely suppressed although at much higher LDL concentrations, greater than 100 micrograms protein/ml. As monocyte numbers are increased, LDL suppression of DNA synthesis is decreased. The ability of NAGO to stimulate the PI response and DNA synthesis in a similar way, and the suppression of both events by LDL, suggests the PI response is important for lymphocyte activation and proliferation. Stimulation of human T lymphocytes by oxidative mitogens, neuraminidase, and galactose oxidase caused increased phosphatidylinositol metabolism and increased DNA synthesis. Both responses were suppressed by low density lipoproteins

  14. Structural characteristics of pineapple pulp polysaccharides and their antitumor cell proliferation activities.

    Science.gov (United States)

    Wang, Ling; Tang, De-Qiang; Kuang, Yu; Lin, Feng-Jiao; Su, Yu

    2015-09-01

    Pineapple has a delicious taste and good health benefits. Bioactive polysaccharides are important components of pineapple that might contribute to its health benefits. Since little structural information on these polysaccharides is currently available, the aim of this study was to investigate their structural characteristics and bioactivities. The polysaccharides of pineapple pulp were fractionated into three fractions (PAPs 1-3) by anion exchange chromatography. Their structural characteristics were first identified, including molecular weights and glycosidic linkages. The monosaccharide compositions were revealed as PAP 1 (Ara, Xyl, Man, Glc and Gal), PAP 2 (Rha, Ara, Xyl, Man, Glc and Gal) and PAP 3 (Rha, Ara, Xyl, Man and Gal). Nuclear magnetic resonance (NMR) spectra suggested that PAP 2 had a backbone of → 4)-α-d-Manp-(1 → 2,4)-α-d-Manp-(1 → with branches attached to O-4 of Manp. The NMR data of α-l-Araf-(1→, →3)-α-l-Araf-(1→, →4)-β-d-Galp-(1 → and → 4)-α-d-GalpAMe-(1 → were assigned. PAPs 1 and 2 showed significant antitumor cell proliferation activities against breast carcinoma cell line and strong antioxidant activities. The above findings indicated that PAPs 1-3 contributed much to the health benefits of pineapple. They could be used as health-beneficial food additives in functional foods. © 2015 Society of Chemical Industry.

  15. Platelet lysate activates quiescent cell proliferation and reprogramming in human articular cartilage: Involvement of hypoxia inducible factor 1.

    Science.gov (United States)

    Nguyen, Van Thi; Cancedda, Ranieri; Descalzi, Fiorella

    2018-03-01

    The idea of rescuing the body self-repair capability lost during evolution is progressively gaining ground in regenerative medicine. In particular, growth factors and bioactive molecules derived from activated platelets emerged as promising therapeutic agents acting as trigger for repair of tissue lesions and restoration of tissue functions. Aim of this study was to assess the potential of a platelet lysate (PL) for human articular cartilage repair considering its activity on progenitor cells and differentiated chondrocytes. PL induced the re-entry in the cell cycle of confluent, growth-arrested dedifferentiated/progenitor cartilage cells. In a cartilage permissive culture environment, differentiated cells also resumed proliferation after exposure to PL. These findings correlated with an up-regulation of the proliferation/survival pathways ERKs and Akt and with an induction of cyclin D1. In short- and long-term cultures of articular cartilage explants, we observed a release of proliferating chondroprogenitors able to differentiate and form an "in vitro" tissue with properties of healthy articular cartilage. Moreover, in cultured cartilage cells, PL induced a hypoxia-inducible factor (HIF-1) alpha increase, its nuclear relocation and the binding to HIF-1 responsive elements. These events were possibly related to the cell proliferation because the HIF-1 inhibitor acriflavine inhibited HIF-1 binding to HIF-1 responsive elements and cell proliferation. Our study demonstrates that PL induces quiescent cartilage cell activation and proliferation leading to new cartilage formation, identifies PL activated pathways playing a role in these processes, and provides a rationale to the application of PL for therapeutic treatment of damaged articular cartilage. Copyright © 2017 John Wiley & Sons, Ltd.

  16. Activation of peroxisome proliferator-activated receptor-alpha and -gamma in auricular tissue from heart failure patients.

    Science.gov (United States)

    Gómez-Garre, Dulcenombre; Herraíz, Marta; González-Rubio, Ma Luisa; Bernal, Rosa; Aragoncillo, Paloma; Carbonell, Amparo; Rufilanchas, Juan José; Fernández-Cruz, Arturo

    2006-03-01

    Peroxisome proliferator-activated receptors (PPARs), key transcriptional regulators of lipid and energy metabolism in cardiomyocytes, have recently been proposed to modulate cardiovascular pathophysiological responses in experimental models. However, there is little information about the functional activity of PPARs in human heart failure. To investigate PPAR-alpha and -gamma expression and activity, and the association with ET-1 production and fibrosis, in cardiac biopsies from patients with end-stage heart failure due to ischemic cardiomyopathy (ICM) in comparison and from non-failing donor hearts. All samples were obtained during cardiac transplantation. Morphological analysis (by Masson trichrome and image analysis) did not detect fibrosis in the left atrium from non-failing donors (NFLA) or from ICM patients (FLA). However, left ventricles from failing hearts (FLV) contained a greater number of fibrotic areas (NFLA: 3.21+/-1.15, FLA: 1.63+/-0.83, FLV: 14.5+/-3.45%; n = 9, PPPAP-gamma mRNA (by RT-PCR) and protein (by Western blot) levels were higher in the ventricles from failing hearts compared with the atrium from failing and non-failing hearts. Electrophoretic mobility shift assays showed that PPAR-alpha and PPAP-gamma were not activated in the ventricles (NFLA: 1.00+/-0.11, FLA: 1.89+/-0.24, FLV: 0.95+/-0.07; n = 9, PPPAP-gamma are selectively activated in the atria from ICM patients and might be functionally important in the maintenance of atrial morphology.

  17. Gemfibrozil, a lipid lowering drug, inhibits the activation of primary human microglia via peroxisome proliferator-activated receptor β.

    Science.gov (United States)

    Jana, Malabendu; Pahan, Kalipada

    2012-08-01

    Microglial activation participates in the pathogenesis of various neuroinflammatory and neurodegenerative diseases. However, mechanisms by which microglial activation could be controlled are poorly understood. Peroxisome proliferator-activated receptors (PPAR) are transcription factors belonging to the nuclear receptor super family with diverse effect. This study underlines the importance of PPARβ/δ in mediating the anti-inflammatory effect of gemfibrozil, an FDA-approved lipid-lowering drug, in primary human microglia. Bacterial lipopolysachharides (LPS) induced the expression of various proinflammatory molecules and upregulated the expression of microglial surface marker CD11b in human microglia. However, gemfibrozil markedly suppressed proinflammatory molecules and CD11b in LPS-stimulated microglia. Human microglia expressed PPAR-β and -γ, but not PPAR-α. Interestingly, either antisense knockdown of PPAR-β or antagonism of PPAR-β by a specific chemical antagonist abrogated gemfibrozil-mediated inhibition of microglial activation. On the other hand, blocking of PPAR-α and -γ had no effect on gemfibrozil-mediated anti-inflammatory effect in microglia. These results highlight the fact that gemfibrozil regulates microglial activation by inhibiting inflammatory gene expression in a PPAR-β dependent pathway and further reinforce its therapeutic application in several neuroinflammatory and neurodegenerative diseases.

  18. Role of the peroxisome proliferator-activated receptor α in responses to diisononyl phthalate

    International Nuclear Information System (INIS)

    Valles, Edith G.; Laughter, Ashley R.; Dunn, Corrie S.; Cannelle, Sabine; Swanson, Cynthia L.; Cattley, Russell C.; Corton, J. Christopher

    2003-01-01

    Diisononyl phthalate (DINP) is a compound widely used as a plasticizer in the production of polyvinyl chloride products. Chronic exposure to DINP leads to liver cancer in rats and mice. Many phthalates are considered to be relatively weak peroxisome proliferators (PP), a group of rodent hepatocarcinogens that cause a variety of adaptive responses in liver through the PP-activated receptor alpha (PPARα). The objectives of this study were to determine whether DINP-induced effects in the liver associated with carcinogenesis are mediated by PPARα and to identify novel gene targets of DINP. Male and female SV129 wild-type, SV129 PPARα-null, and B6C3F1 mice were administered DINP by gavage or in the feed. Transcript profile technology and reverse transcriptase (RT)-polymerase chain reaction (PCR) were used to identify gene targets. Dose-dependent increases in relative liver weights were dependent on PPARα in 10- or 12-week-old male and female mice and 30-week-old male mice. Female 30-week-old mice exhibited PPARα-independent increases in relative liver weights. Increases in hepatocyte proliferation, palmitoyl-CoA oxidase (PCO) activity, and levels of enzymes involved in β- and ω-oxidation of fatty acids were shown to be dependent on PPARα. Five novel genes were shown to be altered in the livers of female wild-type mice after a 3-week exposure, but not in PPARα-null, mice. These genes included those involved in DNA repair and recombination (ATP-dependent helicase and Endonuclease III homolog), drug metabolism (Cyp2a4) and protein trafficking (FKBP-1, FKBP-13). An additional gene (Cyp2d9) was shown to be down-regulated in wild-type mice but up-regulated in PPARα-null mice indicating more complex regulation by PPARα and additional factors. These data support the hypothesis that PPARα plays a dominant role in mediating the effects associated with hepatocarcinogenesis after DINP exposure

  19. Zebrafish kidney phagocytes utilize macropinocytosis and Ca+-dependent endocytic mechanisms.

    Directory of Open Access Journals (Sweden)

    Claudia Hohn

    Full Text Available BACKGROUND: The innate immune response constitutes the first line of defense against invading pathogens and consists of a variety of immune defense mechanisms including active endocytosis by macrophages and granulocytes. Endocytosis can be used as a reliable measure of selective and non-selective mechanisms of antigen uptake in the early phase of an immune response. Numerous assays have been developed to measure this response in a variety of mammalian and fish species. The small size of the zebrafish has prevented the large-scale collection of monocytes/macrophages and granulocytes for these endocytic assays. METHODOLOGY/PRINCIPAL FINDINGS: Pooled zebrafish kidney hematopoietic tissues were used as a source of phagocytic cells for flow-cytometry based endocytic assays. FITC-Dextran, Lucifer Yellow and FITC-Edwardsiella ictaluri were used to evaluate selective and non-selective mechanisms of uptake in zebrafish phagocytes. CONCLUSIONS/SIGNIFICANCE: Zebrafish kidney phagocytes characterized as monocytes/macrophages, neutrophils and lymphocytes utilize macropinocytosis and Ca(2+-dependant endocytosis mechanisms of antigen uptake. These cells do not appear to utilize a mannose receptor. Heat-killed Edwardsiella ictaluri induces cytoskeletal interactions for internalization in zebrafish kidney monocytes/macrophages and granulocytes. The proposed method is easy to implement and should prove especially useful in immunological, toxicological and epidemiological research.

  20. Molecular pharmacology of antihistamines in inhibition of oxidative burst of professional phagocytes.

    Science.gov (United States)

    Nosáľ, Radomír; Jančinová, Viera; Drábiková, Katarína; Perečko, Tomáš

    2015-04-01

    Antihistamines of the H₁and H₃/H₄groups interfere with oxidative burst of human professional phagocytes in vitro. In the concentration of 10 μM, H₁antihistamines of the 1st and 2nd generation inhibited oxidative burst of human neutrophils in the rank order of potency: dithiaden > loratadine > brompheniramine > chlorpheniramine > pheniramine. Of the H₁antihistamines, the most effective was dithiaden in suppressing oxidative burst of whole human blood and dose-dependently the chemiluminescence of isolated neutrophils at extra- and intracellular level. Inhibition of free oxygen radical generation in isolated neutrophils by dithiaden resulted from the inhibition of protein kinase C activation. The potentiation of recombinant caspase-3 by dithiaden is supportive of the antiinflammatory effect of dithiaden and suggestive of increasing the apoptosis of professional phagocytes. Of the H₃/H₄antihistamines, the most effective was JNJ7777120 in decreasing chemiluminescence in whole blood and also at extra- and intracellular sites of isolated neutrophils. JNJ 10191584 and thioperamide were less effective and the latter significantly potentiated free oxygen radical generation intracellularly. The results demonstrated that, compared with the H₃/H₄antihistamines investigated, H₁antihistamines were much more potent in inhibiting free oxygen radical generation in human professional phagocytes. This finding should be taken into account therapeutically.

  1. Increased renin production in mice with deletion of peroxisome proliferator-activated receptor-gamma in juxtaglomerular cells

    DEFF Research Database (Denmark)

    Desch, Michael; Schreiber, Andrea; Schweda, Frank

    2010-01-01

    We recently found that endogenous (free fatty acids) and pharmacological (thiazolidinediones) agonists of nuclear receptor Peroxisome proliferator-activated receptor (PPAR)gamma stimulate renin transcription. In addition, the renin gene was identified as a direct target of PPARgamma. The mouse re...

  2. GQ-16, a Novel Peroxisome Proliferator-activated Receptor gamma (PPAR gamma) Ligand, Promotes Insulin Sensitization without Weight Gain

    NARCIS (Netherlands)

    Amato, Angelica A.; Rajagopalan, Senapathy; Lin, Jean Z.; Carvalho, Bruno M.; Figueira, Ana C. M.; Lu, Jenny; Ayers, Stephen D.; Mottin, Melina; Silveira, Rodrigo L.; Telles de Souza, Paulo; Mourao, Rosa H. V.; Saad, Mario J. A.; Togashi, Marie; Simeoni, Luiz A.; Abdalla, Dulcineia S. P.; Skaf, Munir S.; Polikparpov, Igor; Lima, Maria C. A.; Galdino, Suely L.; Brennan, Richard G.; Baxter, John D.; Pitta, Ivan R.; Webb, Paul; Phillips, Kevin J.; Neves, Francisco A. R.

    2012-01-01

    The recent discovery that peroxisome proliferator-activated receptor gamma (PPAR gamma) targeted anti-diabetic drugs function by inhibiting Cdk5-mediated phosphorylation of the receptor has provided a new viewpoint to evaluate and perhaps develop improved insulin-sensitizing agents. Herein we report

  3. The Peroxisome Proliferator-Activated Receptor α is dispensable for cold-induced adipose tissue browning in mice

    NARCIS (Netherlands)

    Defour, Merel; Dijk, Wieneke; Ruppert, Philip; Nascimento, Emmani B.M.; Schrauwen, Patrick; Kersten, Sander

    2018-01-01

    Objective: Chronic cold exposure causes white adipose tissue (WAT) to adopt features of brown adipose tissue (BAT), a process known as browning. Previous studies have hinted at a possible role for the transcription factor Peroxisome Proliferator-Activated Receptor alpha (PPARα) in cold-induced

  4. Potential effects of curcumin on peroxisome proliferator-activated receptor-gamma in vitro and in vivo

    Science.gov (United States)

    Natural peroxisome proliferator-activated receptor-gamma (PPAR-gamma) agonists are found in food and may be important for health through their anti-inflammatory properties. Curcumin (Cur) is a bright yellow spice, derived from the rhizome of Curcuma longa Linn. It has been shown to have many biologi...

  5. Id1 expression promotes peripheral CD4{sup +} T cell proliferation and survival upon TCR activation without co-stimulation

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Chen; Jin, Rong [Department of Immunology, Peking University Health Science Center, Beijing (China); Wang, Hong-Cheng [Oklahoma Medical Research Foundation, Oklahoma City, OK (United States); Tang, Hui; Liu, Yuan-Feng; Qian, Xiao-Ping; Sun, Xiu-Yuan; Ge, Qing [Department of Immunology, Peking University Health Science Center, Beijing (China); Sun, Xiao-Hong, E-mail: sunx@omrf.org [Oklahoma Medical Research Foundation, Oklahoma City, OK (United States); Zhang, Yu, E-mail: zhangyu007@bjmu.edu.cn [Department of Immunology, Peking University Health Science Center, Beijing (China)

    2013-06-21

    Highlights: •Id1 expression enables naïve T cell proliferation without anti-CD28 co-stimulation. •Id1 expression facilitates T cells survival when stimulated with anti-CD3. •Elevation of IL-2 production by Id1 contributes increased proliferation and survival. •Id1 potentiates NF-κB activation by anti-CD3 stimulation. -- Abstract: Although the role of E proteins in the thymocyte development is well documented, much less is known about their function in peripheral T cells. Here we demonstrated that CD4 promoter-driven transgenic expression of Id1, a naturally occurring dominant-negative inhibitor of E proteins, can substitute for the co-stimulatory signal delivered by CD28 to facilitate the proliferation and survival of naïve CD4{sup +} cells upon anti-CD3 stimulation. We next discovered that IL-2 production and NF-κB activity after anti-CD3 stimulation were significantly elevated in Id1-expressing cells, which may be, at least in part, responsible for the augmentation of their proliferation and survival. Taken together, results from this study suggest an important role of E and Id proteins in peripheral T cell activation. The ability of Id proteins to by-pass co-stimulatory signals to enable T cell activation has significant implications in regulating T cell immunity.

  6. More efficient integrated safeguards by applying a reasonable detection probability for maintaining low presence probability of undetected nuclear proliferating activities

    International Nuclear Information System (INIS)

    Otsuka, Naoto

    2013-01-01

    Highlights: • A theoretical foundation is presented for more efficient Integrated Safeguards (IS). • Probability of undetected nuclear proliferation activities should be maintained low. • For nations under IS, the probability to start proliferation activities is very low. • The fact can decrease the detection probability of IS by dozens of percentage points. • The cost of IS per nation can be cut down by reducing inspection frequencies etc. - Abstract: A theoretical foundation is presented for implementing more efficiently the present International Atomic Energy Agency (IAEA) integrated safeguards (ISs) on the basis of fuzzy evaluation of the probability that the evaluated nation will continue peaceful activities. It is shown that by determining the presence probability of undetected nuclear proliferating activities, nations under IS can be maintained at acceptably low proliferation risk levels even if the detection probability of current IS is decreased by dozens of percentage from the present value. This makes it possible to reduce inspection frequency and the number of collected samples, allowing the IAEA to cut costs per nation. This will contribute to further promotion and application of IS to more nations by the IAEA, and more efficient utilization of IAEA resources from the viewpoint of whole IS framework

  7. Peroxisome proliferator-activated receptor-gamma (PPARgamma) Pro12Ala polymorphism and risk for pediatric obesity

    NARCIS (Netherlands)

    Dedoussis, George V; Vidra, Nikoleta; Butler, Johannah; Papoutsakis, Constantina; Yannakoulia, Mary; Hirschhorn, Joel N; Lyon, Helen N; Vidra, Nikoletta

    BACKGROUND: Variation in the peroxisome-proliferator-activated receptor gamma (PPARgamma) gene has been reported to alter the risk for adiposity in adults. METHODS: We investigated the gender related association between the Pro12Ala variant (rs1801282) in obesity and insulin resistance traits in 794

  8. Peroxisome Proliferator-Activated Receptor α Activation Suppresses Cytochrome P450 Induction Potential in Mice Treated with Gemfibrozil.

    Science.gov (United States)

    Shi, Cunzhong; Min, Luo; Yang, Julin; Dai, Manyun; Song, Danjun; Hua, Huiying; Xu, Gangming; Gonzalez, Frank J; Liu, Aiming

    2017-09-01

    Gemfibrozil, a peroxisome proliferator-activated receptor α (PPARα) agonist, is widely used for hypertriglyceridaemia and mixed hyperlipidaemia. Drug-drug interaction of gemfibrozil and other PPARα agonists has been reported. However, the role of PPARα in cytochrome P450 (CYP) induction by fibrates is not well known. In this study, wild-type mice were first fed gemfibrozil-containing diets (0.375%, 0.75% and 1.5%) for 14 days to establish a dose-response relationship for CYP induction. Then, wild-type mice and Pparα-null mice were treated with a 0.75% gemfibrozil-containing diet for 7 days. CYP3a, CYP2b and CYP2c were induced in a dose-dependent manner by gemfibrozil. In Pparα-null mice, their mRNA level, protein level and activity were induced more than those in wild-type mice. So, gemfibrozil induced CYP, and this action was inhibited by activated PPARα. These data suggested that the induction potential of CYPs was suppressed by activated PPARα, showing a potential role of this receptor in drug-drug interactions and metabolic diseases treated with fibrates. © 2017 Nordic Association for the Publication of BCPT (former Nordic Pharmacological Society).

  9. Catalposide is a natural agonistic ligand of peroxisome proliferator-activated receptor-α

    International Nuclear Information System (INIS)

    Lee, Ji Hae; Jun, Hee-jin; Hoang, Minh-Hien; Jia, Yaoyao; Han, Xiang Hua; Lee, Dong-Ho; Lee, Hak-Ju; Hwang, Bang Yeon; Lee, Sung-Joon

    2012-01-01

    Highlights: ► Catalposide is a novel ligand for PPARα. ► Cell stimulated with catalposide improved fatty acid uptake, regulated target genes in fatty acid β-oxidation and synthesis. ► Catalposdie reduces hepatic triacylglycerides. ► Theses demonstrate catalposide could ameliorate hyperlipidemia and hepatic steatosis. -- Abstract: Peroxisome proliferator-activated receptor-alpha (PPARα) is a nuclear receptor that regulates the expression of genes related to cellular lipid uptake and oxidation. Thus, PPARα agonists may be important in the treatment of hypertriglyceridemia and hepatic steatosis. In this study, we demonstrated that catalposide is a novel natural PPARα agonist, identified from reporter gene assay-based activity screening with approximately 900 natural plant and seaweed extracts. Results of time-resolved fluorescence resonance energy transfer analyses suggested that the compound interacted directly with the ligand-binding domain of PPARα. Cultured hepatocytes stimulated with catalposide exhibited significantly reduced cellular triglyceride concentrations, by 21%, while cellular uptake of fatty acids was increased, by 70% (P < 0.05). Quantitative PCR analysis revealed that the increase in cellular fatty acid uptake was due to upregulation of fatty acid transporter protein-4 (+19% vs. the control) in cells stimulated with catalposide. Additionally, expression of genes related to fatty acid oxidation and high-density lipoprotein metabolism were upregulated, while that of genes related to fatty acid synthesis were suppressed. In conclusion, catalposide is hypolipidemic by activation of PPARα via a ligand-mediated mechanism that modulates the expression of in lipid metabolism genes in hepatocytes.

  10. Catalposide is a natural agonistic ligand of peroxisome proliferator-activated receptor-{alpha}

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ji Hae; Jun, Hee-jin; Hoang, Minh-Hien; Jia, Yaoyao [Division of Food Bioscience and Technology, College of Life Sciences and Biotechnology, Korea University, Seoul 136-713 (Korea, Republic of); Department of Biotechnology, Graduate School of Life Sciences and Biotechnology, Korea University, Seoul 136-713 (Korea, Republic of); Han, Xiang Hua [College of Pharmacy, Chungbuk National University, Cheongju, Chungbuk 361-763 (Korea, Republic of); Lee, Dong-Ho [Department of Biotechnology, Graduate School of Life Sciences and Biotechnology, Korea University, Seoul 136-713 (Korea, Republic of); Lee, Hak-Ju [Division of Green Business Management, Department of Forest Resources Utilization, Korean Forest Research Institute, Seoul 130-712 (Korea, Republic of); Hwang, Bang Yeon, E-mail: byhwang@chungbuk.ac.kr [College of Pharmacy, Chungbuk National University, Cheongju, Chungbuk 361-763 (Korea, Republic of); Lee, Sung-Joon, E-mail: junelee@korea.ac.kr [Division of Food Bioscience and Technology, College of Life Sciences and Biotechnology, Korea University, Seoul 136-713 (Korea, Republic of); Department of Biotechnology, Graduate School of Life Sciences and Biotechnology, Korea University, Seoul 136-713 (Korea, Republic of)

    2012-06-15

    Highlights: Black-Right-Pointing-Pointer Catalposide is a novel ligand for PPAR{alpha}. Black-Right-Pointing-Pointer Cell stimulated with catalposide improved fatty acid uptake, regulated target genes in fatty acid {beta}-oxidation and synthesis. Black-Right-Pointing-Pointer Catalposdie reduces hepatic triacylglycerides. Black-Right-Pointing-Pointer Theses demonstrate catalposide could ameliorate hyperlipidemia and hepatic steatosis. -- Abstract: Peroxisome proliferator-activated receptor-alpha (PPAR{alpha}) is a nuclear receptor that regulates the expression of genes related to cellular lipid uptake and oxidation. Thus, PPAR{alpha} agonists may be important in the treatment of hypertriglyceridemia and hepatic steatosis. In this study, we demonstrated that catalposide is a novel natural PPAR{alpha} agonist, identified from reporter gene assay-based activity screening with approximately 900 natural plant and seaweed extracts. Results of time-resolved fluorescence resonance energy transfer analyses suggested that the compound interacted directly with the ligand-binding domain of PPAR{alpha}. Cultured hepatocytes stimulated with catalposide exhibited significantly reduced cellular triglyceride concentrations, by 21%, while cellular uptake of fatty acids was increased, by 70% (P < 0.05). Quantitative PCR analysis revealed that the increase in cellular fatty acid uptake was due to upregulation of fatty acid transporter protein-4 (+19% vs. the control) in cells stimulated with catalposide. Additionally, expression of genes related to fatty acid oxidation and high-density lipoprotein metabolism were upregulated, while that of genes related to fatty acid synthesis were suppressed. In conclusion, catalposide is hypolipidemic by activation of PPAR{alpha} via a ligand-mediated mechanism that modulates the expression of in lipid metabolism genes in hepatocytes.

  11. Cell surface GRP78 facilitates hepatoma cells proliferation and migration by activating IGF-IR.

    Science.gov (United States)

    Yin, Yancun; Chen, Chen; Chen, Jinliang; Zhan, Renhui; Zhang, Qiang; Xu, Xiaoyan; Li, Defang; Li, Minjing

    2017-07-01

    The 78kDa glucose regulated protein (GRP78) is a multifunctional chaperone that is involved in a variety of cellular processes. Insulin like growth factor I receptor (IGF-IR) often aberrant expresses in many types of tumor cells. The IGF-IR signaling plays key roles in carcinogenesis and maintenance of the malignant phenotype. The crosstalk between GRP78 and IGF-IR molecules has not well been illuminated. Here, we demonstrated a reciprocal regulation of GRP78 expression and IGF-IR pathway activation. IGF-I induced GRP78 expression in hepatoma cells. IGF-IR knockdown or IGF-IR inhibitor repressed GRP78 expression. Both phosphatidylinositol 3-kianase (PI3K) and mitogen-activated protein kinase (MAPK) pathways involved in IGF-I induction of GRP78 expression. Interestingly, treatment of hepatoma cells with IGF-I re-distributes GRP78 from endoplasmic reticulum (ER) to cell surface and promotes its physical interaction with IGF-IR. Also, GRP78 promotes IGF-IR phosphorylation and activation. Blocked of GRP78 by small interfering RNA or inhibition of GRP78 function by (-)-epigallocatechin gallate (EGCG) blocks IGF-I induced IGF-IR phosphorylation and its downstream signaling. Further, blocked cell surface GRP78 with antibody inhibits IGF-I stimulated cellular proliferation and migration. These data reveal an essential role for the molecular chaperone GRP78 in IGF-IR signaling and implicate the use of GRP78 inhibitors in blocking IGF-IR signaling in hepatoma cells. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Peroxisome proliferator-activated receptors: bridging metabolic syndrome with molecular nutrition.

    Science.gov (United States)

    Guri, Amir J; Hontecillas, Raquel; Bassaganya-Riera, Josep

    2006-12-01

    Over recent years, obesity rates and the onset of obesity-induced chronic diseases have risen dramatically. The more we learn about the physiological and morphological changes that occur during obesity, the more it is becoming clear that obesity-related disorders can be traced back to adipocyte hypertrophy and inflammation at white adipose tissue (WAT). To combat this problem, the body has developed a regulatory system specifically designed at mediating the systemic response to obesity, utilizing free fatty acids (FFAs) and their metabolites as nutrient messengers to signal adaptations from peripheral tissues. These messages are predominantly interceded through the peroxisome proliferator-activated receptors (PPARs), a family of ligand-induced transcription factors that serve as a net of lipid sensors throughout the body. Understanding how and why nutrients, nutrient derivatives and metabolites exert their physiological effects are the key goals in the study of molecular nutrition. By learning about the mechanisms and tissue-specific effects of endogenous PPAR ligands and expanding our knowledge of the body's integrated homeostatic system, we will significantly increase our odds of designing safe and effective preventive and therapeutic interventions that keep us one step ahead of obesity-related diseases.

  13. Peroxisome Proliferator-Activated Receptor Gamma in Obesity and Colorectal Cancer: the Role of Epigenetics.

    Science.gov (United States)

    Motawi, T K; Shaker, O G; Ismail, M F; Sayed, N H

    2017-09-06

    Peroxisome proliferator-activated receptor gamma (PPARγ) is a nuclear receptor that is deregulated in obesity. PPARγ exerts diverse antineoplastic effects. Attempting to determine the clinical relevance of the epigenetic mechanisms controlling the expression PPARγ and susceptibility to colorectal cancer (CRC) in obese subjects, this study investigated the role of some microRNAs and DNA methylation on the deregulation of PPARγ. Seventy CRC patients (34 obese and 36 lean), 22 obese and 24 lean healthy controls were included. MicroRNA levels were measured in serum. PPARγ promoter methylation was evaluated in peripheral blood mononuclear cells (PBMC). PPARγ level was evaluated by measuring mRNA level in PBMC and protein level in serum. The tested microRNAs (miR-27b, 130b and 138) were significantly upregulated in obese and CRC patients. Obese and CRC patients had significantly low levels of PPARγ. A significant negative correlation was found between PPARγ levels and the studied microRNAs. There was a significant PPARγ promoter hypermethylation in CRC patients that correlated to low PPARγ levels. Our results suggest that upregulation of microRNAs 27b, 130b and 138 is associated with susceptibility to CRC in obese subjects through PPARγ downregulation. Hypermethylation of PPARγ gene promoter is associated with CRC through suppression of PPARγ regardless of BMI.

  14. Discovery of an Oxybenzylglycine Based Peroxisome Proliferator Activated Receptor Alpha Selective

    Energy Technology Data Exchange (ETDEWEB)

    Li, J.; Kennedy, L; Shi, Y; Tao, S; Ye, X; Chen, S; Wang, Y; Hernandez, A; Wang, W; et al.

    2010-01-01

    An 1,3-oxybenzylglycine based compound 2 (BMS-687453) was discovered to be a potent and selective peroxisome proliferator activated receptor (PPAR) {alpha} agonist, with an EC{sub 50} of 10 nM for human PPAR{alpha} and {approx}410-fold selectivity vs human PPAR{gamma} in PPAR-GAL4 transactivation assays. Similar potencies and selectivity were also observed in the full length receptor co-transfection assays. Compound 2 has negligible cross-reactivity against a panel of human nuclear hormone receptors including PPAR{delta}. Compound 2 demonstrated an excellent pharmacological and safety profile in preclinical studies and thus was chosen as a development candidate for the treatment of atherosclerosis and dyslipidemia. The X-ray cocrystal structures of the early lead compound 12 and compound 2 in complex with PPAR{alpha} ligand binding domain (LBD) were determined. The role of the crystal structure of compound 12 with PPAR{alpha} in the development of the SAR that ultimately resulted in the discovery of compound 2 is discussed.

  15. Zizyphus lotus L. (Desf. modulates antioxidant activity and human T-cell proliferation

    Directory of Open Access Journals (Sweden)

    Belarbi Meriem

    2010-09-01

    Full Text Available Abstract Background Zizyphus lotus L. (Desf. also known as Jujube, is a deciduous shrub which belongs to Rhamnaceae family. This plant is used in Algerian traditional medicine for its anti-diabetic, sedative, analgesic, anti-inflammatory and hypoglycaemic activities. In the present study, we determined the concentrations of different vitamins (vitamin A, C and E and fatty acids in root, stem, leaves, fruit pulp and seed of Zizyphus lotus L. (Desf. and assessed the effects of their aqueous extracts on antioxidant status and human T-cell proliferation. Methods Aqueous filtrates from different parts, i.e, root, leaf, stem, fruit pulp and seed, of Zizyphus lotus L. (Desf. were prepared. Vitamin C levels were determined by precipitating with 10% trichloroacetic acid and vitamin A and E were assessed by HPLC. Lipid composition of these extracts was determined by gas-liquid chromatography. Anti-oxidant capacity was evaluated by using anti-radical resistance kit [Kit Radicaux Libres (KRL@; Kirial International SA, Couternon, France]. T-cell blastogenesis was assessed by the incorporation of 3H-thymidine. IL-2 gene expression was evaluated by RT-qPCR. Results Our results show that fruit pulp contained higher vitamin A and C contents than other parts of the plant. Furthermore, the fruit pulp was the richest source of linoleic acid (18:2n-6, a precursor of n-6 fatty acids. Fruit seeds possessed higher vitamin C levels than leaves, roots and stem. The leaves were the richest source of vitamin E and linolenic acid (18:3n-3, a precursor of n-3 fatty acids. The antioxidant capacity of the different extracts, measured by KRL@ test, was as follows: pulp Zizyphus lotus L. (Desf. exerted immunosuppressive effects. Conclusion Seed extracts exerted the most potent immunosuppressive effects on T cell proliferation and IL-2 mRNA expression. The results of the present study are discussed in the light of their use to modulate the immune-mediated diseases.

  16. Orphan nuclear receptor TLX activates Wnt/β-catenin signalling to stimulate neural stem cell proliferation and self-renewal

    Science.gov (United States)

    Qu, Qiuhao; Sun, Guoqiang; Li, Wenwu; Yang, Su; Ye, Peng; Zhao, Chunnian; Yu, Ruth T.; Gage, Fred H.; Evans, Ronald M.; Shi, Yanhong

    2010-01-01

    The nuclear receptor TLX (also known as NR2E1) is essential for adult neural stem cell self-renewal; however, the molecular mechanisms involved remain elusive. Here we show that TLX activates the canonical Wnt/β-catenin pathway in adult mouse neural stem cells. Furthermore, we demonstrate that Wnt/β-catenin signalling is important in the proliferation and self-renewal of adult neural stem cells in the presence of epidermal growth factor and fibroblast growth factor. Wnt7a and active β-catenin promote neural stem cell self-renewal, whereas the deletion of Wnt7a or the lentiviral transduction of axin, a β-catenin inhibitor, led to decreased cell proliferation in adult neurogenic areas. Lentiviral transduction of active β-catenin led to increased numbers of type B neural stem cells in the subventricular zone of adult brains, whereas deletion of Wnt7a or TLX resulted in decreased numbers of neural stem cells retaining bromodeoxyuridine label in the adult brain. Both Wnt7a and active β-catenin significantly rescued a TLX (also known as Nr2e1) short interfering RNA-induced deficiency in neural stem cell proliferation. Lentiviral transduction of an active β-catenin increased cell proliferation in neurogenic areas of TLX-null adult brains markedly. These results strongly support the hypothesis that TLX acts through the Wnt/β-catenin pathway to regulate neural stem cell proliferation and self-renewal. Moreover, this study suggests that neural stem cells can promote their own self-renewal by secreting signalling molecules that act in an autocrine/paracrine mode. PMID:20010817

  17. Orphan nuclear receptor TLX activates Wnt/beta-catenin signalling to stimulate neural stem cell proliferation and self-renewal.

    Science.gov (United States)

    Qu, Qiuhao; Sun, Guoqiang; Li, Wenwu; Yang, Su; Ye, Peng; Zhao, Chunnian; Yu, Ruth T; Gage, Fred H; Evans, Ronald M; Shi, Yanhong

    2010-01-01

    The nuclear receptor TLX (also known as NR2E1) is essential for adult neural stem cell self-renewal; however, the molecular mechanisms involved remain elusive. Here we show that TLX activates the canonical Wnt/beta-catenin pathway in adult mouse neural stem cells. Furthermore, we demonstrate that Wnt/beta-catenin signalling is important in the proliferation and self-renewal of adult neural stem cells in the presence of epidermal growth factor and fibroblast growth factor. Wnt7a and active beta-catenin promote neural stem cell self-renewal, whereas the deletion of Wnt7a or the lentiviral transduction of axin, a beta-catenin inhibitor, led to decreased cell proliferation in adult neurogenic areas. Lentiviral transduction of active beta-catenin led to increased numbers of type B neural stem cells in the subventricular zone of adult brains, whereas deletion of Wnt7a or TLX resulted in decreased numbers of neural stem cells retaining bromodeoxyuridine label in the adult brain. Both Wnt7a and active beta-catenin significantly rescued a TLX (also known as Nr2e1) short interfering RNA-induced deficiency in neural stem cell proliferation. Lentiviral transduction of an active beta-catenin increased cell proliferation in neurogenic areas of TLX-null adult brains markedly. These results strongly support the hypothesis that TLX acts through the Wnt/beta-catenin pathway to regulate neural stem cell proliferation and self-renewal. Moreover, this study suggests that neural stem cells can promote their own self-renewal by secreting signalling molecules that act in an autocrine/paracrine mode.

  18. Zinc promotes proliferation and activation of myogenic cells via the PI3K/Akt and ERK signaling cascade

    Energy Technology Data Exchange (ETDEWEB)

    Ohashi, Kazuya, E-mail: asuno10k@yahoo.co.jp [Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo (Japan); Nagata, Yosuke, E-mail: cynagata@mail.ecc.u-tokyo.ac.jp [Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo (Japan); Wada, Eiji, E-mail: gacchu1@yahoo.co.jp [Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo (Japan); Zammit, Peter S., E-mail: peter.zammit@kcl.ac.uk [Randall Division of Cell and Molecular Biophysics, King' s College London, London SE1 1UL (United Kingdom); Shiozuka, Masataka, E-mail: cmuscle@mail.ecc.u-tokyo.ac.jp [Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo (Japan); Matsuda, Ryoichi, E-mail: cmatsuda@mail.ecc.u-tokyo.ac.jp [Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo (Japan)

    2015-05-01

    Skeletal muscle stem cells named muscle satellite cells are normally quiescent but are activated in response to various stimuli, such as injury and overload. Activated satellite cells enter the cell cycle and proliferate to produce a large number of myogenic progenitor cells, and these cells then differentiate and fuse to form myofibers. Zinc is one of the essential elements in the human body, and has multiple roles, including cell growth and DNA synthesis. However, the role of zinc in myogenic cells is not well understood, and is the focus of this study. We first examined the effects of zinc on differentiation of murine C2C12 myoblasts and found that zinc promoted proliferation, with an increased number of cells incorporating EdU, but inhibited differentiation with reduced myogenin expression and myotube formation. Furthermore, we used the C2C12 reserve cell model of myogenic quiescence to investigate the role of zinc on activation of myogenic cells. The number of reserve cells incorporating BrdU was increased by zinc in a dose dependent manner, with the number dramatically further increased using a combination of zinc and insulin. Akt and extracellular signal-regulated kinase (ERK) are downstream of insulin signaling, and both were phosphorylated after zinc treatment. The zinc/insulin combination-induced activation involved the phosphoinositide 3-kinase (PI3K)/Akt and ERK cascade. We conclude that zinc promotes activation and proliferation of myogenic cells, and this activation requires phosphorylation of PI3K/Akt and ERK as part of the signaling cascade. - Highlights: • Zinc has roles for promoting proliferation and inhibition differentiation of C2C12. • Zinc promotes activation of reserve cells. • Insulin and zinc synergize activation of reserve cells. • PI3K/Akt and ERK cascade affect zinc/insulin-mediated activation of reserve cells.

  19. Leishmania mexicana amazonensis: heterogeneity in 5-nucleotidase and peroxidase activities of mononuclear phagocytes during in vivo and in vitro infection Leishmania mexicana amazonensis: heterogeneidade da 5’-Nucleotidase e da peroxidase em fagócitos mononucleares durante infecção in vivo e in vitro

    Directory of Open Access Journals (Sweden)

    Suzana Côrte-Real

    1988-03-01

    Full Text Available The degree of maturation of cells of the Mononuclear Phagocyte System (MPS, during in vivo and in vitro infection by Leishmania mexicana amazonenesis, was evaluated in this study. The macrophages' differentiation was assayed by cytochemical characterization at the ultrastrctural level, using two well-established markers: 5'-nucleotidase enzyme activity, for revealing the mature cells, and the peroxidase activity present in the cell granules to demonstrate immature mononuclear phagocytes. only a few mcrophages, demonstrating 5'-nucleotidase positive reaction in both the plasma membrane and within their cytoplasmic vesicles, were found scattered in the chronic inflammation at the L. m. amazonensis lesions in albino mice. However, by the peroxidase activity analysis, we were also able to demonstrate the presence of immature MPS cells, which predominate, together with parasitized vacuolated macrophages, in chronic lesions induced in this systemby L. m. amazonensis. The implications of these results on the pathogenesis of murine cutaneous leishmaniasis are discussed.Um estudo sobre o grau de maturação das células do Sistema Fagocítico Mononuclear foi realizado durante a infecção in vivo e in vitro com a Leishmania mexicana amazonensis. A caracterização da diferenciação das células fagocíticas foi obtida com a localização ultraestrutural de dois marcadores enzimáticos bam conhecidos: a enzima 5'-Nucleotidase marcadora de membrana plasmática de células maduras e a enzima peroxidase, presente em grânulos, marcadora de células imaturas. A atividade da enzima 5'-Nucleotidase foi encontrada apenas em alguns macrófagos, presentes no foco inflamatório, em projeções da membrana plasmática e em algumas vesículas citoplasmáticas. Macrófagos peritoneais de camundongo apresentaram a mesma reatividade para este marcador. Contudo a análise da atividade peroxidásica demonstrou a predominância da presença de fagócitos mononucleares

  20. Peroxisome Proliferator-Activated Receptor-γ in Amyotrophic Lateral Sclerosis and Huntington’s Disease

    Directory of Open Access Journals (Sweden)

    Mahmoud Kiaei

    2008-01-01

    Full Text Available Amyotrophic lateral sclerosis (ALS is a debilitating and one of the most common adult-onset neurodegenerative diseases with the prevalence of about 5 per 100 000 individuals. It results in the progressive loss of upper and lower motor neurons and leads to gradual muscle weakening ultimately causing paralysis and death. ALS has an obscure cause and currently no effective treatment exists. In this review, a potentially important pathway is described that can be activated by peroxisome proliferator-activated receptor-γ (PPAR-γ agonists and has the ability to block the neuropathological damage caused by inflammation in ALS and possibly in other neudegenerative diseases like Huntington's disease (HD. Neuroinflammation is a common pathological feature in neurodegenerative diseases. Therefore, PPAR-γ agonists are thought to be neuroprotective in ALS and HD. We and others have tested the neuroprotective effect of pioglitazone (Actos, a PPAR-γ agonist, in G93A SOD1 transgenic mouse model of ALS and found significant increase in survival of G93A SOD1 mice. These findings suggest that PPAR-γ may be an important regulator of neuroinflammation and possibly a new target for the development of therapeutic strategies for ALS. The involvement of PPAR-γ in HD is currently under investigation, one study finds that the treatment with rosiglitazone had no protection in R6/2 transgenic mouse model of HD. PPAR-γ coactivator-1α (PGC-1α is a transcriptional coactivator that works together with combination of other transcription factors like PPAR-γ in the regulation of mitochondrial biogenesis. Therefore, PPAR-γ is a possible target for ALS and HD as it functions as transcription factor that interacts with PGC-1α. In this review, the role of PPAR-γ in ALS and HD is discussed based on the current literature and hypotheses.

  1. Dyospiros kaki phenolics inhibit colitis and colon cancer cell proliferation, but not gelatinase activities.

    Science.gov (United States)

    Direito, Rosa; Lima, Ana; Rocha, João; Ferreira, Ricardo Boavida; Mota, Joana; Rebelo, Patrícia; Fernandes, Adelaide; Pinto, Rui; Alves, Paula; Bronze, Rosário; Sepodes, Bruno; Figueira, Maria-Eduardo

    2017-08-01

    Polyphenols from persimmon (Diospyros kaki) have demonstrated radical-scavenging and antiinflammatory activities; however, little is known about the effects of persimmon phenolics on inflammatory bowel diseases (IBD) and colorectal cancer (CRC). Therefore, we aimed in this work to characterize the antiinflammatory and antiproliferative effects of a persimmon phenolic extract (80% acetone in water), using an in vivo model of experimental colitis and a model of cancer cell invasion. Our results show, for the first time, a beneficial effect of a persimmon phenolic extract in the attenuation of experimental colitis and a potential antiproliferative effect on cultured colon cancer cells. Administration of persimmon phenolic extract to mice with TNBS-induced colitis led to a reduction in several functional and histological markers of colon inflammation, namely: attenuation of colon length decrease, reduction of the extent of visible injury (ulcer formation), decrease in diarrhea severity, reduced mortality rate, reduction of mucosal hemorrhage and reduction of general histological features of colon inflammation. In vitro studies also showed that persimmon phenolic extract successfully impaired cell proliferation and invasion in HT-29 cells. Further investigation showed a decreased expression of COX-2 and iNOS in the colonic tissue of colitis mice, two important mediators of intestinal inflammation, but there was no inhibition of the gelatinase MMP-9 and MMP-2 activities. Given the role of inflammatory processes in the progression of CRC and the important link between inflammation and cancer, our results highlight the potential of persimmon polyphenols as a pharmacological tool in the treatment of patients with IBD. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. Saccharomyces boulardii inhibits lipopolysaccharide-induced activation of human dendritic cells and T cell proliferation

    Science.gov (United States)

    Thomas, S; Przesdzing, I; Metzke, D; Schmitz, J; Radbruch, A; Baumgart, D C

    2009-01-01

    Saccharomyces boulardii (Sb) is a probiotic yeast preparation that has demonstrated efficacy in inflammatory and infectious disorders of the gastrointestinal tract in controlled clinical trials. Although patients clearly benefit from treatment with Sb, little is known on how Sb unfolds its anti-inflammatory properties in humans. Dendritic cells (DC) balance tolerance and immunity and are involved critically in the control of T cell activation. Thus, they are believed to have a pivotal role in the initiation and perpetuation of chronic inflammatory disorders, not only in the gut. We therefore decided to investigate if Sb modulates DC function. Culture of primary (native, non-monocyte-derived) human myeloid CD1c+CD11c+CD123– DC (mDC) in the presence of Sb culture supernatant (active component molecular weight < 3 kDa, as evaluated by membrane partition chromatography) reduced significantly expression of the co-stimulatory molecules CD40 and CD80 (P < 0·01) and the DC mobilization marker CC-chemokine receptor CCR7 (CD197) (P < 0·001) induced by the prototypical microbial antigen lipopolysaccharide (LPS). Moreover, secretion of key proinflammatory cytokines such as tumour necrosis factor-α and interleukin (IL)-6 were notably reduced, while the secretion of anti-inflammatory IL-10 increased. Finally, Sb supernatant inhibited the proliferation of naive T cells in a mixed lymphocyte reaction with mDC. In summary, our data suggest that Sb may exhibit part of its anti-inflammatory potential through modulation of DC phenotype, function and migration by inhibition of their immune response to bacterial microbial surrogate antigens such as LPS. PMID:19161443

  3. Carbonic anhydrase III regulates peroxisome proliferator-activated receptor-{gamma}2

    Energy Technology Data Exchange (ETDEWEB)

    Mitterberger, Maria C. [Cell Metabolism and Differentiation Research Group, Institute for Biomedical Aging Research of the Austrian Academy of Sciences, 6020 Innsbruck (Austria); Kim, Geumsoo [Laboratory of Biochemistry, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892-8012 (United States); Rostek, Ursula [Cell Metabolism and Differentiation Research Group, Institute for Biomedical Aging Research of the Austrian Academy of Sciences, 6020 Innsbruck (Austria); Levine, Rodney L. [Laboratory of Biochemistry, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892-8012 (United States); Zwerschke, Werner, E-mail: werner.zwerschke@oeaw.ac.at [Cell Metabolism and Differentiation Research Group, Institute for Biomedical Aging Research of the Austrian Academy of Sciences, 6020 Innsbruck (Austria)

    2012-05-01

    Carbonic anhydrase III (CAIII) is an isoenzyme of the CA family. Because of its low specific anhydrase activity, physiological functions in addition to hydrating CO{sub 2} have been proposed. CAIII expression is highly induced in adipogenesis and CAIII is the most abundant protein in adipose tissues. The function of CAIII in both preadipocytes and adipocytes is however unknown. In the present study we demonstrate that adipogenesis is greatly increased in mouse embryonic fibroblasts (MEFs) from CAIII knockout (KO) mice, as demonstrated by a greater than 10-fold increase in the induction of fatty acid-binding protein-4 (FABP4) and increased triglyceride formation in CAIII{sup -/-} MEFs compared with CAIII{sup +/+} cells. To address the underlying mechanism, we investigated the expression of the two adipogenic key regulators, peroxisome proliferator-activated receptor-{gamma}2 (PPAR{gamma}2) and CCAAT/enhancer binding protein-{alpha}. We found a considerable (approximately 1000-fold) increase in the PPAR{gamma}2 expression in the CAIII{sup -/-} MEFs. Furthermore, RNAi-mediated knockdown of endogenous CAIII in NIH 3T3-L1 preadipocytes resulted in a significant increase in the induction of PPAR{gamma}2 and FABP4. When both CAIII and PPAR{gamma}2 were knocked down, FABP4 was not induced. We conclude that down-regulation of CAIII in preadipocytes enhances adipogenesis and that CAIII is a regulator of adipogenic differentiation which acts at the level of PPAR{gamma}2 gene expression. -- Highlights: Black-Right-Pointing-Pointer We discover a novel function of Carbonic anhydrase III (CAIII). Black-Right-Pointing-Pointer We show that CAIII is a regulator of adipogenesis. Black-Right-Pointing-Pointer We demonstrate that CAIII acts at the level of PPAR{gamma}2 gene expression. Black-Right-Pointing-Pointer Our data contribute to a better understanding of the role of CAIII in fat tissue.

  4. Abscisic Acid Regulates Inflammation via Ligand-binding Domain-independent Activation of Peroxisome Proliferator-activated Receptor γ*

    Science.gov (United States)

    Bassaganya-Riera, Josep; Guri, Amir J.; Lu, Pinyi; Climent, Montse; Carbo, Adria; Sobral, Bruno W.; Horne, William T.; Lewis, Stephanie N.; Bevan, David R.; Hontecillas, Raquel

    2011-01-01

    Abscisic acid (ABA) has shown efficacy in the treatment of diabetes and inflammation; however, its molecular targets and the mechanisms of action underlying its immunomodulatory effects remain unclear. This study investigates the role of peroxisome proliferator-activated receptor γ (PPAR γ) and lanthionine synthetase C-like 2 (LANCL2) as molecular targets for ABA. We demonstrate that ABA increases PPAR γ reporter activity in RAW 264.7 macrophages and increases ppar γ expression in vivo, although it does not bind to the ligand-binding domain of PPAR γ. LANCL2 knockdown studies provide evidence that ABA-mediated activation of macrophage PPAR γ is dependent on lancl2 expression. Consistent with the association of LANCL2 with G proteins, we provide evidence that ABA increases cAMP accumulation in immune cells. ABA suppresses LPS-induced prostaglandin E2 and MCP-1 production via a PPAR γ-dependent mechanism possibly involving activation of PPAR γ and suppression of NF-κB and nuclear factor of activated T cells. LPS challenge studies in PPAR γ-expressing and immune cell-specific PPAR γ null mice demonstrate that ABA down-regulates toll-like receptor 4 expression in macrophages and T cells in vivo through a PPAR γ-dependent mechanism. Global transcriptomic profiling and confirmatory quantitative RT-PCR suggest novel candidate targets and demonstrate that ABA treatment mitigates the effect of LPS on the expression of genes involved in inflammation, metabolism, and cell signaling, in part, through PPAR γ. In conclusion, ABA decreases LPS-mediated inflammation and regulates innate immune responses through a bifurcating pathway involving LANCL2 and an alternative, ligand-binding domain-independent mechanism of PPAR γ activation. PMID:21088297

  5. Abscisic acid regulates inflammation via ligand-binding domain-independent activation of peroxisome proliferator-activated receptor gamma.

    Science.gov (United States)

    Bassaganya-Riera, Josep; Guri, Amir J; Lu, Pinyi; Climent, Montse; Carbo, Adria; Sobral, Bruno W; Horne, William T; Lewis, Stephanie N; Bevan, David R; Hontecillas, Raquel

    2011-01-28

    Abscisic acid (ABA) has shown efficacy in the treatment of diabetes and inflammation; however, its molecular targets and the mechanisms of action underlying its immunomodulatory effects remain unclear. This study investigates the role of peroxisome proliferator-activated receptor γ (PPAR γ) and lanthionine synthetase C-like 2 (LANCL2) as molecular targets for ABA. We demonstrate that ABA increases PPAR γ reporter activity in RAW 264.7 macrophages and increases ppar γ expression in vivo, although it does not bind to the ligand-binding domain of PPAR γ. LANCL2 knockdown studies provide evidence that ABA-mediated activation of macrophage PPAR γ is dependent on lancl2 expression. Consistent with the association of LANCL2 with G proteins, we provide evidence that ABA increases cAMP accumulation in immune cells. ABA suppresses LPS-induced prostaglandin E(2) and MCP-1 production via a PPAR γ-dependent mechanism possibly involving activation of PPAR γ and suppression of NF-κB and nuclear factor of activated T cells. LPS challenge studies in PPAR γ-expressing and immune cell-specific PPAR γ null mice demonstrate that ABA down-regulates toll-like receptor 4 expression in macrophages and T cells in vivo through a PPAR γ-dependent mechanism. Global transcriptomic profiling and confirmatory quantitative RT-PCR suggest novel candidate targets and demonstrate that ABA treatment mitigates the effect of LPS on the expression of genes involved in inflammation, metabolism, and cell signaling, in part, through PPAR γ. In conclusion, ABA decreases LPS-mediated inflammation and regulates innate immune responses through a bifurcating pathway involving LANCL2 and an alternative, ligand-binding domain-independent mechanism of PPAR γ activation.

  6. Effect of peroxisome proliferator-activated receptor alpha activators on tumor necrosis factor expression in mice during endotoxemia.

    Science.gov (United States)

    Hill, M R; Clarke, S; Rodgers, K; Thornhill, B; Peters, J M; Gonzalez, F J; Gimble, J M

    1999-07-01

    Inflammatory mediators orchestrate the host immune and metabolic response to acute bacterial infections and mediate the events leading to septic shock. Tumor necrosis factor (TNF) has long been identified as one of the proximal mediators of endotoxin action. Recent studies have implicated peroxisome proliferator-activated receptor alpha (PPARalpha) as a potential target to modulate regulation of the immune response. Since PPARalpha activators, which are hypolipidemic drugs, are being prescribed for a significant population of older patients, it is important to determine the impact of these drugs on the host response to acute inflammation. Therefore, we examined the role of PPARalpha activators on the regulation of TNF expression in a mouse model of endotoxemia. CD-1 mice treated with dietary fenofibrate or Wy-14,643 had fivefold-higher lipopolysaccharide (LPS)-induced TNF plasma levels than LPS-treated control-fed animals. Higher LPS-induced TNF levels in drug-fed animals were reflected physiologically in significantly lower glucose levels in plasma and a significantly lower 50% lethal dose than those in LPS-treated control-fed animals. Utilizing PPARalpha wild-type (WT) and knockout (KO) mice, we showed that the effect of fenofibrate on LPS-induced TNF expression was indeed mediated by PPARalpha. PPARalpha WT mice fed fenofibrate also had a fivefold increase in LPS-induced TNF levels in plasma compared to control-fed animals. However, LPS-induced TNF levels were significantly decreased and glucose levels in plasma were significantly increased in PPARalpha KO mice fed fenofibrate compared to those in control-fed animals. Data from peritoneal macrophage studies indicate that Wy-14,643 modestly decreased TNF expression in vitro. Similarly, overexpression of PPARalpha in 293T cells decreased activity of a human TNF promoter-luciferase construct. The results from these studies suggest that any anti-inflammatory activity of PPARalpha in vivo can be masked by other

  7. Retinoid X receptor and peroxisome proliferator-activated receptor activate an estrogen responsive gene independent of the estrogen receptor.

    Science.gov (United States)

    Nuñez, S B; Medin, J A; Braissant, O; Kemp, L; Wahli, W; Ozato, K; Segars, J H

    1997-03-14

    Estrogen receptors regulate transcription of genes essential for sexual development and reproductive function. Since the retinoid X receptor (RXR) is able to modulate estrogen responsive genes and both 9-cis RA and fatty acids influenced development of estrogen responsive tumors, we hypothesized that estrogen responsive genes might be modulated by RXR and the fatty acid receptor (peroxisome proliferator-activated receptor, PPAR). To test this hypothesis, transfection assays in CV-1 cells were performed with an estrogen response element (ERE) coupled to a luciferase reporter construct. Addition of expression vectors for RXR and PPAR resulted in an 11-fold increase in luciferase activity in the presence of 9-cis RA. Furthermore, mobility shift assays demonstrated binding of RXR and PPAR to the vitellogenin A2-ERE and an ERE in the oxytocin promoter. Methylation interference assays demonstrated that specific guanine residues required for RXR/PPAR binding to the ERE were similar to residues required for ER binding. Moreover, RXR domain-deleted constructs in transfection assays showed that activation required RXR since an RXR delta AF-2 mutant completely abrogated reporter activity. Oligoprecipitation binding studies with biotinylated ERE and (35)S-labeled in vitro translated RXR constructs confirmed binding of delta AF-2 RXR mutant to the ERE in the presence of baculovirus-expressed PPAR. Finally, in situ hybridization confirmed RXR and PPAR mRNA expression in estrogen responsive tissues. Collectively, these data suggest that RXR and PPAR are present in reproductive tissues, are capable of activating estrogen responsive genes and suggest that the mechanism of activation may involve direct binding of the receptors to estrogen response elements.

  8. Structure-dependent binding and activation of perfluorinated compounds on human peroxisome proliferator-activated receptor γ

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Lianying [State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, 18 Shuangqing Road, Beijing 100085 (China); College of Life Science, Dezhou University, Dezhou 253023 (China); Ren, Xiao-Min; Wan, Bin [State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, 18 Shuangqing Road, Beijing 100085 (China); Guo, Liang-Hong, E-mail: LHGuo@rcees.ac.cn [State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, 18 Shuangqing Road, Beijing 100085 (China)

    2014-09-15

    Perfluorinated compounds (PFCs) have been shown to disrupt lipid metabolism and even induce cancer in rodents through activation of peroxisome proliferator-activated receptors (PPARs). Lines of evidence showed that PPARα was activated by PFCs. However, the information on the binding interactions between PPARγ and PFCs and subsequent alteration of PPARγ activity is still limited and sometimes inconsistent. In the present study, in vitro binding of 16 PFCs to human PPARγ ligand binding domain (hPPARγ-LBD) and their activity on the receptor in cells were investigated. The results showed that the binding affinity was strongly dependent on their carbon number and functional group. For the eleven perfluorinated carboxylic acids (PFCAs), the binding affinity increased with their carbon number from 4 to 11, and then decreased slightly. The binding affinity of the three perfluorinated sulfonic acids (PFSAs) was stronger than their PFCA counterparts. No binding was detected for the two fluorotelomer alcohols (FTOHs). Circular dichroim spectroscopy showed that PFC binding induced distinctive structural change of the receptor. In dual luciferase reporter assays using transiently transfected Hep G2 cells, PFCs acted as hPPARγ agonists, and their potency correlated with their binding affinity with hPPARγ-LBD. Molecular docking showed that PFCs with different chain length bind with the receptor in different geometry, which may contribute to their differences in binding affinity and transcriptional activity. - Highlights: • Binding affinity between PFCs and PPARγ was evaluated for the first time. • The binding strength was dependent on fluorinated carbon chain and functional group. • PFC binding induced distinctive structural change of the receptor. • PFCs could act as hPPARγ agonists in Hep G2 cells.

  9. The aryl hydrocarbon receptor suppresses osteoblast proliferation and differentiation through the activation of the ERK signaling pathway

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Haitao; Du, Yuxuan; Zhang, Xulong; Sun, Ying; Li, Shentao; Dou, Yunpeng [Department of Immunology, School of Basic Medical Sciences, Capital Medical University, No. 10 Xitoutiao, You An Men, Beijing 100069 (China); Li, Zhanguo [Department of Rheumatology and Immunology, Clinical Immunology Center, Peking University People' s Hospital, No. 11 Xizhimen South Street, Beijing 100044 (China); Yuan, Huihui, E-mail: huihui_yuan@163.com [Department of Immunology, School of Basic Medical Sciences, Capital Medical University, No. 10 Xitoutiao, You An Men, Beijing 100069 (China); Zhao, Wenming, E-mail: zhao-wenming@163.com [Department of Immunology, School of Basic Medical Sciences, Capital Medical University, No. 10 Xitoutiao, You An Men, Beijing 100069 (China)

    2014-11-01

    Ahr activation is known to be associated with synovitis and exacerbated rheumatoid arthritis (RA), but its contributions to bone loss have not been completely elucidated. Osteoblast proliferation and differentiation are abnormal at the erosion site in RA. Here, we reported that the expression of Ahr was increased in the hind paws' bone upon collagen-induced arthritis (CIA) in mice, and the levels of Ahr were negatively correlated with bone mineral density (BMD). In addition, immunofluorescent staining showed that the high expression of Ahr was mainly localized in osteoblasts from the CIA mice compared to normal controls. Moreover, the luciferase intensity of Ahr in the nucleus increased by 12.5% in CIA osteoblasts compared to that in normal controls. In addition, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) activation of the Ahr inhibited pre-osteoblast MC3T3-E1 cellular proliferation and differentiation in a dose-dependent manner. Interestingly, the levels of alkaline phosphatase (ALP) mRNA expression in the osteoblasts of CIA mice were reduced compared to normal controls. In contrast, decreased ALP expression by activated Ahr was completely reversed after pretreatment with an Ahr inhibitor (CH-223191) in MC3T3-E1 cell lines and primary osteoblasts on day 5. Our data further showed that activation of Ahr promoted the phosphorylation of ERK after 5 days. Moreover, Ahr-dependent activation of the ERK signaling pathway decreased the levels of proliferation cells and inhibited ALP activity in MC3T3-E1 cells. These results demonstrated that the high expression of Ahr may suppress osteoblast proliferation and differentiation through activation of the ERK signaling pathway, further enabling bone erosion in CIA mice. - Highlights: • The upregulation of Ahr was localized in osteoblasts of CIA mice. • The overexpression of Ahr suppressed osteoblast development. • The Ahr activated ERK signaling pathway to exacerbate bone erosion.

  10. Melatonin regulates CRE-dependent gene transcription underlying osteoblast proliferation by activating Src and PKA in parallel.

    Science.gov (United States)

    Tao, Lin; Zhu, Yue

    2018-01-01

    Several studies have indicated a relationship between melatonin and idiopathic scoliosis, including our previous work which demonstrated that melatonin can inhibit osteoblast proliferation; however, the mechanism remains unclear. Here, we utilized a MTT assay to show that melatonin significantly reduces osteoblast proliferation in a concentration-and time-dependent manner. Through a combination of techniques, including real-time PCR, MTT assays, immunofluorescence, and luciferase assays, we confirmed that melatonin-induced changes in phosphorylated cAMP response element-binding protein (CREB) reduced transcriptional activity in a melatonin receptor-dependent manner. Surprisingly, treatment of osteoblasts with the mitogen-activated protein kinase/extracellular signal-regulated kinase kinase (MEK) inhibitor PD98059 up-regulated other cascades upstream of CREB. We next treated cells with PKA and Src inhibitors and observed that melatonin can also activate the protein kinase A (PKA) and Src pathways. To examine whether Src is upstream from the cAMP-PKA pathway, we measured cAMP levels in response to melatonin with and without a Src inhibitor (PP2) and found that PP2 had no additional effect. Therefore, the transcription-dependent mechanisms involved in CREB phosphorylation, along with melatonin, activated Src via a parallel signaling pathway that was separate from that of PKA. Finally, we transfected osteoblasts with lentiviral CREB short hairpin (sh) RNAs and found a decrease in the expression of proliferating cell nuclear antigen (PCNA) and osteoblast proliferation. These results suggest that CREB and PCNA are downstream targets of melatonin signaling, and that the down-regulation of CREB, which is regulated via PKA and Src pathways, contributes to the melatonin-induced inhibition of osteoblast proliferation.

  11. Fisetin inhibits the proliferation of gastric cancer cells and induces apoptosis through suppression of ERK 1/2 activation.

    Science.gov (United States)

    Yan, Weixin; Chen, Shouhui; Zhao, Yiyang; Ye, Xiaoyu

    2018-06-01

    The present study aimed to investigate the effect of fisetin on proliferation and apoptosis of gastric cancer cells, as well as the underlying mechanism. Proliferation in SGC7901 cancer and GES-1 normal cells was analyzed using a CCK-8 assay. Apoptosis was analyzed using an Annexin V/Propidium Iodide apoptosis kit and phosphorylation of extracellular signal-regulated kinase (ERK) 1/2 was analyzed by western blot assay. Treatment of SGC7901 cells with various concentrations (1, 5, 10, 15 and 20 µM) of fisetin for 48 h resulted in a concentration dependent reduction in proliferation. Flow cytometry revealed a marked increase in apoptosis from 5 µM concentration of fisetin after 48 h. The percentage of apoptotic cells increased to 87% following treatment with 15 µM fisetin for 48 h, compared with 2% in control. Treatment of SGC7901 cells with fisetin for 48 h resulted in a reduction in the activation of ERK 1/2 in a concentration-dependent manner. The reduction in activation of ERK 1/2 was significant following treatment with 15 µM fisetin for 48 h. The inhibitory effect of fisetin on activation of ERK 1/2 was further demonstrated using the ERK 1/2 inhibitor, PD98059. The results indicated a significant reduction in the proliferation of SGC7901 cells following treatment with PD98059 (P<0.002). The reduction by PD98059 administration was comparable to that observed following fisetin treatment for 48 h. In conclusion, the current study demonstrates that fisetin inhibits the proliferation of gastric cancer cells and induces apoptosis through suppression of ERK 1/2 activation. Thus, fisetin may have therapeutic applications in the treatment of gastric cancer.

  12. Platelet-rich plasma stimulated by pulse electric fields: Platelet activation, procoagulant markers, growth factor release and cell proliferation.

    Science.gov (United States)

    Frelinger, A L; Torres, A S; Caiafa, A; Morton, C A; Berny-Lang, M A; Gerrits, A J; Carmichael, S L; Neculaes, V B; Michelson, A D

    2016-01-01

    Therapeutic use of activated platelet-rich plasma (PRP) has been explored for wound healing, hemostasis and antimicrobial wound applications. Pulse electric field (PEF) stimulation may provide more consistent platelet activation and avoid complications associated with the addition of bovine thrombin, the current state of the art ex vivo activator of therapeutic PRP. The aim of this study was to compare the ability of PEF, bovine thrombin and thrombin receptor activating peptide (TRAP) to activate human PRP, release growth factors and induce cell proliferation in vitro. Human PRP was prepared in the Harvest SmartPreP2 System and treated with vehicle, PEF, bovine thrombin, TRAP or Triton X-100. Platelet activation and procoagulant markers and microparticle generation were measured by flow cytometry. Released growth factors were measured by ELISA. The releasates were tested for their ability to stimulate proliferation of human epithelial cells in culture. PEF produced more platelet-derived microparticles, P-selectin-positive particles and procoagulant annexin V-positive particles than bovine thrombin or TRAP. These differences were associated with higher levels of released epidermal growth factor after PEF than after bovine thrombin or TRAP but similar levels of platelet-derived, vascular-endothelial, and basic fibroblast growth factors, and platelet factor 4. Supernatant from PEF-treated platelets significantly increased cell proliferation compared to plasma. In conclusion, PEF treatment of fresh PRP results in generation of microparticles, exposure of prothrombotic platelet surfaces, differential release of growth factors compared to bovine thrombin and TRAP and significant cell proliferation. These results, together with PEF's inherent advantages, suggest that PEF may be a superior alternative to bovine thrombin activation of PRP for therapeutic applications.

  13. The identification of CD163 expressing phagocytic chondrocytes in joint cartilage and its novel scavenger role in cartilage degradation.

    Directory of Open Access Journals (Sweden)

    Kai Jiao

    Full Text Available BACKGROUND: Cartilage degradation is a typical characteristic of arthritis. This study examined whether there was a subset of phagocytic chondrocytes that expressed the specific macrophage marker, CD163, and investigated their role in cartilage degradation. METHODS: Cartilage from the knee and temporomandibular joints of Sprague-Dawley rats was harvested. Cartilage degradation was experimentally-induced in rat temporomandibular joints, using published biomechanical dental methods. The expression levels of CD163 and inflammatory factors within cartilage, and the ability of CD163(+ chondrocytes to conduct phagocytosis were investigated. Cartilage from the knees of patients with osteoarthritis and normal cartilage from knee amputations was also investigated. RESULTS: In the experimentally-induced degrading cartilage from temporomandibular joints, phagocytes were capable of engulfing neighboring apoptotic and necrotic cells, and the levels of CD163, TNF-α and MMPs were all increased (P0.05. CD163(+ chondrocytes were found in the cartilage mid-zone of temporomandibular joints and knee from healthy, three-week old rats. Furthermore, an increased number of CD163(+ chondrocytes with enhanced phagocytic activity were present in Col-II(+ chondrocytes isolated from the degraded cartilage of temporomandibular joints in the eight-week experimental group compared with their age-matched controls. Increased number with enhanced phagocytic activity of CD163(+ chondrocytes were also found in isolated Col-II(+ chondrocytes stimulated with TNF-α (P<0.05. Mid-zone distribution of CD163(+ cells accompanied with increased expression of CD163 and TNF-α were further confirmed in the isolated Col-II(+ chondrocytes from the knee cartilage of human patients with osteoarthritis, in contrast to the controls (both P<0.05. CONCLUSIONS: An increased number of CD163(+ chondrocytes with enhanced phagocytic activity were discovered within degraded joint cartilage, indicating a

  14. Lipid-binding proteins modulate ligand-dependent trans-activation by peroxisome proliferator-activated receptors and localize to the nucleus as well as the cytoplasm

    DEFF Research Database (Denmark)

    Helledie, T; Antonius, M; Sorensen, R V

    2000-01-01

    Peroxisome proliferator-activated receptors (PPARs) are activated by a variety of fatty acids, eicosanoids, and hypolipidemic and insulin-sensitizing drugs. Many of these compounds bind avidly to members of a family of small lipid-binding proteins, the fatty acid-binding proteins (FABPs). Fatty...

  15. Medium chain fatty acids are selective peroxisome proliferator activated receptor (PPAR γ activators and pan-PPAR partial agonists.

    Directory of Open Access Journals (Sweden)

    Marcelo Vizoná Liberato

    Full Text Available Thiazolidinediones (TZDs act through peroxisome proliferator activated receptor (PPAR γ to increase insulin sensitivity in type 2 diabetes (T2DM, but deleterious effects of these ligands mean that selective modulators with improved clinical profiles are needed. We obtained a crystal structure of PPARγ ligand binding domain (LBD and found that the ligand binding pocket (LBP is occupied by bacterial medium chain fatty acids (MCFAs. We verified that MCFAs (C8-C10 bind the PPARγ LBD in vitro and showed that they are low-potency partial agonists that display assay-specific actions relative to TZDs; they act as very weak partial agonists in transfections with PPARγ LBD, stronger partial agonists with full length PPARγ and exhibit full blockade of PPARγ phosphorylation by cyclin-dependent kinase 5 (cdk5, linked to reversal of adipose tissue insulin resistance. MCFAs that bind PPARγ also antagonize TZD-dependent adipogenesis in vitro. X-ray structure B-factor analysis and molecular dynamics (MD simulations suggest that MCFAs weakly stabilize C-terminal activation helix (H 12 relative to TZDs and this effect is highly dependent on chain length. By contrast, MCFAs preferentially stabilize the H2-H3/β-sheet region and the helix (H 11-H12 loop relative to TZDs and we propose that MCFA assay-specific actions are linked to their unique binding mode and suggest that it may be possible to identify selective PPARγ modulators with useful clinical profiles among natural products.

  16. Impairments in cognition and neural precursor cell proliferation in mice expressing constitutively active glycogen synthase kinase-3

    Directory of Open Access Journals (Sweden)

    Marta ePardo

    2015-03-01

    Full Text Available ABSTRACTBrain glycogen synthase kinase-3 (GSK3 is hyperactive in several neurological conditions that involve impairments in both cognition and neurogenesis. This raises the hypotheses that hyperactive GSK3 may directly contribute to impaired cognition, and that this may be related to deficiencies in neural precursor cells (NPC. To study the effects of hyperactive GSK3 in the absence of disease influences, we compared adult hippocampal NPC proliferation and performance in three cognitive tasks in male and female wild-type mice and GSK3 knockin mice, which express constitutively active GSK3. NPC proliferation was ~40% deficient in both male and female GSK3 knockin mice compared with wild-type mice. Environmental enrichment (EE increased NPC proliferation in male, but not female, GSK3 knockin mice and wild-type mice. Male and female GSK3 knockin mice exhibited impairments in novel object recognition, temporal order memory, and coordinate spatial processing compared with gender-matched wild-type mice. EE restored impaired novel object recognition and temporal ordering in both sexes of GSK3 knockin mice, indicating that this repair was not dependent on NPC proliferation, which was not increased by EE in female GSK3 knockin mice. Acute 1 hr pretreatment with the GSK3 inhibitor TDZD-8 also improved novel object recognition and temporal ordering in male and female GSK3 knockin mice. These findings demonstrate that hyperactive GSK3 is sufficient to impair adult hippocampal NPC proliferation and to impair performance in three cognitive tasks in both male and female mice, but these changes in NPC proliferation do not directly regulate novel object recognition and temporal ordering tasks.

  17. The threonine protease activity of testes-specific protease 50 (TSP50 is essential for its function in cell proliferation.

    Directory of Open Access Journals (Sweden)

    Yu-Yin Li

    Full Text Available BACKGROUND: Testes-specific protease 50 (TSP50, a newly discovered threonine enzyme, has similar amino acid sequences and enzymatic structures to those of many serine proteases. It may be an oncogene. TSP50 is up-regulated in breast cancer epithelial cells, and ectopic expression of TSP50 in TSP50-deficient Chinese hamster ovary (CHO cells has been found to promote cell proliferation. However, the mechanisms by which TSP50 exerts its growth-promoting effects are not yet fully understood. METHODOLOGY/PRINCIPAL FINDINGS: To delineate whether the threonine protease activity of TSP50 is essential to its function in cell proliferation, we constructed and characterized a mutant TSP50, called TSP50 T310A, which was identified as a protease-dead mutant of TSP50. By a series of proliferation analyses, colony formation assays and apoptosis analyses, we showed that T310A mutation significantly depresses TSP50-induced cell proliferation in vitro. Next, the CHO stable cell line expressing either wild-type or T310A mutant TSP50 was injected subcutaneously into nude mice. We found that the T310A mutation could abolish the tumorigenicity of TSP50 in vivo. A mechanism investigation revealed that the T310A mutation prevented interaction between TSP50 and the NF-κBIκBα complex, which is necessary for TSP50 to perform its function in cell proliferation. CONCLUSION: Our data highlight the importance of threonine 310, the most critical protease catalytic site in TSP50, to TSP50-induced cell proliferation and tumor formation.

  18. Activation of peroxisome proliferator-activated receptor-α (PPARα) suppresses postprandial lipidemia through fatty acid oxidation in enterocytes

    International Nuclear Information System (INIS)

    Kimura, Rino; Takahashi, Nobuyuki; Murota, Kaeko; Yamada, Yuko; Niiya, Saori; Kanzaki, Noriyuki; Murakami, Yoko; Moriyama, Tatsuya; Goto, Tsuyoshi; Kawada, Teruo

    2011-01-01

    Highlights: → PPARα activation increased mRNA expression levels of fatty acid oxidation-related genes in human intestinal epithelial Caco-2 cells. → PPARα activation also increased oxygen consumption rate and CO 2 production and decreased secretion of triglyceride and ApoB from Caco-2 cells. → Orally administration of bezafibrate increased mRNA expression levels of fatty acid oxidation-related genes and CO 2 production in small intestinal epithelial cells. → Treatment with bezafibrate decreased postprandial serum concentration of triglyceride after oral injection of olive oil in mice. → It suggested that intestinal lipid metabolism regulated by PPARα activation suppresses postprandial lipidemia. -- Abstract: Activation of peroxisome proliferator-activated receptor (PPAR)-α which regulates lipid metabolism in peripheral tissues such as the liver and skeletal muscle, decreases circulating lipid levels, thus improving hyperlipidemia under fasting conditions. Recently, postprandial serum lipid levels have been found to correlate more closely to cardiovascular diseases than fasting levels, although fasting hyperlipidemia is considered an important risk of cardiovascular diseases. However, the effect of PPARα activation on postprandial lipidemia has not been clarified. In this study, we examined the effects of PPARα activation in enterocytes on lipid secretion and postprandial lipidemia. In Caco-2 enterocytes, bezafibrate, a potent PPARα agonist, increased mRNA expression levels of fatty acid oxidation-related genes, such as acyl-CoA oxidase, carnitine palmitoyl transferase, and acyl-CoA synthase, and oxygen consumption rate (OCR) and suppressed secretion levels of both triglycerides and apolipoprotein B into the basolateral side. In vivo experiments revealed that feeding high-fat-diet containing bezafibrate increased mRNA expression levels of fatty acid oxidation-related genes and production of CO 2 and acid soluble metabolites in enterocytes. Moreover

  19. Peroxisome Proliferator-Activated Receptor Gamma Polymorphisms and Coronary Heart Disease

    Directory of Open Access Journals (Sweden)

    Jean Dallongeville

    2009-01-01

    Full Text Available Single nucleotide polymorphisms (SNPs in the peroxisome proliferator-activated receptor γ (PPARG gene have been associated with cardiovascular risk factors, particularly obesity and diabetes. We assessed the relationship between 4 PPARG SNPs (C-681G, C-689T, Pro12Ala, and C1431T and coronary heart disease (CHD in the PRIME (249 cases/494 controls, only men and ADVANCE (1,076 cases/805 controls, men or women studies. In PRIME, homozygote individuals for the minor allele of the PPARG C-689T, Pro12Ala, and C1431T SNPs tended to have a higher risk of CHD than homozygote individuals for the frequent allele (adjusted OR [95% CI] = 3.43 [0.96–12.27], P=.058, 3.41 [0.95–12.22], P=.060 and 5.10 [0.99–26.37], P=.050, resp.. No such association could be detected in ADVANCE. Haplotype distributions were similar in cases and control in both studies. A meta-analysis on the Pro12Ala SNP, based on our data and 11 other published association studies (6,898 CHD cases/11,287 controls, revealed that there was no evidence for a significant association under the dominant model (OR=0.99 [0.92–1.07], P=.82. However, there was a borderline association under the recessive model (OR=1.29 [0.99–1.67], P=.06 that became significant when considering men only (OR=1.73 [1.20–2.48], P=.003. In conclusion, the PPARG Ala12Ala genotype might be associated with a higher CHD risk in men but further confirmation studies are needed.

  20. K-ras2 Activation and Genome Instability Increase Proliferation and Size of FAP Adenomas

    Directory of Open Access Journals (Sweden)

    Anna Rapallo

    1999-01-01

    Full Text Available The possible role of K‐ras2 mutations and aneuploidy toward increase of proliferation and adenoma size in Familial Adenomatous Polyposis (FAP adenomas is not known. The present study addresses these issues by investigating 147 colorectal adenomas obtained from four FAP patients. The majority of adenomas had size lower than or equal to 10 mm (86%, low grade dysplasia (63%, and were preferentially located in the right colon (60%. Normal mucosa samples were obtained from 19 healthy donors. Three synchronous adenocarcinomas were also investigated. K‐ras2 mutation spectrum was analysed by PCR and Sequence Specific Oligonucleotide (SSO hybridization, while flow cytometry (FCM was used for evaluating degree of DNA ploidy and S‐phase fraction. Overall, incidences of K‐ras2 mutations, DNA aneuploidy and high S‐phase values (>7.2% were 6.6%, 5.4% and 10.5%, respectively. In particular, among the adenomas with size lower than 5 mm, K‐ras2 mutation and DNA aneuploidy frequencies were only slightly above 1%. Statistically significant correlations were found between K‐ras2 and size, DNA ploidy and size and K‐ras2 and S‐phase (p. In particular, among the wild type K‐ras2 adenomas, high S‐phase values were detected in 8% of the cases versus 57% among the K‐ras2 mutated adenomas (p=0.0005. The present series of FAP adenomas indicates that K‐ras2 activation and gross genomic changes play a role toward a proliferative gain and tumour growth in size.

  1. Elafibranor, an Agonist of the Peroxisome Proliferator-Activated Receptor-alpha and -delta, Induces Resolution of Nonalcoholic Steatohepatitis Without Fibrosis Worsening

    NARCIS (Netherlands)

    Ratziu, V.; Harrison, S.A.; Francque, S.; Bedossa, P.; Lehert, P.; Serfaty, L.; Romero-Gomez, M.; Boursier, J.; Abdelmalek, M.; Caldwell, S.; Drenth, J.P.; Anstee, Q.M.; Hum, D.; Hanf, R.; Roudot, A.; Megnien, S.; Staels, B.; Sanyal, A.

    2016-01-01

    BACKGROUND & AIMS: Elafibranor is an agonist of the peroxisome proliferator-activated receptor-alpha and peroxisome proliferator-activated receptor-delta. Elafibranor improves insulin sensitivity, glucose homeostasis, and lipid metabolism and reduces inflammation. We assessed the safety and efficacy

  2. Central fuel banking to reduce the number of proliferation sensitive enrichment activities

    International Nuclear Information System (INIS)

    Cserhati, A.

    2008-01-01

    Central fuel banking is a complex international political, economic and technical concept that aims to reduce uncontrolled spreading of uranium enrichment technology in the world in order to prevent proliferation of nuclear weapons. This paper first gives an outline of the notions: 'non-proliferation', the 'front-end' of the fuel cycle, the scope of fuel baking, nuclear fuel and the 60 years of enrichment technology. Enrichment technology is highly concentrated in the nuclear weapon states and other developed countries, but this is not exclusive any more. The technology is spreading. The global demand for enrichment services - parallel to massive nuclear investments in the civil sector and the ageing of older facilities - is constantly growing. Proliferation sensitivity calls for an effective and comprehensive non-proliferation regime. The solution may be multilateralizing the nuclear fuel cycle. After a historical overview, the proposals on multilateral nuclear approaches are presented. The assessment of the proposals is complex in the dimensions of: the non-proliferation aim, the assurance of supply aspect and other variables such as legal issues and non-nuclear inducements. A general evaluation and the recommendations of the Expert Panel of the IAEA are introduced outlining a plan on a middle- and long-term basis. The conclusion of the paper stresses the importance and challenge in finding the 'new balance' between obligations and interests of the members of the global community stating that the answers will have a significant impact on the nuclear indus- try, world wide economics and security policy. (orig.)

  3. Cytotoxic activities of amentoflavone against human breast and cervical cancers are mediated by increasing of PTEN expression levels due to peroxisomes proliferate-activated receptor {gamma} activation

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Eunjung; Shin, Soyoung; Lee, Jeeyoung; Lee, So Jung; Kim, Jinkyoung; Yoon, Doyoung; Kim, Yangmee [Konkuk Univ., Seoul (Korea, Republic of); Woo, Eunrhan [Chosun Univ., Gwangju (Korea, Republic of)

    2012-07-15

    Human peroxisomes proliferate-activated receptor gamma (hPPAR{gamma}) has been implicated in numerous pathologies, including obesity, diabetes, and cancer. Previously, we verified that amentoflavone is an activator of hPPAR{gamma} and probed the molecular basis of its action. In this study, we investigated the mechanism of action of amentoflavone in cancer cells and demonstrated that amentoflavone showed strong cytotoxicity against MCF-7 and HeLa cancer cell lines. We showed that hPPAR{gamma} expression in MCF-7 and HeLa cells is specifically stimulated by amentoflavone, and suggested that amentoflavone-induced cytotoxic activities are mediated by activation of hPPAR{gamma} in these two cancer cell lines. Moreover, amentoflavone increased PTEN levels in these two cancer cell lines, indicating that the cytotoxic activities of amentoflavone are mediated by increasing of PTEN expression levels due to hPPAR{gamma} activation.

  4. Malignant T cells exhibit CD45 resistant Stat 3 activation and proliferation in cutaneous T cell lymphoma

    DEFF Research Database (Denmark)

    Krejsgaard, T; Helvad, Rikke; Ralfkiær, Elisabeth

    2010-01-01

    CD45 is a protein tyrosine phosphatase, which is well-known for regulating antigen receptor signalling in T and B cells via its effect on Src kinases. It has recently been shown that CD45 can also dephosphorylate Janus kinases (Jaks) and thereby regulate Signal transducer and activator of transcr......CD45 is a protein tyrosine phosphatase, which is well-known for regulating antigen receptor signalling in T and B cells via its effect on Src kinases. It has recently been shown that CD45 can also dephosphorylate Janus kinases (Jaks) and thereby regulate Signal transducer and activator...... of transcription (Stat) activation and cytokine-induced proliferation in lymphocytes. Consequently, CD45 dysregulation could be implicated in aberrant Jak/Stat activation and proliferation in lymphoproliferative diseases. Despite high expression of the CD45 ligand, Galectin-1, in skin lesions from cutaneous T......-cell lymphoma (CTCL), the malignant T cells exhibit constitutive activation of the Jak3/Stat3 signalling pathway and uncontrolled proliferation. We show that CD45 expression is down-regulated on malignant T cells when compared to non-malignant T cells established from CTCL skin lesions. Moreover, CD45 cross...

  5. Aspirin-induced AMP-activated protein kinase activation regulates the proliferation of vascular smooth muscle cells from spontaneously hypertensive rats

    International Nuclear Information System (INIS)

    Sung, Jin Young; Choi, Hyoung Chul

    2011-01-01

    Highlights: → Aspirin-induced AMPK phosphorylation was greater in VSMC from SHR than WKY. → Aspirin-induced AMPK phosphorylation inhibited proliferation of VSMC from SHR. → Low basal AMPK phosphorylation in SHR elicits increased VSMC proliferation. → Inhibition of AMPK restored decreased VSMC proliferation by aspirin in SHR. → Aspirin exerts anti-proliferative effect through AMPK activation in VSMC from SHR. -- Abstract: Acetylsalicylic acid (aspirin), used to reduce risk of cardiovascular disease, plays an important role in the regulation of cellular proliferation. However, mechanisms responsible for aspirin-induced growth inhibition are not fully understood. Here, we investigated whether aspirin may exert therapeutic effects via AMP-activated protein kinase (AMPK) activation in vascular smooth muscle cells (VSMC) from wistar kyoto rats (WKY) and spontaneously hypertensive rats (SHR). Aspirin increased AMPK and acetyl-CoA carboxylase phosphorylation in a time- and dose-dependent manner in VSMCs from WKY and SHR, but with greater efficacy in SHR. In SHR, a low basal phosphorylation status of AMPK resulted in increased VSMC proliferation and aspirin-induced AMPK phosphorylation inhibited proliferation of VSMCs. Compound C, an AMPK inhibitor, and AMPK siRNA reduced the aspirin-mediated inhibition of VSMC proliferation, this effect was more pronounced in SHR than in WKY. In VSMCs from SHR, aspirin increased p53 and p21 expression and inhibited the expression of cell cycle associated proteins, such as p-Rb, cyclin D, and cyclin E. These results indicate that in SHR VSMCs aspirin exerts anti-proliferative effects through the induction of AMPK phosphorylation.

  6. Aspirin-induced AMP-activated protein kinase activation regulates the proliferation of vascular smooth muscle cells from spontaneously hypertensive rats

    Energy Technology Data Exchange (ETDEWEB)

    Sung, Jin Young [Department of Pharmacology, College of Medicine, Yeungnam University, Daegu 705-717 (Korea, Republic of); Choi, Hyoung Chul, E-mail: hcchoi@med.yu.ac.kr [Department of Pharmacology, College of Medicine, Yeungnam University, Daegu 705-717 (Korea, Republic of)

    2011-05-06

    Highlights: {yields} Aspirin-induced AMPK phosphorylation was greater in VSMC from SHR than WKY. {yields} Aspirin-induced AMPK phosphorylation inhibited proliferation of VSMC from SHR. {yields} Low basal AMPK phosphorylation in SHR elicits increased VSMC proliferation. {yields} Inhibition of AMPK restored decreased VSMC proliferation by aspirin in SHR. {yields} Aspirin exerts anti-proliferative effect through AMPK activation in VSMC from SHR. -- Abstract: Acetylsalicylic acid (aspirin), used to reduce risk of cardiovascular disease, plays an important role in the regulation of cellular proliferation. However, mechanisms responsible for aspirin-induced growth inhibition are not fully understood. Here, we investigated whether aspirin may exert therapeutic effects via AMP-activated protein kinase (AMPK) activation in vascular smooth muscle cells (VSMC) from wistar kyoto rats (WKY) and spontaneously hypertensive rats (SHR). Aspirin increased AMPK and acetyl-CoA carboxylase phosphorylation in a time- and dose-dependent manner in VSMCs from WKY and SHR, but with greater efficacy in SHR. In SHR, a low basal phosphorylation status of AMPK resulted in increased VSMC proliferation and aspirin-induced AMPK phosphorylation inhibited proliferation of VSMCs. Compound C, an AMPK inhibitor, and AMPK siRNA reduced the aspirin-mediated inhibition of VSMC proliferation, this effect was more pronounced in SHR than in WKY. In VSMCs from SHR, aspirin increased p53 and p21 expression and inhibited the expression of cell cycle associated proteins, such as p-Rb, cyclin D, and cyclin E. These results indicate that in SHR VSMCs aspirin exerts anti-proliferative effects through the induction of AMPK phosphorylation.

  7. Enhancement in ex vivo phagocytic capacity of peritoneal leukocytes in mice by oral delivery of various lactic-acid-producing bacteria.

    Science.gov (United States)

    Lee, Yeonhee; Lee, Taik-Soo

    2005-01-01

    Lactic-acid-producing bacteria (LABs) are known to have immunomodulating activity. In the current study, various LABs were tested for their immunity-enhancing activity, especially the phagocytic activity of leukocytes. Viable but not heat-killed cells of Weissella kimchii strain PL9001, Lactobacillus fermentum strain PL9005, and L. plantarum strain PL9011 significantly increased the ex vivo phagocytic capacity of mouse peritoneal leukocytes to ingest fluorescein isothiocyanate (FITC)-labeled Escherichia coli in a strain-dependent manner. Results of this and previous studies suggest these LABs as candidates for new probiotics. This is the first report of the enhancement of peritoneal leukocyte activity of these species.

  8. Designed modulation of sex steroid signaling inhibits telomerase activity and proliferation of human prostate cancer cells

    International Nuclear Information System (INIS)

    Verma, Vikas; Sharma, Vikas; Singh, Vishal; Sharma, Siddharth; Bishnoi, Ajay Kumar; Chandra, Vishal; Maikhuri, J.P.; Dwivedi, Anila; Kumar, Atul; Gupta, Gopal

    2014-01-01

    The predominant estrogen-receptor (ER)-β signaling in normal prostate is countered by increased ER-α signaling in prostate cancer (CaP), which in association with androgen-receptor (AR) signaling results in pathogenesis of the disease. However CaP treatments mostly target AR signaling which is initially effective but eventually leads to androgen resistance, hence simultaneous targeting of ERs has been proposed. A novel series of molecules were designed with multiple sex-steroid receptor modulating capabilities by coalescing the pharmacophores of known anti-CaP molecules that act via modulation of ER(α/β) and/or AR, viz. 3,3′diindolylmethane (DIM), mifepristone, toremifene, tamoxifen and raloxifene. N,N-diethyl-4-((2-(4-methoxyphenyl)-1H-indol-3-yl)methyl) aniline (DIMA) was identified as the most promising structure of this new series. DIMA increased annexin-V labelling, cell-cycle arrest and caspase-3 activity, and decreased expression of AR and prostate specific antigen in LNCaP cells, in vitro. Concurrently, DIMA increased ER-β, p21 and p27 protein levels in LNCaP cells and exhibited ∼ 5 times more selective binding for ER-β than ER-α, in comparison to raloxifene. DIMA exhibited a dose-dependent ER-β agonism and ER-α antagonism in classical gene reporter assay and decreased hTERT (catalytic subunit of telomerase) transcript levels in LNCaP at 3.0 μM (P < 0.05). DIMA also dose-dependently decreased telomerase enzyme activity in prostate cancer cells. It is thus concluded that DIMA acts as a multi-steroid receptor modulator and effectively inhibits proliferation of prostate cancer cells through ER-β mediated telomerase inhibition, by countering actions of ER-α and AR. Its unique molecular design can serve as a lead structure for generation of potent agents against endocrine malignancies like the CaP

  9. Dysregulation of gene expression within the peroxisome proliferator activated receptor pathway in morbidly obese patients.

    Science.gov (United States)

    Hindle, A Katharine; Koury, Jadd; McCaffrey, Tim; Fu, Sidney W; Brody, Fred

    2009-06-01

    The causes of obesity are multifactorial but may include dysregulation of a family of related genes, such as the peroxisome proliferator activated receptor gamma (PPARgamma). When activated, the PPARgamma pathway promotes lipid metabolism. This study used microarray technology to evaluate differential gene expression profiles in obese patients undergoing bariatric surgery. The study enrolled six morbidly obese patients with a body mass index (BMI) exceeding 35 and four nonobese individuals. Blood samples were stabilized in PaxGene tubes (PreAnalytiX), and total RNA was extracted. Next, 100 ng of total RNA was amplified and labeled using the Ovation RNA Amplification System V2 with the Ovation whole-blood reagent (NuGen) before it was hybridized to an Affymetrix (Santa Clara, CA) focus array containing more than 8,500 verified genes. The data were analyzed using an analysis of variance (ANOVA) (p < 0.05) in the GeneSpring program, and potential pathways were identified with the Ingenuity program. Real-time quantitative reverse transcriptase-polymerase chain reaction was used to validate the array data. A total of 97 upregulated genes and 125 downregulated genes were identified. More than a 1.5-fold change was identified between the morbidly obese patients and the control subjects for a cluster of dysregulated genes involving pathways regulating cell metabolism and lipid formation. Specifically, the PPARgamma pathway showed a plethora of dysregulated genes including tumor necrosis factor-alpha (TNFalpha). In morbidly obese patients, TNFalpha expression was increased (upregulated) 1.6-fold. These findings were confirmed using quantitative polymerase chain reaction with a 2.8-fold change. Microarrays are a powerful tool for identifying biomarkers indicating morbid obesity by analyzing differential gene expression profiles. This study confirms the association of PPARgamma with morbid obesity. Also, these findings in blood support previous work documented in tissue

  10. Integrin α6Bβ4 inhibits colon cancer cell proliferation and c-Myc activity

    International Nuclear Information System (INIS)

    Dydensborg, Anders Bondo; Teller, Inga C; Groulx, Jean-François; Basora, Nuria; Paré, Fréderic; Herring, Elizabeth; Gauthier, Rémy; Jean, Dominique; Beaulieu, Jean-François

    2009-01-01

    Integrins are known to be important contributors to cancer progression. We have previously shown that the integrin β4 subunit is up-regulated in primary colon cancer. Its partner, the integrin α6 subunit, exists as two different mRNA splice variants, α6A and α6B, that differ in their cytoplasmic domains but evidence for distinct biological functions of these α6 splice variants is still lacking. In this work, we first analyzed the expression of integrin α6A and α6B at the protein and transcript levels in normal human colonic cells as well as colorectal adenocarcinoma cells from both primary tumors and established cell lines. Then, using forced expression experiments, we investigated the effect of α6A and α6B on the regulation of cell proliferation in a colon cancer cell line. Using variant-specific antibodies, we observed that α6A and α6B are differentially expressed both within the normal adult colonic epithelium and between normal and diseased colonic tissues. Proliferative cells located in the lower half of the glands were found to predominantly express α6A, while the differentiated and quiescent colonocytes in the upper half of the glands and surface epithelium expressed α6B. A relative decrease of α6B expression was also identified in primary colon tumors and adenocarcinoma cell lines suggesting that the α6A/α6B ratios may be linked to the proliferative status of colonic cells. Additional studies in colon cancer cells showed that experimentally restoring the α6A/α6B balance in favor of α6B caused a decrease in cellular S-phase entry and repressed the activity of c-Myc. The findings that the α6Bβ4 integrin is expressed in quiescent normal colonic cells and is significantly down-regulated in colon cancer cells relative to its α6Aβ4 counterpart are consistent with the anti-proliferative influence and inhibitory effect on c-Myc activity identified for this α6Bβ4 integrin. Taken together, these findings point out the importance of integrin

  11. Designed modulation of sex steroid signaling inhibits telomerase activity and proliferation of human prostate cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Verma, Vikas; Sharma, Vikas; Singh, Vishal [Division of Endocrinology, CSIR-Central Drug Research Institute, Lucknow 226 031 (India); Sharma, Siddharth; Bishnoi, Ajay Kumar [Division of Medicinal and Process Chemistry, CSIR-Central Drug Research Institute, Lucknow 226 031 (India); Chandra, Vishal; Maikhuri, J.P.; Dwivedi, Anila [Division of Endocrinology, CSIR-Central Drug Research Institute, Lucknow 226 031 (India); Kumar, Atul [Division of Medicinal and Process Chemistry, CSIR-Central Drug Research Institute, Lucknow 226 031 (India); Gupta, Gopal, E-mail: g_gupta@cdri.res.in [Division of Endocrinology, CSIR-Central Drug Research Institute, Lucknow 226 031 (India)

    2014-10-15

    The predominant estrogen-receptor (ER)-β signaling in normal prostate is countered by increased ER-α signaling in prostate cancer (CaP), which in association with androgen-receptor (AR) signaling results in pathogenesis of the disease. However CaP treatments mostly target AR signaling which is initially effective but eventually leads to androgen resistance, hence simultaneous targeting of ERs has been proposed. A novel series of molecules were designed with multiple sex-steroid receptor modulating capabilities by coalescing the pharmacophores of known anti-CaP molecules that act via modulation of ER(α/β) and/or AR, viz. 3,3′diindolylmethane (DIM), mifepristone, toremifene, tamoxifen and raloxifene. N,N-diethyl-4-((2-(4-methoxyphenyl)-1H-indol-3-yl)methyl) aniline (DIMA) was identified as the most promising structure of this new series. DIMA increased annexin-V labelling, cell-cycle arrest and caspase-3 activity, and decreased expression of AR and prostate specific antigen in LNCaP cells, in vitro. Concurrently, DIMA increased ER-β, p21 and p27 protein levels in LNCaP cells and exhibited ∼ 5 times more selective binding for ER-β than ER-α, in comparison to raloxifene. DIMA exhibited a dose-dependent ER-β agonism and ER-α antagonism in classical gene reporter assay and decreased hTERT (catalytic subunit of telomerase) transcript levels in LNCaP at 3.0 μM (P < 0.05). DIMA also dose-dependently decreased telomerase enzyme activity in prostate cancer cells. It is thus concluded that DIMA acts as a multi-steroid receptor modulator and effectively inhibits proliferation of prostate cancer cells through ER-β mediated telomerase inhibition, by countering actions of ER-α and AR. Its unique molecular design can serve as a lead structure for generation of potent agents against endocrine malignancies like the CaP.

  12. Activation of IRE1α-XBP1 pathway induces cell proliferation and invasion in colorectal carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Chun [Department of Coloproctology, The Second Affiliated Hospital of Wenzhou Medical University, Wenzhou 325000 (China); Jin, Zhao [Department of Coloproctology, Wenzhou Hospital of Integrated Traditional Chinese and Western Medicine, Wenzhou 325000 (China); Chen, Nian-zhao [Department of Medicine, The Chinese Medicine Hospital of Wenzhou, Wenzhou 325000 (China); Lu, Min; Liu, Chang-bao; Hu, Wan-Le [Department of Coloproctology, The Second Affiliated Hospital of Wenzhou Medical University, Wenzhou 325000 (China); Zheng, Chen-guo, E-mail: zhengchenguo80@163.com [Department of Coloproctology, The Second Affiliated Hospital of Wenzhou Medical University, Wenzhou 325000 (China)

    2016-01-29

    Cell proliferation and tumor metastasis are considered as the main reasons for death in colorectal carcinoma (CRC). IRE1α-XBP1 pathway is the most conserved UPR pathways, which are activated during ER stress caused by the accumulation of unfolded or misfolded protein in the lumen of ER. Here, we demonstrated the critical role of IRE1α-XBP1 pathway and underlying molecular mechanism in cell proliferation and tumor metastasis in CRC. By the use of tissue microarray analysis of samples from 119 patients with CRC, IRE1α was determined to be an independent predictor of overall survival as higher expression of IRE1α in CRC patients showed lower survival rates (p = 0.0041). RNA interference and ectopic expression of IRE1α were applied to determine the molecular effects of IRE1α in CRC cells. The silencing of IRE1α inhibited the proliferation and blocked the invasion of CRC cells in vitro, while ectopic expression of IRE1α in turn promoted cell proliferation and invasion. IRE1α-XBP1 pathway regulated the mitosis of CRC cells through the directly binding of XBP1s to Cyclin D1 promoter to activate Cyclin D1 expression. Our results reveal that IRE1α-XBP1 pathway plays an important role in tumor progression and epithelial-to-mesenchymal transition (EMT), and IRE1α could be employed as a novel prognostic marker and a promising therapeutic target for CRC. - Highlights: • IRE1 was determined to be an independent predictor of overall survival in CRC patient. • IRE1-XBP1 pathway promoted CRC cell proliferation through regulating Cyclin D1 expression. • IRE1-XBP1 pathway played important role in EMT of CRC cells.

  13. Activation of IRE1α-XBP1 pathway induces cell proliferation and invasion in colorectal carcinoma

    International Nuclear Information System (INIS)

    Jin, Chun; Jin, Zhao; Chen, Nian-zhao; Lu, Min; Liu, Chang-bao; Hu, Wan-Le; Zheng, Chen-guo

    2016-01-01

    Cell proliferation and tumor metastasis are considered as the main reasons for death in colorectal carcinoma (CRC). IRE1α-XBP1 pathway is the most conserved UPR pathways, which are activated during ER stress caused by the accumulation of unfolded or misfolded protein in the lumen of ER. Here, we demonstrated the critical role of IRE1α-XBP1 pathway and underlying molecular mechanism in cell proliferation and tumor metastasis in CRC. By the use of tissue microarray analysis of samples from 119 patients with CRC, IRE1α was determined to be an independent predictor of overall survival as higher expression of IRE1α in CRC patients showed lower survival rates (p = 0.0041). RNA interference and ectopic expression of IRE1α were applied to determine the molecular effects of IRE1α in CRC cells. The silencing of IRE1α inhibited the proliferation and blocked the invasion of CRC cells in vitro, while ectopic expression of IRE1α in turn promoted cell proliferation and invasion. IRE1α-XBP1 pathway regulated the mitosis of CRC cells through the directly binding of XBP1s to Cyclin D1 promoter to activate Cyclin D1 expression. Our results reveal that IRE1α-XBP1 pathway plays an important role in tumor progression and epithelial-to-mesenchymal transition (EMT), and IRE1α could be employed as a novel prognostic marker and a promising therapeutic target for CRC. - Highlights: • IRE1 was determined to be an independent predictor of overall survival in CRC patient. • IRE1-XBP1 pathway promoted CRC cell proliferation through regulating Cyclin D1 expression. • IRE1-XBP1 pathway played important role in EMT of CRC cells.

  14. RhoA–Rho kinase and Platelet Activating Factor Stimulation of Ovine Fetal Pulmonary Vascular Smooth Muscle Cell Proliferation

    Science.gov (United States)

    Renteria, Lissette S.; Austin, Monique; Lazaro, Mariecon; Andrews, Mari Ashley; Lustina, Jennessee; Raj, J. Usha; Ibe, Basil O.

    2013-01-01

    Objectives Platelet Activating Factor (PAF) is produced by pulmonary vascular smooth muscle Cells (PVSMC). We studied effect of Rho kinase on PAF stimulation of PVSMC proliferation in an attempt to understand a role for RhoA/Rho kinase on PAF-induced ovine fetal pulmonary vascular remodeling. Our hypothesis is that PAF acts through Rho kinase, as one of its downstream signaling, to induce arterial (SMC-PA) and venous (SMC-PV) growth in the hypoxic lung environment of the fetus in utero. Materials and methods Rho kinase and MAPK effects on PAF receptor (PAFR)-mediated cell growth and PAFR expression were studied by DNA synthesis, Western and immunocytochemistry. Effects of constructs T19N and G14V on PAF-induced cell proliferation was also studied. Results Hypoxia increased PVSMC proliferation and the Rho kinase inhibitors, Y-27632 and Fasudil (HA-1077) as well as MAPK inhibitors PD 98059 and SB 203580 attenuated PAF stimulation of cell proliferation. RhoA T19N and G14V stimulated cell proliferation, but co-incubation with PAF did not affect proliferative effects of the constructs. PAFR protein expression was significantly down-regulated in both cell types by both Y-27632 and HA-1077 with comparable profiles. Also cells treated with Y-27632 showed less PAF receptor fluorescence with significant disruption of the cell morphology. Conclusions Our results show that Rho kinase nonspecifically modulates PAFR-mediated responses via a translational modification of PAFR protein and suggest that, in vivo, activation of Rho kinase by PAF may be one other pathway to sustain PAFR-mediated PVSMC growth. PMID:24033386

  15. A rhodanine derivative CCR-11 inhibits bacterial proliferation by inhibiting the assembly and GTPase activity of FtsZ.

    Science.gov (United States)

    Singh, Parminder; Jindal, Bhavya; Surolia, Avadhesha; Panda, Dulal

    2012-07-10

    A perturbation of FtsZ assembly dynamics has been shown to inhibit bacterial cytokinesis. In this study, the antibacterial activity of 151 rhodanine compounds was assayed using Bacillus subtilis cells. Of 151 compounds, eight strongly inhibited bacterial proliferation at 2 μM. Subsequently, we used the elongation of B. subtilis cells as a secondary screen to identify potential FtsZ-targeted antibacterial agents. We found that three compounds significantly increased bacterial cell length. One of the three compounds, namely, CCR-11 [(E)-2-thioxo-5-({[3-(trifluoromethyl)phenyl]furan-2-yl}methylene)thiazolidin-4-one], inhibited the assembly and GTPase activity of FtsZ in vitro. CCR-11 bound to FtsZ with a dissociation constant of 1.5 ± 0.3 μM. A docking analysis indicated that CCR-11 may bind to FtsZ in a cavity adjacent to the T7 loop and that short halogen-oxygen, H-bonding, and hydrophobic interactions might be important for the binding of CCR-11 with FtsZ. CCR-11 inhibited the proliferation of B. subtilis cells with a half-maximal inhibitory concentration (IC(50)) of 1.2 ± 0.2 μM and a minimal inhibitory concentration of 3 μM. It also potently inhibited proliferation of Mycobacterium smegmatis cells. Further, CCR-11 perturbed Z-ring formation in B. subtilis cells; however, it neither visibly affected nucleoid segregation nor altered the membrane integrity of the cells. CCR-11 inhibited HeLa cell proliferation with an IC(50) value of 18.1 ± 0.2 μM (∼15 × IC(50) of B. subtilis cell proliferation). The results suggested that CCR-11 inhibits bacterial cytokinesis by inhibiting FtsZ assembly, and it can be used as a lead molecule to develop FtsZ-targeted antibacterial agents.

  16. Peroxisome proliferator-activated receptor delta (PPARdelta) activation protects H9c2 cardiomyoblasts from oxidative stress-induced apoptosis.

    Science.gov (United States)

    Pesant, Matthieu; Sueur, Stéphanie; Dutartre, Patrick; Tallandier, Mireille; Grimaldi, Paul A; Rochette, Luc; Connat, Jean-Louis

    2006-02-01

    Activation of peroxisome proliferator-activated receptor alpha (PPARalpha) and PPARgamma plays beneficial roles in cardiovascular disorders such as atherosclerosis and heart reperfusion. Although PPARalpha and gamma have been documented to reduce oxidative stress in the vasculature and the heart, the role of PPARdelta remains poorly studied. We focused on PPARdelta function in the regulation of oxidative stress-induced apoptosis in the rat cardiomyoblast cell line H9c2. Using semi-quantitative reverse transcriptase-polymerase chain reaction (RT-PCR), we showed that PPARdelta is the predominantly expressed isotype whereas PPARalpha was weakly detected. By performing cell viability assays, we also showed that the selective PPARdelta agonist GW501516 protected cells from H(2)O(2)-induced cell death. The protective effect of GW501516 was due to an inhibition of H(2)O(2)-triggered apoptosis as shown by annexin-V labeling, DNA fragmentation analysis, and caspase-3 activity measurement. We demonstrated by transient transfection of a dominant negative mutant of PPARdelta that the protection induced by GW501516 was totally dependent on PPARdelta. Semi-quantitative RT-PCR and Western blotting analysis demonstrated that GW501516 treatment upregulated catalase. Moreover, forced overexpression of catalase inhibited H(2)O(2)-triggered apoptosis, as evidenced by annexin-V labeling. Taken together, our results account for an important role of PPARdelta in inhibiting the onset of oxidative stress-induced apoptosis in H9c2 cells. PPARdelta appears to be a new therapeutic target for the regulation of heart reperfusion-associated oxidative stress and stimulation of enzymatic antioxidative defences.

  17. Activation of peroxisome proliferator-activated receptor gamma by rosiglitazone increases sirt6 expression and ameliorates hepatic steatosis in rats.

    Directory of Open Access Journals (Sweden)

    Soo Jin Yang

    Full Text Available BACKGROUND: Sirt6 has been implicated in the regulation of hepatic lipid metabolism and the development of hepatic steatosis. The aim of this study was to address the potential role of Sirt6 in the protective effects of rosiglitazone (RGZ on hepatic steatosis. METHODS: To investigate the effect of RGZ on hepatic steatosis, rats were treated with RGZ (4 mg·kg⁻¹·day⁻¹ by stomach gavage for 6 weeks. The involvement of Sirt6 in the RGZ's regulation was evaluated by Sirt6 knockdown in AML12 mouse hepatocytes. RESULTS: RGZ treatment ameliorated hepatic lipid accumulation and increased expression of Sirt6, peroxisome proliferator-activated receptor gamma coactivtor-1-α (Ppargc1a/PGC1-α and Forkhead box O1 (Foxo1 in rat livers. AMP-activated protein kinase (AMPK phosphorylation was also increased by RGZ, accompanied by alterations in phosphorylation of LKB1. Interestingly, in free fatty acid-treated cells, Sirt6 knockdown increased hepatocyte lipid accumulation measured as increased triglyceride contents (p = 0.035, suggesting that Sirt6 may be beneficial in reducing hepatic fat accumulation. In addition, Sirt6 knockdown abolished the effects of RGZ on hepatocyte fat accumulation, mRNA and protein expression of Ppargc1a/PGC1-α and Foxo1, and phosphorylation levels of LKB1 and AMPK, suggesting that Sirt6 is involved in RGZ-mediated metabolic effects. CONCLUSION: Our results demonstrate that RGZ significantly decreased hepatic lipid accumulation, and that this process appeared to be mediated by the activation of the Sirt6-AMPK pathway. We propose Sirt6 as a possible therapeutic target for hepatic steatosis.

  18. Fenofibrate inhibited pancreatic cancer cells proliferation via activation of p53 mediated by upregulation of LncRNA MEG3

    International Nuclear Information System (INIS)

    Hu, Duanmin; Su, Cunjin; Jiang, Min; Shen, Yating; Shi, Aiming; Zhao, Fenglun; Chen, Ruidong; Shen, Zhu; Bao, Junjie; Tang, Wen

    2016-01-01

    There is still no suitable drug for pancreatic cancer treatment, which is one of the most aggressive human tumors. Maternally expressed gene 3 (MEG3), a LncRNA, has been suggested as a tumor suppressor in a range of human tumors. Studies found fenofibrate exerted anti-tumor roles in various human cancer cell lines. However, its role in pancreatic cancer remains unknown. The present study aimed to explore the impacts of fenofibrate on pancreatic cancer cell lines, and to investigate MEG3 role in its anti-tumor mechanisms. We used MTT assay to determine cells proliferation, genome-wide LncRNA microarray analysis to identify differently expressed LncRNAs, siRNA or pCDNA-MEG3 transfection to interfere or upregulate MEG3 expression, western blot to detect protein levels, real-time PCR to determine MEG3 level. Fenofibrate significantly inhibited proliferation of pancreatic cancer cells, increased MEG3 expression and p53 levels. Moreover, knockdown of MEG3 attenuated cytotoxicity induced by fenofibrate. Furthermore, overexpression of MEG3 induced cells death and increased p53 expression. Our results indicated fenofibrate inhibited pancreatic cancer cells proliferation via activation of p53 mediated by upregulation of MEG3. - Highlights: • We found that fenofibrate suppressed proliferation of pancreatic cancer cells. • We found fenofibrate increased LncRNA-MEG3 expression and p53 level in PANC-1 cells. • Inhibition of MEG3 expression attenuated anti-tumor effects of fenofibrate.

  19. Fenofibrate inhibited pancreatic cancer cells proliferation via activation of p53 mediated by upregulation of LncRNA MEG3

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Duanmin [Department of Gastroenterology, The Second Affiliated Hospital of Soochow University, Suzhou 215004 (China); Su, Cunjin [Department of Pharmacy, The Second Affiliated Hospital of Soochow University, Suzhou 215004 (China); Jiang, Min [Department of Breast Surgery, The First Affiliated Hospital of Soochow University, Suzhou 215004 (China); Shen, Yating [Department of Gastroenterology, The Second Affiliated Hospital of Soochow University, Suzhou 215004 (China); Shi, Aiming; Zhao, Fenglun [Department of Pharmacy, The Second Affiliated Hospital of Soochow University, Suzhou 215004 (China); Chen, Ruidong [Department of Gastroenterology, The Second Affiliated Hospital of Soochow University, Suzhou 215004 (China); Shen, Zhu [Department of Pharmacy, The Second Affiliated Hospital of Soochow University, Suzhou 215004 (China); Bao, Junjie, E-mail: baojjsdfey@sina.com [Department of Pharmacy, The Second Affiliated Hospital of Soochow University, Suzhou 215004 (China); Tang, Wen, E-mail: sztangwen@163.com [Department of Gastroenterology, The Second Affiliated Hospital of Soochow University, Suzhou 215004 (China)

    2016-03-04

    There is still no suitable drug for pancreatic cancer treatment, which is one of the most aggressive human tumors. Maternally expressed gene 3 (MEG3), a LncRNA, has been suggested as a tumor suppressor in a range of human tumors. Studies found fenofibrate exerted anti-tumor roles in various human cancer cell lines. However, its role in pancreatic cancer remains unknown. The present study aimed to explore the impacts of fenofibrate on pancreatic cancer cell lines, and to investigate MEG3 role in its anti-tumor mechanisms. We used MTT assay to determine cells proliferation, genome-wide LncRNA microarray analysis to identify differently expressed LncRNAs, siRNA or pCDNA-MEG3 transfection to interfere or upregulate MEG3 expression, western blot to detect protein levels, real-time PCR to determine MEG3 level. Fenofibrate significantly inhibited proliferation of pancreatic cancer cells, increased MEG3 expression and p53 levels. Moreover, knockdown of MEG3 attenuated cytotoxicity induced by fenofibrate. Furthermore, overexpression of MEG3 induced cells death and increased p53 expression. Our results indicated fenofibrate inhibited pancreatic cancer cells proliferation via activation of p53 mediated by upregulation of MEG3. - Highlights: • We found that fenofibrate suppressed proliferation of pancreatic cancer cells. • We found fenofibrate increased LncRNA-MEG3 expression and p53 level in PANC-1 cells. • Inhibition of MEG3 expression attenuated anti-tumor effects of fenofibrate.

  20. Regulation of the human SLC25A20 expression by peroxisome proliferator-activated receptor alpha in human hepatoblastoma cells

    Energy Technology Data Exchange (ETDEWEB)

    Tachibana, Keisuke, E-mail: nya@phs.osaka-u.ac.jp [Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita, Osaka 565-0871 (Japan); Takeuchi, Kentaro; Inada, Hirohiko [Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita, Osaka 565-0871 (Japan); Yamasaki, Daisuke [Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita, Osaka 565-0871 (Japan); The Center for Advanced Medical Engineering and Informatics, Osaka University, 2-2 Yamadaoka, Suita, Osaka 565-0871 (Japan); Ishimoto, Kenji [Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita, Osaka 565-0871 (Japan); Graduate School of Medicine, Osaka University, 2-2 Yamadaoka, Suita, Osaka 565-0871 (Japan); Tanaka, Toshiya; Hamakubo, Takao; Sakai, Juro; Kodama, Tatsuhiko [Laboratory for System Biology and Medicine, Research Center for Advanced Science and Technology, University of Tokyo, 4-6-1 Komaba, Meguro, Tokyo 153-8904 (Japan); Doi, Takefumi [Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita, Osaka 565-0871 (Japan); The Center for Advanced Medical Engineering and Informatics, Osaka University, 2-2 Yamadaoka, Suita, Osaka 565-0871 (Japan); Graduate School of Medicine, Osaka University, 2-2 Yamadaoka, Suita, Osaka 565-0871 (Japan)

    2009-11-20

    Solute carrier family 25, member 20 (SLC25A20) is a key molecule that transfers acylcarnitine esters in exchange for free carnitine across the mitochondrial membrane in the mitochondrial {beta}-oxidation. The peroxisome proliferator-activated receptor alpha (PPAR{alpha}) is a ligand-activated transcription factor that plays an important role in the regulation of {beta}-oxidation. We previously established tetracycline-regulated human cell line that can be induced to express PPAR{alpha} and found that PPAR{alpha} induces the SLC25A20 expression. In this study, we analyzed the promoter region of the human slc25a20 gene and showed that PPAR{alpha} regulates the expression of human SLC25A20 via the peroxisome proliferator responsive element.

  1. Reduced RAC1 activity inhibits cell proliferation and induces apoptosis in neurofibromatosis type 2(NF2)-associated schwannoma.

    Science.gov (United States)

    Wang, Ying; Wang, Bo; Li, Peng; Zhang, Qi; Liu, Pinan

    2017-12-01

    Objective To study the function and potential mechanism of RAC1 inhibitors in NF2-associated schwannoma. Methods In this study, we the downregulation of RAC1 activity and tumor cell phenotypes by RAC1 inhibitor NSC23766 in vitro. And we further validated the anti-proliferation effect by this RAC1 inhibitor in subcutaneous xenograft tumor model and sciatic nerve model. Results Pharmacological inhibition of RAC1 could significantly inhibit the proliferation of both RT4 cells and human NF2-associated primary schwannoma cells by inducing apoptosis. Pharmacological inhibition of RAC1 effectively reduced Rac1 activity and down-regulated the pathway downstream of Rac. Moreover, pharmacological inhibition of RAC1 showed a potential antitumor effect, with low toxicity in vivo. Conclusion RAC1 inhibitors may play a therapeutic role in patients with schwannoma.

  2. Regulation of the human SLC25A20 expression by peroxisome proliferator-activated receptor alpha in human hepatoblastoma cells

    International Nuclear Information System (INIS)

    Tachibana, Keisuke; Takeuchi, Kentaro; Inada, Hirohiko; Yamasaki, Daisuke; Ishimoto, Kenji; Tanaka, Toshiya; Hamakubo, Takao; Sakai, Juro; Kodama, Tatsuhiko; Doi, Takefumi

    2009-01-01

    Solute carrier family 25, member 20 (SLC25A20) is a key molecule that transfers acylcarnitine esters in exchange for free carnitine across the mitochondrial membrane in the mitochondrial β-oxidation. The peroxisome proliferator-activated receptor alpha (PPARα) is a ligand-activated transcription factor that plays an important role in the regulation of β-oxidation. We previously established tetracycline-regulated human cell line that can be induced to express PPARα and found that PPARα induces the SLC25A20 expression. In this study, we analyzed the promoter region of the human slc25a20 gene and showed that PPARα regulates the expression of human SLC25A20 via the peroxisome proliferator responsive element.

  3. Bile acids induce hepatic stellate cell proliferation via activation of the epidermal growth factor receptor

    NARCIS (Netherlands)

    Svegliati-Baroni, G; Ridolfi, F; Hannivoort, R; Saccomanno, S; Homan, M; De Minicis, S; Jansen, PLM; Candelaresi, C; Benedetti, A; Moshage, H

    Background B Aims: Hepatic stellate cell (HSC) proliferation is a key event in the development of liver fibrosis. In many liver diseases, HSCs are exposed to inflammatory cytokines, reactive oxygen species, and bile acids. Although inflammatory cytokines and reactive oxygen species are known to

  4. Bile acids induce hepatic stellate cell proliferation via activation of the epidermal growth factor receptor

    NARCIS (Netherlands)

    Svegliati-Baroni, Gianluca; Ridolfi, Francesco; Hannivoort, Rebekka; Saccomanno, Stefania; Homan, Manon; de Minicis, Samuele; Jansen, Peter L. M.; Candelaresi, Cinzia; Benedetti, Antonio; Moshage, Han

    2005-01-01

    BACKGROUND & AIMS: Hepatic stellate cell (HSC) proliferation is a key event in the development of liver fibrosis. In many liver diseases, HSCs are exposed to inflammatory cytokines, reactive oxygen species, and bile acids. Although inflammatory cytokines and reactive oxygen species are known to

  5. Effects of activated and nonactivated platelet-rich plasma on proliferation of human osteoblasts in vitro

    Czech Academy of Sciences Publication Activity Database

    Slapnička, J.; Fassmann, A.; Strašák, Luděk; Augustin, P.; Vaněk, J.

    2008-01-01

    Roč. 66, č. 2 (2008), s. 297-301 ISSN 0278-2391 Institutional research plan: CEZ:AV0Z50040507; CEZ:AV0Z50040702 Keywords : platelet-rich plasma * osteoblast * proliferation Subject RIV: BO - Biophysics Impact factor: 1.241, year: 2008

  6. Apoptosis as a post-phagocytic winnowing mechanism in a coral-dinoflagellate mutualism.

    Science.gov (United States)

    Dunn, Simon R; Weis, Virginia M

    2009-01-01

    This study was aimed at detecting apoptosis as a post-phagocytic mechanism of symbiont selection during the onset of symbiosis in larvae of the scleractinian coral Fungia scutaria. Larvae were infected with one of three Symbiodinium types: freshly isolated homologous ITS-type C1f from adult F. scutaria, heterologous C31 from adult Montipora capitata, known to be unable to successfully colonize F. scutaria larvae, and type B1 from the symbiotic sea anemone Aiptasia spp. Apoptosis was detected by the activation of caspases, enzymes specific to apoptosis. Caspase activity was measured in situ by cleavage of a specific fluorophore and detection with confocal microscopy. At 6 h post infection, there was a significant increase in caspase activation in gastrodermal cells in C31-infected larvae, compared with larvae infected with C1f or B1 types. Compared with control larvae infected with C31, which had decreased infection rates present by 24 h post infection, when C31-infected larvae were incubated with a broad-scale caspase inhibitor, the per cent of larvae infected with C31 did not significantly decrease over time. This indicates that the reduction in infection success observed in untreated C31-infected larvae can be rescued with inhibition of caspases and apoptosis. This suggests the presence of a post-phagocytic recognition mechanism. Larvae infected with freshly isolated B1 retained infection success over time compared with C31-infected larvae, suggesting that there is host discrimination between heterologous algae. Initiation of this post-phagocytic response may occur more readily with a highly specific heterologous symbiont type such as C31, compared with a generalist heterologous type such as clade B1.

  7. Fibrates suppress bile acid synthesis via peroxisome proliferator-activated receptor-α-mediated downregulation of cholesterol 7α-hydroxylase and sterol 27-hydroxylase expression

    NARCIS (Netherlands)

    Post, S.M.; Duez, H.; Gervois, P.P.; Staels, B.; Kuipers, F.; Princen, H.M.G.

    2001-01-01

    Fibrates are hypolipidemic drugs that affect the expression of genes involved in lipid metabolism by activating peroxisome proliferator-activated receptors (PPARs). Fibrate treatment causes adverse changes in biliary lipid composition and decreases bile acid excretion, leading to an increased

  8. Fibrates suppress bile acid synthesis via peroxisome proliferator-activated receptor-alpha-mediated downregulation of cholesterol 7 alpha-hydroxylase and sterol 27-hydroxylase expression

    NARCIS (Netherlands)

    Post, SM; Duez, H; Gervois, PP; Staels, B; Kuipers, F; Princen, HMG

    2001-01-01

    Fibrates are hypolipidemic drugs that affect the expression of genes involved in lipid metabolism by activating peroxisome proliferator-activated receptors (PPARs). Fibrate treatment causes adverse changes in biliary lipid composition and decreases bile acid excretion, leading to an increased

  9. Lipopolysaccharide induces proliferation and osteogenic differentiation of adipose-derived mesenchymal stromal cells in vitro via TLR4 activation

    Energy Technology Data Exchange (ETDEWEB)

    Herzmann, Nicole; Salamon, Achim [Department of Cell Biology, University Medicine Rostock, Schillingallee 69, D-18057 Rostock (Germany); Fiedler, Tomas [Institute for Medical Microbiology, Virology and Hygiene, University Medicine Rostock, Schillingallee 70, D-18057 Rostock (Germany); Peters, Kirsten, E-mail: kirsten.peters@med.uni-rostock.de [Department of Cell Biology, University Medicine Rostock, Schillingallee 69, D-18057 Rostock (Germany)

    2017-01-01

    Multipotent mesenchymal stromal cells (MSC) are capable of multi-lineage differentiation and support regenerative processes. In bacterial infections, resident MSC can come intocontact with and need to react to bacterial components. Lipopolysaccharide (LPS), a typical structure of Gram-negative bacteria, increases the proliferation and osteogenic differentiation of MSC. LPS is usually recognized by the toll-like receptor (TLR) 4 and induces pro-inflammatory reactions in numerous cell types. In this study, we quantified the protein expression of TLR4 and CD14 on adipose-derived MSC (adMSC) in osteogenic differentiation and investigated the effect of TLR4 activation by LPS on NF-κB activation, proliferation and osteogenic differentiation of adMSC. We found that TLR4 is expressed on adMSC whereas CD14 is not, and that osteogenic differentiation induced an increase of the amount of TLR4 protein whereas LPS stimulation did not. Moreover, we could show that NF-κB activation via TLR4 occurs upon LPS treatment. Furthermore, we were able to show that competitive inhibition of TLR4 completely abolished the stimulatory effect of LPS on the proliferation and osteogenic differentiation of adMSC. In addition, the inhibition of TLR4 leads to the complete absence of osteogenic differentiation of adMSC, even when osteogenically stimulated. Thus, we conclude that LPS induces proliferation and osteogenic differentiation of adMSC in vitro through the activation of TLR4 and that the TLR4 receptor seems to play a role during osteogenic differentiation of adMSC.

  10. Exercise reduces adipose tissue via cannabinoid receptor type 1 which is regulated by peroxisome proliferator-activated receptor-delta

    DEFF Research Database (Denmark)

    Yan, Zhen Cheng; Liu, Dao Yan; Zhang, Li Li

    2007-01-01

    Obesity is one major cardiovascular risk factor. We tested effects of endurance exercise on cannabinoid receptor type 1 (CB1) and peroxisome proliferator-activated receptor-delta (PPAR-delta)-dependent pathways in adipose tissue. Male Wistar rats were randomly assigned to standard laboratory chow...... or a high-fat diet without and with regular endurance exercise. Exercise in rats on high-fat diet significantly reduced visceral fat mass, blood pressure, and adipocyte size (each p...

  11. Adiponectin and AMP kinase activator stimulate proliferation, differentiation, and mineralization of osteoblastic MC3T3-E1 cells

    Directory of Open Access Journals (Sweden)

    Yamauchi Mika

    2007-11-01

    Full Text Available Abstract Background Adiponectin is a key mediator of the metabolic syndrome that is caused by visceral fat accumulation. Adiponectin and its receptors are known to be expressed in osteoblasts, but their actions with regard to bone metabolism are still unclear. In this study, we investigated the effects of adiponectin on the proliferation, differentiation, and mineralization of osteoblastic MC3T3-E1 cells. Results Adiponectin receptor type 1 (AdipoR1 mRNA was detected in the cells by RT-PCR. The adenosine monophosphate-activated protein kinase (AMP kinase was phosphorylated by both adiponectin and a pharmacological AMP kinase activator, 5-amino-imidazole-4-carboxamide-riboside (AICAR, in the cells. AdipoR1 small interfering RNA (siRNA transfection potently knocked down the receptor mRNA, and the effect of this knockdown persisted for as long as 10 days after the transfection. The transfected cells showed decreased expressions of type I collagen and osteocalcin mRNA, as determined by real-time PCR, and reduced ALP activity and mineralization, as determined by von Kossa and Alizarin red stainings. In contrast, AMP kinase activation by AICAR (0.01–0.5 mM in wild-type MC3T3-E1 cells augmented their proliferation, differentiation, and mineralization. BrdU assay showed that the addition of adiponectin (0.01–1.0 μg/ml also promoted their proliferation. Osterix, but not Runx-2, appeared to be involved in these processes because AdipoR1 siRNA transfection and AICAR treatments suppressed and enhanced osterix mRNA expression, respectively. Conclusion Taken together, this study suggests that adiponectin stimulates the proliferation, differentiation, and mineralization of osteoblasts via the AdipoR1 and AMP kinase signaling pathways in autocrine and/or paracrine fashions.

  12. Expression of Peroxisome Proliferator-Activated Receptor-γ in Key Neuronal Subsets Regulating Glucose Metabolism and Energy Homeostasis

    OpenAIRE

    Sarruf, David A.; Yu, Fang; Nguyen, Hong T.; Williams, Diana L.; Printz, Richard L.; Niswender, Kevin D.; Schwartz, Michael W.

    2008-01-01

    In addition to increasing insulin sensitivity and adipogenesis, peroxisome proliferator-activated receptor (PPAR)-γ agonists cause weight gain and hyperphagia. Given the central role of the brain in the control of energy homeostasis, we sought to determine whether PPARγ is expressed in key brain areas involved in metabolic regulation. Using immunohistochemistry, PPARγ distribution and its colocalization with neuron-specific protein markers were investigated in rat and mouse brain sections spa...

  13. Plasma rich in growth factors promotes dermal fibroblast proliferation, migration and biosynthetic activity.

    Science.gov (United States)

    Anitua, E; Pino, A; Orive, G

    2016-11-02

    The use of plasma rich in growth factors (PRGF) has gained importance in many medical fields due to its regenerative potential. The aim of this study is to evaluate the effects of PRGF on primary skin fibroblasts assessing cell proliferation, migration and secretion of growth factors. The age of the patients from who PRGF was prepared was also studied to determine whether it influenced the outcomes. Human dermal fibroblasts were isolated from three healthy volunteers. Using PRGF-Endoret technology, PRGF was prepared from two groups of different ages (18-35 years and 50+ years). The effects of increasing concentration of PRGF (5%, 10% and 20%) on cell proliferation and migration was evaluated. Biosynthetic behaviour of cells was also analysed measuring vascular endothelial growth factor (VEGF), transforming growth factor b1 (TGFb1) and pro-collagen type I secreted levels with or without PRGF treatment. Mean platelet enrichment reached 2.4X and 2X in 18-35 and 50+ groups respectively. A dose-dependent response was observed in proliferation assays achieving the highest levels with 20% PRGF. Migration was also promoted in cells but not in a dose-dependent manner. Cell proliferation and migration outcomes obtained with PRGF (from both groups) were significantly higher compared to non-stimulated groups (pPRGF, however, with the exception of VEGF, no statistical significances were observed between the different age groups. Results from this study concluded that PRGF is safe and effective in stimulating skin regeneration by enhancing proliferation, migration and expression of pivotal bioactive molecules involved in wound healing and haemostasis.

  14. Galangin suppresses HepG2 cell proliferation by activating the TGF-β receptor/Smad pathway

    International Nuclear Information System (INIS)

    Wang, Yajun; Wu, Jun; Lin, Biyun; Li, Xv; Zhang, Haitao; Ding, Hang; Chen, Xiaoyi; Lan, Liubo; Luo, Hui

    2014-01-01

    Galangin can suppress hepatocellular carcinoma (HCC) cell proliferation. In this study, we demonstrated that galangin induced autophagy by activating the transforming growth factor (TGF)-β receptor/Smad pathway and increased TGF-β receptor I (RI), TGF-βRII, Smad1, Smad2, Smad3 and Smad4 levels but decreased Smad6 and Smad7 levels. Autophagy induced by galangin appears to depend on the TGF-β receptor/Smad signalling pathway because the down-regulation of Smad4 by siRNA or inhibition of TGF-β receptor activation by LY2109761 blocked galangin-induced autophagy. The down-regulation of Beclin1, autophagy-related gene (ATG) 16L, ATG12 and ATG3 restored HepG2 cell proliferation and prevented galangin-induced apoptosis. Our findings indicate a novel mechanism for galangin-induced autophagy via activation of the TGF-β receptor/Smad pathway. The induction of autophagy thus reflects the anti-proliferation effect of galangin on HCC cells

  15. Ubiquitin carboxyl terminal hydrolase L1 negatively regulates TNFα-mediated vascular smooth muscle cell proliferation via suppressing ERK activation

    International Nuclear Information System (INIS)

    Ichikawa, Tomonaga; Li, Jinqing; Dong, Xiaoyu; Potts, Jay D.; Tang, Dong-Qi; Li, Dong-Sheng; Cui, Taixing

    2010-01-01

    Deubiquitinating enzymes (DUBs) appear to be critical regulators of a multitude of processes such as proliferation, apoptosis, differentiation, and inflammation. We have recently demonstrated that a DUB of ubiquitin carboxyl terminal hydrolase L1 (UCH-L1) inhibits vascular lesion formation via suppressing inflammatory responses in vasculature. However, the precise underlying mechanism remains to be defined. Herein, we report that a posttranscriptional up-regulation of UCH-L1 provides a negative feedback to tumor necrosis factor alpha (TNFα)-mediated activation of extracellular signal-regulated kinases (ERK) and proliferation in vascular smooth muscle cells (VSMCs). In rat adult VSMCs, adenoviral over-expression of UCH-L1 inhibited TNFα-induced activation of ERK and DNA synthesis. In contrast, over-expression of UCH-L1 did not affect platelet derived growth factor (PDGF)-induced VSMC proliferation and activation of growth stimulating cascades including ERK. TNFα hardly altered UCH-L1 mRNA expression and stability; however, up-regulated UCH-L1 protein expression via increasing UCH-L1 translation. These results uncover a novel mechanism by which UCH-L1 suppresses vascular inflammation.

  16. Identification of bioactive compounds from flowers of black elder (Sambucus nigra L.) that activate the human peroxisome proliferator-activated receptor (PPAR) gamma

    DEFF Research Database (Denmark)

    Christensen, Kathrine B; Petersen, Rasmus K; Kristiansen, Karsten

    2010-01-01

    Obesity is one of the predisposing factors for the development of overt Type 2 diabetes (T2D). T2D is caused by a combination of insulin resistance and beta-cell failure and can be treated with insulin sensitizing drugs that target the nuclear receptor peroxisome proliferator-activated receptor (...

  17. Adenosine: an activity-dependent axonal signal regulating MAP kinase and proliferation in developing Schwann cells

    OpenAIRE

    Stevens, Beth; Ishibashi, Tomoko; Chen, Jiang-Fan; Fields, R. Douglas

    2004-01-01

    Nonsynaptic release of ATP from electrically stimulated dorsal root gangion (DRG) axons inhibits Schwann cell (SC) proliferation and arrests SC development at the premyelinating stage, but the specific types of purinergic receptor(s) and intracellular signaling pathways involved in this form of neuron–glia communication are not known. Recent research shows that adenosine is a neuron–glial transmitter between axons and myelinating glia of the CNS. The present study investigates the possibility...

  18. Report on Activities and Programs for Countering Proliferation and NBC Terrorism. Volume 1. Executive Summary

    Science.gov (United States)

    2011-05-01

    protect our homeland. Protect our economic vitality through enhanced security of the U.S. transportation sector. Work with foreign counterparts...34,597 garments. Since FY09, the Joint Service Aircrew Mask-Rotary Wing (JSAM-RW), Mask Protection Unit-6/P ( MPU -6/P) Apache attack helicopter...the political, economic , cultural, and other security issues related to counterproliferation. Counter Proliferation. Encourage CP professionals

  19. Swelling-activated ion channels: functional regulation in cell-swelling, proliferation and apoptosis

    DEFF Research Database (Denmark)

    Stutzin, A; Hoffmann, E K

    2006-01-01

    Cell volume regulation is one of the most fundamental homeostatic mechanisms and essential for normal cellular function. At the same time, however, many physiological mechanisms are associated with regulatory changes in cell size meaning that the set point for cell volume regulation is under phys...... as key players in the maintenance of normal steady-state cell volume, with particular emphasis on the intracellular signalling pathways responsible for their regulation during hypotonic stress, cell proliferation and apoptosis....

  20. Chemical characteristics and anti-proliferation activities of Ganoderma tsugae polysaccharides.

    Science.gov (United States)

    Chien, Rao-Chi; Yen, Ming-Tsung; Tseng, Yu-Hsiu; Mau, Jeng-Leun

    2015-09-05

    Polysaccharides were extracted by hot-water and hot-alkali from four forms of Ganoderma tsugae including mature and baby Ling chih, mycelium and filtrate. Different profiles of proximate composition and monosaccharide constituents, and element contents were found in the extracted polysaccharides from different extractions and different forms. The molecular weight distributions of polysaccharides were 2.8×10(4)-6.5×10(5)Da and their infrared spectra were comparable. The hot-alkali extracted polysaccharides exhibited better anti-proliferation on IMR32 cells than the hot-water extracted polysaccharides, which were in turn more effective than the hot-water extracts. Besides, most hot-water extracts and both extracted polysaccharides exhibited an anti-proliferation effect on Hep G2 cells. However, the hot-water extracts showed less effective in anti-proliferation of IMR32 and Hep G2 cells. Based on the anti-tumor effects, both polysaccharides could be prepared for use in the formulation of nutraceuticals and functional foods. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. How important is the myeloperoxidase microbicidal system of phagocytic cells?

    Science.gov (United States)

    Thong, Y H

    1982-03-01

    The myeloperoxidase system is presented by most immunology textbooks as a major microbicidal system of phagocytic cells. This theory, however, has not bee subjected to vigorous testing in the clinical arena. Of 14 patients with primary myeloperoxidase deficiency, only 3 had infectious complication. All 3 patients have more plausible explanation than myeloperoxidase deficiency for their infectious complications. Two of these patients were healthy until middle age when they developed systemic candidiasis after the onset of diabetes mellitus. The third patient was an infant with a maturational defect in neutrophil chemotaxis whose infectious complications ceased after the normalization of the chemotactic defect. The results of these "experiments of nature" indicate that the meyloperoxidase system is not a major microbicidal mechanism of phagocytic cells.

  2. Pirfenidone inhibits the proliferation of fibroblasts from patients with active Crohn's disease.

    Science.gov (United States)

    Kadir, Sara-Irini; Wenzel Kragstrup, Tue; Dige, Anders; Kok Jensen, Simon; Dahlerup, Jens Frederik; Kelsen, Jens

    2016-11-01

    One-third of Crohn's disease (CD) patients develop intestinal strictures that require repeated surgical intervention. Current anti-inflammatory therapies have limited effect on stricture development, which necessitates the exploration of new pharmacological approaches. Pirfenidone (PFD), a novel anti-fibrotic agent, was recently approved in Europe for the treatment of idiopathic pulmonary fibrosis (IPF). We hypothesized that observations in IPF could be transferable to intestinal fibrosis and that PFD inhibits the proliferation and extracellular matrix (ECM) turnover of gut-derived fibroblasts from CD patients. Fibroblasts were isolated from biopsies of inflamed (n = 8) and non-inflamed (n = 5) colonic mucosa. Expression of CD90 and alpha-smooth muscle actin (αSMA) expression was determined by flow cytometry. The fibroblasts were cultured with PFD (0.5, 1.0 and 2.0 mg/ml). Proliferation was evaluated with CellTiter 96(®) AQueous One Solution Cell Proliferation Assay. Production of matrix metalloproteinase-3 (MMP-3), tissue inhibitor of metalloproteinases-1 (TIMP-1) and collagen were assessed using ELISA and calorimetric assays, respectively. The majority of the fibroblasts were αSMA-positive myofibroblasts. PFD inhibited fibroblast proliferation [0.94 (PFD 0.5 mg/ml); 0.76 (1.0 mg/ml); 0.58 (2.0 mg/ml)] and production of MMP-3 [0.85 (0.5 mg/ml); 0.74 (1.0 mg/ml); 0.63 (2.0 mg/ml)] dose-dependently (both p = 0.0001). The anti-proliferative effect of PFD was reversible (p = 0.0001), indicating that PFD does not act by an irreversible cytotoxic mechanism. PFD did not influence neither TIMP-1 nor collagen production. PFD inhibited the proliferation and the production of MMP-3 dose-dependently in gut-derived fibroblast from CD patients. Our observations support further studies on PFD in stricturing CD.

  3. Transcriptional activation of peroxisome proliferator-activated receptor-γ requires activation of both protein kinase A and Akt during adipocyte differentiation

    International Nuclear Information System (INIS)

    Kim, Sang-pil; Ha, Jung Min; Yun, Sung Ji; Kim, Eun Kyoung; Chung, Sung Woon; Hong, Ki Whan; Kim, Chi Dae; Bae, Sun Sik

    2010-01-01

    Research highlights: → Elevated cAMP activates both PKA and Epac. → PKA activates CREB transcriptional factor and Epac activates PI3K/Akt pathway via Rap1. → Akt modulates PPAR-γ transcriptional activity in concert with CREB. -- Abstract: Peroxisome proliferator-activated receptor-γ (PPAR-γ) is required for the conversion of pre-adipocytes. However, the mechanism underlying activation of PPAR-γ is unclear. Here we showed that cAMP-induced activation of protein kinase A (PKA) and Akt is essential for the transcriptional activation of PPAR-γ. Hormonal induction of adipogenesis was blocked by a phosphatidylinositol 3-kinase (PI3K) inhibitor (LY294002), by a protein kinase A (PKA) inhibitor (H89), and by a Rap1 inhibitor (GGTI-298). Transcriptional activity of PPAR-γ was markedly enhanced by 3-isobutyl-1-methylxanthine (IBMX), but not insulin and dexamethasone. In addition, IBMX-induced PPAR-γ transcriptional activity was blocked by PI3K/Akt, PKA, or Rap1 inhibitors. 8-(4-Chlorophenylthio)-2'-O-methyl-cAMP (8-pCPT-2'-O-Me-cAMP) which is a specific agonist for exchanger protein directly activated by cAMP (Epac) significantly induced the activation of Akt. Furthermore, knock-down of Akt1 markedly attenuated PPAR-γ transcriptional activity. These results indicate that both PKA and Akt signaling pathways are required for transcriptional activation of PPAR-γ, suggesting post-translational activation of PPAR-γ might be critical step for adipogenic gene expression.

  4. Phagocytic response of astrocytes to damaged neighboring cells.

    Directory of Open Access Journals (Sweden)

    Nicole M Wakida

    Full Text Available This study aims to understand the phagocytic response of astrocytes to the injury of neurons or other astrocytes at the single cell level. Laser nanosurgery was used to damage individual cells in both primary mouse cortical astrocytes and an established astrocyte cell line. In both cases, the release of material/substances from laser-irradiated astrocytes or neurons induced a phagocytic response in near-by astrocytes. Propidium iodide stained DNA originating from irradiated cells was visible in vesicles of neighboring cells, confirming phagocytosis of material from damaged cortical cells. In the presence of an intracellular pH indicator dye, newly formed vesicles correspond to acidic pH fluorescence, thus suggesting lysosome bound degradation of cellular debris. Cells with shared membrane connections prior to laser damage had a significantly higher frequency of induced phagocytosis compared to isolated cells with no shared membrane. The increase in phagocytic response of cells with a shared membrane occurred regardless of the extent of shared membrane (a thin filopodial connection vs. a cell cluster with significant shared membrane. In addition to the presence (or lack of a membrane connection, variation in phagocytic ability was also observed with differences in injury location within the cell and distance separating isolated astrocytes. These results demonstrate the ability of an astrocyte to respond to the damage of a single cell, be it another astrocyte, or a neuron. This single-cell level of analysis results in a better understanding of the role of astrocytes to maintain homeostasis in the CNS, particularly in the sensing and removal of debris in damaged or pathologic nervous tissue.

  5. Pituitary adenylyl cyclase activating polypeptide inhibits gli1 gene expression and proliferation in primary medulloblastoma derived tumorsphere cultures

    Directory of Open Access Journals (Sweden)

    Dong Hongmei

    2010-12-01

    Full Text Available Abstract Background Hedgehog (HH signaling is critical for the expansion of granule neuron precursors (GNPs within the external granular layer (EGL during cerebellar development. Aberrant HH signaling within GNPs is thought to give rise to medulloblastoma (MB - the most commonly-observed form of malignant pediatric brain tumor. Evidence in both invertebrates and vertebrates indicates that cyclic AMP-dependent protein kinase A (PKA antagonizes HH signalling. Receptors specific for the neuropeptide pituitary adenylyl cyclase activating polypeptide (PACAP, gene name ADCYAP1 are expressed in GNPs. PACAP has been shown to protect GNPs from apoptosis in vitro, and to interact with HH signaling to regulate GNP proliferation. PACAP/ptch1 double mutant mice exhibit an increased incidence of MB compared to ptch1 mice, indicating that PACAP may regulate HH pathway-mediated MB pathogenesis. Methods Primary MB tumorsphere cultures were prepared from thirteen ptch1+/-/p53+/- double mutant mice and treated with the smoothened (SMO agonist purmorphamine, the SMO antagonist SANT-1, the neuropeptide PACAP, the PKA activator forskolin, and the PKA inhibitor H89. Gene expression of gli1 and [3H]-thymidine incorporation were assessed to determine drug effects on HH pathway activity and proliferation, respectively. PKA activity was determined in cell extracts by Western blotting using a phospho-PKA substrate antibody. Results Primary tumor cells cultured for 1-week under serum-free conditions grew as tumorspheres and were found to express PAC1 receptor transcripts. Gli1 gene expression was significantly reduced by SANT-1, PACAP and forskolin, but was unaffected by purmorphamine. The attenuation of gli1 gene expression by PACAP was reversed by the PKA inhibitor H89, which also blocked PKA activation. Treatment of tumorsphere cultures with PACAP, forskolin, and SANT-1 for 24 or 48 hours reduced proliferation. Conclusions Primary tumorspheres derived from ptch1+/-/p53

  6. Pituitary adenylyl cyclase activating polypeptide inhibits gli1 gene expression and proliferation in primary medulloblastoma derived tumorsphere cultures

    International Nuclear Information System (INIS)

    Cohen, Joseph R; Resnick, Daniel Z; Niewiadomski, Pawel; Dong, Hongmei; Liau, Linda M; Waschek, James A

    2010-01-01

    Hedgehog (HH) signaling is critical for the expansion of granule neuron precursors (GNPs) within the external granular layer (EGL) during cerebellar development. Aberrant HH signaling within GNPs is thought to give rise to medulloblastoma (MB) - the most commonly-observed form of malignant pediatric brain tumor. Evidence in both invertebrates and vertebrates indicates that cyclic AMP-dependent protein kinase A (PKA) antagonizes HH signalling. Receptors specific for the neuropeptide pituitary adenylyl cyclase activating polypeptide (PACAP, gene name ADCYAP1) are expressed in GNPs. PACAP has been shown to protect GNPs from apoptosis in vitro, and to interact with HH signaling to regulate GNP proliferation. PACAP/ptch1 double mutant mice exhibit an increased incidence of MB compared to ptch1 mice, indicating that PACAP may regulate HH pathway-mediated MB pathogenesis. Primary MB tumorsphere cultures were prepared from thirteen ptch1 +/- /p53 +/- double mutant mice and treated with the smoothened (SMO) agonist purmorphamine, the SMO antagonist SANT-1, the neuropeptide PACAP, the PKA activator forskolin, and the PKA inhibitor H89. Gene expression of gli1 and [ 3 H]-thymidine incorporation were assessed to determine drug effects on HH pathway activity and proliferation, respectively. PKA activity was determined in cell extracts by Western blotting using a phospho-PKA substrate antibody. Primary tumor cells cultured for 1-week under serum-free conditions grew as tumorspheres and were found to express PAC1 receptor transcripts. Gli1 gene expression was significantly reduced by SANT-1, PACAP and forskolin, but was unaffected by purmorphamine. The attenuation of gli1 gene expression by PACAP was reversed by the PKA inhibitor H89, which also blocked PKA activation. Treatment of tumorsphere cultures with PACAP, forskolin, and SANT-1 for 24 or 48 hours reduced proliferation. Primary tumorspheres derived from ptch1 +/- /p53 +/- mice exhibit constitutive HH pathway activity

  7. Fungal invasion of normally non-phagocytic host cells.

    Directory of Open Access Journals (Sweden)

    Scott G Filler

    2006-12-01

    Full Text Available Many fungi that cause invasive disease invade host epithelial cells during mucosal and respiratory infection, and subsequently invade endothelial cells during hematogenous infection. Most fungi invade these normally non-phagocytic host cells by inducing their own uptake. Candida albicans hyphae interact with endothelial cells in vitro by binding to N-cadherin on the endothelial cell surface. This binding induces rearrangement of endothelial cell microfilaments, which results in the endocytosis of the organism. The capsule of Cryptococcus neoformans is composed of glucuronoxylomannan, which binds specifically to brain endothelial cells, and appears to mediate both adherence and induction of endocytosis. The mechanisms by which other fungal pathogens induce their own uptake are largely unknown. Some angioinvasive fungi, such as Aspergillus species and the Zygomycetes, invade endothelial cells from the abluminal surface during the initiation of invasive disease, and subsequently invade the luminal surface of endothelial cells during hematogenous dissemination. Invasion of normally non-phagocytic host cells has different consequences, depending on the type of invading fungus. Aspergillus fumigatus blocks apoptosis of pulmonary epithelial cells, whereas Paracoccidioides brasiliensis induces apoptosis of epithelial cells. This review summarizes the mechanisms by which diverse fungal pathogens invade normally non-phagocytic host cells and discusses gaps in our knowledge that provide opportunities for future research.

  8. Role of the phagocytes on embryos: some morphological aspects.

    Science.gov (United States)

    Da Silva, José Roberto Machado Cunha

    2002-06-15

    Phagocytosis in embryos was studied by Elie Metchnikoff more than a century ago and is a pillar of the Phagocytic Theory. Throughout the last three decades phagocytosis in embryos has been studied from different perspectives, which this review describes and analyzes. The following branches were identified: 1) the search for the origin and first identification of well-known adult phagocytes in embryos, including their role after induced injuries; 2) the search for the occurrence of phagocytosis in embryos and its role during their physiological development; and 3) the search for phagocytosis in embryos, as a tool to study identity and self-recognition. It is possible to verify that different cell types are able to undertake phagocytosis, under a variety of different stimuli, and that the nature of what is phagocytosed also varies widely. Although the overwhelming majority of species described among metazoarians are invertebrates, most published articles in this field relate to mammals (particularly mice and humans) and birds (particularly chicks). In order to enrich this field of knowledge, research using a wider variety of vertebrate and invertebrate species should be undertaken. Furthermore, the present knowledge of phagocytosis in embryos needs a revised paradigm capable of embracing all the above-mentioned research trends under a single, more general, biological theory. In this sense, Metchnikoff's Phagocytic Theory, which is based on a broad biological paradigm and is thus capable of dealing with all research trends mentioned herein, should be revisited in order to contribute to this edification. Copyright 2002 Wiley-Liss, Inc.

  9. Selective Biological Responses of Phagocytes and Lungs to Purified Histones.

    Science.gov (United States)

    Fattahi, Fatemeh; Grailer, Jamison J; Lu, Hope; Dick, Rachel S; Parlett, Michella; Zetoune, Firas S; Nuñez, Gabriel; Ward, Peter A

    2017-01-01

    Histones invoke strong proinflammatory responses in many different organs and cells. We assessed biological responses to purified or recombinant histones, using human and murine phagocytes and mouse lungs. H1 had the strongest ability in vitro to induce cell swelling independent of requirements for toll-like receptors (TLRs) 2 or 4. These responses were also associated with lactate dehydrogenase release. H3 and H2B were the strongest inducers of [Ca2+]i elevations in phagocytes. Cytokine and chemokine release from mouse and human phagocytes was predominately a function of H2A and H2B. Double TLR2 and TLR4 knockout (KO) mice had dramatically reduced cytokine release induced in macrophages exposed to individual histones. In contrast, macrophages from single TLR-KO mice showed few inhibitory effects on cytokine production. Using the NLRP3 inflammasome protocol, release of mature IL-1β was predominantly a feature of H1. Acute lung injury following the airway delivery of histones suggested that H1, H2A, and H2B were linked to alveolar leak of albumin and the buildup of polymorphonuclear neutrophils as well as the release of chemokines and cytokines into bronchoalveolar fluids. These results demonstrate distinct biological roles for individual histones in the context of inflammation biology and the requirement of both TLR2 and TLR4. © 2017 S. Karger AG, Basel.

  10. Profile of cell proliferation and apoptosis activated by the intrinsic and extrinsic pathways in the prostate of aging rats.

    Science.gov (United States)

    Gonzaga, Amanda C R; Campolina-Silva, Gabriel H; Werneck-Gomes, Hipácia; Moura-Cordeiro, Júnia D; Santos, Letícia C; Mahecha, Germán A B; Morais-Santos, Mônica; Oliveira, Cleida A

    2017-06-01

    Estrogens acting through the receptors ERα and ERβ participate in prostate normal growth and cancer. ERβ is highly expressed in the prostate epithelium, playing pro-apoptotic, anti-proliferative, and pro-differentiation roles. Apoptosis is activated by the intrinsic pathway after castration and by the extrinsic pathway after ERβ agonist treatment. This differential activation of apoptotic pathways is important since a major problem in the treatment of prostate cancer is the recurrence of tumors after androgen withdrawal. However, a comprehensive study about the pattern of apoptosis in the aging prostate is lacking, a knowledge gap that we aimed to address herein. Cellular age-related proliferative and apoptotic profiles of prostate tissue obtained from aging Wistar rats were evaluated. Cell death (caspase-3, -8, -9, TNFα) was assessed by immunohistochemistry, immunofluorescence, and TUNEL. Cell proliferation (MCM7) and cell survival factors (ERK1/2, p-ERK1/2, p-Akt, and NF-κB) were determined by immunohistochemistry. As the rats aged, the number of proliferating cells gradually reduced in the normal epithelium of all prostate lobes, while increasing in focal areas of intraepithelial proliferation. Interestingly, in areas of intraepithelial proliferation, we observed a reduction in the number of cells positive for caspase-3, -8, and -9. Regardless the animal's age, few prostate epithelial cells were positive for caspase-3, caspase-9, and TUNEL. In contrast, a progressive increase was seen in the positivity for caspase-8, especially in the atrophic epithelium of ventral prostate, which coincided with a reduction in TNFα immunoreaction. However, morphology of most caspase-8 positive cells suggests that they were not apoptotic. We also found reduced ERβ expression in the same areas. Possibly, low levels of the pro-apoptotic inductors TNFα and ERβ direct caspase-8 activity to an alternative pro-survival role in the atrophic epithelium. This hypothesis is

  11. Peroxisome proliferator-activated receptor α agonist-induced down-regulation of hepatic glucocorticoid receptor expression in SD rats

    International Nuclear Information System (INIS)

    Chen Xiang; Li Ming; Sun Weiping; Bi Yan; Cai Mengyin; Liang Hua; Yu Qiuqiong; He Xiaoying; Weng Jianping

    2008-01-01

    It was reported that glucocorticoid production was inhibited by fenofibrate through suppression of type-1 11β-hydroxysteroid dehydrogenase gene expression in liver. The inhibition might be a negative-feedback regulation of glucocorticoid receptor (GR) activity by peroxisome proliferator-activated receptor alpha (PPARα), which is quickly induced by glucocorticoid in the liver. However, it is not clear if GR expression is changed by fenofibrate-induced PPARα activation. In this study, we tested this possibility in the liver of Sprague-Dawley rats. GR expression was reduced by fenofibrate in a time- and does-dependent manner. The inhibition was observed in liver, but not in fat and muscle. The corticosterone level in the blood was increased significantly by fenofibrate. These effects of fenofibrate were abolished by PPARα inhibitor MK886, suggesting that fenofibrate activated through PPARα. In conclusion, inhibition of GR expression may represent a new molecular mechanism for the negative feedback regulation of GR activity by PPARα

  12. Interleukin-1β regulates cell proliferation and activity of extracellular matrix remodelling enzymes in cultured primary pig heart cells

    International Nuclear Information System (INIS)

    Zitta, Karina; Brandt, Berenice; Wuensch, Annegret; Meybohm, Patrick; Bein, Berthold; Steinfath, Markus; Scholz, Jens; Albrecht, Martin

    2010-01-01

    Research highlights: → Levels of IL-1β are increased in the pig myocardium after infarction. → Cultured pig heart cells possess IL-1 receptors. → IL-1β increases cell proliferation of pig heart cells in-vitro. → IL-1β increases MMP-2 and MMP-9 activity in pig heart cells in-vitro. → IL-1β may be important for tissue remodelling events after myocardial infarction. -- Abstract: After myocardial infarction, elevated levels of interleukins (ILs) are found within the myocardial tissue and IL-1β is considered to play a major role in tissue remodelling events throughout the body. In the study presented, we have established a cell culture model of primary pig heart cells to evaluate the effects of different concentrations of IL-1β on cell proliferation as well as expression and activity of enzymes typically involved in tissue remodelling. Primary pig heart cell cultures were derived from three different animals and stimulated with recombinant pig IL-1β. RNA expression was detected by RT-PCR, protein levels were evaluated by Western blotting, activity of matrix metalloproteinases (MMPs) was quantified by gelatine zymography and cell proliferation was measured using colorimetric MTS assays. Pig heart cells express receptors for IL-1 and application of IL-1β resulted in a dose-dependent increase of cell proliferation (P < 0.05 vs. control; 100 ng/ml; 24 h). Gene expression of caspase-3 was increased by IL-1β (P < 0.05 vs. control; 100 ng/ml; 3 h), and pro-caspase-3 but not active caspase was detected in lysates of pig heart cells by Western blotting. MMP-2 gene expression as well as enzymatic activities of MMP-2 and MMP-9 were increased by IL-1β (P < 0.05 vs. control; 100 ng/ml; 3 h for gene expression, 48 and 72 h for enzymatic activities of MMP-2 and MMP-9, respectively). Our in vitro data suggest that IL-1β plays a major role in the events of tissue remodelling in the heart. Combined with our recently published in vivo data (Meybohm et al., PLoS One

  13. Interleukin-1{beta} regulates cell proliferation and activity of extracellular matrix remodelling enzymes in cultured primary pig heart cells

    Energy Technology Data Exchange (ETDEWEB)

    Zitta, Karina; Brandt, Berenice [Department of Anesthesiology and Intensive Care Medicine, University Hospital Schleswig-Holstein, Campus Kiel (Germany); Wuensch, Annegret [Institute of Molecular Animal Breeding and Biotechnology, Ludwig Maximilians University, Munich (Germany); Meybohm, Patrick; Bein, Berthold; Steinfath, Markus; Scholz, Jens [Department of Anesthesiology and Intensive Care Medicine, University Hospital Schleswig-Holstein, Campus Kiel (Germany); Albrecht, Martin, E-mail: Albrecht@anaesthesie.uni-kiel.de [Department of Anesthesiology and Intensive Care Medicine, University Hospital Schleswig-Holstein, Campus Kiel (Germany)

    2010-09-03

    Research highlights: {yields} Levels of IL-1{beta} are increased in the pig myocardium after infarction. {yields} Cultured pig heart cells possess IL-1 receptors. {yields} IL-1{beta} increases cell proliferation of pig heart cells in-vitro. {yields} IL-1{beta} increases MMP-2 and MMP-9 activity in pig heart cells in-vitro. {yields} IL-1{beta} may be important for tissue remodelling events after myocardial infarction. -- Abstract: After myocardial infarction, elevated levels of interleukins (ILs) are found within the myocardial tissue and IL-1{beta} is considered to play a major role in tissue remodelling events throughout the body. In the study presented, we have established a cell culture model of primary pig heart cells to evaluate the effects of different concentrations of IL-1{beta} on cell proliferation as well as expression and activity of enzymes typically involved in tissue remodelling. Primary pig heart cell cultures were derived from three different animals and stimulated with recombinant pig IL-1{beta}. RNA expression was detected by RT-PCR, protein levels were evaluated by Western blotting, activity of matrix metalloproteinases (MMPs) was quantified by gelatine zymography and cell proliferation was measured using colorimetric MTS assays. Pig heart cells express receptors for IL-1 and application of IL-1{beta} resulted in a dose-dependent increase of cell proliferation (P < 0.05 vs. control; 100 ng/ml; 24 h). Gene expression of caspase-3 was increased by IL-1{beta} (P < 0.05 vs. control; 100 ng/ml; 3 h), and pro-caspase-3 but not active caspase was detected in lysates of pig heart cells by Western blotting. MMP-2 gene expression as well as enzymatic activities of MMP-2 and MMP-9 were increased by IL-1{beta} (P < 0.05 vs. control; 100 ng/ml; 3 h for gene expression, 48 and 72 h for enzymatic activities of MMP-2 and MMP-9, respectively). Our in vitro data suggest that IL-1{beta} plays a major role in the events of tissue remodelling in the heart. Combined

  14. Hyaluronic acid enhances proliferation of human amniotic mesenchymal stem cells through activation of Wnt/β-catenin signaling pathway

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Ru-Ming; Sun, Ren-Gang; Zhang, Ling-Tao; Zhang, Qing-Fang; Chen, Dai-Xiong [Guizhou Center for Translational Medicine, Affiliated Hospital of Zunyi Medical University, 149 Dalian Road, Zunyi 563000 (China); Zhong, Jian-Jiang, E-mail: jjzhong@sjtu.edu.cn [State Key Laboratory of Microbial Metabolism, and School of Life Sciences & Biotechnology, Shanghai Jiao Tong University, Shanghai 200240 (China); Xiao, Jian-Hui, E-mail: jhxiao@yahoo.com [Guizhou Center for Translational Medicine, Affiliated Hospital of Zunyi Medical University, 149 Dalian Road, Zunyi 563000 (China)

    2016-07-15

    This study investigated the pro-proliferative effect of hyaluronic acid (HA) on human amniotic mesenchymal stem cells (hAMSCs) and the underlying mechanisms. Treatment with HA increased cell population growth in a dose- and time-dependent manner. Analyses by flow cytometry and immunocytochemistry revealed that HA did not change the cytophenotypes of hAMSCs. Additionally, the osteogenic, chondrogenic, and adipogenic differentiation capabilities of these hAMSCs were retained after HA treatment. Moreover, HA increased the mRNA expressions of wnt1, wnt3a, wnt8a, cyclin D1, Ki-67, and β-catenin as well as the protein level of β-catenin and cyclin D1 in hAMSCs; and the nuclear localization of β-catenin was also enhanced. Furthermore, the pro-proliferative effect of HA and up-regulated expression of Wnt/β-catenin pathway-associated proteins - wnt3a, β-catenin and cyclin D1 in hAMSCs were significantly inhibited upon pre-treatment with Wnt-C59, an inhibitor of the Wnt/β-catenin pathway. These results suggest that HA may positively regulate hAMSCs proliferation through regulation of the Wnt/β-catenin signaling pathway. - Highlights: • Hyaluronic acid (HA) could promote the proliferation of hAMSCs. • HA treatment dose not affect the pluripotency of hAMSCs. • HA increases hAMSCs proliferation through activation of Wnt/β-catenin signaling.

  15. Loss of p53 induces cell proliferation via Ras-independent activation of the Raf/Mek/Erk signaling pathway

    Science.gov (United States)

    Drosten, Matthias; Sum, Eleanor Y. M.; Lechuga, Carmen G.; Simón-Carrasco, Lucía; Jacob, Harrys K. C.; García-Medina, Raquel; Huang, Sidong; Beijersbergen, Roderick L.; Bernards, Rene; Barbacid, Mariano

    2014-01-01

    The Ras family of small GTPases constitutes a central node in the transmission of mitogenic stimuli to the cell cycle machinery. The ultimate receptor of these mitogenic signals is the retinoblastoma (Rb) family of pocket proteins, whose inactivation is a required step to license cell proliferation. However, little is known regarding the molecular events that connect Ras signaling with the cell cycle. Here, we provide genetic evidence to illustrate that the p53/p21 Cdk-interacting protein 1 (Cip1)/Rb axis is an essential component of the Ras signaling pathway. Indeed, knockdown of p53, p21Cip1, or Rb restores proliferative properties in cells arrested by ablation of the three Ras loci, H-, N- and K-Ras. Ras signaling selectively inactivates p53-mediated induction of p21Cip1 expression by inhibiting acetylation of specific lysine residues in the p53 DNA binding domain. Proliferation of cells lacking both Ras proteins and p53 can be prevented by reexpression of the human p53 ortholog, provided that it retains an active DNA binding domain and an intact lysine residue at position 164. These results unveil a previously unidentified role for p53 in preventing cell proliferation under unfavorable mitogenic conditions. Moreover, we provide evidence that cells lacking Ras and p53 proteins owe their proliferative properties to the unexpected retroactivation of the Raf/Mek/Erk cascade by a Ras-independent mechanism. PMID:25288756

  16. Total glucosides of paeony regulates JAK2/STAT3 activation and macrophage proliferation in diabetic rat kidneys.

    Science.gov (United States)

    Wang, Kun; Wu, Yong-Gui; Su, Jing; Zhang, Jing-Jing; Zhang, Pei; Qi, Xiang-Ming

    2012-01-01

    Total glucosides of paeony (TGP) is the major active constituent of Paeonia lactiflora Pall., which has shown renoprotection in experimental diabetic nephropathy. Activation of Janus kinase/signal transducers and activators of transcription (JAK/STAT) is an important mechanism by which hyperglycemia contributes to renal damage. Macrophages also play an essential role in the pathogenesis of diabetic nephropathy. Herein, we investigated the ability of TGP to modulate JAK2/STAT3 activation and macrophage proliferation in rats with streptozotocin (STZ)-induced diabetes. TGP (50, 100, and 200 mg/kg) was administered orally once a day for eight weeks. Levels of p-JAK2 and p-STAT3 were determined by Western blot analysis. Immunohistochemistry and double immunohistochemistry were used to identify p-STAT3, ED-1, PCNA/ED-1, and p-STAT3/ED-1-positive (+) cells. The elevated 24-h urinary albumin excretion rate was markedly attenuated by treatment with 50, 100, and 200 mg/kg TGP. Western blot analysis showed that the significantly increased levels of p-JAK2, p-STAT3 proteins in the kidneys of diabetic rats were significantly inhibited by 50, 100, and 200 mg/kg TGP treatment. The marked accumulation and proliferation of macrophages in diabetic kidneys were significantly inhibited by TGP treatment. ED-1+/p-STAT3+ cells were significantly increased in the kidneys from the model group but were significantly inhibited by TGP treatment. These results show that TGP significantly inhibited diabetic nephropathy progression and suggest that these protective effects are associated with the ability of TGP to inhibit the JAK2/STAT3 pathway and macrophage proliferation and action.

  17. T cell activation and proliferation following acute exercise in human subjects is altered by storage conditions and mitogen selection.

    Science.gov (United States)

    Siedlik, Jacob A; Deckert, Jake A; Benedict, Stephen H; Bhatta, Anuja; Dunbar, Amanda J; Vardiman, John P; Gallagher, Philip M

    2017-07-01

    Recent work investigating exercise induced changes in immunocompetence suggests that some of the ambiguity in the literature is resultant from different cell isolation protocols and mitogen selection. To understand this effect, we compared post-exercise measures of T cell activation and proliferation using two different stimulation methods (costimulation through CD28 or stimulation with phytohaemagglutinin [PHA]). Further, we investigated whether exercise induced changes are maintained when T cell isolation from whole blood is delayed overnight in either a room temperature or chilled (4°C) environment. As expected, an increased proliferation response was observed post-exercise in T cells isolated from whole blood of previously trained individuals immediately after blood collection. Also, cells stimulated with PHA after resting overnight in whole blood were not adversely impacted by the storage conditions. In contrast, allowing cells to rest overnight in whole blood prior to stimulation through CD28, lessened the proliferation observed by cells following exercise rendering both the room temperature and chilled samples closer to the results seen in the control condition. Changes in early markers of activation (CD25), followed a similar pattern, with activation in PHA stimulated cells remaining fairly robust after overnight storage; whereas cell activation following stimulation through CD3+CD28 was disproportionately decreased by the influence of overnight storage. These findings indicate that decisions regarding cell stimulation methods need to be paired with the timeline for T cell isolation from whole blood. These considerations will be especially important for field based studies of immunocompetence where there is a delay in getting whole blood samples to a lab for processing as well as clinical applications where a failure to isolate T cells in a timely manner may result in loss of the response of interest. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. Triptolide, a diterpenoid triepoxide, induces antitumor proliferation via activation of c-Jun NH2-terminal kinase 1 by decreasing phosphatidylinositol 3-kinase activity in human tumor cells

    International Nuclear Information System (INIS)

    Miyata, Yoshiki; Sato, Takashi; Ito, Akira

    2005-01-01

    Triptolide, a diterpenoid triepoxide extracted from the Chinese herb Tripterygium wilfordii Hook f., exerts antitumorigenic actions against several tumor cells, but the intracellular target signal molecule(s) for this antitumorigenesis activity of triptolide remains to be identified. In the present study, we demonstrated that triptolide, in a dose-dependent manner, inhibited the proliferation of human fibrosarcoma HT-1080, human squamous carcinoma SAS, and human uterine cervical carcinoma SKG-II cells. In addition, triptolide was found to decrease phosphatidylinositol 3-kinase (PI3K) activity. A PI3K inhibitor, LY-294002, mimicked the triptolide-induced antiproliferative activity in HT-1080, SAS, and SKG-II cells. There was no change in the activity of Akt or protein kinase C (PKC), both of which are downstream effectors in the PI3K pathway. Furthermore, the phosphorylation of Ras, Raf, and mitogen-activated protein/extracellular signal-regulated kinase 1/2 was not modified in HT-1080 cells treated with triptolide. However, the phosphorylation of c-Jun NH 2 -terminal kinase 1 (JNK1) was found to increase in both triptolide- and LY-294002-treated cells. Furthermore, the triptolide-induced inhibition of HT-1080 cell proliferation was not observed by JNK1 siRNA-treatment. These results provide novel evidence that PI3K is a crucial target molecule in the antitumorigenic action of triptolide. They further suggest a possible triptolide-induced inhibitory signal for tumor cell proliferation that is initiated by the decrease in PI3K activity, which in turn leads to the augmentation of JNK1 phosphorylation via the Akt and/or PKC-independent pathway(s). Moreover, it is likely that the activation of JNK1 is required for the triptolide-induced inhibition of tumor proliferation

  19. Plasticizers May Activate Human Hepatic Peroxisome Proliferator-Activated Receptor α Less Than That of a Mouse but May Activate Constitutive Androstane Receptor in Liver

    Science.gov (United States)

    Ito, Yuki; Nakamura, Toshiki; Yanagiba, Yukie; Ramdhan, Doni Hikmat; Yamagishi, Nozomi; Naito, Hisao; Kamijima, Michihiro; Gonzalez, Frank J.; Nakajima, Tamie

    2012-01-01

    Dibutylphthalate (DBP), di(2-ethylhexyl)phthalate (DEHP), and di(2-ethylhexyl)adipate (DEHA) are used as plasticizers. Their metabolites activate peroxisome proliferator-activated receptor (PPAR) α, which may be related to their toxicities. However, species differences in the receptor functions between rodents and human make it difficult to precisely extrapolate their toxicity from animal studies to human. In this paper, we compared the species differences in the activation of mouse and human hepatic PPARα by these plasticizers using wild-type (mPPARα) and humanized PPARα (hPPARα) mice. At 12 weeks old, each genotyped male mouse was classified into three groups, and fed daily for 2 weeks per os with corn oil (vehicle control), 2.5 or 5.0 mmol/kg DBP (696, 1392 mg/kg), DEHP (977, 1953 mg/kg), and DEHA (926, 1853 mg/kg), respectively. Generally, hepatic PPARα of mPPARα mice was more strongly activated than that of hPPARα mice when several target genes involving β-oxidation of fatty acids were evaluated. Interestingly, all plasticizers also activated hepatic constitutive androstane receptor (CAR) more in hPPARα mice than in mPPARα mice. Taken together, these plasticizers activated mouse and human hepatic PPARα as well as CAR. The activation of PPARα was stronger in mPPARα mice than in hPPARα mice, while the opposite was true of CAR. PMID:22792086

  20. Plasticizers May Activate Human Hepatic Peroxisome Proliferator-Activated Receptor α Less Than That of a Mouse but May Activate Constitutive Androstane Receptor in Liver

    Directory of Open Access Journals (Sweden)

    Yuki Ito

    2012-01-01

    Full Text Available Dibutylphthalate (DBP, di(2-ethylhexylphthalate (DEHP, and di(2-ethylhexyladipate (DEHA are used as plasticizers. Their metabolites activate peroxisome proliferator-activated receptor (PPAR α, which may be related to their toxicities. However, species differences in the receptor functions between rodents and human make it difficult to precisely extrapolate their toxicity from animal studies to human. In this paper, we compared the species differences in the activation of mouse and human hepatic PPARα by these plasticizers using wild-type (mPPARα and humanized PPARα (hPPARα mice. At 12 weeks old, each genotyped male mouse was classified into three groups, and fed daily for 2 weeks per os with corn oil (vehicle control, 2.5 or 5.0 mmol/kg DBP (696, 1392 mg/kg, DEHP (977, 1953 mg/kg, and DEHA (926, 1853 mg/kg, respectively. Generally, hepatic PPARα of mPPARα mice was more strongly activated than that of hPPARα mice when several target genes involving β-oxidation of fatty acids were evaluated. Interestingly, all plasticizers also activated hepatic constitutive androstane receptor (CAR more in hPPARα mice than in mPPARα mice. Taken together, these plasticizers activated mouse and human hepatic PPARα as well as CAR. The activation of PPARα was stronger in mPPARα mice than in hPPARα mice, while the opposite was true of CAR.

  1. [Formation of endogenous pyrogen by mononuclear phagocytes].

    Science.gov (United States)

    Agasarov, L G

    1980-03-01

    Incubation of alveolar macrophages of rabbits and peritoneal macrophages of the abdominal cavity washing of albino mice does not lead to endogenous pyrogen release. Peritoneal macrophages obtained after peritoneal administration to mice of thioglycollate, glycogen or heterologous blood cells do not discharge pyrogen either during incubation without additional stimulation. Macrophages isolated after intraperitoneal administration of heterologous blood cells do not exhibit pyrogenic activity possibly because of a long period of time elapsed after phagocytosis of foreign agents. The triggering of pyrogen formation by macrophages can be effected by means of in vitro phagocytosis of corpuscular particles: staphylococci or heterologous blood cells.

  2. Effects of protein kinase C activators and staurosporine on protein kinase activity, cell survival, and proliferation in Tetrahymena thermophila

    DEFF Research Database (Denmark)

    Straarup, EM; Schousboe, P; Hansen, HQ

    1997-01-01

    Autocrine factors prevent cell death in the ciliate Tetrahymena thermophila, a unicellular eukaryote, in a chemically defined medium. At certain growth conditions these factors are released at a sufficient concentration by > 500 cells ml-1 to support cell survival and proliferation. The protein...

  3. Activation of peroxisome proliferator-activated receptor gamma bypasses the function of the retinoblastoma protein in adipocyte differentiation

    DEFF Research Database (Denmark)

    Hansen, Jacob B.; Petersen, R K; Larsen, B M

    1999-01-01

    The retinoblastoma protein (pRB) is an important regulator of development, proliferation, and cellular differentiation. pRB was recently shown to play a pivotal role in adipocyte differentiation, to interact physically with adipogenic CCAAT/enhancer-binding proteins (C/EBPs), and to positively...

  4. NIK is involved in constitutive activation of the alternative NF-κB pathway and proliferation of pancreatic cancer cells

    International Nuclear Information System (INIS)

    Nishina, Takashi; Yamaguchi, Noritaka; Gohda, Jin; Semba, Kentaro; Inoue, Jun-ichiro

    2009-01-01

    Pancreatic cancer has one of the poorest prognoses among human neoplasms. Constitutive activation of NF-κB is frequently observed in pancreatic cancer cells and is involved in their malignancy. However, little is known about the molecular mechanism of this constitutive NF-κB activation. Here, we show that the alternative pathway is constitutively activated and NF-κB-inducing kinase (NIK), a mediator of the alternative pathway, is significantly expressed in pancreatic cancer cells. siRNA-mediated silencing of NIK expression followed by subcellular fractionation revealed that NIK is constitutively involved in the processing of p100 and nuclear transport of p52 and RelB in pancreatic cancer cells. In addition, NIK silencing significantly suppressed proliferation of pancreatic cancer cells. These results clearly indicate that NIK is involved in the constitutive activation of the alternative pathway and controls cell proliferation in pancreatic cancer cells. Therefore, NIK might be a novel target for the treatment of pancreatic cancer.

  5. In Vitro Antioxidant, Anticoagulant and Antimicrobial Activity and in Inhibition of Cancer Cell Proliferation by Xylan Extracted from Corn Cobs

    Science.gov (United States)

    Melo-Silveira, Raniere Fagundes; Fidelis, Gabriel Pereira; Costa, Mariana Santana Santos Pereira; Telles, Cinthia Beatrice Silva; Dantas-Santos, Nednaldo; de Oliveira Elias, Susana; Ribeiro, Vanessa Bley; Barth, Afonso Luis; Macedo, Alexandre José; Leite, Edda Lisboa; Rocha, Hugo Alexandre Oliveira

    2012-01-01

    Xylan is one of most abundant polymer after cellulose. However, its potential has yet to be completely recognized. Corn cobs contain a considerable reservoir of xylan. The aim of this work was to study some of the biological activities of xylan obtained from corn cobs after alkaline extraction enhanced by ultrasonication. Physical chemistry and infrared analyses showed 130 kDa heteroxylan containing mainly xylose:arabinose: galactose:glucose (5.0:1.5:2.0:1.2). Xylan obtained exhibited total antioxidant activity corresponding to 48.5 mg of ascorbic acid equivalent/g of xylan. Furthermore, xylan displayed high ferric chelating activity (70%) at 2 mg/mL. Xylan also showed anticoagulant activity in aPTT test. In antimicrobial assay, the polysaccharide significantly inhibited bacterial growth of Klebsiella pneumoniae. In a test with normal and tumor human cells, after 72 h, only HeLa tumor cell proliferation was inhibited (p < 0.05) in a dose-dependent manner by xylan, reaching saturation at around 2 mg/mL, whereas 3T3 normal cell proliferation was not affected. The results suggest that it has potential clinical applications as antioxidant, anticoagulant, antimicrobial and antiproliferative compounds. PMID:22312261

  6. Sonic hedgehog stimulates the proliferation of rat gastric mucosal cells through ERK activation by elevating intracellular calcium concentration

    International Nuclear Information System (INIS)

    Osawa, Hiroyuki; Ohnishi, Hirohide; Takano, Koji; Noguti, Takasi; Mashima, Hirosato; Hoshino, Hiroko; Kita, Hiroto; Sato, Kiichi; Matsui, Hirofumi; Sugano, Kentaro

    2006-01-01

    Sonic Hedgehog (Shh), a member of hedgehog peptides family, is expressed in gastric gland epithelium. To elucidate Shh function to gastric mucosal cells, we examined the effect of Shh on the proliferation of a rat normal gastric mucosal cell line, RGM-1. RGM-1 cells express essential components of Shh receptor system, patched-1, and smoothened. Shh enhanced DNA synthesis in RGM-1 cells and elevated intracellular calcium concentration ([Ca 2+ ] i ). In addition, Shh as well as calcium ionophore A32187 rapidly activated ERK. However, Shh failed to activate ERK under calcium-free culture condition. Pretreatment of cells with PD98059 attenuated the DNA synthesis promoted by Shh. Moreover, when cells were pretreated with cyclopamine, Shh could not elevate [Ca 2+ ] i , activate ERK or promote DNA synthesis. On the other hand, although Shh induced Gli-1 nuclear accumulation in RGM-1 cells, Shh activated ERK even in cells pretreated with actinomycin D. These results indicate that Shh promotes the proliferation of RGM-1 cells through an intracellular calcium- and ERK-dependent but transcription-independent pathway via Patched/Smoothened receptor system

  7. Tooth development in Ambystoma mexicanum: phosphatase activities, calcium accumulation and cell proliferation in the tooth-forming tissues.

    Science.gov (United States)

    Wistuba, Joachim; Ehmcke, Jens; Clemen, Günter

    2003-06-01

    Prerequisites of tooth formation, cell proliferation in the tooth-forming tissues, calcium accumulation and the enzymatic activities of alkaline (ALP) and acid phosphatases (ACP) were investigated by immunohistochemical and histochemical methods in various developmental stages of the Mexican Axolotl, Ambystoma mexicanum. During the growth of replacement teeth, the tooth-forming tissues continually recruit cells from the surrounding regions. The basal layer of the oral epithelium, the dental lamina and sometimes even the outer enamel epithelium provide cells for the differentiated inner enamel epithelium, in which the active ameloblasts are localized. The differentiating odontoblasts are derived from proliferating cells situated basally to the replacement teeth in the mesenchymal tissue. When differentiation has started and the cells have become functional, proliferative activity can no longer be observed. Calcium is accumulated close to the site of mineralization in the inner enamel epithelium and in the odontoblasts as it is in mammals, elasmobranchii and teleostei. The activities of ACP and ALP related to the mineralization of the replacement teeth are separated spatially and not sequentially as they are in mammals. However, the results indicate a similar function of these enzymatic components in relation to tooth formation and maturation of mineral deposition. Most of the substantial processes related to tooth formation reported from other vertebrates occur in a manner similar to that in Ambystoma mexicanum, but there also seem to be basic mechanisms present that are realised in a unique way in this urodele.

  8. NIK is involved in constitutive activation of the alternative NF-{kappa}B pathway and proliferation of pancreatic cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Nishina, Takashi [Division of Cellular and Molecular Biology, Institute of Medical Science, University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-8639 (Japan); Yamaguchi, Noritaka [Division of Cellular and Molecular Biology, Institute of Medical Science, University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-8639 (Japan); Consolidated Research Institute for Advanced Science and Medical Care, Waseda University, 513 Wasedatsurumaki-cho, Shinjuku-ku, Tokyo 162-0041 (Japan); Gohda, Jin [Division of Cellular and Molecular Biology, Institute of Medical Science, University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-8639 (Japan); Semba, Kentaro [Consolidated Research Institute for Advanced Science and Medical Care, Waseda University, 513 Wasedatsurumaki-cho, Shinjuku-ku, Tokyo 162-0041 (Japan); Department of Life Science and Medical Bio-science, Waseda University, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480 (Japan); Inoue, Jun-ichiro, E-mail: jun-i@ims.u-tokyo.ac.jp [Division of Cellular and Molecular Biology, Institute of Medical Science, University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-8639 (Japan)

    2009-10-09

    Pancreatic cancer has one of the poorest prognoses among human neoplasms. Constitutive activation of NF-{kappa}B is frequently observed in pancreatic cancer cells and is involved in their malignancy. However, little is known about the molecular mechanism of this constitutive NF-{kappa}B activation. Here, we show that the alternative pathway is constitutively activated and NF-{kappa}B-inducing kinase (NIK), a mediator of the alternative pathway, is significantly expressed in pancreatic cancer cells. siRNA-mediated silencing of NIK expression followed by subcellular fractionation revealed that NIK is constitutively involved in the processing of p100 and nuclear transport of p52 and RelB in pancreatic cancer cells. In addition, NIK silencing significantly suppressed proliferation of pancreatic cancer cells. These results clearly indicate that NIK is involved in the constitutive activation of the alternative pathway and controls cell proliferation in pancreatic cancer cells. Therefore, NIK might be a novel target for the treatment of pancreatic cancer.

  9. The orphan nuclear receptor LRH-1 and ERα activate GREB1 expression to induce breast cancer cell proliferation.

    Directory of Open Access Journals (Sweden)

    Ashwini L Chand

    Full Text Available BACKGROUND: Liver Receptor Homolog 1 (LRH-1, NR5A2 is an orphan nuclear receptor that is over-expressed in cancers in tissues such as the breast, colon and pancreas. LRH-1 plays important roles in embryonic development, steroidogenesis and cholesterol homeostasis. In tumor cells, LRH-1 induces proliferation and cell cycle progression. High LRH-1 expression is demonstrated in breast cancers, positively correlating with ERα status and aromatase activity. LRH-1 dependent cellular mechanisms in breast cancer epithelial cells are poorly defined. Hence in the present study we investigated the actions of LRH-1 in estrogen receptor α (ERα positive breast cancer cells. RESULTS: The study aimed to investigate LRH-1 dependent mechanisms that promote breast cancer proliferation. We identified that LRH-1 regulated the expression of Growth Regulation by Estrogen in Breast Cancer 1 (GREB1 in MCF-7 and MDA-MB-231 cells. Over-expression of LRH-1 increased GREB1 mRNA levels while knockdown of LRH-1 reduced its expression. GREB1 is a well characterised ERα target gene, with three estrogen response elements (ERE located on its promoter. Chromatin immunoprecipitation studies provided evidence of the co-localisation of LRH-1 and ERα at all three EREs. With electrophoretic mobility shift assays, we demonstrated direct binding of LRH-1 to EREs located on GREB1 and Trefoil Factor 1 (TFF1, pS2 promoters. LRH-1 and ERα co-operatively activated transcription of ERE luciferase reporter constructs suggesting an overlap in regulation of target genes in breast cancer cells. Over-expression of LRH-1 resulted in an increase in cell proliferation. This effect was more pronounced with estradiol treatment. In the presence of ICI 182,780, an ERα antagonist, LRH-1 still induced proliferation. CONCLUSIONS: We conclude that in ER-positive breast cancer cells, LRH-1 promotes cell proliferation by enhancing ERα mediated transcription of target genes such as GREB-1. Collectively

  10. Human TMEM174 that is highly expressed in kidney tissue activates AP-1 and promotes cell proliferation

    International Nuclear Information System (INIS)

    Wang, Pingzhang; Sun, Bo; Hao, Dongxia; Zhang, Xiujun; Shi, Taiping; Ma, Dalong

    2010-01-01

    Mitogen-activated protein kinase (MAPK) cascades play an important role in regulation of AP-1 activity through the phosphorylation of distinct substrates. In the present study, we identified a novel protein, TMEM174, whose RNA transcripts are highly expressed in human kidney tissue. TMEM174 is comprised of 243 amino acids, and contains two predicted transmembrane helices which determine its subcellular localization in endoplasmic reticulum and influences its functions. Over-expression of TMME174 enhanced the transcriptional activity of AP-1 and promoted cell proliferation, whereas the truncated mutant TMEM174ΔTM without the transmembrane regions did not retain these functions. The possible mechanism of activation of AP-1 by TMEM174 was further examined. Our results suggest the potential role of TMEM174 in renal development and physiological function.

  11. Human TMEM174 that is highly expressed in kidney tissue activates AP-1 and promotes cell proliferation

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Pingzhang [Chinese National Human Genome Center, 3-707 North YongChang Road BDA, Beijing 100191 (China); Laboratory of Medical Immunology, School of Basic Medical Science, Peking University Health Science Center, No. 38 Xueyuan Road, Beijing 100191 (China); Peking University Center for Human Disease Genomics, No. 38 Xueyuan Road, Beijing 100191 (China); Sun, Bo; Hao, Dongxia [Department of Biology, Northchina Coal Medical College, No. 57 JianShe South Road, Tangshan 063000 (China); Zhang, Xiujun, E-mail: zhangxiujun66@yahoo.com.cn [Department of Biology, Northchina Coal Medical College, No. 57 JianShe South Road, Tangshan 063000 (China); Shi, Taiping, E-mail: taiping_shi@yahoo.com.cn [Chinese National Human Genome Center, 3-707 North YongChang Road BDA, Beijing 100191 (China); Laboratory of Medical Immunology, School of Basic Medical Science, Peking University Health Science Center, No. 38 Xueyuan Road, Beijing 100191 (China); Peking University Center for Human Disease Genomics, No. 38 Xueyuan Road, Beijing 100191 (China); Ma, Dalong [Chinese National Human Genome Center, 3-707 North YongChang Road BDA, Beijing 100191 (China); Laboratory of Medical Immunology, School of Basic Medical Science, Peking University Health Science Center, No. 38 Xueyuan Road, Beijing 100191 (China); Peking University Center for Human Disease Genomics, No. 38 Xueyuan Road, Beijing 100191 (China)

    2010-04-16

    Mitogen-activated protein kinase (MAPK) cascades play an important role in regulation of AP-1 activity through the phosphorylation of distinct substrates. In the present study, we identified a novel protein, TMEM174, whose RNA transcripts are highly expressed in human kidney tissue. TMEM174 is comprised of 243 amino acids, and contains two predicted transmembrane helices which determine its subcellular localization in endoplasmic reticulum and influences its functions. Over-expression of TMME174 enhanced the transcriptional activity of AP-1 and promoted cell proliferation, whereas the truncated mutant TMEM174{Delta}TM without the transmembrane regions did not retain these functions. The possible mechanism of activation of AP-1 by TMEM174 was further examined. Our results suggest the potential role of TMEM174 in renal development and physiological function.

  12. VEGF-A/NRP1 stimulates GIPC1 and Syx complex formation to promote RhoA activation and proliferation in skin cancer cells

    Directory of Open Access Journals (Sweden)

    Ayumi Yoshida

    2015-09-01

    Full Text Available Neuropilin-1 (NRP1 has been identified as a VEGF-A receptor. DJM-1, a human skin cancer cell line, expresses endogenous VEGF-A and NRP1. In the present study, the RNA interference of VEGF-A or NRP1 suppressed DJM-1 cell proliferation. Furthermore, the overexpression of the NRP1 wild type restored shNRP1-treated DJM-1 cell proliferation, whereas NRP1 cytoplasmic deletion mutants did not. A co-immunoprecipitation analysis revealed that VEGF-A induced interactions between NRP1 and GIPC1, a scaffold protein, and complex formation between GIPC1 and Syx, a RhoGEF. The knockdown of GIPC1 or Syx reduced active RhoA and DJM-1 cell proliferation without affecting the MAPK or Akt pathway. C3 exoenzyme or Y27632 inhibited the VEGF-A-induced proliferation of DJM-1 cells. Conversely, the overexpression of the constitutively active form of RhoA restored the proliferation of siVEGF-A-treated DJM-1 cells. Furthermore, the inhibition of VEGF-A/NRP1 signaling upregulated p27, a CDK inhibitor. A cell-penetrating oligopeptide that targeted GIPC1/Syx complex formation inhibited the VEGF-A-induced activation of RhoA and suppressed DJM-1 cell proliferation. In conclusion, this new signaling pathway of VEGF-A/NRP1 induced cancer cell proliferation by forming a GIPC1/Syx complex that activated RhoA to degrade the p27 protein.

  13. Panax ginseng total protein promotes proliferation and secretion of collagen in NIH/3T3 cells by activating extracellular signal-related kinase pathway

    Directory of Open Access Journals (Sweden)

    Xuenan Chen

    2017-07-01

    Conclusion: Our studies suggest that GTP promoted proliferation and secretion of collagen in NIH/3T3 cells by activating the ERK signal pathway, which shed light on a potential function of GTP in promoting wound healing.

  14. Variation in the peroxisome proliferator-activated receptor δ gene in relation to common metabolic traits in 7,495 middle-aged white people

    DEFF Research Database (Denmark)

    Grarup, Niels; Albrechtsen, A.; Ek, J.

    2007-01-01

    Studies in animals reveal that peroxisome proliferator-activated receptor delta (PPARdelta) regulates glucose metabolism and insulin sensitivity in both the liver and skeletal muscles. Moreover, PPARdelta augments physical endurance and increases oxidative metabolism, thereby averting obesity. Th...

  15. Study on the proliferation of human gastric cancer cell AGS by activation of EGFR in H2O2.

    Science.gov (United States)

    Wang, Q; Shen, W; Tao, G-Q; Sun, J; Shi, L-P

    2017-03-01

    This study is to investigate the effect of low concentration hydrogen peroxide (H2O2) on the proliferation of gastric cancer AGS cell line in vitro and the mechanism. AGS cells were treated with different low concentrations of H2O2 (1, 0.1, 0.01, and 0.001 μm) for 48 hours. The effect of H2O2 concentration gradient on the activity of AGS cell activities was detected by methyl thiazolyl tetrazolium (MTT) method. The expression of the epidermal growth factor receptor (EGFR) and its downstream signaling pathway extracellular signal-regulated kinase (ERK) protein in H2O2 was detected by Western blot method; moreover, the effect of H2O2 on intracellular reactive oxygen species (ROS) in AGS cells was observed under the fluorescence microscope and quantitative analysis by flow cytometry. The effect of H2O2 on the level of c-myc mRNA in AGS cells was also detected by reverse transcription polymerase chain reaction (RT-PCR). MTT detection results showed that 1 μm and 0.1 μm H2O2 at 48h can effectively promote the proliferation of AGS cells (pH2O2 treatment of AGS cells, the EGFR protein levels and ERK protein phosphorylation levels increased significantly (pH2O2 increased the intracellular reactive oxygen species (ROS). RT-PCR results showed the levels of c-myc mRNA in AGS cells treated with a low concentration of H2O2 were significantly increased (pH2O2 can significantly promote the proliferation of AGS cells by activating EGFR/ERK signaling pathway.

  16. Peroxisome proliferator-activated receptor α ligands and modulators from dietary compounds: Types, screening methods and functions.

    Science.gov (United States)

    Yang, Haixia; Xiao, Lei; Wang, Nanping

    2017-04-01

    Peroxisome proliferator-activated receptor α (PPARα) plays a key role in lipid metabolism and glucose homeostasis and a crucial role in the prevention and treatment of metabolic diseases. Natural dietary compounds, including nutrients and phytochemicals, are PPARα ligands or modulators. High-throughput screening assays have been developed to screen for PPARα ligands and modulators in our diet. In the present review, we discuss recent advances in our knowledge of PPARα, including its structure, function, and ligand and modulator screening assays, and summarize the different types of dietary PPARα ligands and modulators. © 2016 Ruijin Hospital, Shanghai Jiaotong University School of Medicine and John Wiley & Sons Australia, Ltd.

  17. Role of peroxisome proliferators-activated receptors in the pathogenesis and treatment of nonalcoholic fatty liver disease

    Institute of Scientific and Technical Information of China (English)

    Eric R Kallwitz; Alan McLachlan; Scott J Cotler

    2008-01-01

    Nonalcoholic fatty liver disease (NAFLD) is highly prevalent and can result in nonalcoholic steatohepatitis (NASH) and progressive liver disease including cirrhosis and hepatocellular carcinoma. A growing body of literature implicates the peroxisorne proliferators- activated receptors (PPARs) in the pathogenesis and treatment of NAFLD. These nuclear hormone receptors impact on hepatic triglyceride accumulation and insulin resistance. The aim of this review is to describe the data linking PPARα and PPARγ to NAFLD/NASH and to discuss the use of PPAR ligands for the treatment of NASH.

  18. Mutation analysis of peroxisome proliferator-activated receptor-gamma coactivator-1 (PGC-1) and relationships of identified amino acid polymorphisms to Type II diabetes mellitus

    DEFF Research Database (Denmark)

    Ek, J; Andersen, G; Urhammer, S A

    2001-01-01

    This study aimed to investigate if variability in the peroxisome proliferator-activated receptor-gamma coactivator-1 (PGC-1) gene is associated with Type II (non-insulin-dependent) diabetes mellitus.......This study aimed to investigate if variability in the peroxisome proliferator-activated receptor-gamma coactivator-1 (PGC-1) gene is associated with Type II (non-insulin-dependent) diabetes mellitus....

  19. New Insights into the Immunobiology of Mononuclear Phagocytic Cells and Their Relevance to the Pathogenesis of Cardiovascular Diseases

    Directory of Open Access Journals (Sweden)

    Liliana Maria Sanmarco

    2018-01-01

    Full Text Available Macrophages are the primary immune cells that reside within the myocardium, suggesting that these mononuclear phagocytes are essential in the orchestration of cardiac immunity and homeostasis. Independent of the nature of the injury, the heart triggers leukocyte activation and recruitment. However, inflammation is harmful to this vital terminally differentiated organ with extremely poor regenerative capacity. As such, cardiac tissue has evolved particular strategies to increase the stress tolerance and minimize the impact of inflammation. In this sense, growing evidences show that mononuclear phagocytic cells are particularly dynamic during cardiac inflammation or infection and would actively participate in tissue repair and functional recovery. They respond to soluble mediators such as metabolites or cytokines, which play central roles in the timing of the intrinsic cardiac stress response. During myocardial infarction two distinct phases of monocyte influx have been identified. Upon infarction, the heart modulates its chemokine expression profile that sequentially and actively recruits inflammatory monocytes, first, and healing monocytes, later. In the same way, a sudden switch from inflammatory macrophages (with microbicidal effectors toward anti-inflammatory macrophages occurs within the myocardium very shortly after infection with Trypanosoma cruzi, the causal agent of Chagas cardiomyopathy. While in sterile injury, healing response is necessary to stop tissue damage; during an intracellular infection, the anti-inflammatory milieu in infected hearts would promote microbial persistence. The balance of mononuclear phagocytic cells seems to be also dynamic in atherosclerosis influencing plaque initiation and fate. This review summarizes the participation of mononuclear phagocyte system in cardiovascular diseases, keeping in mind that the immune system evolved to promote the reestablishment of tissue homeostasis following infection/injury, and

  20. AJUBA LIM Proteins Limit Hippo Activity in Proliferating Cells by Sequestering the Hippo Core Kinase Complex in the Cytosol.

    Science.gov (United States)

    Jagannathan, Radhika; Schimizzi, Gregory V; Zhang, Kun; Loza, Andrew J; Yabuta, Norikazu; Nojima, Hitoshi; Longmore, Gregory D

    2016-10-15

    The Hippo pathway controls organ growth and is implicated in cancer development. Whether and how Hippo pathway activity is limited to sustain or initiate cell growth when needed is not understood. The members of the AJUBA family of LIM proteins are negative regulators of the Hippo pathway. In mammalian epithelial cells, we found that AJUBA LIM proteins limit Hippo regulation of YAP, in proliferating cells only, by sequestering a cytosolic Hippo kinase complex in which LATS kinase is inhibited. At the plasma membranes of growth-arrested cells, AJUBA LIM proteins do not inhibit or associate with the Hippo kinase complex. The ability of AJUBA LIM proteins to inhibit YAP regulation by Hippo and to associate with the kinase complex directly correlate with their capacity to limit Hippo signaling during Drosophila wing development. AJUBA LIM proteins did not influence YAP activity in response to cell-extrinsic or cell-intrinsic mechanical signals. Thus, AJUBA LIM proteins limit Hippo pathway activity in contexts where cell proliferation is needed. Copyright © 2016 Jagannathan et al.

  1. The Antifibrosis Effects of Peroxisome Proliferator-Activated Receptor δ on Rat Corneal Wound Healing after Excimer Laser Keratectomy

    Directory of Open Access Journals (Sweden)

    Yun Gu

    2014-01-01

    Full Text Available Corneal stromal fibrosis characterized by myofibroblasts and abnormal extracellular matrix (ECM is usually the result of inappropriate wound healing. The present study tested the hypothesis that the ligand activation of peroxisome proliferator-activated receptor (PPAR δ had antifibrosis effects in a rat model of corneal damage. Adult Sprague-Dawley rats underwent bilateral phototherapeutic keratectomy (PTK. The eyes were randomized into four groups: PBS, GW501516 (a selective agonist of PPARδ, GSK3787 (a selective antagonist of PPARδ, or GW501516 combined with GSK3787. The agents were subconjunctivally administered twice a week until sacrifice. The cellular aspects of corneal wound healing were evaluated with in vivo confocal imaging and postmortem histology. A myofibroblast marker (α-smooth muscle actin and ECM production (fibronectin, collagen type III and collagen type I were examined by immunohistochemistry and RT-PCR. At the early stages of wound healing, GW501516 inhibited reepithelialization and promoted angiogenesis. During the remodeling phase of wound healing, GW501516 attenuated the activation and proliferation of keratocytes, which could be reversed by GSK3787. GW501516 decreased transdifferentiation from keratocytes into myofibroblasts, ECM synthesis, and corneal haze. These results demonstrate that GW501516 controls corneal fibrosis and suggest that PPARδ may potentially serve as a therapeutic target for treating corneal scars.

  2. Immune Defenses of the Invasive Apple Snail Pomacea canaliculata (Caenogastropoda, Ampullariidae: Phagocytic Hemocytes in the Circulation and the Kidney.

    Directory of Open Access Journals (Sweden)

    Juan A Cueto

    Full Text Available Hemocytes in the circulation and kidney islets, as well as their phagocytic responses to microorganisms and fluorescent beads, have been studied in Pomacea canaliculata, using flow cytometry, light microscopy (including confocal laser scanning microscopy and transmission electron microscopy (TEM. Three circulating hemocyte types (hyalinocytes, agranulocytes and granulocytes were distinguished by phase contrast microscopy of living cells and after light and electron microscopy of fixed material. Also, three different populations of circulating hemocytes were separated by flow cytometry, which corresponded to the three hemocyte types. Hyalinocytes showed a low nucleus/cytoplasm ratio, and no apparent granules in stained material, but showed granules of moderate electron density under TEM (L granules and at least some L granules appear acidic when labeled with LysoTracker Red. Both phagocytic and non-phagocytic hyalinocytes lose most (if not all L granules when exposed to microorganisms in vitro. The phagosomes formed differed whether hyalinocytes were exposed to yeasts or to Gram positive or Gram negative bacteria. Agranulocytes showed a large nucleus/cytoplasm ratio and few or no granules. Granulocytes showed a low nucleus/cytoplasm ratio and numerous eosinophilic granules after staining. These granules are electron dense and rod-shaped under TEM (R granules. Granulocytes may show merging of R granules into gigantic ones, particularly when exposed to microorganisms. Fluorescent bead exposure of sorted hemocytes showed phagocytic activity in hyalinocytes, agranulocytes and granulocytes, but the phagocytic index was significantly higher in hyalinocytes. Extensive hemocyte aggregates ('islets' occupy most renal hemocoelic spaces and hyalinocyte-like cells are the most frequent component in them. Presumptive glycogen deposits were observed in most hyalinocytes in renal islets (they also occur in the circulation but less frequently and may mean that

  3. Activation of microglial cells triggers a release of brain-derived neurotrophic factor (BDNF) inducing their proliferation in an adenosine A2A receptor-dependent manner: A2A receptor blockade prevents BDNF release and proliferation of microglia

    Science.gov (United States)

    2013-01-01

    Background Brain-derived neurotrophic factor (BDNF) has been shown to control microglial responses in neuropathic pain. Since adenosine A2A receptors (A2ARs) control neuroinflammation, as well as the production and function of BDNF, we tested to see if A2AR controls the microglia-dependent secretion of BDNF and the proliferation of microglial cells, a crucial event in neuroinflammation. Methods Murine N9 microglial cells were challenged with lipopolysaccharide (LPS, 100 ng/mL) in the absence or in the presence of the A2AR antagonist, SCH58261 (50 nM), as well as other modulators of A2AR signaling. The BDNF cellular content and secretion were quantified by Western blotting and ELISA, A2AR density was probed by Western blotting and immunocytochemistry and cell proliferation was assessed by BrdU incorporation. Additionally, the A2AR modulation of LPS-driven cell proliferation was also tested in primary cultures of mouse microglia. Results LPS induced time-dependent changes of the intra- and extracellular levels of BDNF and increased microglial proliferation. The maximal LPS-induced BDNF release was time-coincident with an LPS-induced increase of the A2AR density. Notably, removing endogenous extracellular adenosine or blocking A2AR prevented the LPS-mediated increase of both BDNF secretion and proliferation, as well as exogenous BDNF-induced proliferation. Conclusions We conclude that A2AR activation plays a mandatory role controlling the release of BDNF from activated microglia, as well as the autocrine/paracrine proliferative role of BDNF. PMID:23363775

  4. Cell-Type Specific Determinants of NRAMP1 Expression in Professional Phagocytes

    Directory of Open Access Journals (Sweden)

    Mathieu F. M. Cellier

    2013-01-01

    Full Text Available The Natural resistance-associated macrophage protein 1 (Nramp1 or Solute carrier 11 member 1, Slc11a1 transports divalent metals across the membrane of late endosomes and lysosomes in professional phagocytes. Nramp1 represents an ancient eukaryotic cell-autonomous defense whereas the gene duplication that yielded Nramp1 and Nramp2 predated the origin of Sarcopterygians (lobe-finned fishes and tetrapods. SLC11A1 genetic polymorphisms associated with human resistance to tuberculosis consist of potential regulatory variants. Herein, current knowledge of the regulation of SLC11A1 gene expression is reviewed and comprehensive analysis of ENCODE data available for hematopoietic cell-types suggests a hypothesis for the regulation of SLC11A1 expression during myeloid development and phagocyte functional polarization. SLC11A1 is part of a 34.6 kb CTCF-insulated locus scattered with predicted regulatory elements: a 3' enhancer, a large 5' enhancer domain and four elements spread around the transcription start site (TSS, including several C/EBP and PU.1 sites. SLC11A1 locus ends appear mobilized by ETS-related factors early during myelopoiesis; activation of both 5' and 3' enhancers in myelo-monocytic cells correlate with transcription factor binding at the TSS. Characterizing the corresponding cis/trans determinants functionally will establish the mechanisms involved and possibly reveal genetic variation that impacts susceptibility to infectious or immune diseases.

  5. Adaptability and selectivity of human peroxisome proliferator-activated receptor (PPAR) pan agonists revealed from crystal structures

    International Nuclear Information System (INIS)

    Oyama, Takuji; Toyota, Kenji; Waku, Tsuyoshi; Hirakawa, Yuko; Nagasawa, Naoko; Kasuga, Jun-ichi; Hashimoto, Yuichi; Miyachi, Hiroyuki; Morikawa, Kosuke

    2009-01-01

    The structures of the ligand-binding domains (LBDs) of human peroxisome proliferator-activated receptors (PPARα, PPARγ and PPARδ) in complexes with a pan agonist, an α/δ dual agonist and a PPARδ-specific agonist were determined. The results explain how each ligand is recognized by the PPAR LBDs at an atomic level. Peroxisome proliferator-activated receptors (PPARs) belong to the nuclear hormone receptor family, which is defined as transcriptional factors that are activated by the binding of ligands to their ligand-binding domains (LBDs). Although the three PPAR subtypes display different tissue distribution patterns and distinct pharmacological profiles, they all are essentially related to fatty-acid and glucose metabolism. Since the PPARs share similar three-dimensional structures within the LBDs, synthetic ligands which simultaneously activate two or all of the PPARs could be potent candidates in terms of drugs for the treatment of abnormal metabolic homeostasis. The structures of several PPAR LBDs were determined in complex with synthetic ligands, derivatives of 3-(4-alkoxyphenyl)propanoic acid, which exhibit unique agonistic activities. The PPARα and PPARγ LBDs were complexed with the same pan agonist, TIPP-703, which activates all three PPARs and their crystal structures were determined. The two LBD–ligand complex structures revealed how the pan agonist is adapted to the similar, but significantly different, ligand-binding pockets of the PPARs. The structures of the PPARδ LBD in complex with an α/δ-selective ligand, TIPP-401, and with a related δ-specific ligand, TIPP-204, were also determined. The comparison between the two PPARδ complexes revealed how each ligand exhibits either a ‘dual selective’ or ‘single specific’ binding mode

  6. Activity of Metabotropic Glutamate Receptor 4 Suppresses Proliferation and Promotes Apoptosis With Inhibition of Gli-1 in Human Glioblastoma Cells

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    Zhichao Zhang

    2018-05-01

    Full Text Available Glioblastoma multiforme (GBM is the most lethal glioma variant in the adult brain and among the deadliest of human cancers. Increasing evidence has shown that metabotropic glutamate receptor subtype 4 (mGluR4 expression may play roles in regulating the growth of neural stem cells as well as several cancer cell lines. Here, we investigated the effects of mGluR4 on the growth and apoptosis of the LN229 GBM cell line. Involvement of Gli-1, one of the key transcription factors in the sonic Hedgehog (SHH signaling pathway, was further explored. In this study, mGluR4 was activated using selective agonist VU0155041; and gene-targeted siRNAs were used to generate loss of function of mGluR4 and Gli-1 in LN229 cells. The results demonstrated that LN229 cells expressed mGluR4 and the agonist VU0155041 decreased cell viability in a dose- and time-dependent manner. Activation of mGluR4 inhibited cyclin D1 expression, activated pro-caspase-8/9/3, and disrupted the balance of Bcl-2/Bax expression, which indicated cell cycle arrest and apoptosis of LN229 cells, respectively. Furthermore, Gli-1 expression was reduced by mGluR4 activation in LN229 cells, and downregulation of Gli-1 expression by gene-targeted siRNA resulted in both inhibition of cell proliferation and promotion of apoptosis. Moreover, VU0155041 treatment substantially blocked SHH-induced cyclin D1 expression and cell proliferation, while increasing TUNEL-positive cells and the activation of apoptosis-related proteins. We concluded that activation of mGluR4 expressed in LN229 cells could inhibit GBM cell growth by decreasing cell proliferation and promoting apoptosis. Further suppression of intracellular Gli-1 expression might be involved in the action of mGluR4 on cancer cells. Our study suggested a novel role of mGluR4, which might serve as a potential drug target for control of GBM cell growth.

  7. The perivascular phagocyte of the mouse pineal gland: An antigen-presenting cell

    DEFF Research Database (Denmark)

    Møller, Morten; Rath, Martin F; Klein, David C

    2006-01-01

    The perivascular space of the rat pineal gland is known to contain phagocytic cells that are immunoreactive for leukocyte antigens, and thus they appear to belong to the macrophage/microglial cell line. These cells also contain MHC class II proteins. We investigated this cell type in the pineal g...... for MHC class II protein and for CD68, a marker of monocytes/phagocytes. This study verifies that perivascular phagocytes with antigen-presenting properties are present in the mouse pineal gland....

  8. REX-1 expression and p38 MAPK activation status can determine proliferation/differentiation fates in human mesenchymal stem cells.

    Directory of Open Access Journals (Sweden)

    Dilli Ram Bhandari

    Full Text Available BACKGROUND: REX1/ZFP42 is a well-known embryonic stem cell (ESC marker. However, the role of REX1, itself, is relatively unknown because the function of REX1 has only been reported in the differentiation of ESCs via STAT signaling pathways. Human mesenchymal stem cells (hMSCs isolated from young tissues and cancer cells express REX1. METHODOLOGY/PRINCIPAL FINDING: Human umbilical cord blood-derived MSCs (hUCB-MSCs and adipose tissue-derived MSCs (hAD-MSCs strongly express REX1 and have a lower activation status of p38 MAPK, but bone marrow-derived MSCs (hBM-MSCs have weak REX1 expression and higher activation of p38 MAPK. These results indicated that REX1 expression in hMSCs was positively correlated with proliferation rates but inversely correlated with the phosphorylation of p38 MAPK. In hUCB-MSCs, the roles of REX1 and p38 MAPK were investigated, and a knockdown study was performed using a lentiviral vector-based small hairpin RNA (shRNA. After REX1 knockdown, decreased cell proliferation was observed. In REX1 knocked-down hUCB-MSCs, the osteogenic differentiation ability deteriorated, but the adipogenic potential increased or was similar to that observed in the controls. The phosphorylation of p38 MAPK in hUCB-MSCs significantly increased after REX1 knockdown. After p38 MAPK inhibitor treatment, the cell growth in REX1 knocked-down hUCB-MSCs almost recovered, and the suppressed expression levels of CDK2 and CCND1 were also restored. The expression of MKK3, an upstream regulator of p38 MAPK, significantly increased in REX1 knocked-down hUCB-MSCs. The direct binding of REX1 to the MKK3 gene was confirmed by a chromatin immunoprecipitation (ChIP assay. CONCLUSIONS/SIGNIFICANCE: These findings showed that REX1 regulates the proliferation/differentiation of hMSCs through the suppression of p38 MAPK signaling via the direct suppression of MKK3. Therefore, p38 MAPK and REX-1 status can determine the cell fate of adult stem cells (ASCs. These

  9. IL-7 splicing variant IL-7δ5 induces human breast cancer cell proliferation via activation of PI3K/Akt pathway

    International Nuclear Information System (INIS)

    Pan, Deshun; Liu, Bing; Jin, Xiaobao; Zhu, Jiayong

    2012-01-01

    Highlights: ► This study confirms the role of IL-7δ5 in breast cancer cell proliferation. ► IL-7δ5 promotes breast cancer cell proliferation and cell cycle progression. ► IL-7δ5 promotes cell proliferation via activation of PI3K/Akt pathway. -- Abstract: Various tumor cells express interleukin 7 (IL-7) and IL-7 variants. IL-7 has been confirmed to stimulate solid tumor cell proliferation. However, the effect of IL-7 variants on tumor cell proliferation remains unclear. In this study, we evaluated the role of IL-7δ5 (an IL-7 variant lacking exon 5) on proliferation and cell cycle progression of human MDA-MB-231 and MCF-7 breast cancer cells. The results showed that IL-7δ5 promoted cell proliferation and cell cycle progression from G1 phase to G2/M phase, associated with upregulation of cyclin D1 expression and the downregulation of p27 kip1 expression. Mechanistically, we found that IL-7δ5 induced the activation of Akt. Inhibition of PI3K/Akt pathway by LY294002 reversed the proliferation and cell cycle progression of MDA-MB-231 and MCF-7 cells induced by IL-7δ5. In conclusion, our findings demonstrate that IL-7δ5 variant induces human breast cancer cell proliferation and cell cycle progression via activation of PI3K/Akt pathway. Thus, IL-7δ5 may be a potential target for human breast cancer therapeutics intervention.

  10. Tumor-induced loss of mural Connexin 43 gap junction activity promotes endothelial proliferation

    International Nuclear Information System (INIS)

    Choudhary, Mayur; Naczki, Christine; Chen, Wenhong; Barlow, Keith D.; Case, L. Douglas; Metheny-Barlow, Linda J.

    2015-01-01

    Proper functional association between mural cells and endothelial cells (EC) causes EC of blood vessels to become quiescent. Mural cells on tumor vessels exhibit decreased attachment to EC, which allows vessels to be unstable and proliferative. The mechanisms by which tumors prevent proper association between mural cells and EC are not well understood. Since gap junctions (GJ) play an important role in cell-cell contact and communication, we investigated whether loss of GJ plays a role in tumor-induced mural cell dissociation. Mural cell regulation of endothelial proliferation was assessed by direct co-culture assays of fluorescently labeled cells quantified by flow cytometry or plate reader. Gap junction function was assessed by parachute assay. Connexin 43 (Cx43) protein in mural cells exposed to conditioned media from cancer cells was assessed by Western and confocal microscopy; mRNA levels were assessed by quantitative real-time PCR. Expression vectors or siRNA were utilized to overexpress or knock down Cx43. Tumor growth and angiogenesis was assessed in mouse hosts deficient for Cx43. Using parachute dye transfer assay, we demonstrate that media conditioned by MDA-MB-231 breast cancer cells diminishes GJ communication between mural cells (vascular smooth muscle cells, vSMC) and EC. Both protein and mRNA of the GJ component Connexin 43 (Cx43) are downregulated in mural cells by tumor-conditioned media; media from non-tumorigenic MCF10A cells had no effect. Loss of GJ communication by Cx43 siRNA knockdown, treatment with blocking peptide, or exposure to tumor-conditioned media diminishes the ability of mural cells to inhibit EC proliferation in co-culture assays, while overexpression of Cx43 in vSMC restores GJ and endothelial inhibition. Breast tumor cells implanted into mice heterozygous for Cx43 show no changes in tumor growth, but exhibit significantly increased tumor vascularization determined by CD31 staining, along with decreased mural cell support

  11. Hacker Within! Ehrlichia chaffeensis Effector Driven Phagocyte Reprogramming Strategy

    Directory of Open Access Journals (Sweden)

    Taslima Taher Lina

    2016-05-01

    Full Text Available Ehrlichia chaffeensis is a small, gram negative, obligately intracellular bacterium that preferentially infects mononuclear phagocytes. It is the etiologic agent of human monocytotropic ehrlichiosis (HME, an emerging life-threatening tick-borne zoonosis. Mechanisms by which E. chaffeensis establishes intracellular infection, and avoids host defenses are not well understood, but involve functionally relevant host-pathogen interactions associated with tandem and ankyrin repeat effector proteins. In this review, we discuss the recent advances in our understanding of the molecular and cellular mechanisms that underlie Ehrlichia host cellular reprogramming strategies that enable intracellular survival.

  12. Mononuclear phagocytes as a target, not a barrier, for drug delivery.

    Science.gov (United States)

    Yong, Seok-Beom; Song, Yoonsung; Kim, Hyung Jin; Ain, Qurrat Ul; Kim, Yong-Hee

    2017-08-10

    Mononuclear phagocytes have been generally recognized as a barrier to drug delivery. Recently, a new understanding of mononuclear phagocytes (MPS) ontogeny has surfaced and their functions in disease have been unveiled, demonstrating the need for re-evaluation of perspectives on mononuclear phagocytes in drug delivery. In this review, we described mononuclear phagocyte biology and focus on their accumulation mechanisms in disease sites with explanations of monocyte heterogeneity. In the 'MPS as a barrier' section, we summarized recent studies on mechanisms to avoid phagocytosis based on two different biological principles: protein adsorption and self-recognition. In the 'MPS as a target' section, more detailed descriptions were given on mononuclear phagocyte-targeted drug delivery systems and their applications to various diseases. Collectively, we emphasize in this review that mononuclear phagocytes are potent targets for future drug delivery systems. Mononuclear phagocyte-targeted delivery systems should be created with an understanding of mononuclear phagocyte ontogeny and pathology. Each specific subset of phagocytes should be targeted differently by location and function for improved disease-drug delivery while avoiding RES clearance such as Kupffer cells and splenic macrophages. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Phenotype and cell proliferation activity of duct-like structures in human sublingual glands: a histological and immunohistochemical study

    Directory of Open Access Journals (Sweden)

    Elen de Souza TOLENTINO

    2015-06-01

    Full Text Available There are several age-related microscopic changes in the salivary glands, including the increase in the number of duct-like structures (DLS. However, the true origin and the phenotype of the DLS are not known. Objective To evaluate the phenotype and the cell proliferation index of the DLS of human sublingual glands. Material and Methods Sixty sublingual glands obtained from human cadavers were divided into two groups - 0-30 and 61-90 years old. The phenotype was estimated by immunostaining for cytokeratin 19 (CK 19 and the S-100 protein as well as by the presence of mucin and glycogen. The cell proliferation index was determined by the Ki-67 antibody. The histochemical techniques used periodic acid-Schiff (PAS and Alcian Blue. In each captured microscopic field, the DLS were counted to establish a percentage for the staining profile. The statistical analysis was accomplished using Student's t-test, the Mann-Whitney test and Pearson's correlation coefficient (p<0.05. Results Comparing both groups, only CK 19 showed a statistically significant difference (p=0.033, with the strongest expression in the elderly group. There was no significant difference between PAS and Alcian Blue (p=0.270. In both groups, the immunostaining for CK 19 was stronger than that for S-100 (p=0.004;p<0.001, but there was no correlation between the two immunomarkers (ρ=-0.163; p=0.315. There was no immunostaining for Ki-67. Conclusions DLS demonstrate a ductal phenotypic profile and do not present cell proliferation activity. DLS may represent a regressive process arising from acini or represent the result of metaplasia.

  14. Correlation of contrast-enhanced ultrasound parameters with oncogene expression and cell proliferation activity in breast cancer

    Institute of Scientific and Technical Information of China (English)

    Ce Zhang

    2017-01-01

    Objective: To study the correlation of contrast-enhanced ultrasound parameters with oncogene expression and cell proliferation activity in breast cancer. Methods: Breast cancer lesions and benign breast lesions surgically removed in Zigong Third People's Hospital between May 2014 and February 2017 were selected, contrast-enhanced ultrasound was done before operation to draw the time-intensity curve and calculate the area under the curve (AUC), and the expression of proliferation molecules and tumor suppressor genes were detected after operation. Results:The contrast-enhanced ultrasound parameter AUC of the breast cancer lesion was greatly higher than that of the benign breast lesion; ECT2, ZKSCAN3, USP39 and EphA2 mRNA expression in breast cancer lesions were obviously higher than those in benign breast lesions whereas HPK1, TCEAL17, CCN5, ATG2B and ATG4D mRNA expression were greatly lower than those in benign breast lesions; ECT2, ZKSCAN3, USP39 and EphA2 mRNA expression in breast cancer lesions with high AUC were greatly higher than those in breast cancer lesions with low AUC whereas HPK1, TCEAL17, CCN5, ATG2B and ATG4D mRNA expression were greatly lower than those in breast cancer lesions with low AUC. Conclusion: The contrast-enhanced ultrasound parameter AUC of breast cancer lesion significantly increases and is closely related to the higher expression of pro-proliferation molecules and the lower expression of tumor suppressor genes.

  15. VEGF induces proliferation of human hair follicle dermal papilla cells through VEGFR-2-mediated activation of ERK

    International Nuclear Information System (INIS)

    Li, Wei; Man, Xiao-Yong; Li, Chun-Ming; Chen, Jia-Qi; Zhou, Jiong; Cai, Sui-Qing; Lu, Zhong-Fa; Zheng, Min

    2012-01-01

    Vascular endothelial growth factor (VEGF) is one of the strongest regulators of physiological and pathological angiogenesis. VEGF receptor 2 (VEGFR-2), the primary receptor for VEGF, is thought to mediate major functional effects of VEGF. Previously, we have localized both VEGF and VEGFR-2 in human hair follicles. In this study, we further defined the expression and roles of VEGFR-2 on human hair follicle dermal papilla (DP) cells. The expression of VEGFR-2 on DP cells was examined by reverse transcription-polymerase chain reaction (RT-PCR) and Western blot analysis separately, and localization of VEGFR-2 was defined by immunofluorescence. The effect of VEGF on DP cells was analyzed by MTT assays and specific inhibitors. Finally, the role of VEGF involved in the signaling pathways was investigated by Western blot. RT-PCR and Western blot analysis demonstrated the expression of VEGFR-2 on DP cells. Immunostaining for VEGFR-2 showed strong signal on cultured human DP cells in vitro. Exogenous VEGF 165 stimulated proliferation of DP cells in a dose-dependent manner. Furthermore, this stimulation was blocked by a VEGFR-2 neutralizing antibody (MAB3571) and an ERK inhibitor (PD98059). VEGF 165 -induced phosphorylation of ERK1/2 was abolished by MAB3571 and PD98059, while the phosphorylation of p38, JNK and AKT were not changed by VEGF 165 . Taken together, VEGFR-2 is expressed on primary human hair follicle DP cells and VEGF induces proliferation of DP cells through VEGFR-2/ERK pathway, but not p38, JNK or AKT signaling. -- Highlights: ► We examine the expression of VEGFR-2 on cultured human dermal papilla (DP) cells. ► VEGF 165 stimulated proliferation of human DP cells in a dose-dependent manner. ► This stimulation was through VEGFR-2-mediated activation of ERK.

  16. Engineered Biomaterials Control Differentiation and Proliferation of Human-Embryonic-Stem-Cell-Derived Cardiomyocytes via Timed Notch Activation

    Directory of Open Access Journals (Sweden)

    Jason C. Tung

    2014-03-01

    Full Text Available For cell-based treatments of myocardial infarction, a better understanding of key developmental signaling pathways and more robust techniques for producing cardiomyocytes are required. Manipulation of Notch signaling has promise as it plays an important role during cardiovascular development, but previous studies presented conflicting results that Notch activation both positively and negatively regulates cardiogenesis. We developed surface- and microparticle-based Notch-signaling biomaterials that function in a time-specific activation-tunable manner, enabling precise investigation of Notch activation at specific developmental stages. Using our technologies, a biphasic effect of Notch activation on cardiac differentiation was found: early activation in undifferentiated human embryonic stem cells (hESCs promotes ectodermal differentiation, activation in specified cardiovascular progenitor cells increases cardiac differentiation. Signaling also induces cardiomyocyte proliferation, and repeated doses of Notch-signaling microparticles further enhance cardiomyocyte population size. These results highlight the diverse effects of Notch activation during cardiac development and provide approaches for generating large quantities of cardiomyocytes.

  17. Peroxisome Proliferator-Activated Receptor- Is a Potent Target for Prevention and Treatment in Human Prostate and Testicular Cancer

    Directory of Open Access Journals (Sweden)

    Masahide Matsuyama

    2008-01-01

    Full Text Available Peroxisome proliferator-activated receptor- (PPAR- is a ligand-activated transcriptional factor belonging to steroid receptor superfamily. PPAR- plays a role in both adipocyte differentiation and tumorigenesis. Up to date, PPAR- is expressed in various cancer tissues, and PPAR- ligand induces growth arrest of these cancer cells. In this study, we examined the expression of PPAR- in prostate cancer (PC and testicular cancer (TC by RT-PCR and immunohistochemistry, and we also examined the effect of PPAR- ligand in these cells by MTT assay, hoechest staining, and flow cytometry. PPAR- expression was significantly more extensive and intense in malignant tissues than in normal tissues. PPAR- ligand induced the reduction of malignant cell viability through apoptosis. These results demonstrated that the generated PPAR- in PC and TC cells might play an important role in the tumorigenesis. PPAR- may become a new target in the treatment of PC and TC.

  18. The Role of Peroxisome Proliferator-Activated Receptor β/δ on the Inflammatory Basis of Metabolic Disease

    Directory of Open Access Journals (Sweden)

    Teresa Coll

    2010-01-01

    Full Text Available The pathophysiology underlying several metabolic diseases, such as obesity, type 2 diabetes mellitus, and atherosclerosis, involves a state of chronic low-level inflammation. Evidence is now emerging that the nuclear receptor Peroxisome Proliferator-Activated Receptor (PPARβ/δ ameliorates these pathologies partly through its anti-inflammatory effects. PPARβ/δ activation prevents the production of inflammatory cytokines by adipocytes, and it is involved in the acquisition of the anti-inflammatory phenotype of macrophages infiltrated in adipose tissue. Furthermore, PPARβ/δ ligands prevent fatty acid-induced inflammation in skeletal muscle cells, avoid the development of cardiac hypertrophy, and suppress macrophage-derived inflammation in atherosclerosis. These data are promising and suggest that PPARβ/δ ligands may become a therapeutic option for preventing the inflammatory basis of metabolic diseases.

  19. Activation of Group II Metabotropic Glutamate Receptors Increases Proliferation but does not Influence Neuronal Differentiation of a Human Neural Stem Cell Line

    DEFF Research Database (Denmark)

    Dindler, Anne; Blaabjerg, Morten; Kamand, Morad

    2018-01-01

    of pharmacological activation and inhibition of mGluR2/3 on proliferation, differentiation and viability of a human neural stem cell line. Immunofluorescence staining revealed the presence of mGluR2/3 receptors on both proliferating and differentiating stem cells, including cells differentiated into β-tubulin III....... Western blot analysis revealed that the active, dimeric form of mGluR2/3 was mainly present on the proliferating cells, which may explain our findings. The present study emphasises the importance of glutamate and mGluRs on regulation of human neural stem cells and suggests a significant role of mGluR2....../3 during cell proliferation. This article is protected by copyright. All rights reserved....

  20. Magnolol Alleviates Inflammatory Responses and Lipid Accumulation by AMP-Activated Protein Kinase-Dependent Peroxisome Proliferator-Activated Receptor α Activation

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    Ye Tian

    2018-02-01

    Full Text Available Magnolol (MG is a kind of lignin isolated from Magnolia officinalis, which serves several different biological functions, such as antifungal, anticancer, antioxidant, and hepatoprotective functions. This study aimed to evaluate the protective effect of MG against oleic acid (OA-induced hepatic steatosis and inflammatory damage in HepG2 cells and in a tyloxapol (Ty-induced hyperlipidemia mouse model. Our findings indicated that MG can effectively inhibit OA-stimulated tumor necrosis factor α (TNF-α secretion, reactive oxygen species generation, and triglyceride (TG accumulation. Further study manifested that MG significantly suppressed OA-activated mitogen-activated protein kinase (MAPK and nuclear factor-kappa B (NF-κB signaling pathways and that these inflammatory responses can be negated by pretreatment with inhibitors of extracellular regulated protein kinase and c-Jun N-terminal kinase (U0126 and SP600125, respectively. In addition, MG dramatically upregulated peroxisome proliferator-activated receptor α (PPARα translocation and reduced sterol regulatory element-binding protein 1c (SREBP-1c protein synthesis and excretion, both of which are dependent upon the phosphorylation of adenosine monophosphate (AMP-activated protein kinase (AMPK, acetyl-CoA carboxylase, and AKT kinase (AKT. However, MG suspended the activation of PPARα expression and was thus blocked by pretreatment with LY294002 and compound c (specific inhibitors of AKT and AMPK. Furthermore, MG clearly alleviated serum TG and total cholesterol release; upregulated AKT, AMPK, and PPARα expression; suppressed SREBP-1c generation; and alleviated hepatic steatosis and dyslipidemia in Ty-induced hyperlipidemia mice. Taken together, these results suggest that MG exerts protective effects against steatosis, hyperlipidemia, and the underlying mechanism, which may be closely associated with AKT/AMPK/PPARα activation and MAPK/NF-κB/SREBP-1c inhibition.

  1. Far beyond Phagocytosis: Phagocyte-Derived Extracellular Traps Act Efficiently against Protozoan Parasites In Vitro and In Vivo

    Directory of Open Access Journals (Sweden)

    Liliana M. R. Silva

    2016-01-01

    Full Text Available Professional mononuclear phagocytes such as polymorphonuclear neutrophils (PMN, monocytes, and macrophages are considered as the first line of defence against invasive pathogens. The formation of extracellular traps (ETs by activated mononuclear phagocytes is meanwhile well accepted as an effector mechanism of the early host innate immune response acting against microbial infections. Recent investigations showed evidence that ETosis is a widely spread effector mechanism in vertebrates and invertebrates being utilized to entrap and kill bacteria, fungi, viruses, and protozoan parasites. ETs are released in response to intact protozoan parasites or to parasite-specific antigens in a controlled cell death process. Released ETs consist of nuclear DNA as backbone adorned with histones, antimicrobial peptides, and phagocyte-specific granular enzymes thereby producing a sticky extracellular matrix capable of entrapping and killing pathogens. This review summarizes recent data on protozoa-induced ETosis. Special attention will be given to molecular mechanisms of protozoa-induced ETosis and on its consequences for the parasites successful reproduction and life cycle accomplishment.

  2. Peroxisome Proliferator-Activated Receptor-alpha Gene Level Differently Affects Lipid Metabolism and Inflammation in Apolipoprotein E2 Knock-In Mice

    NARCIS (Netherlands)

    Lalloyer, Fanny; Wouters, Kristiaan; Baron, Morgane; Caron, Sandrine; Vallez, Emmanuelle; Vanhoutte, Jonathan; Bauge, Eric; Shiri-Sverdlov, Ronit; Hofker, Marten; Staels, Bart; Tailleux, Anne

    Objective-Peroxisome proliferator-activated receptor-alpha (PPAR alpha) is a ligand-activated transcription factor that controls lipid metabolism and inflammation. PPAR alpha is activated by fibrates, hypolipidemic drugs used in the treatment of dyslipidemia. Previous studies assessing the influence

  3. Transforming growth factor alpha (TGFα regulates granulosa cell tumor (GCT cell proliferation and migration through activation of multiple pathways.

    Directory of Open Access Journals (Sweden)

    Cheng Wang

    Full Text Available Granulosa cell tumors (GCTs are the most common ovarian estrogen producing tumors, leading to symptoms of excessive estrogen such as endometrial hyperplasia and endometrial adenocarcinoma. These tumors have malignant potential and often recur. The etiology of GCT is unknown. TGFα is a potent mitogen for many different cells. However, its function in GCT initiation, progression and metastasis has not been determined. The present study aims to determine whether TGFα plays a role in the growth of GCT cells. KGN cells, which are derived from an invasive GCT and have many features of normal granulosa cells, were used as the cellular model. Immunohistochemistry, Western blot and RT-PCR results showed that the ErbB family of receptors is expressed in human GCT tissues and GCT cell lines. RT-PCR results also indicated that TGFα and EGF are expressed in the human granulosa cells and the GCT cell lines, suggesting that TGFα might regulate GCT cell function in an autocrine/paracrine manner. TGFα stimulated KGN cell DNA synthesis, cell proliferation, cell viability, cell cycle progression, and cell migration. TGFα rapidly activated EGFR/PI3K/Akt and mTOR pathways, as indicated by rapid phosphorylation of Akt, TSC2, Rictor, mTOR, P70S6K and S6 proteins following TGFα treatment. TGFα also rapidly activated the EGFR/MEK/ERK pathway, and P38 MAPK pathways, as indicated by the rapid phosphorylation of EGFR, MEK, ERK1/2, P38, and CREB after TGFα treatment. Whereas TGFα triggered a transient activation of Akt, it induced a sustained activation of ERK1/2 in KGN cells. Long-term treatment of KGN cells with TGFα resulted in a significant increase in cyclin D2 and a decrease in p27/Kip1, two critical regulators of granulosa cell proliferation and granulosa cell tumorigenesis. In conclusion, TGFα, via multiple signaling pathways, regulates KGN cell proliferation and migration and may play an important role in the growth and metastasis of GCTs.

  4. HSPC159 promotes proliferation and metastasis via inducing EMT and activating PI3K/Akt pathway in breast cancer.

    Science.gov (United States)

    Zheng, Jie; Zhang, Mengxue; Zhang, Liying; Ding, Xiaodi; Li, Wentong; Lu, Shijun

    2018-05-08

    HSPC159 is a novel human galectin-related protein and has been shown to involved in the carcinogenesis. Little is known about HSPC159 expression and function in breast cancer. Here we showed that HSPC159 was aberrantly expressed in both breast cancer cell lines and tumor tissues and that its expression was associated with poor prognosis of breast cancer patients. Using gain- and loss-of-function methods we found that HSPC159 enhanced breast cancer cells proliferation and metastasis in vitro and in vivo. Mechanistically, HSPC159 was found to induce epithelial-mesenchymal transition (EMT) and F-actin polymerization process of breast cancer cells. Moreover, HSPC159 promoted proliferation, migration and invasion through activating PI3K/Akt signaling pathway in breast cancer. In conclusion, our findings demonstrated that HSPC159 contributed to breast cancer progression via PI3K/Akt pathway and might serve as a potential therapeutic target for the treatment of breast cancer. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  5. Peroxisome Proliferator-Activated Receptor γ Induces the Expression of Tissue Factor Pathway Inhibitor-1 (TFPI-1 in Human Macrophages

    Directory of Open Access Journals (Sweden)

    G. Chinetti-Gbaguidi

    2016-01-01

    Full Text Available Tissue factor (TF is the initiator of the blood coagulation cascade after interaction with the activated factor VII (FVIIa. Moreover, the TF/FVIIa complex also activates intracellular signalling pathways leading to the production of inflammatory cytokines. The TF/FVIIa complex is inhibited by the tissue factor pathway inhibitor-1 (TFPI-1. Peroxisome proliferator-activated receptor gamma (PPARγ is a transcription factor that, together with PPARα and PPARβ/δ, controls macrophage functions. However, whether PPARγ activation modulates the expression of TFP1-1 in human macrophages is not known. Here we report that PPARγ activation increases the expression of TFPI-1 in human macrophages in vitro as well as in vivo in circulating peripheral blood mononuclear cells. The induction of TFPI-1 expression by PPARγ ligands, an effect shared by the activation of PPARα and PPARβ/δ, occurs also in proinflammatory M1 and in anti-inflammatory M2 polarized macrophages. As a functional consequence, treatment with PPARγ ligands significantly reduces the inflammatory response induced by FVIIa, as measured by variations in the IL-8, MMP-2, and MCP-1 expression. These data identify a novel role for PPARγ in the control of TF the pathway.

  6. Celecoxib induces proliferation and Amphiregulin production in colon subepithelial myofibroblasts, activating erk1-2 signaling in synergy with EGFR.

    Science.gov (United States)

    Benelli, Roberto; Venè, Roberta; Minghelli, Simona; Carlone, Sebastiano; Gatteschi, Beatrice; Ferrari, Nicoletta

    2013-01-01

    The COX-2 inhibitor Celecoxib, tested in phase III trials for the prevention of sporadic colon adenomas, reduced the appearance of new adenomas, but was unable to affect the incidence of colon cancer. Moreover the 5years follow-up showed that patients discontinuing Celecoxib treatment had an increased incidence of adenomas as compared to the placebo arm. In the APC(min/+) mouse model short term treatment with Celecoxib reduced gut adenomas, but a prolonged administration of the drug induced fibroblast activation and intestinal fibrosis with a final tumor burden. The way Celecoxib could directly activate human colon myofibroblasts (MF) has not yet been investigated. We found that MF are activated by non toxic doses of Celecoxib. Celecoxib induces erk1-2 and Akt phosphorylation within 5'. This short term activation is apparently insufficient to cause phenotypic changes, but the contemporary triggering of EGFR causes an impressive synergic effect inducing MF proliferation and the neo-expression and release of Amphiregulin (AREG), a well known EGFR agonist involved in colon cancer progression. As a confirm to these observations, the erk inhibitor U0126 and the EGFR inhibitors Tyrphostin and Cetuximab were able to contrast AREG induction. Our data provide evidence that Celecoxib directly activates MF empowering EGFR signaling. According to these results the association with EGFR (or erk1-2) inhibitors could abolish the off-target activity of Celecoxib, possibly extending the potential of this drug for colon cancer prevention. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  7. Human mesenchymal stem cell proliferation is regulated by PGE2 through differential activation of cAMP-dependent protein kinase isoforms

    International Nuclear Information System (INIS)

    Kleiveland, Charlotte Ramstad; Kassem, Moustapha; Lea, Tor

    2008-01-01

    The conditions used for in vitro differentiation of hMSCs contain substances that affect the activity and expression of cyclooxygenase enzymes (COX1/COX2) and thereby the synthesis of prostanoids. hMSC constitutively produce PGE2 when cultivated in vitro. In this study we have investigated effects of PGE2 on proliferation of hMSC. We here demonstrate that one of the main control molecules in the Wnt pathway, GSK-3β, is phosphorylated at the negative regulatory site ser-9 after treating the cells with PGE2. This phosphorylation is mediated by elevation of cAMP and subsequent activation of PKA. Furthermore, PGE2 treatment leads to enhanced nuclear translocation of β-catenin, thus influencing cell proliferation. The presence of two PKA isoforms, types I and II, prompted us to investigate their individual contribution in PGE2-mediated regulation of proliferation. Specific activation of PKA type II with synthetic cAMP analogues, resulted in enhancement of proliferation. On the other side, we found that treatment of hMSC with high concentrations of PGE2 inhibited cell proliferation by arresting the cells in G 0 /G 1 phase, an effect we found to be mediated by PKA I. Hence, the two different PKA isoforms seem to have opposing functions in the regulation of proliferation and differentiation in these cells

  8. Divergence of macrophage phagocytic and antimicrobial programs in leprosy.

    Science.gov (United States)

    Montoya, Dennis; Cruz, Daniel; Teles, Rosane M B; Lee, Delphine J; Ochoa, Maria Teresa; Krutzik, Stephan R; Chun, Rene; Schenk, Mirjam; Zhang, Xiaoran; Ferguson, Benjamin G; Burdick, Anne E; Sarno, Euzenir N; Rea, Thomas H; Hewison, Martin; Adams, John S; Cheng, Genhong; Modlin, Robert L

    2009-10-22

    Effective innate immunity against many microbial pathogens requires macrophage programs that upregulate phagocytosis and direct antimicrobial pathways, two functions generally assumed to be coordinately regulated. We investigated the regulation of these key functions in human blood-derived macrophages. Interleukin-10 (IL-10) induced the phagocytic pathway, including the C-type lectin CD209 and scavenger receptors, resulting in phagocytosis of mycobacteria and oxidized low-density lipoprotein. IL-15 induced the vitamin D-dependent antimicrobial pathway and CD209, yet the cells were less phagocytic. The differential regulation of macrophage functional programs was confirmed by analysis of leprosy lesions: the macrophage phagocytosis pathway was prominent in the clinically progressive, multibacillary form of the disease, whereas the vitamin D-dependent antimicrobial pathway predominated in the self-limited form and in patients undergoing reversal reactions from the multibacillary to the self-limited form. These data indicate that macrophage programs for phagocytosis and antimicrobial responses are distinct and differentially regulated in innate immunity to bacterial infections.

  9. Anti-kindling Effect of Bezafibrate, a Peroxisome Proliferator-activated Receptors Alpha Agonist, in Pentylenetetrazole Induced Kindling Seizure Model.

    Science.gov (United States)

    Saha, Lekha; Bhandari, Swati; Bhatia, Alka; Banerjee, Dibyajyoti; Chakrabarti, Amitava

    2014-12-01

    Studies in the animals suggested that Peroxisome proliferators activated receptors (PPARs) may be involved in seizure control and selective agonists of PPAR α or PPAR γ raise seizure thresholds. The present study was contemplated with the aim of evaluating the anti kindling effects and the mechanism of bezafibrate, a Peroxisome proliferator-activated receptors α (PPAR-α) agonist in pentylenetetrazole (PTZ) induced kindling model of seizures in rats. In a PTZ kindled Wistar rat model, different doses of bezafibrate (100 mg/kg, 200 mg/kg and 300 mg/kg) were administered intraperitoneally 30 minutes before the PTZ injection. The PTZ injection was given on alternate day till the animal became fully kindled or till 10 weeks. The parameters measured were the latency to develop kindling and incidence of kindling, histopathological study of hippocampus, hippocampal lipid peroxidation studies, serum neuron specific enolase, and hippocampal DNA fragmentation study. In this study, bezafibrate significantly reduced the incidence of kindling in PTZ treated rats and exhibited a marked prolongation in the latencies to seizures. In the present study bezafibrate decreased the thiobarbituric acid-reactive substance i.e. Malondialdehyde levels, increased the reduced glutathione levels, catalase and superoxide dismutase activity in the brain. This added to its additional neuroprotective effects. Bezafibrate also reduced the neuronal damage and apoptosis in hippocampal area of the brain. Therefore bezafibrate exerted anticonvulsant properties in PTZ induced kindling model in rats. These findings may provide insights into the understanding of the mechanism of bezafibrate as an anti kindling agent and could offer a useful support to the basic antiepileptic therapy in preventing the development of PTZ induced seizures, suggesting its potential for therapeutic applications in temporal lobe epilepsy.

  10. Novel keto-phospholipids are generated by monocytes and macrophages, detected in cystic fibrosis, and activate peroxisome proliferator-activated receptor-γ.

    Science.gov (United States)

    Hammond, Victoria J; Morgan, Alwena H; Lauder, Sarah; Thomas, Christopher P; Brown, Sarah; Freeman, Bruce A; Lloyd, Clare M; Davies, Jane; Bush, Andrew; Levonen, Anna-Liisa; Kansanen, Emilia; Villacorta, Luis; Chen, Y Eugene; Porter, Ned; Garcia-Diaz, Yoel M; Schopfer, Francisco J; O'Donnell, Valerie B

    2012-12-07

    12/15-Lipoxygenases (LOXs) in monocytes and macrophages generate novel phospholipid-esterified eicosanoids. Here, we report the generation of two additional families of related lipids comprising 15-ketoeicosatetraenoic acid (KETE) attached to four phosphatidylethanolamines (PEs). The lipids are generated basally by 15-LOX in IL-4-stimulated monocytes, are elevated on calcium mobilization, and are detected at increased levels in bronchoalveolar lavage fluid from cystic fibrosis patients (3.6 ng/ml of lavage). Murine peritoneal macrophages generate 12-KETE-PEs, which are absent in 12/15-LOX-deficient mice. Inhibition of 15-prostaglandin dehydrogenase prevents their formation from exogenous 15-hydroxyeicosatetraenoic acid-PE in human monocytes. Both human and murine cells also generated analogous hydroperoxyeicosatetraenoic acid-PEs. The electrophilic reactivity of KETE-PEs is shown by their Michael addition to glutathione and cysteine. Lastly, both 15-hydroxyeicosatetraenoic acid-PE and 15-KETE-PE activated peroxisome proliferator-activated receptor-γ reporter activity in macrophages in a dose-dependent manner. In summary, we demonstrate novel peroxisome proliferator-activated receptor-γ-activating oxidized phospholipids generated enzymatically by LOX and 15-prostaglandin dehydrogenase in primary monocytic cells and in a human Th2-related lung disease. The lipids are a new family of bioactive mediators from the 12/15-LOX pathway that may contribute to its known anti-inflammatory actions in vivo.

  11. Phytol directly activates peroxisome proliferator-activated receptor α (PPARα) and regulates gene expression involved in lipid metabolism in PPARα-expressing HepG2 hepatocytes

    International Nuclear Information System (INIS)

    Goto, Tsuyoshi; Takahashi, Nobuyuki; Kato, Sota; Egawa, Kahori; Ebisu, Shogo; Moriyama, Tatsuya; Fushiki, Tohru; Kawada, Teruo

    2005-01-01

    The peroxisome proliferator-activated receptor (PPAR) is one of the indispensable transcription factors for regulating lipid metabolism in various tissues. In our screening for natural compounds that activate PPAR using luciferase assays, a branched-carbon-chain alcohol (a component of chlorophylls), phytol, has been identified as a PPARα-specific activator. Phytol induced the increase in PPARα-dependent luciferase activity and the degree of in vitro binding of a coactivator, SRC-1, to GST-PPARα. Moreover, the addition of phytol upregulated the expression of PPARα-target genes at both mRNA and protein levels in PPARα-expressing HepG2 hepatocytes. These findings indicate that phytol is functional as a PPARα ligand and that it stimulates the expression of PPARα-target genes in intact cells. Because PPARα activation enhances circulating lipid clearance, phytol may be important in managing abnormalities in lipid metabolism

  12. Differential TOR activation and cell proliferation in Arabidopsis root and shoot apexes.

    Science.gov (United States)

    Li, Xiaojuan; Cai, Wenguo; Liu, Yanlin; Li, Hui; Fu, Liwen; Liu, Zengyu; Xu, Lin; Liu, Hongtao; Xu, Tongda; Xiong, Yan

    2017-03-07

    The developmental plasticity of plants relies on the remarkable ability of the meristems to integrate nutrient and energy availability with environmental signals. Meristems in root and shoot apexes share highly similar molecular players but are spatially separated by soil. Whether and how these two meristematic tissues have differential activation requirements for local nutrient, hormone, and environmental cues (e.g., light) remain enigmatic in photosynthetic plants. Here, we report that the activation of root and shoot apexes relies on distinct glucose and light signals. Glucose energy signaling is sufficient to activate target of rapamycin (TOR) kinase in root apexes. In contrast, both the glucose and light signals are required for TOR activation in shoot apexes. Strikingly, exogenously applied auxin is able to replace light to activate TOR in shoot apexes and promote true leaf development. A relatively low concentration of auxin in the shoot and high concentration of auxin in the root might be responsible for this distinctive light requirement in root and shoot apexes, because light is required to promote auxin biosynthesis in the shoot. Furthermore, we reveal that the small GTPase Rho-related protein 2 (ROP2) transduces light-auxin signal to activate TOR by direct interaction, which, in turn, promotes transcription factors E2Fa,b for activating cell cycle genes in shoot apexes. Consistently, constitutively activated ROP2 plants stimulate TOR in the shoot apex and cause true leaf development even without light. Together, our findings establish a pivotal hub role of TOR signaling in integrating different environmental signals to regulate distinct developmental transition and growth in the shoot and root.

  13. Oncogenic K-Ras Activates p38 to Maintain Colorectal Cancer Cell Proliferation during MEK Inhibition

    Directory of Open Access Journals (Sweden)

    Winan J. van Houdt

    2010-01-01

    Full Text Available Background: Colon carcinomas frequently contain activating mutations in the K-ras proto-oncogene. K-ras itself is a poor drug target and drug development efforts have mostly focused on components of the classical Ras-activated MEK/ERK pathway. Here we have studied whether endogenous oncogenic K-ras affects the dependency of colorectal tumor cells on MEK/ERK signaling.

  14. CD8+ T lymphocyte expansion, proliferation and activation in dengue fever.

    Directory of Open Access Journals (Sweden)

    Andréia Manso de Matos

    2015-02-01

    Full Text Available Dengue fever induces a robust immune response, including massive T cell activation. The level of T cell activation may, however, be associated with more severe disease. In this study, we explored the level of CD8+ T lymphocyte activation in the first six days after onset of symptoms during a DENV2 outbreak in early 2010 on the coast of São Paulo State, Brazil. Using flow cytometry we detected a progressive increase in the percentage of CD8+ T cells in 74 dengue fever cases. Peripheral blood mononuclear cells from 30 cases were thawed and evaluated using expanded phenotyping. The expansion of the CD8+ T cells was coupled with increased Ki67 expression. Cell activation was observed later in the course of disease, as determined by the expression of the activation markers CD38 and HLA-DR. This increased CD8+ T lymphocyte activation was observed in all memory subsets, but was more pronounced in the effector memory subset, as defined by higher CD38 expression. Our results show that most CD8+ T cell subsets are expanded during DENV2 infection and that the effector memory subset is the predominantly affected sub population.

  15. Peroxisome Proliferator-Activated Receptor (PPAR) in Regenerative Medicine: Molecular Mechanism for PPAR in Stem Cells' Adipocyte Differentiation.

    Science.gov (United States)

    Xie, Qiang; Tian, Taoran; Chen, Zhaozhao; Deng, Shuwen; Sun, Ke; Xie, Jing; Cai, Xiaoxiao

    2016-01-01

    Regenerative medicine plays an indispensable role in modern medicine and many trials and researches have therefore been developed to fit our medical needs. Tissue engineering has proven that adipose tissue can widely be used and brings advantages to regenerative medicine. Moreover, a trait of adipose stem cells being isolated and grown in vitro is a cornerstone to various applications. Since the adipose tissue has been widely used in regenerative medicine, numerous studies have been conducted to seek methods for gaining more adipocytes. To investigate molecular mechanism for adipocyte differentiation, peroxisome proliferator-activated receptor (PPAR) has been widely studied to find out its functional mechanism, as a key factor for adipocyte differentiation. However, the precise molecular mechanism is still unknown. This review thus summarizes recent progress on the study of molecular mechanism and role of PPAR in adipocyte differentiation.

  16. Delta(9)-tetrahydrocannabinol inhibits 17beta-estradiol-induced proliferation and fails to activate androgen and estrogen receptors in MCF7 human breast cancer cells.

    Science.gov (United States)

    von Bueren, A O; Schlumpf, M; Lichtensteiger, W

    2008-01-01

    Delta(9)-tetrahydrocannabinol (THC) exerts palliative effects in cancer patients, but produces adverse effects on the endocrine and reproductive systems. Experimental evidence concerning such effects is controversial. Whether THC exhibits estrogenic or androgenic activity in vitro was investigated. Estrogenic effects of THC were analyzed in vitro by measuring the proliferation of estrogen-sensitive MCF7 cells. Androgenic activity was investigated by the A-Screen assay that measures androgen-dependent inhibition of proliferation of the androgen receptor (AR)-positive human mammary carcinoma cell line, MCF7-AR1. In contrast to 17beta-estradiol, included as positive control with an EC50 value (concentration required for 50% of maximal 17beta-estradiol-induced proliferation) of 1.00 x 10(-12) M, THC failed to induce cell proliferation in the MCF7 cell line at concentrations between 10(-13) and 10(-4) M. THC inhibited 17beta-estradiol-induced proliferation in wild-type MCF7 and MCF7-AR1 cells, with an IC50 value of 2.6 x 10(-5) M and 9 x 10(-6) M, respectively. THC failed to act as an estrogen, but antagonized 17beta-estradiol-induced proliferation. This effect was independent of the AR expression level.

  17. Reciprocal upregulation of scavenger receptors complicates interpretation of nanoparticle uptake in non-phagocytic cells

    NARCIS (Netherlands)

    Prapainop, Kanlaya; Miao, Rong; Åberg, Christoffer; Salvati, Anna; Dawson, Kenneth A

    2017-01-01

    Nanoparticles have great potential as drug delivery vehicles or as imaging agents for treatment and diagnosis of various diseases. It is therefore crucial to understand how nanoparticles are taken up by cells, both phagocytic and non-phagocytic. Small interference RNA has previously been used to

  18. Effect of ligand activation of peroxisome proliferator-activated receptor-β/δ (PPARβ/δ) in human lung cancer cell lines

    International Nuclear Information System (INIS)

    He Pengfei; Borland, Michael G.; Zhu Bokai; Sharma, Arun K.; Amin, Shantu; El-Bayoumy, Karam; Gonzalez, Frank J.; Peters, Jeffrey M.

    2008-01-01

    There is compelling evidence that peroxisome proliferator-activated receptor-β/δ (PPARβ/δ) mediates terminal differentiation and is associated with inhibition of cell growth. However, it was recently suggested that growth of two human lung cancer cell lines is enhanced by PPARβ/δ. The goal of the present study was to provide insight in resolving this controversy. Therefore, the effect of ligand activation of PPARβ/δ in A549 and H1838 human lung cancer cell lines was examined using two high affinity PPARβ/δ ligands. Ligand activation of PPARβ/δ caused up-regulation of a known PPARβ/δ target gene, angiopoietin-like 4 (Angptl4) but did not influence expression of phosphatase and tensin homolog (PTEN) or phosphorylation of protein kinase B (Akt), and did not affect cell growth. Results from this study demonstrate that two human lung cancer cell lines respond to ligand activation of PPARβ/δ by modulation of target gene expression (Angptl4), but fail to exhibit significant modulation of cell proliferation

  19. Peroxisome Proliferator-Activated Receptor γ Regulates the Expression of Lipid Phosphate Phosphohydrolase 1 in Human Vascular Endothelial Cells

    Directory of Open Access Journals (Sweden)

    Yazi Huang

    2014-01-01

    Full Text Available Lipid phosphate phosphohydrolase 1 (LPP1, a membrane ectophosphohydrolase regulating the availability of bioactive lipid phosphates, plays important roles in cellular signaling and physiological processes such as angiogenesis and endothelial migration. However, the regulated expression of LPP1 remains largely unknown. Here, we aimed to examine a role of peroxisome proliferator-activated receptor γ (PPARγ in the transcriptional control of LPP1 gene expression. In human umbilical vein endothelial cells (HUVECs, quantitative reverse transcriptase polymerase chain reaction (qRT-PCR demonstrated that activation of PPARγ increased the mRNA level of LPP1. Chromatin immunoprecipitation assay showed that PPARγ binds to the putative PPAR-responsive elements (PPREs within the 5′-flanking region of the human LPP1 gene. Genomic fragment containing 1.7-kilobase of the promoter region was cloned by using PCR. The luciferase reporter assays demonstrated that overexpression of PPARγ and rosiglitazone, a specific ligand for PPARγ, could significantly upregulate the reporter activity. However, site-directed mutagenesis of the PPRE motif abolished the induction. In conclusion, our results demonstrated that PPARγ transcriptionally activated the expression of LPP1 gene in ECs, suggesting a potential role of PPARγ in the metabolism of phospholipids.

  20. Novel time-dependent vascular actions of Δ9-tetrahydrocannabinol mediated by peroxisome proliferator-activated receptor gamma

    International Nuclear Information System (INIS)

    O'Sullivan, Saoirse E.; Tarling, Elizabeth J.; Bennett, Andrew J.; Kendall, David A.; Randall, Michael D.

    2005-01-01

    Cannabinoids have widespread effects on the cardiovascular system, only some of which are mediated via G-protein-coupled cell surface receptors. The active ingredient of cannabis, Δ 9 -tetrahydrocannabinol (THC), causes acute vasorelaxation in various arteries. Here we show for the first time that THC also causes slowly developing vasorelaxation through activation of peroxisome proliferator-activated receptors gamma (PPARγ). In vitro, THC (10 μM) caused time-dependent vasorelaxation of rat isolated arteries. Time-dependent vasorelaxation to THC was similar to that produced by the PPARγ agonist rosiglitazone and was inhibited by the PPARγ antagonist GW9662 (1 μM), but not the cannabinoid CB 1 receptor antagonist AM251 (1 μM). Time-dependent vasorelaxation to THC requires an intact endothelium, nitric oxide, production of hydrogen peroxide, and de novo protein synthesis. In transactivation assays in cultured HEK293 cells, THC-activated PPARγ, transiently expressed in combination with retinoid X receptor α and a luciferase reporter gene, in a concentration-dependent manner (100 nM-10 μM). In vitro incubation with THC (1 or 10 μM, 8 days) stimulated adipocyte differentiation in cultured 3T3L1 cells, a well-accepted property of PPARγ ligands. The present results provide strong evidence that THC is a PPARγ ligand, stimulation of which causes time-dependent vasorelaxation, implying some of the pleiotropic effects of cannabis may be mediated by nuclear receptors

  1. Assessment of chitosan-affected metabolic response by peroxisome proliferator-activated receptor bioluminescent imaging-guided transcriptomic analysis.

    Directory of Open Access Journals (Sweden)

    Chia-Hung Kao

    Full Text Available Chitosan has been widely used in food industry as a weight-loss aid and a cholesterol-lowering agent. Previous studies have shown that chitosan affects metabolic responses and contributes to anti-diabetic, hypocholesteremic, and blood glucose-lowering effects; however, the in vivo targeting sites and mechanisms of chitosan remain to be clarified. In this study, we constructed transgenic mice, which carried the luciferase genes driven by peroxisome proliferator-activated receptor (PPAR, a key regulator of fatty acid and glucose metabolism. Bioluminescent imaging of PPAR transgenic mice was applied to report the organs that chitosan acted on, and gene expression profiles of chitosan-targeted organs were further analyzed to elucidate the mechanisms of chitosan. Bioluminescent imaging showed that constitutive PPAR activities were detected in brain and gastrointestinal tract. Administration of chitosan significantly activated the PPAR activities in brain and stomach. Microarray analysis of brain and stomach showed that several pathways involved in lipid and glucose metabolism were regulated by chitosan. Moreover, the expression levels of metabolism-associated genes like apolipoprotein B (apoB and ghrelin genes were down-regulated by chitosan. In conclusion, these findings suggested the feasibility of PPAR bioluminescent imaging-guided transcriptomic analysis on the evaluation of chitosan-affected metabolic responses in vivo. Moreover, we newly identified that downregulated expression of apoB and ghrelin genes were novel mechanisms for chitosan-affected metabolic responses in vivo.

  2. A specific primed immune response in Drosophila is dependent on phagocytes.

    Directory of Open Access Journals (Sweden)

    Linh N Pham

    2007-03-01

    Full Text Available Drosophila melanogaster, like other invertebrates, relies solely on its innate immune response to fight invading microbes; by definition, innate immunity lacks adaptive characteristics. However, we show here that priming Drosophila with a sublethal dose of Streptococcus pneumoniae protects against an otherwise-lethal second challenge of S. pneumoniae. This protective effect exhibits coarse specificity for S. pneumoniae and persists for the life of the fly. Although not all microbial challenges induced this specific primed response, we find that a similar specific protection can be elicited by Beauveria bassiana, a natural fly pathogen. To characterize this primed response, we focused on S. pneumoniae-induced protection. The mechanism underlying this protective effect requires phagocytes and the Toll pathway. However, activation of the Toll pathway is not sufficient for priming-induced protection. This work contradicts the paradigm that insect immune responses cannot adapt and will promote the search for similar responses overlooked in organisms with an adaptive immune response.

  3. The atherogenic bacterium Porphyromonas gingivalis evades circulating phagocytes by adhering to erythrocytes

    DEFF Research Database (Denmark)

    Belstrøm, Daniel; Holmstrup, Palle; Damgaard, Christian

    2011-01-01

    A relationship between periodontitis and coronary heart disease has been investigated intensively. A pathogenic role for the oral bacterium Porphyromonas gingivalis has been suggested for both diseases. We examined whether complement activation by P. gingivalis strain ATCC 33277 allows...... the bacterium to adhere to human red blood cells (RBCs) and thereby evade attack by circulating phagocytes. On incubation with normal human serum, the P. gingivalis strain efficiently fixed complement component 3 (C3). Incubation of bacteria with washed whole blood cells suspended in autologous serum resulted...... in a dose- and time-dependent adherence to RBCs. The adherence required functionally intact complement receptor 1 (CR1; also called CD35) on the RBCs and significantly inhibited the uptake of P. gingivalis by neutrophils and B cells within 1 min of incubation (by 64% and 51%, respectively...

  4. Discovery of peroxisome proliferator-activated receptor α (PPARα) activators with a ligand-screening system using a human PPARα-expressing cell line.

    Science.gov (United States)

    Tachibana, Keisuke; Yuzuriha, Tomohiro; Tabata, Ryotaro; Fukuda, Syohei; Maegawa, Takashi; Takahashi, Rika; Tanimoto, Keiichi; Tsujino, Hirofumi; Nunomura, Kazuto; Lin, Bangzhong; Matsuura, Yoshiharu; Tanaka, Toshiya; Hamakubo, Takao; Sakai, Juro Js; Kodama, Tatsuhiko; Kobayashi, Tadayuki; Ishimoto, Kenji; Miyachi, Hiroyuki; Doi, Takefumi

    2018-05-15

    Peroxisome proliferator-activated receptor alpha (PPARα) is a ligand-activated transcription factor that belongs to the superfamily of nuclear hormone receptors. PPARα is mainly expressed in the liver, where it activates fatty acid oxidation and lipoprotein metabolism and improves plasma lipid profiles. Therefore, PPARα activators are often used to treat patients with dyslipidemia. To discover additional PPARα activators as potential compounds for use in hypolipidemic drugs, here we established human hepatoblastoma cell lines with luciferase reporter expression from the promoters containing peroxisome proliferator responsive elements (PPRE) and tetracycline-regulated expression of full-length human PPARα to quantify the effects of chemical ligands on PPARα activity. Using the established cell-based PPARα-activator screening system to screen a library of > 12,000 chemical compounds, we identified several hit compounds with basic chemical skeletons different from those of known PPARα agonists. One of the hit compounds, a 1H-pyrazolo[3,4-b]pyridine-4-carboxylic acid derivative we termed compound 3, selectively up-regulated PPARα transcriptional activity, leading to PPARα target gene expression both in vitro and in vivo. Of note, the half-maximal effective concentrations of the hit compounds were lower than that of the known PPARα ligand fenofibrate. Finally, fenofibrate or compound 3 treatment of high fructose-fed rats having elevated plasma triglyceride levels for 14 days indicated that compound 3 reduces plasma triglyceride levels with similar efficiency as fenofibrate. These observations raise the possibility that 1H-pyrazolo[3,4-b]pyridine-4-carboxylic acid derivatives might be effective drug candidates for selective targeting of PPARα to manage dyslipidemia. Published under license by The American Society for Biochemistry and Molecular Biology, Inc.

  5. Stromal COX-2 signaling activated by deoxycholic acid mediates proliferation and invasiveness of colorectal epithelial cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Yingting, E-mail: yitizhu@yahoo.com [Arizona Cancer Center, The University of Arizona, Tucson, AZ 85724 (United States); Tissue Tech Inc., Miami, FL 33173 (United States); Zhu, Min; Lance, Peter [Arizona Cancer Center, The University of Arizona, Tucson, AZ 85724 (United States)

    2012-08-31

    Highlights: Black-Right-Pointing-Pointer Human colonic cancer associated fibroblasts are major sources of COX-2 and PGE{sub 2}. Black-Right-Pointing-Pointer The fibroblasts interact with human colonic epithelial cancer cells. Black-Right-Pointing-Pointer Activation of COX-2 signaling in the fibroblasts affects behavior of the epithelia. Black-Right-Pointing-Pointer Protein Kinase C controls the activation of COX-2 signaling. -- Abstract: COX-2 is a major regulator implicated in colonic cancer. However, how COX-2 signaling affects colonic carcinogenesis at cellular level is not clear. In this article, we investigated whether activation of COX-2 signaling by deoxycholic acid (DCA) in primary human normal and cancer associated fibroblasts play a significant role in regulation of proliferation and invasiveness of colonic epithelial cancer cells. Our results demonstrated while COX-2 signaling can be activated by DCA in both normal and cancer associated fibroblasts, the level of activation of COX-2 signaling is significantly greater in cancer associated fibroblasts than that in normal fibroblasts. In addition, we discovered that the proliferative and invasive potential of colonic epithelial cancer cells were much greater when the cells were co-cultured with cancer associated fibroblasts pre-treated with DCA than with normal fibroblasts pre-treated with DCA. Moreover, COX-2 siRNA attenuated the proliferative and invasive effect of both normal and cancer associate fibroblasts pre-treated with DCA on the colonic cancer cells. Further studies indicated that the activation of COX-2 signaling by DCA is through protein kinase C signaling. We speculate that activation of COX-2 signaling especially in cancer associated fibroblasts promotes progression of colonic cancer.

  6. Stromal COX-2 signaling activated by deoxycholic acid mediates proliferation and invasiveness of colorectal epithelial cancer cells

    International Nuclear Information System (INIS)

    Zhu, Yingting; Zhu, Min; Lance, Peter

    2012-01-01

    Highlights: ► Human colonic cancer associated fibroblasts are major sources of COX-2 and PGE 2 . ► The fibroblasts interact with human colonic epithelial cancer cells. ► Activation of COX-2 signaling in the fibroblasts affects behavior of the epithelia. ► Protein Kinase C controls the activation of COX-2 signaling. -- Abstract: COX-2 is a major regulator implicated in colonic cancer. However, how COX-2 signaling affects colonic carcinogenesis at cellular level is not clear. In this article, we investigated whether activation of COX-2 signaling by deoxycholic acid (DCA) in primary human normal and cancer associated fibroblasts play a significant role in regulation of proliferation and invasiveness of colonic epithelial cancer cells. Our results demonstrated while COX-2 signaling can be activated by DCA in both normal and cancer associated fibroblasts, the level of activation of COX-2 signaling is significantly greater in cancer associated fibroblasts than that in normal fibroblasts. In addition, we discovered that the proliferative and invasive potential of colonic epithelial cancer cells were much greater when the cells were co-cultured with cancer associated fibroblasts pre-treated with DCA than with normal fibroblasts pre-treated with DCA. Moreover, COX-2 siRNA attenuated the proliferative and invasive effect of both normal and cancer associate fibroblasts pre-treated with DCA on the colonic cancer cells. Further studies indicated that the activation of COX-2 signaling by DCA is through protein kinase C signaling. We speculate that activation of COX-2 signaling especially in cancer associated fibroblasts promotes progression of colonic cancer.

  7. Ghrelin augments murine T-cell proliferation by activation of the phosphatidylinositol-3-kinase, extracellular signal-regulated kinase and protein kinase C signaling pathways

    Science.gov (United States)

    Lee, Jun Ho; Patel, Kalpesh; Tae, Hyun Jin; Lustig, Ana; Kim, Jie Wan; Mattson, Mark P.; Taub, Dennis D.

    2014-01-01

    Thymic atrophy occurs during normal aging, and is accelerated by exposure to chronic stressors that elevate glucocorticoid levelsand impair the naïve T cell output. The orexigenic hormone ghrelin was recently shown to attenuate age-associated thymic atrophy. Here, we report that ghrelin enhances the proliferation of murine CD4+ primary T cells and a CD4+ T-cell line. Ghrelin induced activation of the ERK1/2 and Akt signaling pathways, via upstream activation of phosphatidylinositol-3-kinase and protein kinase C, to enhance T-cell proliferation. Moreover, ghrelin induced expression of the cell cycle proteins cyclin D1, cyclin E, cyclin-dependent kinase 2 (CDK2) and retinoblastoma phosphorylation. Finally, ghrelin activated the above-mentioned signaling pathways and stimulated thymocyte proliferation in young and older mice in vivo. PMID:25447526

  8. FoxP3 inhibits proliferation and induces apoptosis of gastric cancer cells by activating the apoptotic signaling pathway

    International Nuclear Information System (INIS)

    Ma, Gui-Fen; Chen, Shi-Yao; Sun, Zhi-Rong; Miao, Qing; Liu, Yi-Mei; Zeng, Xiao-Qing; Luo, Tian-Cheng; Ma, Li-Li; Lian, Jing-Jing; Song, Dong-Li

    2013-01-01

    Highlights: ► The article revealed FoxP3 gene function in gastric cancer firstly. ► Present the novel roles of FoxP3 in inhibiting proliferation and promoting apoptosis in gastric cancer cells. ► Overexpression of FoxP3 increased proapoptotic molecules and repressed antiapoptotic molecules. ► Silencing of FoxP3 reduced the expression of proapoptotic genes, such as PARP, caspase-3 and caspase-9. ► FoxP3 is sufficient for activating the apoptotic signaling pathway. -- Abstract: Forkhead Box Protein 3 (FoxP3) was identified as a key transcription factor to the occurring and function of the regulatory T cells (Tregs). However, limited evidence indicated its function in tumor cells. To elucidate the precise roles and underlying molecular mechanism of FoxP3 in gastric cancer (GC), we examined the expression of FoxP3 and the consequences of interfering with FoxP3 gene in human GC cell lines, AGS and MKN45, by multiple cellular and molecular approaches, such as immunofluorescence, gene transfection, CCK-8 assay, clone formation assay, TUNEL assay, Flow cytometry, immunoassay and quantities polymerase chain reaction (PCR). As a result, FoxP3 was expressed both in nucleus and cytoplasm of GC cells. Up-regulation of FoxP3 inhibited cell proliferation and promoted cell apoptosis. Overexpression of FoxP3 increased the protein and mRNA levels of proapoptotic molecules, such as poly ADP-ribose polymerase1 (PARP), caspase-3 and caspase-9, and repressed the expression of antiapoptotic molecules, such as cellular inhibitor of apoptosis-1 (c-IAP1) and the long isoform of B cell leukemia/lymphoma-2 (Bcl-2). Furthermore, silencing of FoxP3 by siRNA in GC cells reduced the expression of proapoptotic genes, such as PARP, caspase-3 and caspase-9. Collectively, our findings identify the novel roles of FoxP3 in inhibiting proliferation and inducing apoptosis in GC cells by regulating apoptotic signaling, which could be a promising therapeutic approach for gastric cancer.

  9. FoxP3 inhibits proliferation and induces apoptosis of gastric cancer cells by activating the apoptotic signaling pathway

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Gui-Fen [Department of Gastroenterology, Zhongshan Hospital, Fudan University, Shanghai (China); Chen, Shi-Yao, E-mail: shiyao_chen@163.com [Department of Gastroenterology, Zhongshan Hospital, Fudan University, Shanghai (China); Endoscopy Center, Zhongshan Hospital, Fudan University, Shanghai (China); Sun, Zhi-Rong [Department of Anesthesiology, Cancer Center, Fudan University, Shanghai (China); Miao, Qing; Liu, Yi-Mei; Zeng, Xiao-Qing; Luo, Tian-Cheng [Department of Gastroenterology, Zhongshan Hospital, Fudan University, Shanghai (China); Ma, Li-Li; Lian, Jing-Jing [Endoscopy Center, Zhongshan Hospital, Fudan University, Shanghai (China); Song, Dong-Li [Biomedical Research Center, Zhongshan Hospital, Fudan University, Shanghai (China)

    2013-01-11

    Highlights: Black-Right-Pointing-Pointer The article revealed FoxP3 gene function in gastric cancer firstly. Black-Right-Pointing-Pointer Present the novel roles of FoxP3 in inhibiting proliferation and promoting apoptosis in gastric cancer cells. Black-Right-Pointing-Pointer Overexpression of FoxP3 increased proapoptotic molecules and repressed antiapoptotic molecules. Black-Right-Pointing-Pointer Silencing of FoxP3 reduced the expression of proapoptotic genes, such as PARP, caspase-3 and caspase-9. Black-Right-Pointing-Pointer FoxP3 is sufficient for activating the apoptotic signaling pathway. -- Abstract: Forkhead Box Protein 3 (FoxP3) was identified as a key transcription factor to the occurring and function of the regulatory T cells (Tregs). However, limited evidence indicated its function in tumor cells. To elucidate the precise roles and underlying molecular mechanism of FoxP3 in gastric cancer (GC), we examined the expression of FoxP3 and the consequences of interfering with FoxP3 gene in human GC cell lines, AGS and MKN45, by multiple cellular and molecular approaches, such as immunofluorescence, gene transfection, CCK-8 assay, clone formation assay, TUNEL assay, Flow cytometry, immunoassay and quantities polymerase chain reaction (PCR). As a result, FoxP3 was expressed both in nucleus and cytoplasm of GC cells. Up-regulation of FoxP3 inhibited cell proliferation and promoted cell apoptosis. Overexpression of FoxP3 increased the protein and mRNA levels of proapoptotic molecules, such as poly ADP-ribose polymerase1 (PARP), caspase-3 and caspase-9, and repressed the expression of antiapoptotic molecules, such as cellular inhibitor of apoptosis-1 (c-IAP1) and the long isoform of B cell leukemia/lymphoma-2 (Bcl-2). Furthermore, silencing of FoxP3 by siRNA in GC cells reduced the expression of proapoptotic genes, such as PARP, caspase-3 and caspase-9. Collectively, our findings identify the novel roles of FoxP3 in inhibiting proliferation and inducing apoptosis

  10. Knockdown of Pokemon protein expression inhibits hepatocellular carcinoma cell proliferation by suppression of AKT activity.

    Science.gov (United States)

    Zhu, Xiaosan; Dai, Yichen; Chen, Zhangxin; Xie, Junpei; Zeng, Wei; Lin, Yuanyuan

    2013-01-01

    Overexpression of Pokemon, which is an erythroid myeloid ontogenic factor protein, occurs in different cancers, including hepatocellular carcinoma (HCC). Pokemon is also reported to have an oncogenic activity in various human cancers. This study investigated the effect of Pokemon knockdown on the regulation of HCC growth. POK shRNA suppressed the expression of Pokemon protein in HepG2 cells compared to the negative control vector-transfected HCC cells. Pokemon knockdown also reduced HCC cell viability and enhanced cisplatin-induced apoptosis in HCC cells. AKT activation and the expression of various cell cycle-related genes were inhibited following Pokemon knockdown. These data demonstrate that Pokemon may play a role in HCC progression, suggesting that inhibition of Pokemon expression using Pokemon shRNA should be further evaluated as a novel target for the control of HCC.

  11. "Proliferation of cytotoxic and activated T cells during acute Epstein-Barr virus induced Infectious Mononucleosis "

    Directory of Open Access Journals (Sweden)

    Mansoori SD

    2002-05-01

    Full Text Available The immune responses that develop following Epstien-Barr Virus (EBV infection are complex and involve both humoral and to a greater extent cell-mediated immune mechanisms. To evaluate the immune response, flow cytometric analysis of the peripheral blood of six patients during the acute phase of EBV infection was performed. This analysis revealed a significant increase in the percentages and the absolute number of CD8+cytotoxic and activated (HLA-DR+ - T lymphocytes and in some cases with a concomitan decrease in the percentages of B (CD19+ lymphocytes and T helper (CD4+ lymphocytes. These patient invariably had inverted CD4/CD8 ratio. All changes reversed to normal level during the recovery phase of infection. It is therefore concluded that EBV specific cytotoxic and activated T lymphocytes are essential in controlling acute EBV infection presented by the infected B cells.

  12. Activation of β-Adrenoceptors by Dobutamine May Induce a Higher Expression of Peroxisome Proliferator-Activated Receptors δ (PPARδ in Neonatal Rat Cardiomyocytes

    Directory of Open Access Journals (Sweden)

    Ming-Ting Chou

    2012-01-01

    Full Text Available Recent evidence showed the role of peroxisome proliferator-activated receptors (PPARs in cardiac function. Cardiac contraction induced by various agents is critical in restoring the activity of peroxisome proliferator-activated receptors δ (PPARδ in cardiac myopathy. Because dobutamine is an agent widely used to treat heart failure in emergency setting, this study is aimed to investigate the change of PPARδ in response to dobutamine. Neonatal rat cardiomyocytes were used to examine the effects of dobutamine on PPARδ expression levels and cardiac troponin I (cTnI phosphorylation via Western blotting analysis. We show that treatment with dobutamine increased PPARδ expression and cTnI phosphorylation in a time- and dose-dependent manner in neonatal rat cardiomyocytes. These increases were blocked by the antagonist of β1-adrenoceptors. Also, the action of dobutamine was related to the increase of calcium ions and diminished by chelating intracellular calcium. Additionally, dobutamine-induced action was reduced by the inhibition of downstream messengers involved in this calcium-related pathway. Moreover, deletion of PPARδ using siRNA generated the reduction of cTnI phosphorylation in cardiomyocytes treated with dobutamine. Thus, we concluded that PPARδ is increased by dobutamine in cardiac cells.

  13. PI3K/Akt Activated by GPR30 and Src Regulates 17β-Estradiol-Induced Cultured Immature Boar Sertoli Cells Proliferation.

    Science.gov (United States)

    Yang, Wei-Rong; Zhu, Feng-Wei; Zhang, Jiao-Jiao; Wang, Yi; Zhang, Jia-Hua; Lu, Cheng; Wang, Xian-Zhong

    2016-05-24

    Sertoli cell (SC) is a key element in the process of spermatogenesis. Accumulating research show that estrogen plays an important role in regulating boar SC proliferation. However, it is unclear whether phosphatidylinositol-4,5-bisphosphate 3-kinase/protein kinase B (PI3K/Akt) is involved in this process. In the present study, the role of PI3K/Akt on the 17β-estradiol-induced piglet SC proliferation was explored. In addition, we also explained the roles of G-protein-coupled estrogen receptor (GPR30) and Sarcoma protein (Src) in this process. Our study demonstrated that, 17β-estradiol induced activation of PI3K in a time-dependent manner. Both G-15 (an antagonist of GPR30, 0.1 μmol/L) and PP2 (an inhibitor of Src, 2.0 μmol/L) inhibited 17β-estradiol-induced activation of PI3K, reduced SC proliferation, and decreased messenger RNA (mRNA) and protein expression of S-phase kinase-associated protein 2 (Skp2). We also found that 17β-estradiol induced activation of Akt in a time-dependent manner. Both LY294002 (an inhibitor of PI3K) and 10-DEBC (an inhibitor of Akt) significantly reduced 17β-estradiol-induced SC proliferation and reduced mRNA and protein expression of Skp2. In addition, LY294002 inhibited 17β-estradiol-induced activation of Akt. The results indicated that 17β-estradiol regulates SC proliferation by activating PI3K/Akt. Both GPR30 and Src are involved in 17β-estradiol-induced phosphorylation of PI3K/Akt. Activation of PI3K/Akt enhances the expression of Skp2, which promotes SC proliferation. © The Author(s) 2016.

  14. DEPDC1 promotes cell proliferation and tumor growth via activation of E2F signaling in prostate cancer.

    Science.gov (United States)

    Huang, Lin; Chen, Keng; Cai, Zhao-Peng; Chen, Fu-Chao; Shen, Hui-Yong; Zhao, Wei-Hua; Yang, Song-Jie; Chen, Xu-Biao; Tang, Guo-Xue; Lin, Xi

    2017-08-26

    DEP domain containing 1 (DEPDC1) is recently reported to be overexpressed in several types of human cancer; however the role of DEPDC1 in prostate cancer remains to be investigated. Herein, we identified that the DEPDC1 mRNA and protein expression levels were dramatically increased in prostate cancer tissues and cell lines. Overexpression of DEPDC1 promoted, but depletion of DEPDC1 inhibited cell proliferation by regulating the G1-S phase cell cycle transition. Importantly, we found that DEPDC1 was essential for the tumor growth and formation of bone metastases of prostate cancer cells in vivo. Finally, we demonstrated that DEPDC1 interacted with E2F1 and increased its transcriptional activity, leading to hyper-activation of E2F signaling in prostate cancer cells. Our findings reveal an oncogenic role of DEPDC1 in prostate cancer progression via activation of E2F signaling, and suggest DEPDC1 might be a potential therapeutic target against the disease. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. Efficacy of peroxisome proliferator activated receptor agonist in the treatment of virus-associated haemophagocytic syndrome in a rabbit model.

    Science.gov (United States)

    Hsieh, Wen-Chuan; Lan, Bau-Shin; Chen, Yi-Ling; Chang, Yao; Chuang, Huai-Chia; Su, Ih-Jen

    2010-01-01

    Virus-associated haemophagocytic syndrome (VAHS) is a fatal complication of viral infections, such as Epstein-Barr virus and H5N1 influenza, that results from macrophage activation and pro inflammatory cytokine injuries. The high comorbidity and mortality of current therapy urgently demands an ideal agent based on VAHS pathogenesis. Peroxisome proliferator activated receptor (PPAR) agonists, regulators of metabolic syndrome, can exhibit immunomodulatory effects on macrophage activation and cytokine secretion. In this study, we adopted rosiglitazone, a PPAR-gamma agonist, for VAHS control in a Herpesvirus papio (HVP)-infected rabbit model. Various doses of rosiglitazone were orally administered to rabbits on day 7 or day 20 after intravenous challenge with 5 x 10(7) copies of HVP. The rabbits that received 4 mg/day rosiglitazone had significantly increased survival when treated at an early stage of infection (P<0.01), whereas a higher dose (8 mg/day) was required at the advanced stage of the disease (P<0.05). All rosiglitazone-treated rabbits had significantly improved laboratory parameters and plasma tumour necrosis factor-alpha levels. Importantly, rosiglitazone could also inhibit viral replication in vitro and in vivo. PPAR agonists could represent a potentially new agent for the therapy of VAHS.

  16. Peroxisomal proliferator activated receptor-γ deficiency in a Canadian kindred with familial partial lipodystrophy type 3 (FPLD3

    Directory of Open Access Journals (Sweden)

    Cao Henian

    2006-01-01

    Full Text Available Abstract Background Familial partial lipodystrophy (Dunnigan type 3 (FPLD3, Mendelian Inheritance in Man [MIM] 604367 results from heterozygous mutations in PPARG encoding peroxisomal proliferator-activated receptor-γ. Both dominant-negative and haploinsufficiency mechanisms have been suggested for this condition. Methods We present a Canadian FPLD3 kindred with an affected mother who had loss of fat on arms and legs, but no increase in facial, neck, suprascapular or abdominal fat. She had profound insulin resistance, diabetes, severe hypertriglyceridemia and relapsing pancreatitis, while her pre-pubescent daughter had normal fat distribution but elevated plasma triglycerides and C-peptide and depressed high-density lipoprotein cholesterol. Results The mother and daughter were each heterozygous for PPARG nonsense mutation Y355X, whose protein product in vitro was transcriptionally inactive with no dominant-negative activity against the wild-type receptor. In addition the mutant protein appeared to be markedly unstable. Conclusion Taken together with previous studies of human PPARG mutations, these findings suggest that PPAR-γ deficiency due either to haploinsufficiency or to substantial activity loss due to dominant negative interference of the normal allele product's function can each contribute to the FPLD3 phenotype.

  17. In Vitro and in Vivo Anticancer Activity of Pardaxin against Proliferation and Growth of Oral Squamous Cell Carcinoma

    Directory of Open Access Journals (Sweden)

    Yifan Han

    2015-12-01

    Full Text Available Pardaxin (H-GFFALIPKIISSPLFKTLLSAVGSALSSSGGQE-OH, a 33-amino-acid polypeptide, is an antimicrobial peptide (AMP isolated from the marine fish species Pardachirus marmoratus. Pardaxin shows antibacterial and antitumor activities. However, pardaxin-induced inhibition of oral cancer and the mechanism of tumor reduction in buccal pouch carcinogenesis after pardaxin painting remain undetermined. Additionally, the toxic effects of pardaxin on normal tissue remain unclear. The present study investigated the anticancer activity of pardaxin in oral squamous cell carcinoma (OSCC cells in the hamster buccal pouch model with or without 7,12-dimethylbenz[a]anthracene (DMBA pretreatment. This is the first study to confirm the effects of pardaxin on normal tissue and its nontoxic effects in vivo. Cell viability assays and colony formation tests in OSCC cell lines (SCC-4 demonstrated that pardaxin reduced cell viability in a dose-dependent manner. Immunofluorescence staining of cleaved caspase-3 in SCC-4 cells revealed that expression of activated caspase-3 in SCC-4 cells significantly increased after 24-h treatment with pardaxin. Additionally, a cell cycle analysis indicated that pardaxin treatment resulted in the cell cycle arrest of SCC-4 cells in the G2/M phase, thereby limiting cell proliferation. Furthermore, pardaxin treatment substantially alleviated carcinogenesis in the DMBA-induced hamster buccal pouch model by lowering prostaglandin E2 levels. These results suggest that pardaxin is a potential marine drug for adjuvant chemotherapy for human OSCC and oral cancer.

  18. Platelet-released growth factors can accelerate tenocyte proliferation and activate the anti-oxidant response element.

    Science.gov (United States)

    Tohidnezhad, M; Varoga, D; Wruck, C J; Brandenburg, L O; Seekamp, A; Shakibaei, M; Sönmez, T T; Pufe, Thomas; Lippross, S

    2011-05-01

    Little is know about the pathophysiology of acute and degenerative tendon injuries. Although most lesions are uncomplicated, treatment is long and unsatisfactory in a considerable number of cases. Besides the common growth factors that were shown to be relevant for tendon integrity more recently protection against oxidative stress was shown to promote tendon healing. To improve tendon regeneration, many have advocated the use of platelet-rich plasma (PRP), a thrombocyte concentrate that can serve as an autologous source of growth factors. In this study, we investigated the effect of platelet-released growth factors (PRGF) on tenocytes. Tenocytes were isolated from the Achilles tendon of postnatal rats. Tenocyte cell cultures were stimulated with PRGF. We used a CyQuant assay and WST assay to analyse tendon cell growth and viability in different concentrations of PRGF. Migration and proliferation of cells grown in PRGF were assessed by a scratch test. A dual-luciferase assay was used to demonstrate the activation of the anti-oxidant response element (ARE) in tenocytes. A positive effect of PRGF could be shown on tendon cell growth and migratory capacity. PRGF activated the Nrf2-ARE pathway in a dose-dependent manner. Here, we provide evidence of a biological effect of PRGF on tenocytes by the promotion of tenocyte growth and activation of the Nrf2-ARE pathway. This is a novel aspect of the action of platelet concentrates on tendon growth.

  19. Fenofibrate, a peroxisome proliferator-activated receptor α ligand, prevents abnormal liver function induced by a fasting–refeeding process

    International Nuclear Information System (INIS)

    Lee, Joon No; Dutta, Raghbendra Kumar; Kim, Seul-Gi; Lim, Jae-Young; Kim, Se-Jin; Choe, Seong-Kyu; Yoo, Kyeong-Won; Song, Seung Ryel; Park, Do-Sim; So, Hong-Seob; Park, Raekil

    2013-01-01

    Highlights: •A fasting–refeeding high fat diet (HDF) model mimics irregular eating habit. •A fasting–refeeding HFD induces liver ballooning injury. •A fasting–refeeding HDF process elicits hepatic triglyceride accumulation. •Fenofibrate, PPARα ligand, prevents liver damage induced by refeeding HFD. -- Abstract: Fenofibrate, a peroxisome proliferator-activated receptor α (PPARα) agonist, is an anti-hyperlipidemic agent that has been widely used in the treatment of dyslipidemia. In this study, we examined the effect of fenofibrate on liver damage caused by refeeding a high-fat diet (HFD) in mice after 24 h fasting. Here, we showed that refeeding HFD after fasting causes liver damage in mice determined by liver morphology and liver cell death. A detailed analysis revealed that hepatic lipid droplet formation is enhanced and triglyceride levels in liver are increased by refeeding HFD after starvation for 24 h. Also, NF-κB is activated and consequently induces the expression of TNF-α, IL1-β, COX-2, and NOS2. However, treating with fenofibrate attenuates the liver damage and triglyceride accumulation caused by the fasting–refeeding HFD process. Fenofibrate reduces the expression of NF-κB target genes but induces genes for peroxisomal fatty acid oxidation, peroxisome biogenesis and mitochondrial fatty acid oxidation. These results strongly suggest that the treatment of fenofibrate ameliorates the liver damage induced by fasting–refeeding HFD, possibly through the activation of fatty acid oxidation

  20. Fenofibrate, a peroxisome proliferator-activated receptor α ligand, prevents abnormal liver function induced by a fasting–refeeding process

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Joon No; Dutta, Raghbendra Kumar; Kim, Seul-Gi; Lim, Jae-Young; Kim, Se-Jin; Choe, Seong-Kyu [Center for Metabolic Function Regulation, and Department of Microbiology, School of Medicine, Wonkwang University, Iksan (Korea, Republic of); Yoo, Kyeong-Won [Center for Metabolic Function Regulation, and Department of Microbiology, School of Medicine, Wonkwang University, Iksan (Korea, Republic of); Immune-network Pioneer Research Center, Department of Biochemistry, College of Medicine, Dong-A University, Busan (Korea, Republic of); Song, Seung Ryel [Center for Metabolic Function Regulation, and Department of Microbiology, School of Medicine, Wonkwang University, Iksan (Korea, Republic of); Park, Do-Sim [Center for Metabolic Function Regulation, and Department of Microbiology, School of Medicine, Wonkwang University, Iksan (Korea, Republic of); Department of Laboratory of Medicine, School of Medicine, Wonkwang University, Iksan (Korea, Republic of); So, Hong-Seob [Center for Metabolic Function Regulation, and Department of Microbiology, School of Medicine, Wonkwang University, Iksan (Korea, Republic of); Park, Raekil [Center for Metabolic Function Regulation, and Department of Microbiology, School of Medicine, Wonkwang University, Iksan (Korea, Republic of)

    2013-12-06

    Highlights: •A fasting–refeeding high fat diet (HDF) model mimics irregular eating habit. •A fasting–refeeding HFD induces liver ballooning injury. •A fasting–refeeding HDF process elicits hepatic triglyceride accumulation. •Fenofibrate, PPARα ligand, prevents liver damage induced by refeeding HFD. -- Abstract: Fenofibrate, a peroxisome proliferator-activated receptor α (PPARα) agonist, is an anti-hyperlipidemic agent that has been widely used in the treatment of dyslipidemia. In this study, we examined the effect of fenofibrate on liver damage caused by refeeding a high-fat diet (HFD) in mice after 24 h fasting. Here, we showed that refeeding HFD after fasting causes liver damage in mice determined by liver morphology and liver cell death. A detailed analysis revealed that hepatic lipid droplet formation is enhanced and triglyceride levels in liver are increased by refeeding HFD after starvation for 24 h. Also, NF-κB is activated and consequently induces the expression of TNF-α, IL1-β, COX-2, and NOS2. However, treating with fenofibrate attenuates the liver damage and triglyceride accumulation caused by the fasting–refeeding HFD process. Fenofibrate reduces the expression of NF-κB target genes but induces genes for peroxisomal fatty acid oxidation, peroxisome biogenesis and mitochondrial fatty acid oxidation. These results strongly suggest that the treatment of fenofibrate ameliorates the liver damage induced by fasting–refeeding HFD, possibly through the activation of fatty acid oxidation.

  1. Rhododenol and raspberry ketone impair the normal proliferation of melanocytes through reactive oxygen species-dependent activation of GADD45.

    Science.gov (United States)

    Kim, Minjeong; Baek, Heung Soo; Lee, Miri; Park, Hyeonji; Shin, Song Seok; Choi, Dal Woong; Lim, Kyung-Min

    2016-04-01

    Rhododenol or rhododendrol (RD, 4-(4-hydroxyphenyl)-2-butanol) occurs naturally in many plants along with raspberry ketone (RK, 4-(4-hydroxyphenyl)-2-butanone), a ketone derivative, which include Nikko maple tree (Acer nikoense) and white birch (Betula platyphylla). De-pigmenting activity of RD was discovered and it was used as a brightening ingredient for the skin whitening cosmetics. Recently, cosmetics containing RD were withdrawn from the market because a number of consumers developed leukoderma, inflammation and erythema on their face, neck and hands. Here, we explored the mechanism underlying the toxicity of RD and RK against melanocytes using B16F10 murine melanoma cells and human primary epidermal melanocytes. Treatment with RD or RK resulted in the decreased cell viability in a dose-dependent manner which appeared from cell growth arrest. Consistently, ROS generation was significantly increased by RD or RK as determined by DCF-enhanced fluorescence. An antioxidant enzyme, glutathione peroxidase was depleted as well. In line with ROS generation, oxidative damages and the arrest of normal cell proliferation, GADD genes (Growth Arrest and DNA Damage) that include GADD45 and GADD153, were significantly up-regulated. Prevention of ROS generation with an anti-oxidant, N-acetylcysteine (NAC) significantly rescued RD and RK-suppressed melanocyte proliferation. Consistently, up-regulation of GADD45 and GADD153 was significantly attenuated by NAC, suggesting that increased ROS and the resultant growth arrest of melanocytes may contribute to RD and RK-induced leukoderma. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Epigenetic activation of SIN1 promotes NSCLC cell proliferation and metastasis by affecting the epithelial–mesenchymal transition

    International Nuclear Information System (INIS)

    Hu, Zhongwu; Wang, Yaqin; Wang, Yuemei; Zang, Bao; Hui, Hongxia; You, Zhenbing; Wang, Xiaowei

    2017-01-01

    Stress-activated protein kinase (SAPK) interacting protein 1 (SIN1) is an essential component of mTORC2. Previous studies have shown that SIN1 is a key regulator of Akt pathway which plays an important role in various pathological conditions including cancer. While its effects and mechanisms on the progression of NSCLC remain unknown. In this study, we report that SIN1 is able to promote the growth and migration of NSCLC cells both in vitro and in vivo. Overexpression of SIN1 promoted A549 and H1299 cells proliferation by both MTT and colony formation assays. Consistently, knockdown of SIN1 inhibited the proliferation of these cells. In transwell assay, overexpression of SIN1 increased the migration of A549 and H1299 cells, while SIN1 knockdown reduced their migration. In a tumor xenograft model, overexpression of SIN1 promoted tumor growth of A549 cells in vivo, while SIN1 knockdown suppresses the tumor growth. We also found a mechanistic link between SIN1 and H3K4me3, H3K4me3 is involved in SIN1 upregulation. Moreover, SIN1 can significantly promote the in vitro migration and invasion of NSCLC cells via induction epithelial mesenchymal transition (EMT) process, which subsequently leads to transcriptional downregulation of epithelial marker E-cadherin and upregulation of mesenchymal markers N-cadherin and Vimentin expression. Together, our results reveal that SIN1 plays an important role in NSCLC and SIN1 is a potential biomarker and a promising target in the treatment of NSCLC.

  3. Genomewide analyses define different modes of transcriptional regulation by peroxisome proliferator-activated receptor-β/δ (PPARβ/δ.

    Directory of Open Access Journals (Sweden)

    Till Adhikary

    Full Text Available Peroxisome proliferator-activated receptors (PPARs are nuclear receptors with essential functions in lipid, glucose and energy homeostasis, cell differentiation, inflammation and metabolic disorders, and represent important drug targets. PPARs heterodimerize with retinoid X receptors (RXRs and can form transcriptional activator or repressor complexes at specific DNA elements (PPREs. It is believed that the decision between repression and activation is generally governed by a ligand-mediated switch. We have performed genomewide analyses of agonist-treated and PPARβ/δ-depleted human myofibroblasts to test this hypothesis and to identify global principles of PPARβ/δ-mediated gene regulation. Chromatin immunoprecipitation sequencing (ChIP-Seq of PPARβ/δ, H3K4me3 and RNA polymerase II enrichment sites combined with transcriptional profiling enabled the definition of 112 bona fide PPARβ/δ target genes showing either of three distinct types of transcriptional response: (I ligand-independent repression by PPARβ/δ; (II ligand-induced activation and/or derepression by PPARβ/δ; and (III ligand-independent activation by PPARβ/δ. These data identify PPRE-mediated repression as a major mechanism of transcriptional regulation by PPARβ/δ, but, unexpectedly, also show that only a subset of repressed genes are activated by a ligand-mediated switch. Our results also suggest that the type of transcriptional response by a given target gene is connected to the structure of its associated PPRE(s and the biological function of its encoded protein. These observations have important implications for understanding the regulatory PPAR network and PPARβ/δ ligand-based drugs.

  4. Protease-activated receptor-1 negatively regulates proliferation of neural stem/progenitor cells derived from the hippocampal dentate gyrus of the adult mouse

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    Masayuki Tanaka

    2016-07-01

    Full Text Available Thrombin-activated protease-activated receptor (PAR-1 regulates the proliferation of neural cells following brain injury. To elucidate the involvement of PAR-1 in the neurogenesis that occurs in the adult hippocampus, we examined whether PAR-1 regulated the proliferation of neural stem/progenitor cells (NPCs derived from the murine hippocampal dentate gyrus. NPC cultures expressed PAR-1 protein and mRNA encoding all subtypes of PAR. Direct exposure of the cells to thrombin dramatically attenuated the cell proliferation without causing cell damage. This thrombin-induced attenuation was almost completely abolished by the PAR antagonist RWJ 56110, as well as by dabigatran and 4-(2-aminoethylbenzenesulfonyl fluoride (AEBSF, which are selective and non-selective thrombin inhibitors, respectively. Expectedly, the PAR-1 agonist peptide (AP SFLLR-NH2 also attenuated the cell proliferation. The cell proliferation was not affected by the PAR-1 negative control peptide RLLFT-NH2, which is an inactive peptide for PAR-1. Independently, we determined the effect of in vivo treatment with AEBSF or AP on hippocampal neurogenesis in the adult mouse. The administration of AEBSF, but not that of AP, significantly increased the number of newly-generated cells in the hippocampal subgranular zone. These data suggest that PAR-1 negatively regulated adult neurogenesis in the hippocampus by inhibiting the proliferative activity of the NPCs.

  5. Peroxisome proliferator-activated receptor δ inhibits Porphyromonas gingivalis lipopolysaccharide-induced activation of matrix metalloproteinase-2 by downregulating NADPH oxidase 4 in human gingival fibroblasts.

    Science.gov (United States)

    Yoo, T; Ham, S