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Sample records for alpha inhibits prostaglandin

  1. Tumor necrosis factor alpha inhibits in vitro bovine embryo development through a prostaglandin mediated mechanism

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    Jackson Lauren R

    2012-03-01

    Full Text Available Abstract Mastitis or other infectious diseases have been related to reduced fertility in cattle. Inflammatory cytokines such as tumor necrosis factor α (TNFα are released in response to infection and may have negative effects on embryo development. In the current study the effect of exposure to TNFα on the development of in vitro fertilized bovine embryos was examined. Indomethacin, a prostaglandin synthesis inhibitor, was used to determine if blockade of prostaglandin synthesis would alter the effects of TNFα. Ovaries were obtained from a local abattoir and immature COC were isolated from 2-10 mm follicles, in vitro matured and fertilized. After fertilization, groups of presumptive zygotes were randomly placed into either control development medium, medium containing 25 ng/mL TNFα or medium containing 25 ng/mL TNFα plus 1 μg/mL indomethacin. The proportion of blastocysts formed was assessed at day 7 of culture. Fewer embryos exposed to TNFα alone reached the blastocyst stage (17.5 ± 2.4%, P

  2. Interleukin 1. alpha. inhibits prostaglandin E sub 2 release to suppress pulsatile release of luteinizing hormone but not follicle-stimulating hormone

    Energy Technology Data Exchange (ETDEWEB)

    Rettori, V.; McCann, S.M. (Univ. of Texas Southwestern Medical Center, Dallas (United States)); Gimeno, M.F. (CEFYBO, Buenos Aires (Argentina)); Karara, A. (Vanderbilt Univ., Nashville, TN (United States)); Gonzalez, M.C. (Univ. de La Laguno, Tenerife (Spain))

    1991-04-01

    Interleukin 1{alpha} (IL-1{alpha}), a powerful endogenous pyrogen released from monocytes and macrophages by bacterial endotoxin, stimulates corticotropin, prolactin, and somatotropin release and inhibits thyrotropin release by hypothalamic action. The authors injected recombinant human IL-1{alpha} into the third cerebral ventricle, to study its effect on the pulsatile release of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) in conscious, freely moving, ovariectomized rats. Intraventricular injection of 0.25 pmol of IL-1{alpha} caused an almost immediate reduction of plasma LH concentration. To determine the mechanism of the suppression of LH release, mediobasal hypothalamic fragments were incubated in vitro with IL-1{alpha} (10 pM) and the release of LH-releasing hormone (LHRH) and prostaglandin E{sub 2} into the medium was measured by RIA in the presence or absence of nonrepinephrine. 1{alpha} reduced basal LHRH release and blocked LHRH release induced by nonrepinephrine. In conclusion, IL-1{alpha} suppresses LH but not FSH release by an almost complete cessation of pulsatile release of LH in the castrated rat. The mechanism of this effect appears to be by inhibition of prostaglandin E{sub 2}-mediated release of LHRH.

  3. Acetylsalicylic acid regulates MMP-2 activity and inhibits colorectal invasion of murine B16F0 melanoma cells in C57BL/6J mice: effects of prostaglandin F(2)alpha.

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    Tsai, Chin-Shaw Stella; Luo, Shue-Fen; Ning, Chung-Chu; Lin, Chien-Liang; Jiang, Ming-Chung; Liao, Ching-Fong

    2009-08-01

    Epidemiological studies indicate that acetylsalicylic acid may reduce the risk of mortality due to colon cancers. Metastasis is the major cause of cancer death. Matrix metalloproteinases (MMPs) play important roles in tumor invasion regulation, and prostaglandin F(2)alpha (PGF(2)alpha) is a key stimulator of MMP production. Thus, we investigated whether acetylsalicylic acid regulated MMP activity and the invasion of cancer cells and whether PGF(2)alpha attenuated acetylsalicylic acid-inhibited invasion of cancer cells. Gelatin-based zymography assays showed that acetylsalicylic acid inhibited the MMP-2 activity of B16F0 melanoma cells. Matrigel-based chemoinvasion assays showed that acetylsalicylic acid inhibited the invasion of B16F0 cells. Acetylsalicylic acid can inhibit PGF(2)alpha synthesis and PGF(2)alpha is a key stimulator of MMP-2 production. Our data showed that PGF(2)alpha treatment attenuated the acetylsalicylic acid-inhibited invasion of B16F0 cells. In animal experiments, acetylsalicylic acid reduced colorectal metastasis of B16F0 cells in C57BL/6J mice by 44%. Our results suggest that PGF(2)alpha is a therapeutic target for metastasis inhibition and acetylsalicylic acid may possess anti-metastasis ability.

  4. Prostaglandin F2alpha elevates blood pressure and promotes atherosclerosis

    DEFF Research Database (Denmark)

    Yu, Ying; Lucitt, Margaret B; Stubbe, Jane

    2009-01-01

    Little is known about prostaglandin F(2alpha) in cardiovascular homeostasis. Prostaglandin F(2alpha) dose-dependently elevates blood pressure in WT mice via activation of the F prostanoid (FP) receptor. The FP is expressed in preglomerular arterioles, renal collecting ducts, and the hypothalamus....

  5. Many Putative Endocrine Disruptors Inhibit Prostaglandin Synthesis

    DEFF Research Database (Denmark)

    Kristensen, David M.; Skalkam, Maria L.; Audouze, Karine Marie Laure

    2011-01-01

    Background: Prostaglandins (PGs) play key roles in development and maintenance of homeostasis of the adult body. Despite these important roles, it remains unclear whether the PG pathway is a target for endocrine disruption. However, several known endocrine disrupting compounds (EDCs) share a high...... of endocrine disruption. Results: We found that many known EDCs inhibit the PG pathway in a mouse Sertoli cell line and in human primary mast cells. The EDCs also reduced PG synthesis in ex vivo rat testis and it was correlated with a reduced testosterone production. The inhibition of PG synthesis occurs...

  6. Prostaglandin E1 and prostaglandin F2 alpha in exudate in nickel allergy

    DEFF Research Database (Denmark)

    Lerche, A; Bisgaard, H; Kassis, V;

    1989-01-01

    with and one without nickel challenge. A higher flux of leukocytes, PGE1 and PGF2 alpha was observed during the second day of allergen exposure, while the concentrations probably due to dilution were unchanged or diminished, indicating an unspecific role of the prostaglandins during the contact allergic...

  7. Prostaglandins in human semen during fish oil ingestion: evidence for in vivo cyclooxygenase inhibition and appearance of novel trienoic compounds.

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    Knapp, H R

    1990-04-01

    Marine oils may offer cardiovascular benefits, but inhibition of prostaglandin E and prostaglandin F synthesis by fish oil has been found in animal studies, and such effects could alter physiological responses in man to a clinically significant degree. Since greater amounts of E and F-type prostaglandins are made in human seminal vesicles than in the rest of the body combined, the influence of n-3 supplements upon semen prostaglandins was assessed in 10 subjects before and after one month of taking 50 ml menhaden oil daily. Prostaglandins E1, E2 and their 19-hydroxy derivatives were measured by HPLC-UV as PGB's, and prostaglandin E3, 19-OH PGE3, and analogous PGF's by gas chromatography/mass spectrometry. Fish oil ingestion reduced concentrations of one- and two series prostaglandins (mean reduction in PGE's = 37%, in PGF's = 20%, p less than 0.05), while more than doubling the low amounts of PGE3 and PGF3 alpha, and their previously undescribed 19-hydroxy derivatives. Semen phospholipids were enriched in eicosapentaenoic acid after dietary fish oil, but sperm counts and motility were not altered during the study. Since dietary fish oil reduces prostaglandin concentration in semen, clinical trials of n-3 fatty acids should also evaluate other possible results of in vivo cyclooxygenase inhibition.

  8. Transport of prostaglandin F(2alpha) pulses from the uterus to the ovary at the time of luteolysis in ruminants is regulated by prostaglandin transporter-mediated mechanisms.

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    Lee, JeHoon; McCracken, John A; Banu, Sakhila K; Rodriguez, Royce; Nithy, Thamizh K; Arosh, Joe A

    2010-07-01

    In ruminants, prostaglandin F2alpha (PGF(2alpha)) is the uterine luteolytic hormone. During luteolysis, PGF(2alpha) is synthesized and released from the endometrium in a pulsatile pattern. The unique structure of the vascular utero-ovarian plexus (UOP) allows transport of luteolytic PGF(2alpha) pulses directly from the uterus to the ovary, thus bypassing the systemic circulation. However, the underlying molecular mechanism is not known. The objective of the present study was to determine a role for PG transporter protein (PGT) in the compartmental transport of PGF(2alpha) from uterus to ovary through the UOP at the time of luteolysis using the sheep as a ruminant model. [(3)H]PGF(2alpha), with or without a PGT inhibitor, was infused into UOP, and PGF(2alpha) transport and PGT protein expression were determined. Results indicate that PGT protein is expressed in tunica intima, tunica media, and tunica adventitia of the utero-ovarian vein and the ovarian artery of the UOP, and the expression levels are higher on d 10-15 compared with d 3-6 of the estrous cycle. Pharmacological inhibition of PGT prevented transport of exogenous [(3)H]PGF(2alpha) as well as oxytocin-induced endogenous luteolytic PGF(2alpha) pulse up to 80% from uterine venous blood into ovarian arterial blood through the UOP at the time of luteolysis in sheep. Taken together, these results indicate that at the time of luteolysis, transport of PGF(2alpha) from uterus to ovary through the UOP is regulated by PGT-mediated mechanisms. These findings also suggest that impaired PGT-mediated transport of PGF(2alpha) from the utero-ovarian vein into the ovarian artery could adversely influence luteolysis and thus affect fertility in ruminants.

  9. Curcumin blocks prostaglandin E2 biosynthesis through direct inhibition of the microsomal prostaglandin E2 synthase-1.

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    Koeberle, Andreas; Northoff, Hinnak; Werz, Oliver

    2009-08-01

    Prostaglandin E(2) (PGE(2)) plays a crucial role in the apparent link between tumor growth and chronic inflammation. Cyclooxygenase (COX)-2 and microsomal PGE(2) synthase-1, which are overexpressed in many cancers, are functionally coupled and thus produce massive PGE(2) in various tumors. Curcumin, a polyphenolic beta-diketone from tumeric with anti-carcinogenic and anti-inflammatory activities, was shown to suppress PGE(2) formation and to block the expression of COX-2 and of microsomal PGE(2) synthase-1. Here, we identified microsomal PGE(2) synthase-1 as a molecular target of curcumin and we show that inhibition of microsomal PGE(2) synthase-1 activity is the predominant mechanism of curcumin to suppress PGE(2) biosynthesis. Curcumin reversibly inhibited the conversion of PGH(2) to PGE(2) by microsomal PGE(2) synthase-1 in microsomes of interleukin-1beta-stimulated A549 lung carcinoma cells with an IC(50) of 0.2 to 0.3 micromol/L. Closely related polyphenols (e.g., resveratrol, coniferyl alcohol, eugenol, rosmarinic acid) failed in this respect, and isolated ovine COX-1 and human recombinant COX-2 were not inhibited by curcumin up to 30 micromol/L. In lipopolysaccharide-stimulated human whole blood, curcumin inhibited COX-2-derived PGE(2) formation from endogenous or from exogenous arachidonic acid, whereas the concomitant formation of COX-2-mediated 6-keto PGF(1)alpha and COX-1-derived 12(S)-hydroxy-5-cis-8,10-trans-heptadecatrienoic acid was suppressed only at significant higher concentrations. Based on the key function of PGE(2) in inflammation and carcinogenesis, inhibition of microsomal PGE(2) synthase-1 by curcumin provides a molecular basis for its anticarcinogenic and anti-inflammatory activities.

  10. Circadian variations of prostaglandin E2 and F2 alpha release in the golden hamster retina.

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    de Zavalía, Nuria; Fernandez, Diego C; Sande, Pablo H; Keller Sarmiento, María I; Golombek, Diego A; Rosenstein, Ruth E; Silberman, Dafne M

    2010-02-01

    Circadian variations of prostaglandin E2 and F2alpha release were examined in the golden hamster retina. Both parameters showed significant diurnal variations with maximal values at midnight. When hamsters were placed under constant darkness for 48 h, the differences in prostaglandin release between subjective mid-day and subjective midnight persisted. Western blot analysis showed that cyclooxygenase (COX)-1 levels were significantly higher at midnight than at mid-day, and at subjective midnight than at subjective mid-day, whereas no changes in COX-2 levels were observed among these time points. Immunohistochemical studies indicated the presence of COX-1 and COX-2 in the inner (but not outer) retina. Circadian variations of retinal prostaglandin release were also assessed in suprachiasmatic nuclei (SCN)-lesioned animals. Significant differences in retinal prostaglandin release between subjective mid-day and subjective midnight were observed in SCN-lesioned animals. These results indicate that hamster retinal prostaglandin release is regulated by a retinal circadian clock independent from the SCN. Thus, the present results suggest that the prostaglandin/COX-1 system could be a retinal clock output or part of the retinal clock mechanism.

  11. Prostaglandin E2 induces hypoxia-inducible factor-1alpha stabilization and nuclear localization in a human prostate cancer cell line.

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    Liu, Xin Hua; Kirschenbaum, Alexander; Lu, Min; Yao, Shen; Dosoretz, Amy; Holland, James F; Levine, Alice C

    2002-12-20

    Hypoxia-induced up-regulation of vascular endothelial growth factor (VEGF) expression is a critical event leading to tumor neovascularization. Hypoxia stimulates hypoxia-inducible factor-1alpha (HIF-1alpha), a transcriptional activator of VEGF. Cyclooxygenase (COX)-2, an inducible enzyme that catalyzes the formation of prostaglandins (PGs) from arachidonic acid, is also induced by hypoxia. We reported previously that COX-2 inhibition prevents hypoxic up-regulation of VEGF in human prostate cancer cells and that prostaglandin E(2) (PGE(2)) restores hypoxic effects on VEGF. We hypothesized that PGE(2) mediates hypoxic effects on VEGF by modulating HIF-1alpha expression. Addition of PGE(2) to PC-3ML human prostate cancer cells had no effect on HIF-1alpha mRNA levels. However, PGE(2) significantly increased HIF-1alpha protein levels, particularly in the nucleus. This effect of PGE(2) largely results from the promotion of HIF-1alpha translocation from the cytosol to the nucleus. PGE(2) addition to PC-3 ML cells transfected with a GFP-HIF-1alpha vector induced a time-dependent nuclear accumulation of the HIF-1alpha protein. Two selective COX-2 inhibitors, meloxicam and NS398, decreased HIF-1alpha levels and nuclear localization, under both normoxic and hypoxic conditions. Of several prostaglandins tested, only PGE(2) reversed the effects of a COX-2 inhibitor in hypoxic cells. Finally, PGE(2) effects on HIF-1alpha were specifically inhibited by PD98059 (a MAPK inhibitor). These data demonstrate that PGE(2) production via COX-2-catalyzed pathway plays a critical role in HIF-1alpha regulation by hypoxia and imply that COX-2 inhibitors can prevent hypoxic induction of HIF-mediated gene transcription in cancer cells.

  12. [Cardiovascular effect of 15(S)-15-methyl-prostaglandin F2alpha].

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    Retzke, U; Schwarz, R

    1978-01-01

    The reaction of the cardiovascular system on one intramuscular injection of 250 microgram 15-methyl-prostaglandin F2alpha was examined in 14 normotensive healthy pregnant women between 7th and 11th weeks of gestation with the method of quantitative sphygmometry with unbloody graphic recording of arterial blood pressure and direct electronic determination of velocity of aortic pulse wave. The tests were done in 10 patients in intervals of 5 minutes for one hour and in 4 subjects for 12 hours in intervals of one hour. Systolic blood pressure remains nearly constant, but diastolic blood pressure increases and then decreases significantly. Heart rate decreases significantly. Aortic pulse wave velocity decreases in a characteristic manner. Analogous to the biphasic behaviour of blood pressure cardiac output decreases significantly, but then increases insignificantly. The inverse changes of total peripheral resistance are insignificant. Comparing these reactions with the cardiovascular effects of prostaglandin F2alpha or E2, 15-methyl-prostaglandin F2alpha shows the smallest circulatory alterations.

  13. Cellular mechanisms by which oxytocin mediates uterine prostaglandin F2 alpha synthesis in bovine endometrium: role of calcium.

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    Burns, P D; Hayes, S H; Silvia, W J

    1998-11-01

    The objective of these experiments was to determine the role of Ca2+ during oxytocin-stimulated prostaglandin (PG) F2 alpha release from bovine endometrial tissue in vitro. Uteri were collected from dairy cows on the day after spontaneous luteal regression. Caruncular endometrial explants were dissected and incubated in vitro to determine phospholipase C activity or PGF2 alpha release. A23,187 (a calcium ionophore) and maitotoxin (an activator of voltage-gated L-type calcium channels) stimulated release of PGF 2 alpha in a concentration-dependent manner (P < 0.05). Thapsigargin (induces accumulation of Ca2+ in the cytoplasm by inhibiting endoplasmic reticulum Ca2+/ATPase pumps) stimulated release of PGF2 alpha in a concentration-dependent manner as well (P < 0.13). Oxytocin (10(-6) M), AIF4- (a nonspecific activator of G-proteins; 10(-5) M), A23,187 (10(-5) M), and melittin (a stimulator of phospholipase A2; 10(-4) M) stimulated PGF2 alpha release when explants were incubated in Ca(2+)-free medium (P < 0.10); however, oxytocin, A23,187, or melittin were unable to stimulate PGF2 alpha release when explants were incubated in Ca(2+)-free medium containing the calcium chelator EGTA (P < 0.10). This treatment did not prevent oxytocin or AIF4- from stimulating phospholipase C activity (P < 0.08). CoCl2 (a nonspecific Ca2+ channel blocker) and methoxyverapamil (a specific voltage-gated L-type Ca2+ channel blocker) prevented oxytocin from stimulating PGF2 alpha release (P < 0.05). Our results suggest that both extracellular and intracellular Ca2+ may be required for oxytocin to stimulate PGF2 alpha secretion in bovine endometrial tissue.

  14. Prostaglandin F2 alpha-induced response of the bovine ovary, oviduct (uterine tube), and uterus.

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    Singh, L P; Sadiku, A; Verma, O P

    1979-12-01

    Tissue strips from the ovary, (uterine tube), and oviduct, and uterus of pregnant and nonpregnant cows were tested for their contractile response to prostaglandin F2 alpha (PGF2 alpha). When 2.1 x 10(-6)M PGF2 alpha was added to the uterine strips, tension of tissues from pregnant cows increased sharply; however, tension in tissues from nonpregnant cows only increased moderately. Similar concentrations failed to elicit any response from oviductal tissues of either group. Unlike the uterus and the oviduct, the ovaries contracted slowly and irregularly. They responded with varying degrees of stimulation; ovaries from pregnant cows with brief and mild stimulation and ovaries from nonpregnant cows with slower and relatively stronger stimulation. Results indicate that the bovine ovary contracts rhythmically and that its sensitivity to PGF2 alpha decreases during pregnancy in contrast to the bovine uterus which becomes increasingly sensitive during pregnancy.

  15. [The inhibition of prostaglandin induced uterine contractions by diazoxide in vitro (author's transl)].

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    Schneider-Affeld, F; Rüttgers, H; Hter, J; Kubli, F

    1977-02-01

    The tocolytic efficiency of Diazoxide, a benzothiadiazine derivative with pronounced musculotropic action, was tested on the isolated uteri of non-gravid and gravid rats. Regular uterine contractions were induced by the prostaglandines E2 and F2 alpha. Their amplitude and frequency could be suppressed totally or subtotally. Contraction intervals lasted 4--22 min. The basal tone was reduced in most cases.

  16. Induction of parturition in swine with prostaglandin F(2)alpha, estradiol benzoate and oxytocin.

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    Gall, M A; Day, B N

    1987-03-01

    Pregnant sows and gilts were administered either 0, 2.5, 5, 10 or 20 mg prostaglandin F(2)alpha (PGF(2)alpha) intramuscularly on Day 112 or 113 of gestation at 0800 h in an effort to induce parturition. The average interval from PGF(2)alpha injection to farrowing was 55.1 +/- 5.7, 29.4 +/- 3.1, 32.1 +/- 4.6, 27.8 +/- 1.8 and 26.9 +/- 1.1 h for 0, 2.5, 5, 10 and 20 mg, respectively. All PGF(2)alpha treatments increased (P gestation length was significantly shorter in treated gilts; however, no detrimental effect on pig performance or pig survivability was observed. A second trial evaluated the effect of a 10-mg dose of PGF(2)alpha on the induction of parturition in sows in order to obtain a majority of sows farrowing within normal working hours (0700 to 1700 h). The interval from injection to farrowing was decreased (P < 0.05) by PGF(2)alpha treatment (66.2 +/- 5.3 vs 28.1 +/- 2.2 h). Fifty-seven percent (P < 0.05) of PGF(2)alpha-treated sows farrowed between 0700 and 1700 h as compared to 13.6% for control sows. A third trial was conducted to examine a sequential treatment of PGF(2)alpha and oxytocin to control the time of parturition more precisely. Sows receiving only 10 mg of PGF(2)alpha farrowed on an average 31.1 +/- 1.4 h after injection. The injection of 40 IU oxytocin 24 to 28 h after PGF(2)alpha decreased (P < 0.05) the interval from PGF(2)alpha to farrowing (28.1 +/- 0.9 h). The addition of oxytocin increased (P < 0.05) the number of sows farrowing within 3 h of injection (33 vs 86% for PGF(2)alpha and PGF(2)alpha + oxytocin treatments, respectively). A fourth trial was designed to determine if the addition of exogenous estradiol benzoate (EB) to a sequential treatment of PGF(2)alpha and oxytocin would improve the predictability and synchronization of the induced parturition. Sows were assigned to receive either saline, 10 mg PGF(2)alpha + 40 IU oxytocin or 10 mg PGF(2)alpha + 5 mg EB + 40 IU oxytocin. The addition of EB reduced (P < 0.01) the variance in

  17. TISSUE REGENERATION. Inhibition of the prostaglandin-degrading enzyme 15-PGDH potentiates tissue regeneration.

    Science.gov (United States)

    Zhang, Yongyou; Desai, Amar; Yang, Sung Yeun; Bae, Ki Beom; Antczak, Monika I; Fink, Stephen P; Tiwari, Shruti; Willis, Joseph E; Williams, Noelle S; Dawson, Dawn M; Wald, David; Chen, Wei-Dong; Wang, Zhenghe; Kasturi, Lakshmi; Larusch, Gretchen A; He, Lucy; Cominelli, Fabio; Di Martino, Luca; Djuric, Zora; Milne, Ginger L; Chance, Mark; Sanabria, Juan; Dealwis, Chris; Mikkola, Debra; Naidoo, Jacinth; Wei, Shuguang; Tai, Hsin-Hsiung; Gerson, Stanton L; Ready, Joseph M; Posner, Bruce; Willson, James K V; Markowitz, Sanford D

    2015-06-12

    Agents that promote tissue regeneration could be beneficial in a variety of clinical settings, such as stimulating recovery of the hematopoietic system after bone marrow transplantation. Prostaglandin PGE2, a lipid signaling molecule that supports expansion of several types of tissue stem cells, is a candidate therapeutic target for promoting tissue regeneration in vivo. Here, we show that inhibition of 15-hydroxyprostaglandin dehydrogenase (15-PGDH), a prostaglandin-degrading enzyme, potentiates tissue regeneration in multiple organs in mice. In a chemical screen, we identify a small-molecule inhibitor of 15-PGDH (SW033291) that increases prostaglandin PGE2 levels in bone marrow and other tissues. SW033291 accelerates hematopoietic recovery in mice receiving a bone marrow transplant. The same compound also promotes tissue regeneration in mouse models of colon and liver injury. Tissues from 15-PGDH knockout mice demonstrate similar increased regenerative capacity. Thus, 15-PGDH inhibition may be a valuable therapeutic strategy for tissue regeneration in diverse clinical contexts.

  18. 15-Deoxy-Delta(12,14)-prostaglandin-J(2) reveals a new pVHL-independent, lysosomal-dependent mechanism of HIF-1alpha degradation.

    Science.gov (United States)

    Olmos, Gemma; Arenas, María I; Bienes, Raquel; Calzada, María Jose; Aragonés, Julián; Garcia-Bermejo, Maria Laura; Landazuri, Manuel O; Lucio-Cazaña, Javier

    2009-07-01

    Hypoxia-inducible factor-1alpha (HIF-1alpha) protein is degraded under normoxia by its association to von Hippel-Lindau protein (pVHL) and further proteasomal digestion. However, human renal cells HK-2 treated with 15-deoxy-Delta(12,14)-prostaglandin-J(2) (15d-PGJ(2)) accumulate HIF-1alpha in normoxic conditions. Thus, we aimed to investigate the mechanism involved in this accumulation. We found that 15d-PGJ(2) induced an over-accumulation of HIF-1alpha in RCC4 cells, which lack pVHL and in HK-2 cells treated with inhibitors of the pVHL-proteasome pathway. These results indicated that pVHL-proteasome-independent mechanisms are involved, and therefore we aimed to ascertain them. We have identified a new lysosomal-dependent mechanism of HIF-1alpha degradation as a target for 15d-PGJ(2) based on: (1) HIF-1alpha colocalized with the specific lysosomal marker Lamp-2a, (2) 15d-PGJ(2) inhibited the activity of cathepsin B, a lysosomal protease, and (3) inhibition of lysosomal activity did not result in over-accumulation of HIF-1alpha in 15d-PGJ(2)-treated cells. Therefore, expression of HIF-1alpha is also modulated by lysosomal degradation.

  19. Prostaglandin F2-alpha receptor (FPr expression on porcine corpus luteum microvascular endothelial cells (pCL-MVECs

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    Forni Monica

    2007-07-01

    Full Text Available Abstract Background The corpus luteum (CL is a transient endocrine gland and prostaglandin F2-alpha is considered to be the principal luteolysin in pigs. In this species, the in vivo administration of prostaglandin F2-alpha induces apoptosis in large vessels as early as 6 hours after administration. The presence of the prostaglandin F2-alpha receptor (FPr on the microvascular endothelial cells (pCL-MVECs of the porcine corpus luteum has not yet been defined. The aim of the study was to assess FPr expression in pCL-MVECs in the early and mid-luteal phases (EL-p, ML-p, and during pregnancy (P-p. Moreover, the effectiveness of prostaglandin F2-alpha treatment in inducing pCL-MVEC apoptosis was tested. Methods Porcine CLs were collected in the EL and ML phases and during P-p. All CLs from each animal were minced together and the homogenates underwent enzymatic digestion. The pCL-MVECs were then positively selected by an immunomagnetic separation protocol using Dynabeads coated with anti-CD31 monoclonal antibody and seeded in flasks in the presence of EGM 2-MV (Microvascular Endothelial Cell Medium-2. After 4 days of culture, the cells underwent additional immunomagnetic selection and were seeded in flasks until the confluent stage. PCR Real time, western blot and immunodetection assays were utilized to assess the presence of FPr on pCL-MVEC primary cultures. Furthermore, the influence of culture time (freshly isolated, cultured overnight and at confluence and hormonal treatment (P4 and E2 on FPr expression in pCL-MVECs was also investigated. Apoptosis was detected by TUNEL assay of pCL-MVECs exposed to prostaglandin F2-alpha. Results We obtained primary cultures of pCL-MVECs from all animals. FPr mRNA and protein levels showed the highest value (ANOVA in CL-MVECs derived from the early-luteal phase. Moreover, freshly isolated MVECs showed a higher FPr mRNA value than those cultured overnight and confluent cells (ANOVA. prostaglandin F2-alpha

  20. [Inhibition of prostaglandin synthesis during the therapy of nephrogenic diabetes insipidus].

    Science.gov (United States)

    Stögmann, W; Bohrn, E

    1984-01-06

    A report is presented of a male infant with nephrogenic diabetes insipidus type I. A low-solute-load diet and large fluid intake were not able to prevent hypertonic dehydration and to control the disease. It responded within 3 days to indomethacin (3 mg/kg body weight), a prostaglandin synthetase inhibitor. The boy is doing well on this regimen and no side-effects have been observed after 2 years of treatment. Hitherto only a few case reports have been published on this therapeutic regimen, but all confirm the high efficacy of prostaglandin synthesis inhibition as the treatment of choice in nephrogenic diabetes insipidus.

  1. Inhibition of the Prostaglandin Transporter PGT Lowers Blood Pressure in Hypertensive Rats and Mice.

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    Yuling Chi

    Full Text Available Inhibiting the synthesis of endogenous prostaglandins with nonsteroidal anti-inflammatory drugs exacerbates arterial hypertension. We hypothesized that the converse, i.e., raising the level of endogenous prostaglandins, might have anti-hypertensive effects. To accomplish this, we focused on inhibiting the prostaglandin transporter PGT (SLCO2A1, which is the obligatory first step in the inactivation of several common PGs. We first examined the role of PGT in controlling arterial blood pressure blood pressure using anesthetized rats. The high-affinity PGT inhibitor T26A sensitized the ability of exogenous PGE2 to lower blood pressure, confirming both inhibition of PGT by T26A and the vasodepressor action of PGE2 T26A administered alone to anesthetized rats dose-dependently lowered blood pressure, and did so to a greater degree in spontaneously hypertensive rats than in Wistar-Kyoto control rats. In mice, T26A added chronically to the drinking water increased the urinary excretion and plasma concentration of PGE2 over several days, confirming that T26A is orally active in antagonizing PGT. T26A given orally to hypertensive mice normalized blood pressure. T26A increased urinary sodium excretion in mice and, when added to the medium bathing isolated mouse aortas, T26A increased the net release of PGE2 induced by arachidonic acid, inhibited serotonin-induced vasoconstriction, and potentiated vasodilation induced by exogenous PGE2. We conclude that pharmacologically inhibiting PGT-mediated prostaglandin metabolism lowers blood pressure, probably by prostaglandin-induced natriuresis and vasodilation. PGT is a novel therapeutic target for treating hypertension.

  2. Dietary (n-3)-fatty acids, prostaglandins, and prolonged gestation in humans

    DEFF Research Database (Denmark)

    Hansen, Harald S.; Olsen, S.F.

    1988-01-01

    Prostaglandins, especially prostaglandin F2 alpha, are important regulators in the onset and maintenance of parturition in humans. Inhibition of prostaglandin formation by drugs can prolong gestation in humans. High dietary intake of long chain (n-3)-fatty acids can inhibit formation of many...... arachidonic acid-derived prostaglandins as well as stimulate formation of eicosapentaenoic acid-derived prostaglandins. The latter ones often have lower biological activity than the former ones. The effect of (n-3)-fatty acids on prostaglandin formation has been shown by analysis of prostaglandin metabolites...... in human urine. Very little is known about the tissue origin as well as the physiologicalfunctions of those prostaglandins, the metabolites of which are quantitated in urine from non-pregnant humans. In pregnant women the increased amount of prostaglandin F2 alpha-metabolites in urine, plasma and amniotic...

  3. Activity of phospholipase C and release of prostaglandin F2 alpha by endometrial tissue from ovariectomized ewes receiving progesterone and estradiol.

    Science.gov (United States)

    Raw, R E; Silvia, W J

    1991-03-01

    Progesterone and estradiol interact to regulate secretion of prostaglandin (PG) F2 alpha from the ovine endometrium in response to oxytocin. Two experiments were conducted to determine if these effects were due to changes in activity of phospholipase C or in the second messenger responsive pathways that regulate production of PGF2 alpha. In both experiments, ovariectomized ewes were assigned to one of four treatment groups (control, estradiol, progesterone, progesterone and estradiol). Steroids were administered, in vivo, to mimic the changes that occur during the estrous cycle. On Day 16 of steroid treatment, endometrial tissue was collected and incubated, in vitro, to measure activity of phospholipase C and release of PGF2 alpha. Treatment with progesterone, in vivo, enhanced basal and oxytocin-induced activity of phospholipase C and release of PGF2 alpha, in vitro. Estradiol suppressed oxytocin-induced activity of phospholipase C, both in the presence and absence of progesterone. In contrast to its effects on phospholipase C, estradiol inhibited basal and oxytocin-induced release of PGF2 alpha when administered alone, but not when administered with progesterone. Steroids had similar effects on the release of PGF2 alpha induced by phorbol 12-myristate 13-acetate and A23187. It was concluded that progesterone and estradiol regulate endometrial release of PGF2 alpha by affecting both the activity of phospholipase C and its associated second messenger responsive pathways that may regulate production of PGF2 alpha.

  4. Improved quantification of 8-epi-prostaglandin F2 alpha and F2-isoprostanes by gas chromatography/triple-stage quadrupole mass spectrometry: partial cyclooxygenase-dependent formation of 8-epi-prostaglandin F2 alpha in humans.

    Science.gov (United States)

    Schweer, H; Watzer, B; Seyberth, H W; Nüsing, R M

    1997-12-01

    F2-isoprostanes are considered to be novel markers of lipid peroxidation. To study the in vivo formation of F2-isoprostanes, an improved method was developed for isotope dilution assays involving gas chromatography/triple-stage quadrupole mass spectrometry (GC/MS/MS) including thin-layer chromatography (TLC) (sum of all F2-isoprostanes) and high-performance liquid chromatographic (HPLC) purification (prostaglandin F2 alpha (PGF2 alpha) and 8-epi-PGF2 alpha). Following the addition of isotopically labeled prostaglandins to urine, the sample was acidified and applied to a C18 cartridge. After elution, prostaglandins were derivatized to pentafluorobenzyl esters and subjected to TLC. A broad zone was scratched off, isoprostanes were eluted and after formation of their trimethylsilyl ether derivatives the sum of F2-isoprostanes was determined by GC/MS/MS. For the determination of PGE2 alpha and 8-epi-PGF2 alpha prior to trimethylsilylation an additional HPLC step was performed and the fractions containing PGF2 alpha and 8-epi-PGF2 alpha were analyzed by GC/MS/MS. Using this technique, 8-epi-PGF2 alpha concentrations in urine samples as low as 5 pg ml-1 could be determined with high accuracy. The excretion rates of isoprostanes were studied in comparison with the classical prostaglandins in three different groups: healthy adults, healthy children and children with hyper-PGE syndrome (HPS), a pathological situation associated with a stimulated PGE2 synthesis. F2-isoprostanes represented the main arachidonic acid metabolites in these groups and 8-epi-PGF2 alpha excretion was comparable in its amount to the classical prostanoids. To delineate the cyclooxygenase-catalyzed contribution, the influence of indomethacin, an inhibitor of cyclooxygenases, on F2-isoprostane formation in healthy adults and in HPS children was analyzed. Significantly decreased excretion rates were observed 2 days after indomethacin administration for all prostanoids, including F2-isoprostanes and 8

  5. Effect of prostaglandins E1, E2, and F2 alpha on osteoclast formation in mouse bone marrow cultures

    Energy Technology Data Exchange (ETDEWEB)

    Collins, D.A.; Chambers, T.J. (St. George' s Hospital Medical School, London (United Kingdom))

    1991-02-01

    Prostaglandins (PG) act as direct inhibitors of mature osteoclasts, but although resorption-inhibition is also observed initially PG increase bone resorption in organ culture. This suggests that PG influence bone resorption in organ culture through actions on cell types other than mature osteoclasts. We have therefore tested the effects of PG E1, E2, and F2 alpha on the differentiation of osteoclastic phenotype in mouse bone marrow cultures using bone resorption and calcitonin receptors (CTR) as markers of osteoclastic differentiation. We found that PGE2 (10{sup {minus} 6}-10{sup {minus} 9} M) and PGE1 (10{sup {minus} 6} - 10{sup {minus} 7} M) induced a significant increase in CTR-positive cell numbers, to levels five to eight times those seen in controls and similar to the number induced by 1,25-dihydroxyvitamin D3 (1,25-(OH)2D3). Bone resorption was increased (10{sup {minus} 7} M PGE2 and 10{sup {minus} 6} M PGE1) in association with the increased CTR-positive cell numbers, suggesting that the PG also induced resorptive function. 1,25-(OH)2D3 increased both the number of CTR-positive cells and the extent of resorption per cell; the additional presence of PG did not affect the number of CTR-positive cells but did reduce bone resorption compared with 1,25-(OH)2D3 alone. PGF2 alpha had no significant effect on CTR-positive cell induction or bone resorption. The results suggest that PGE1 and E2 induce osteoclastic differentiation in mouse bone marrow cultures and inhibit the function of the osteoclasts thus formed.

  6. Inhibition of Mayaro virus replication by prostaglandin A1 and B2 in Vero cells.

    Science.gov (United States)

    Ishimaru, D; Marcicano, F G; Rebello, M A

    1998-09-01

    The effect of prostaglandins (PGA1 and PGB2) on the replication of Mayaro virus was studied in Vero cells. PGA1 and PGB2 antiviral activity was found to be dose-dependent. However, while 10 micrograms/ml PGB2 inhibited virus yield by 60%, at the same dose PGA1 suppressed virus replication by more than 90%. SDS-PAGE analysis of [35S]-methionine-labelled proteins showed that PGA1 did not alter cellular protein synthesis. In infected cells, PGA1 slightly inhibited the synthesis of protein C, while drastically inhibiting the synthesis of glycoproteins E1 and E2.

  7. Inhibition of Mayaro virus replication by prostaglandin A1 and B2 in Vero cells

    Directory of Open Access Journals (Sweden)

    Ishimaru D.

    1998-01-01

    Full Text Available The effect of prostaglandins (PGA1 and PGB2 on the replication of Mayaro virus was studied in Vero cells. PGA1 and PGB2 antiviral activity was found to be dose-dependent. However, while 10 µg/ml PGB2 inhibited virus yield by 60%, at the same dose PGA1 suppressed virus replication by more than 90%. SDS-PAGE analysis of [35S]-methionine-labelled proteins showed that PGA1 did not alter cellular protein synthesis. In infected cells, PGA1 slightly inhibited the synthesis of protein C, while drastically inhibiting the synthesis of glycoproteins E1 and E2.

  8. Inhibition of Mayaro virus replication by prostaglandin A(1) in Vero cells.

    Science.gov (United States)

    Burlandy, F M; Rebello, M A

    2001-01-01

    Prostaglandins exhibit antiviral activity against a wide variety of RNA and DNA viruses. In the present report, we describe the effect of cyclopentenone prostaglandin A(1) (PGA(1)) on Mayaro virus replication in Vero cells. Virus yield was significantly reduced at nontoxic concentrations which did not suppress DNA, RNA or protein synthesis in uninfected or infected cells. Antiviral action decreased if PGA(1) was added at later times after infection. In Mayaro virus-infected cells, PGA(1) inhibited the synthesis of virus proteins. This effect is accompanied by the induction of heat shock proteins (HSPs). Actinomycin D treatment not only inhibited the induction of HSPs but also partially prevented PGA(1) antiviral activity.

  9. Inhibition by indomethacin and aspirin of 15 hydroxy prostaglandin dehydrogenase in vitro

    DEFF Research Database (Denmark)

    Hansen, Harald S.

    1974-01-01

    15 Hydroxyprostaglandin dehydrogenase from bovine lung was purified 7.4 times to a specific activity of 1.4 mU/mg of protein. The isoelectric point was estimated at 5.4 and the molecular weight by gel filtration at 40,000. K(m) for prostaglandin E and for NAD was found to be 3.4 µM and 1.1 x 10M ...... respectively. The enzyme was inhibited by indomethacin and aspirin. The indomethacin inhibition was found to be non competitive to prostaglandin E having a K(i) = 1.4 x 10M and a K'(i) = 1.6 x 10M....

  10. Loss of prostaglandin F2alpha, but not thromboxane, responsiveness in pregnant human myometrium during labour.

    Science.gov (United States)

    Fischer, Deborah P; Hutchinson, Jonathon A; Farrar, Diane; O'Donovan, Peter J; Woodward, David F; Marshall, Kay M

    2008-04-01

    Prostaglandins (PG) E2, PGF2alpha and thromboxane (TX) mediate uterine contractility by targeting prostonoid EP, FP and TP receptors respectively. The aim of this study was to elucidate the function of these receptors in isolated human myometrium taken at term gestation prior to and following labour onset. Lower segment myometrial strips were immersed in organ baths in oxygenated Krebs' solution at 37 degrees C and connected to isometric force transducers. After equilibration, spontaneous activity and concentration responses to PGE2, PGF2alpha and U46619 (a stable TX mimetic) were measured as area under the curve and expressed as a percentage of the final contraction induced by hypotonic shock. Results were expressed as arithmetic means+/-s.e.m. and analysed using two-way ANOVA with Bonferroni's post hoc test. Myometrium excised at late gestation displayed the greatest spontaneous activity compared with the tissues taken during labour (Plabour onset. U46619 consistently stimulated concentration-dependent contractions (Plabour-associated disorders.

  11. Misoprostol inhibits gastric mucosal release of endogenous prostaglandin E2 and thromboxane B2 in healthy volunteers

    DEFF Research Database (Denmark)

    Mertz-Nielsen, A; Eskerod, O; Bukhave, K;

    1995-01-01

    antagonists in preventing ulcer relapse. It could be that prostaglandin analogues inhibit gastric mucosal synthesis or release of endogenous eicosanoids, thereby abrogating their own effects. This study, therefore, examined how a single therapeutic dose (200 micrograms) of misoprostol, a synthetic analogue....... These data show that misoprostol inhibits gastric mucosal synthesis of prostanoids. Decreased concentrations, or even a changed profile, of native eicosanoids modulating the release of inflammatory mediators from immune cells might explain why prostaglandin analogues have a comparatively poor clinical...

  12. Estrus synchronization in sheep and goats using combinations of GnRH, progestagen and prostaglandin F2alpha.

    Science.gov (United States)

    Titi, H H; Kridli, R T; Alnimer, M A

    2010-08-01

    The objective of this experiment was to evaluate the effect of GnRH, progestagen and prostaglandin F(2alpha) on estrus synchronization in sheep and goats. Sixty Awassi ewes and 53 Damascus does were used in the study. The experiment started at the beginning of the breeding season (June/July). The same treatments were applied to sheep and goats as follows: no treatment (CON), 14-day progestagen sponges and 600 IU equine chorionic gonadotropin (S), gonadotropin releasing hormone followed 5 days later by prostaglandin F(2alpha) (GP) and gonadotropin releasing hormone, progestagen sponges for 5 days and prostaglandin F(2alpha) on the day of sponge removal (GSP). None of the ewes in the S group lambed from mating during the induced cycle. A greater lambing rate (p synchronizing estrus and improving fecundity in sheep and goats. Although the use of GnRH-PGF(2alpha) was effective, the addition of progestagen sponges at the time of GnRH administration appeared to improve reproductive parameters.

  13. Concentrations of prostaglandins E2, F2 alpha and 6-keto-prostaglandin F1 alpha in the utero-ovarian venous plasma of nonpregnant and early pregnant ewes.

    Science.gov (United States)

    Silvia, W J; Ottobre, J S; Inskeep, E K

    1984-05-01

    The effect of pregnancy on concentrations of prostaglandins E2, F2 alpha and 6-keto-prostaglandin F1 alpha (PGE2, PGF2 alpha and 6-keto-PGF1 alpha) in utero-ovarian venous plasma was examined in ewes on Days 10 through 14 after estrus, an interval which includes the critical period for maternal recognition of pregnancy. The utero-ovarian vein ipsilateral to a corpus luteum was catheterized on Day 9 or 10 in 6 pregnant and 8 nonpregnant ewes. Five blood samples were collected at 30-min intervals for 2 h beginning at 0500 and 1700 h daily. Sampling began at 0500 h on the day after catheterization. The mean and variance within each 2-h collection period were calculated for each ewe. The natural logarithm of the variance in each collection period (ln variance) was used as an estimate of the fluctuations in secretory activity by the endometrial-conceptus complex. Patterns of the mean concentrations of PGE2 were different between pregnant and nonpregnant ewes (P less than 0.01); PGE2 being higher in the pregnant ewes beginning on Day 13. There was a trend for the patterns of ln variance in PGE2 to differ (P less than 0.1) with pregnancy status over the entire period; ln variance was greater in pregnant ewes beginning on Day 13. The patterns of the mean concentrations and ln variances for PGF2 alpha and 6-keto-PGF1 alpha did not differ between pregnant and nonpregnant ewes. There were significant increases in both of these prostaglandins over time, independent of pregnancy status (P less than 0.01). The association of higher concentrations of PGE2 in utero-ovarian venous plasma with early pregnancy is consistent with the hypothesis that PGE2, originating from the uterus and/or conceptus, is one factor involved in maintenance of the corpus luteum of pregnancy.

  14. [Maturation of the cervix uteri using prostaglandin F2 alpha before induction of labor in pathologic pregnancies].

    Science.gov (United States)

    Maria, B; Fayette, E; Stampf, F; Gandon, C; Gantrel, J; Barrat, J

    1983-01-01

    It is possible to induce labour in pathological pregnancies after artificial ripening of the cervix. The present study concerns 70 patients (45 primipara, 25 multipara). The main pathologies are hypertension of pregnancy and pregnancies past dates. Prostaglandin F2 alpha has been used with a Tylose gel containing 5 mg of PGF2 alpha introduced by the extra-amniotic route. The cervical change was noted using Bishop's score. The mean increase of the cervical score was 0.8 with the first PGF2 alpha gel. The total mean increase was 1.2. Two cases of hyperstimulation of the uterus were observed and they led to Caesarean section. Prostaglandin gel induced labour in 56% of the patients. The mean time between the introduction of the gel and the delivery was 14 h for primipara and 10 h for multipara. Other patients were induced with oxytocin on the following day. Epidural analgesia was widely used in this study (in 64% of cases). The mean duration of labour was 6 h 10 for primipara and 4 h 30 for multipara. 30% of the patients needed Caesarean section but there was a marked difference between primipara (36%) and multipara (4%). After a review of the literature the authors conclude that it is useful to ripen the cervix prostaglandin but, as foreign authors do, they think that PGE2 should be more efficient.

  15. Plasma oxytocin but not prostaglandin F2 alpha metabolite levels at cerclage may predict preterm delivery.

    Science.gov (United States)

    Behrens, O; Böhmer, S; Goeschen, K; Fuchs, A R

    1991-06-01

    Plasma oxytocin and prostaglandin F2 alpha metabolite (PGFM) concentrations were measured in 45 patients admitted for cerclage during the second trimester. Samples were collected before, 3 hours after, and 3 days after the Shirodkar procedure. Uterine activity was recorded by external tocography twice daily for 30 minutes. Twenty-eight women with uncomplicated pregnancy and commensurate gestational age served as controls. Cervical length, measured by ultrasonography, was significantly shorter before cerclage (36 +/- 2 mm) than after cerclage (43 +/- 2 mm) or compared with controls (48 +/- 1 mm). Bishop scores ranged from 3-6 (median 4) in the cerclage group and 0-1 (median 0) in controls. Fifteen cerclage patients and one control delivered preterm 5-22 weeks after the procedure. Initial plasma PGFM levels were significantly higher in cerclage patients than in controls. The cerclage procedure caused an immediate rise in plasma PGFM and a subsequent fall below initial levels to control values. Neither the initial levels of PGFM nor the increments 3 hours after cerclage correlated with the outcome of pregnancy. By contrast, plasma oxytocin levels before cerclage were significantly higher in patients who subsequently delivered preterm than in those who delivered at term. Cerclage resulted in a significant fall in plasma oxytocin at 3 hours in patients with preterm delivery, but after 3 days the oxytocin levels had returned to the precerclage values. Patients who had increased uterine contractions had significantly higher plasma oxytocin levels but lower PGFM levels than those without contractions.(ABSTRACT TRUNCATED AT 250 WORDS)

  16. Inhibition of prostaglandin-H-synthase by o-phenylphenol and its metabolites.

    Science.gov (United States)

    Freyberger, A; Degen, G H

    1998-10-01

    Chronic administration of o-phenylphenol (OPP) is known to induce urinary bladder tumours in the Fischer rat. The underlying toxic mechanism is poorly understood. Recently, arachidonic acid (ARA)-dependent, prostaglandin-H-synthase (PHS)-catalysed metabolic activation of the OPP metabolite phenylhydroquinone (PHQ) to a genotoxic species was suggested to be involved in OPP toxicity. To investigate this hypothesis in more detail, we have studied the effects of OPP and its metabolites on PHS. When microsomal PHS from ovine seminal vesicles (OSV) was used as enzyme source, both OPP, PHQ, and 2-phenyl-1,4-benzoquinone (PBQ) inhibited PHS-cyclooxygenase. The inhibitory potency was inversely related to the ARA concentration in the assay; at 7 microM ARA IC50-values were: 13 microM (OPP), 17 microM (PHQ), and 190 microM (PBQ). In cells cultured from OSV, which express high PHS activity, 40 microM OPP almost completely suppressed prostaglandin formation. Studies with microsomal PHS demonstrated that PHQ was an excellent substrate for PHS-peroxidase; both ARA and hydrogen peroxide supported oxidation to PBQ. OPP was only a poor substrate for PHS, but inhibited the ARA-mediated and to a lesser extent also the hydrogen peroxide-mediated in vitro oxidation of PHQ. Moreover, PHQ at up to moderately cytotoxic concentrations (50 microM) did not induce micronuclei in OSV cell cultures. Taken together, our findings do not provide evidence for an ARA-dependent, PHS-catalysed formation of genotoxic species from PHQ. Moreover, it seems to be questionable whether such activation can effectively occur in vivo, since OPP and PHQ turned out to be efficient cyclooxygenase inhibitors, and high levels of OPP and PHQ were found at least in the urine of OPP-treated rats. On the other hand, inhibition of the formation of cytoprotective prostaglandins in the urogenital tract may play a crucial role in OPP-induced bladder carcinogenesis.

  17. Prostaglandin A1 inhibits replication of Mayaro virus in Aedes albopictus cells.

    Science.gov (United States)

    Barbosa, J A; Rebello, M A

    1995-01-01

    Prostaglandin A1 (PGA1) reduced Mayaro virus replication in Aedes albopictus (mosquito) cells in culture. The highest nontoxic dose of PGA1, 7.5 microM, decreased virus production by 90%. In Mayaro virus-infected cells, PGA1 inhibited virus-specific protein synthesis. However, in mock-infected cells the presence of PGA1 stimulated the synthesis of several proteins with molecular masses of 70, 57 and 23 kDa, respectively. The data obtained from this study show that PGA1 plays a role in the metabolic regulation of Aedes albopictus cells, blocking the synthesis of Mayaro virus and inducing the synthesis of cellular polypeptides.

  18. Aspirin inhibits interleukin 1-induced prostaglandin H synthase expression in cultured endothelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Wu, K.K.; Sanduja, R.; Tsai, A.L.; Ferhanoglu, B.; Loose-Mitchell, D.S. (Univ. of Texas Medical School, Houston (United States))

    1991-03-15

    Prostaglandin H (PGH) synthase is a key enzyme in the biosynthesis of prostaglandins, thromboxane, and prostacyclin. In cultured human umbilical vein endothelial cells, interleukin 1 (IL-1) is known to induce the synthesis of this enzyme, thereby raising the level of PGH synthase protein severalfold over the basal level. Pretreatment with aspirin at low concentrations inhibited more than 60% of the enzyme mass and also the cyclooxygenase activity in IL-1-induced cells with only minimal effects on the basal level of the synthase enzyme in cells without IL-1. Sodium salicylate exhibited a similar inhibitory action whereas indomethacin had no apparent effect. Similarly low levels of aspirin inhibited the increased L-({sup 35}S)methionine incorporation into PGH synthase that was induced by IL0-1 and also suppressed expression of the 2.7-kilobase PGH synthase mRNA. These results suggest that in cultured endothelial cells a potent inhibition of eicosanoid biosynthetic capacity can be effected by aspirin or salicylate at the level of PGH synthase gene expression. The aspirin effect may well be due to degradation of salicylate.

  19. The 5-lipoxygenase inhibitor, zileuton, suppresses prostaglandin biosynthesis by inhibition of arachidonic acid release in macrophages

    Science.gov (United States)

    Rossi, A; Pergola, C; Koeberle, A; Hoffmann, M; Dehm, F; Bramanti, P; Cuzzocrea, S; Werz, O; Sautebin, L

    2010-01-01

    BACKGROUND AND PURPOSE Zileuton is the only 5-lipoxygenase (5-LOX) inhibitor marketed as a treatment for asthma, and is often utilized as a selective tool to evaluate the role of 5-LOX and leukotrienes. The aim of this study was to investigate the effect of zileuton on prostaglandin (PG) production in vitro and in vivo. EXPERIMENTAL APPROACH Peritoneal macrophages activated with lipopolysaccharide (LPS)/interferon γ (LPS/IFNγ), J774 macrophages and human whole blood stimulated with LPS were used as in vitro models and rat carrageenan-induced pleurisy as an in vivo model. KEY RESULTS Zileuton suppressed PG biosynthesis by interference with arachidonic acid (AA) release in macrophages. We found that zileuton significantly reduced PGE2 and 6-keto prostaglandin F1α (PGF1α) levels in activated mouse peritoneal macrophages and in J774 macrophages. This effect was not related to 5-LOX inhibition, because it was also observed in macrophages from 5-LOX knockout mice. Notably, zileuton inhibited PGE2 production in LPS-stimulated human whole blood and suppressed PGE2 and 6-keto PGF1α pleural levels in rat carrageenan-induced pleurisy. Interestingly, zileuton failed to inhibit the activity of microsomal PGE2 synthase1 and of cyclooxygenase (COX)-2 and did not affect COX-2 expression. However, zileuton significantly decreased AA release in macrophages accompanied by inhibition of phospholipase A2 translocation to cellular membranes. CONCLUSIONS AND IMPLICATION Zileuton inhibited PG production by interfering at the level of AA release. Its mechanism of action, as well as its use as a pharmacological tool, in experimental models of inflammation should be reassessed. PMID:20880396

  20. Opposing effects of nitric oxide and prostaglandin inhibition on muscle mitochondrial VO2 during exercise

    DEFF Research Database (Denmark)

    Boushel, Robert C; Fuentes, Teresa; Hellsten, Ylva

    2012-01-01

    Nitric oxide (NO) and prostaglandins (PG) together play a role in regulation blood flow during exercise. NO also regulates mitochondrial oxygen consumption through competitive binding to cytochrome c oxidase. Indomethacin both uncouples and inhibits the electron transport chain in a concentration......-dependent manner, and thus inhibition of NO and PG may regulate both muscle oxygen delivery and utilization. The purpose of this study was to examine the independent and combined effects of NO and PG blockade (L-NMMA and indomethacin respectively) on mitochondrial respiration in human muscle following knee......-stimulated state 3 respiration with substrates for complex I (glutamate, malate) was reduced 50% by Indo. State 3 O(2) flux with complex I and II substrates was reduced less with both Indo (20%) and L-NMMA + Indo (15%) compared to CON. The results indicate that indomethacin reduces state 3 mitochondrial...

  1. Reproducibility of dorsal hand vein responses to phenylephrine and prostaglandin F2 alpha using the dorsal hand vein compliance method.

    Science.gov (United States)

    Schindler, C; Grossmann, M; Dobrev, D; Francke, K; Ravens, U; Kirch, W

    2003-03-01

    Assessment of drug-induced venodilation by the dorsal hand vein compliance method requires stable constriction of the vein. This study was designed to investigate intra- and intersubject reproducibility of the venous preconstriction technique in response to phenylephrine and prostaglandin F2 alpha and to determine the influence of basal vein size. Twelve healthy male nonsmokers participated in a prospective cross-over study. Inter- and intrasubject variability was tested in response to phenylephrine and PGF2 alpha on different study days in the same hand vein. The dose of the respective constrictor causing approximately 80% constriction of the vein (ED80) was determined and infused for another 100 minutes. Actual vein size was measured every 5 minutes. Coefficient of variation and regression analyses were performed to analyze influence of vessel size on ED80 of the respective constrictor. Adjusted constriction levels were stable and well reproducible in all subjects. The intersubject coefficient of variation of ED80 ranged from 0.9% to 6.7% for phenylephrine and from 0.9% to 6.9% for PGF2 alpha. Whereas responses to phenylephrine were independent of basal vein diameter, there was a positive correlation between ED80 of PGF2 alpha and basal vein size. Thus, the hand vein compliance method is a suitable method to study dilatory responses in phenylephrine- or PGF2 alpha-constricted veins with considerable interindividual but small intraindividual variability. However, in such studies, phenylephrine appears to be a more reliable tool than PGF2 alpha.

  2. Resveratrol inhibits prostaglandin formation in IL-1β-stimulated SK-N-SH neuronal cells

    Directory of Open Access Journals (Sweden)

    Candelario-Jalil Eduardo

    2009-09-01

    Full Text Available Abstract Resveratrol, a polyphenol present in grapes and red wine, has been studied due to its vast pharmacological activity. It has been demonstrated that resveratrol inhibits production of inflammatory mediators in different in vitro and in vivo models. Our group recently demonstrated that resveratrol reduced the production of prostaglandin (PG E2 and 8-isoprostane in rat activated microglia. In a microglial-neuronal coculture, resveratrol reduced neuronal death induced by activated microglia. However, less is known about its direct roles in neurons. In the present study, we investigated the effects of resveratrol on interleukin (IL-1β stimulated SK-N-SH cells. Resveratrol (0.1-5 μM did not reduce the expression of cyclooxygenase (COX-2 and microsomal PGE2 synthase-1 (mPGES-1, although it drastically reduced PGE2 and PGD2 content in IL-1β-stimulated SK-N-SH cells. This effect was due, in part, to a reduction in COX enzymatic activity, mainly COX-2, at lower doses of resveratrol. The production of 8-iso-PGF2α, a marker of cellular free radical generation, was significantly reduced by resveratrol. The present work provides evidence that resveratrol reduces the formation of prostaglandins in neuroblastoma cells by reducing the enzymatic activity of inducible enzymes, such as COX-2, and not the transcription of the PG synthases, as demonstrated elsewhere.

  3. Prostaglandin E2 role in inhibition of joint cartilage collagen destruction in patients with osteoarthritis

    Directory of Open Access Journals (Sweden)

    E V Chetina

    2009-01-01

    Full Text Available Prostaglandin E2 role in inhibition of articular cartilage collagen degradation in patients with osteoarthritis. Objective. To assess prostaglandin E2 (PGE2 role in inhibition of type II collagen digestion in explants of articular cartilage of pts with osteoarthritis (OA. Material and methods. Explants of articular cartilage of pts with OA were cultured with PGE2 1pg to 10 ng/ml. Type II collagen digestion was assessed with immuno-enzyme assay. Gene expression was evaluated with PCR in real time. Results. PGE2 10 pg/ml as well as transforming growth factor β2 (TGFβ2 suppressed type II collagen digestion in explants of articular cartilage of pts with OA. This concentration of PGE2 did not suppress proteoglycan (aggrecan degradation. Gene expression analysis in 5 OA pts showed that PGE2 10 pg/ml suppressed metallomonooxigenase (MMP-13, MMP-1 and marker of chondrocyte hypertrophy type X collagen (COL10A1 as well as proinflammatory cytokines interleukine (IL-1β and tumor necrosis factor (TNFα. Naproxen, nonselective cyclooxygenase(COX-2 and 1 inhibitor concentration from 5 to 30 mcg/ml blocked TGFβ2 induced collagen digestion inhibition proving that PGE2 mediate influence of this growth factor. Naproxen concentration 5 mcg/ml increased collagen degradation. Conclusion. The study showed that PGE2 is a chondroprotector because it is able to suppress selectively OA pts cartilage collagen degradation. Beside that cartilage chondrocyte hypertrophy in OA connected functionally with increased collagen digestion is also regulated by low concentrations of PGE2

  4. Oxytocin- and aluminium fluoride-induced phospholipase C activity and prostaglandin F2 alpha secretion during the ovine luteolytic period.

    Science.gov (United States)

    Graf, G A; Burns, P D; Silvia, W J

    1998-03-01

    A series of studies was conducted to characterize changes in components of the cell signalling cascade that mediates oxytocin-induced prostaglandin F2 alpha (PGF2 alpha) synthesis at the onset of luteolysis in sheep. In the first experiment, caruncular tissue was dissected from 20 ewes on days 12-15 of the oestrous cycle, and incubated for the measurement of phospholipase C (PLC) activity or secretion of PGF2 alpha. Activation of GTP-binding proteins with aluminium fluoride stimulated both inositol phosphate accumulation and PGF2 alpha secretion on all days examined. However, oxytocin did not stimulate PLC activity or PGF2 alpha accumulation until day 13. While the ability of oxytocin to stimulate PLC activity increased after day 13, oxytocin-induced PGF2 alpha secretion declined slightly from day 13 to 15, suggesting that cell signalling components downstream from PLC modulate the response to oxytocin after day 13. Oxytocin failed to stimulate PGF2 alpha synthesis on day 14 after oestrus. Secretion of endogenous luteal oxytocin may have rendered uterine tissues collected on day 14 refractory to oxytocin in vitro. Therefore, a second study was conducted in ovariectomized, steroid replaced ewes. Ovarian steroids were administered to mimic endogenous changes in progesterone and oestradiol. The temporal patterns of PGF2 alpha synthesis in response to oxytocin and pharmacological agents were similar to uterine tissues from cyclic ewes in the first experiment; however, the magnitude of the response was less. These data suggest that oxytocin receptors are absent or are not coupled to PLC until day 13 after oestrus.

  5. Relationship between urinary prostaglandin E2 and F2 alpha excretion and plasma arginine vasopressin during renal concentrating and diluting tests in renal transplant recipients.

    Science.gov (United States)

    Pedersen, E B; Christensen, P; Danielsen, H; Eiskjaer, H; Jespersen, B; Knudsen, F; Kornerup, H J; Leyssac, P P; Nielsen, A H; Sørensen, S S

    1987-10-01

    Urinary excretion of prostaglandin E2 (PGE2 and F2 alpha (PGF2 alpha) and plasma concentration of arginine vasopressin (AVP) were determined during urinary concentrating and diluting tests in renal transplant recipients and control subjects. During the concentrating test PGE2 and PGF2 alpha remained unchanged in the renal transplant recipients, whereas both PGE2 and PGF2 alpha were significantly reduced in the control subjects. During the diluting test PGE2 and PGF2 alpha increased in both groups but, contrary to PGF2 alpha, PGE2 was significantly higher in all periods in the transplant recipients compared to the controls. However, the prostaglandin excretion rates per kidney were significantly higher in the renal transplant recipients than control subjects, for all periods during both the concentrating and the diluting test. Arginine vasopressin was significantly higher in renal transplant recipients than control subjects during basal conditions, increased to a significantly higher level in the transplant recipients after thirst, but was reduced to the same levels in the two groups during the diluting test. It is concluded that the increased excretion of prostaglandins in renal transplant recipients may be a compensatory phenomenon representing an adaptation to a reduced renal mass in order to maintain adequate renal water excretion. Although a direct relationship between the prostaglandin excretions of PGE2 and PGF2 alpha and AVP does not seem to exist, it is possible that the higher prostaglandin excretion in the renal transplant recipients may be a counterbalancing mechanism to the higher AVP level, which most likely is secondary to a decreased responsiveness to vasopressin of the renal collecting ducts in the transplanted kidney.

  6. Prostaglandin A1 inhibits increases in intracellular calcium concentration, TXA2 production and platelet activation

    Institute of Scientific and Technical Information of China (English)

    Yi ZHU; Zhen-lun GU; Zhong-qin LIANG; Hui-lin ZHANG; Zheng-hong QIN

    2006-01-01

    Aim: In our previous studies we found that cyclopentenane prostaglandin A1 (PGA1) had neuroprotective effects in a rodent ischemic model. In the present study we aimed to investigate the inhibitory effect of PGA1 on platelet function. Method: The rate of aggregation of human platelets was measured by using turbidimetry. The rate of adhesion of platelets to cultured endothelial cells was determined by using [3H]-adenine labeled platelets. 5-Hydroxytryptamine release from platelets was measured with O-phthaldialdehyde fluorospectrophotometry. The levels of TXB2, a stable metabolite of TXA2, were determined by radioimmunoassay. Alternations in platelet morphology were observed using an electron microscope, and the intraplatelet free calcium concentrations were measured with Fluo-3/AM FCM assay. Results: PGA1 significantly inhibited thrombin-collagen-and ADP-induced aggregation and adhesion of platelets. The morphological changes of platelets induced by thrombin were blocked by PGA1. PGA1 inhibited the release of 5-hydroxytyptamine from dense granules and the synthesis of TXA2. Conclusion: PGA1 inhibits the activation of platelets probably through blocking increases in intracellular calcium concentration and TXA2 synthesis.

  7. Prostaglandin E₂ inhibits human lung fibroblast chemotaxis through disparate actions on different E-prostanoid receptors.

    Science.gov (United States)

    Li, Ying-Ji; Wang, Xing-Qi; Sato, Tadashi; Kanaji, Nobuhiro; Nakanishi, Masanori; Kim, Miok; Michalski, Joel; Nelson, Amy J; Sun, Jian-Hong; Farid, Maha; Basma, Hesham; Patil, Amol; Toews, Myron L; Liu, Xiangde; Rennard, Stephen I

    2011-01-01

    The migration of fibroblasts is believed to play a key role in both normal wound repair and abnormal tissue remodeling. Prostaglandin E (PGE)(2), a mediator that can inhibit many fibroblast functions including chemotaxis, was reported to be mediated by the E-prostanoid (EP) receptor EP2. PGE(2), however, can act on four receptors. This study was designed to determine if EP receptors, in addition to EP2, can modulate fibroblast chemotaxis. Using human fetal lung fibroblasts, the expression of all four EP receptors was demonstrated by Western blotting. EP2-selective and EP4-selective agonists inhibited both chemotaxis toward fibronectin in the blindwell assay and migration in a wound-closure assay. In contrast, EP1-selective and EP3-selective agonists stimulated cell migration in both assay systems. These results were confirmed using EP-selective antagonists. The role of both EP2 and EP4 receptors in mediating the PGE(2) inhibition of chemotaxis was also confirmed by small interfering RNA suppression. Furthermore, the role of EP receptors was confirmed by blocking the expected signaling pathways. Taken together, these results demonstrate that PGE(2) can act on multiple EP receptors in human lung fibroblasts, to exert disparate effects. Alterations in EP receptor expression may have the potential to alter PGE(2) action. Targeting specific EP receptors may offer therapeutic opportunities in conditions characterized by abnormal tissue repair and remodeling.

  8. Prostaglandin E1 inhibits collagenase gene expression in rabbit synoviocytes and human fibroblasts.

    Science.gov (United States)

    Salvatori, R; Guidon, P T; Rapuano, B E; Bockman, R S

    1992-07-01

    Cartilage breakdown, as seen in inflammatory and degenerative joint diseases, can be mediated by proteolytic enzymes, such as the metalloproteinase collagenase, the only enzyme able to digest collagen at neutral pH. In vitro collagenase gene expression can be stimulated by the phorbol ester tumor promoter 12-O-tetradecanoyl-phorbol-13-acetate. We have investigated the effect of prostaglandin E1 (PGE1) on 12-O-tetradecanoyl-phorbol-13-acetate-stimulated collagenase mRNA levels in the rabbit synoviocyte cell line HIG-82. PGE1, but not PGE2 or PGF2 alpha, was able to selectively reduce collagenase mRNA levels in a dose-dependent fashion. PGE1 markedly increased intracellular levels of cAMP, while PGE2 and PGF2 alpha had little or no effect on cAMP production in the HIG-82 synoviocytes. Agents known to increase intracellular cAMP levels, such as the adenyl cyclase activator forskolin and the phosphodiesterase inhibitor 3-isobutyl-1-methylxanthine (IBMX), mimicked the effect of PGE1, on collagenase mRNA levels. PGE1, forskolin, and IBMX also decreased collagenase mRNA levels in human skin fibroblasts, demonstrating that this observation was not unique to the HIG-82 cell line. Transient transfection experiments carried out in HIG-82 cells using a 1.2-kilobase portion of the 5'-flanking region of the human collagenase gene linked to the reporter gene luciferase demonstrated that PGE1, forskolin, and IBMX exert their inhibitory effect on the promoter region of the collagenase gene.

  9. Effects of drugs inhibiting prostaglandin or leukotriene biosynthesis on postirradiation haematopoiesis in mouse

    Energy Technology Data Exchange (ETDEWEB)

    Kozubik, A.; Hofmanova, J.; Pospisil, M.; Netikova, J.; Hola, J.; Lojek, A. (Ceskoslovenska Akademie Ved, Brno (Czech Republic). Biofysikalni Ustav)

    1994-03-01

    Two non-steroidal anti-inflammatory drugs, i.e. indomethacin (INDO), an inhibitor of prostaglandin production, and esculetin (ESCUL), an inhibitor of leukotriene production, were tested for their ability to modify haematopoiesis in three experimental systems: (a) in vitro clonal proliferation of marrow GM-CFC from the irradiated mouse was found to be augmented by addition of INDO at a low concentration, and inhibited by ESCUL in a dose-dependent manner; (b) in the lethally irradiated and bone marrow-transplanted mice treated with the drugs in the postirradiation period, stimulatory effects of INDO on CFU-S and GM-CFC populations and an inhibitory effect of ESCUL on GM-CFC were observed; and (c) when the drugs were administered i.p. to mice 1 h before 5-Gy irradiation, INDO enhanced the postirradiation recovery of haematopoietic indices such the numbers of CFU-S, GM-CFC, peripheral blood granuloctyes, and nucleated bone marrow cells, while ESCUL had no effect or even inhibited the recovery of these indices. (author).

  10. Effects of progesterone withdrawal on uterine secretion of prostaglandin F2 alpha in response to oxytocin in ewes.

    Science.gov (United States)

    Kaminski, M A; Hayes, S H; Silvia, W J

    1997-01-01

    Two experiments were conducted to determine if withdrawal of progesterone during the luteal phase of the oestrous cycle affected the ability of the ovine uterus to secrete prostaglandin F2 alpha (PGF2 alpha) in response to oxytocin. In Experiment 1, 18 ewes were ovariectomized on Day 9 and Day 12 after oestrus. Ewes were subdivided into three treatment groups (n = 6 per group): Group-1 ewes underwent sham surgery; Group-2 ewes received oestradiol (OVX + O); and Group-3 ewes received oestradiol + progesterone (OVX + O,P). Oxytocin was administered to each ewe on Days 10, 13 and 15 after oestrus. Concentrations of 13, 14-dihydro-15-keto-PGF2 alpha (PGFM) were determined in samples of jugular venous blood for 2 h after oxytocin challenge. The magnitude of the PGFM response 24 h after ovariectomy was greater (P Day 11 and assigned to 1 of 4 treatment groups (n = 6 per group): Group 1, no steroid replacement (OVX); Group 2, oestradiol replacement (OVX + O); Group 3, progesterone replacement (OVX + P); or Group 4, progesterone + oestradiol replacement (OVX + O,P). Ewes received oxytocin on Day 12 and Day 15. On Day 12, uterine secretory responsiveness to oxytocin was greatest in ewes in the OVX + O group (P < 0.1). Responsiveness was low in ewes in the OVX group, as it was in ewes in both groups that received progesterone replacement. Therefore, the increase in uterine secretory responsiveness to oxytocin following progesterone withdrawal is dependent on oestradiol replacement.

  11. [Therapeutic interruption of pregnancy in the second trimester after preparation of the cervix with prostaglandins F2 alpha].

    Science.gov (United States)

    Maria, B; Stampf, F; Barrat, J

    1983-01-01

    The use of prostaglandins is one of the best techniques for second trimester abortion. The authors present 40 patients aborted by a new two stage technique: First: ripening of the cervix a tylose gel containing 5 or 10 mg PGF2 alpha every 12 hours during 3 days. Then, if abortion is not obtained, previously published techniques are used: intra-amniotic injection (40 mg PGF2 alpha) or intra-cervical infusion (2 mg/hour). The mean duration of these abortions is 52 hours using 29 mg of PGF2 alpha. 22 patients aborted during ripening (mean = 27 hours), 12 patients needed an intracervical infusion (mean = 88 hours) and 6, an intra-amniotic injection (mean = 72 hours). It seems that abortion is easier when pregnancy is earlier, under 20 weeks of gestation. Few side effects were observed: only three cases of fever with a single case of endometritis. Failure of this technique occurred in five patients (4 aborted outside the time allowed for, and one needed instrumental extraction). With this technique, the mean duration is longer than those previously described in the literature but the efficiency is over 90%.

  12. INHIBITION OF MAYARO VIRUS REPLICATION BY PROSTAGLANDIN A1 IN Aedes albopictus CELLS

    Directory of Open Access Journals (Sweden)

    Joel Antonio Barbosa

    1998-09-01

    Full Text Available Prostaglandin A1 (PGA1 inhibits Mayaro virus replication in Aedes albopictus cells at nontoxic doses to uninfected cells. At 10 µg/ml, PGA1 decreases virus production by 90%. The presence of PGA1 during virus adsorption, with no treatment after infection, reduces virus yield by 41%. Antiviral activity is observed even when treatment starts at one or two hours post-infection. However, in cells pre-treated with PGA1 during 24 hours, virus replication is not impaired. Thus, events ocurring during initial stages of infection and after virus adsorption and penetration must be the target of PGA1 action. SDS-PAGE analysis of 35S-methionine labelled proteins shows that PGA1 inhibits the synthesis of viral proteins and induces the synthesis of polypeptides with molecular weight of 70 kDa, 57 kDa and 23 kDa. In cells pre-treated with actinomycin D the induction of those proteins is suppressed. In addition, actinomycin D treatment prevents PGA1antiviral activity, indicating that PGA1-induced stress proteins are probably involved in this mechanism.Prostaglandin A1 (PGA1 inibe a replicação do vírus Mayaro em células de Aedes albopictus em doses não tóxicas para células não infectadas. A presença de PGA1 durante o período de adsorção, reduz a produção do vírus em 41%. A atividade antiviral é observada mesmo quando o tratamento é iniciado com 1 ou 2 horas após a infecção. Entretanto, em células pré-tratadas com PGA1 durante 24 h a replicação viral é inalterada. A análise das proteínas marcadas com 35S-metionina, por eletroforese em gel de poliacrilamida, mostra que a PGA1 inibe a síntese de proteínas virais e induz a síntese de polipeptídeos com peso molecular de 70 Kda, 57 Kda e 23 Kda. Em células pré-tratadas com actinomicina D observa-se um bloqueio da atividade antiviral, indicando que as proteínas de estresse induzidas pela PGA1 estão envolvidas neste mecanismo.

  13. Carnosol and carnosic acids from Salvia officinalis inhibit microsomal prostaglandin E2 synthase-1.

    Science.gov (United States)

    Bauer, Julia; Kuehnl, Susanne; Rollinger, Judith M; Scherer, Olga; Northoff, Hinnak; Stuppner, Hermann; Werz, Oliver; Koeberle, Andreas

    2012-07-01

    Prostaglandin E(2) (PGE(2)), the most relevant eicosanoid promoting inflammation and tumorigenesis, is formed by cyclooxygenases (COXs) and PGE(2) synthases from free arachidonic acid. Preparations of the leaves of Salvia officinalis are commonly used in folk medicine as an effective antiseptic and anti-inflammatory remedy and possess anticancer activity. Here, we demonstrate that a standard ethyl acetate extract of S. officinalis efficiently suppresses the formation of PGE(2) in a cell-free assay by direct interference with microsomal PGE(2) synthase (mPGES)-1. Bioactivity-guided fractionation of the extract yielded closely related fractions that potently suppressed mPGES-1 with IC(50) values between 1.9 and 3.5 μg/ml. Component analysis of these fractions revealed the diterpenes carnosol and carnosic acid as potential bioactive principles inhibiting mPGES-1 activity with IC(50) values of 5.0 μM. Using a human whole-blood assay as a robust cell-based model, carnosic acid, but not carnosol, blocked PGE(2) generation upon stimulation with lipopolysaccharide (IC(50) = 9.3 μM). Carnosic acid neither inhibited the concomitant biosynthesis of other prostanoids [6-keto PGF(1α), 12(S)-hydroxy-5-cis-8,10-trans-heptadecatrienoic acid, and thromboxane B(2)] in human whole blood nor affected the activities of COX-1/2 in a cell-free assay. Together, S. officinalis extracts and its ingredients carnosol and carnosic acid inhibit PGE(2) formation by selectively targeting mPGES-1. We conclude that the inhibitory effect of carnosic acid on PGE(2) formation, observed in the physiologically relevant whole-blood model, may critically contribute to the anti-inflammatory and anticarcinogenic properties of S. officinalis.

  14. Biochemical and clinical evaluation of the efficiency of intracervical extraamniotic prostaglandin F2 alpha and intravenous oxytocin infusion to induce labour at term.

    Science.gov (United States)

    Kaminski, K; Rechberger, T; Oleszczuk, J; Jakowicki, J; Oleszczuk, J

    1994-08-01

    A prospective randomized study of 296 patients was undertaken to evaluate the efficiency of 15 mg prostaglandin F2 alpha (PGF2 alpha) suspended in tylose gel and applied intracervically for labour induction. The control group was treated with standard oxytocin intravenous infusion. Results indicated that local PGF2 alpha was superior to oxytocin therapy in shortening the duration of labour (6.3 +/- 2.3 versus 8.1 +/- 2.6 hours, p < 0.05). Only 19% of the patients treated with PGF2 alpha required oxytocin augmentation during labour. Our data suggest that PGF2 alpha treatment is associated with few maternal side-effects, few failed inductions, a low operative delivery rate and favourable neonatal outcome. To investigate the influence of PGF2 alpha for labour promotion we have measured interstitial collagenase and elastase activity in the lower uterine segment after both methods of labour induction. The total collagenase activity was 22 times higher in tissue samples obtained from patients in active spontaneous and oxytocin-induced labour, compared with women not in labour (at term) (p < 0.001). The total interstitial elastase activity was 2-fold higher in women in active labour than in patients at term (p < 0.03). A significantly higher collagenase and elastase activity was observed in uterine specimens obtained from patients treated with PGF2 alpha compared to oxytocin, and this indicates that cervical collagen may be digested more quickly in the presence of exogenous prostaglandin F2 alpha.

  15. The relationship between the production and the anti-gonadotrophic action of prostaglandin F 2 alpha in luteal cells from the marmoset monkey (Callithrix jacchus) in the early and mid-luteal phase.

    Science.gov (United States)

    Webley, G E; Michael, A E; Abayasekara, D R E

    2010-04-01

    To address the potential luteolytic role for prostaglandin F(2 alpha) (PGF(2 alpha)) in the corpus luteum of the common marmoset monkey (Callithrix jacchus), the ability of marmoset luteal cells, maintained in monolayer culture, to produce PGF(2 alpha) was determined in vitro in the presence and absence of human chorionic gonadotrophin (hCG) and other established pharmacological modulators of PGF(2 alpha) synthesis. We also assessed the effects of the PGF(2 alpha) analogue, cloprostenol, on progesterone output from luteal cells isolated in the early luteal phase versus the mid-luteal phase (days 3 and 14 post ovulation, respectively). Cloprostenol had no effect on progesterone output from luteal cells isolated on day 3 of the luteal phase, whereas it significantly inhibited both basal and hCG-stimulated progesterone synthesis by day 14 luteal cells during the culture period 48-72 h (Pmarmoset monkey appears to involve changes in both the luteal cell response to and production of PGF(2 alpha).

  16. Prostaglandin E2 inhibits platelet-derived growth factor-stimulated cell proliferation through a prostaglandin E receptor EP2 subtype in rat hepatic stellate cells.

    Science.gov (United States)

    Koide, Shigeki; Kobayashi, Yoshimasa; Oki, Yutaka; Nakamura, Hirotoshi

    2004-09-01

    Prostaglandin (PG) E2 inhibits hepatic stellate cell (HSC) mitogenesis. PGE-specific receptors are divided into four subtypes that are coupled either to Ca2+ mobilization (EP1 and EP3) or to the stimulation of adenyl cyclase (EP2 and EP4). The aims of the current study were to identify PGE receptor subtypes in cultured rat HSC and to examine which PGE receptor subtype(s) mediates the inhibitory effect of PGE2 on platelet-derived growth factor (PDGF)-stimulated proliferation. Reverse transcription-polymerase chain reaction analysis was performed to detect PGE receptor subtype mRNA expression. Cell proliferation was determined by measuring [3H]thymidine incorporation, and intracellular cyclic AMP was measured by radioimmunoassay. Cultured rat HSC expressed mRNAs for all four subtypes of PGE receptor. PGE2- and EP2-selective agonist produced dose-dependent inhibitory effects on PDGF-stimulated proliferation. Neither EP1-, EP3-, nor EP4-selective agonists showed any inhibitory effect. An adenylate cyclase inhibitor strongly blunted the inhibition of DNA synthesis elicited by PGE2 and the EP2 agonist. The EP2 agonist generated higher and more prolonged increases in intracellular cyclic AMP than the EP4 agonist. Activation of the PGE EP2 receptor has an antiproliferative effect in HSC that may be mediated by cyclic AMP-related signal transduction pathways.

  17. Extra-amniotic prostaglandin F2alpha in gel for prelabor cervical ripening.

    Science.gov (United States)

    Thiery, M; Parewyck, W; de Gezelle, H; van Kets, H; Derom, R; Martens, G

    1978-08-01

    In 22 normal term gravidas with unfavorable cervix, 5 mg PGF2alpha in Tylose gel was instilled into the extra-amniotic space. The treatment improved the cervical state so much that the women could be successfully induced by conventional methods. The procedure was well tolerated by the mother and it appeared to be perinatally safe.

  18. Prostaglandin metabolite induces inhibition of TRPA1 and channel-dependent nociception

    Directory of Open Access Journals (Sweden)

    Weng Yingqi

    2012-09-01

    Full Text Available Abstract Background The Transient Receptor Potential (TRP ion channel TRPA1 is a key player in pain pathways. Irritant chemicals activate ion channel TRPA1 via covalent modification of N-terminal cysteines. We and others have shown that 15-Deoxy-Δ12, 14-prostaglandin J2 (15d-PGJ2 similarly activates TRPA1 and causes channel-dependent nociception. Paradoxically, 15d-PGJ2 can also be anti-nociceptive in several pain models. Here we hypothesized that activation and subsequent desensitization of TRPA1 in dorsal root ganglion (DRG neurons underlies the anti-nociceptive property of 15d-PGJ2. To investigate this, we utilized a battery of behavioral assays and intracellular Ca2+ imaging in DRG neurons to test if pre-treatment with 15d-PGJ2 inhibited TRPA1 to subsequent stimulation. Results Intraplantar pre-injection of 15d-PGJ2, in contrast to mustard oil (AITC, attenuated acute nocifensive responses to subsequent injections of 15d-PGJ2 and AITC, but not capsaicin (CAP. Intraplantar 15d-PGJ2—administered after the induction of inflammation—reduced mechanical hypersensitivity in the Complete Freund’s Adjuvant (CFA model for up to 2 h post-injection. The 15d-PGJ2-mediated reduction in mechanical hypersensitivity is dependent on TRPA1, as this effect was absent in TRPA1 knockout mice. Ca2+ imaging studies of DRG neurons demonstrated that 15d-PGJ2 pre-exposure reduced the magnitude and number of neuronal responses to AITC, but not CAP. AITC responses were not reduced when neurons were pre-exposed to 15d-PGJ2 combined with HC-030031 (TRPA1 antagonist, demonstrating that inhibitory effects of 15d-PGJ2 depend on TRPA1 activation. Single daily doses of 15d-PGJ2, administered during the course of 4 days in the CFA model, effectively reversed mechanical hypersensitivity without apparent tolerance or toxicity. Conclusions Taken together, our data support the hypothesis that 15d-PGJ2 induces activation followed by persistent inhibition of TRPA1 channels

  19. [Induced abortion using prostaglandin E2 and F2alpha gel].

    Science.gov (United States)

    Lippert, T H; Modly, T

    1974-01-01

    In this study of 20 patients in the 13th-17th week of pregnancy abortion was induced with intrauterine, extraamniotic application of prostaglandins (PG) E2 or F2 in gel form. The gel composition was as follows: 4% tylose MH 300, 2% glycerine, 1% chlorhexidine digluconate, 83% sterile distilled water and 10% PG stock solution. Both PGE2 and PGF2 gels were used. Final concentration was 2.5 mg E2 or 2.5 mg F2 per g of gel. Gel was applied via transcervical, extraamniotic polyethylene catheter every 2-3 hours. Results: PGE2-gel was used in 14 cases. After 3-4 applications both fetus and placenta were expelled. Average dose used was 4.6 mg E2/patient. First contractions started in 30 minutes; induction to expulsion time was 11 hours 35 minutes. F2-gel given to 6 patients resulted in expulsion of the fetus in all cases but placenta needed removal by curettage in 4 patients. Average dose per patient was 17.7 mg of F2; first contractions in 30 minutes, average expulsion time 17 hours 38 minutes. With both PGs there were painful contractions which were controlled with a combination of pentazocine and Valium. PGE2 caused vomiting in 5 patients. No increased bleeding or postabortion infection occurred. Follow-up curettage was done in all patients to ensure removal of all tissues. Overall evaluation of the PG-gels was considered good. PG stability in gel form is good; during 8 months of preservation in sterile aluminum tubes at -25 degrees Celsius no decline in clinical effectiveness was noted. The gel application is less expensive than the slow-injection pump method.

  20. IGFBP-3, hypoxia and TNF-{alpha} inhibit adiponectin transcription

    Energy Technology Data Exchange (ETDEWEB)

    Zappala, Giovanna, E-mail: zappalag@mail.nih.gov [Diabetes Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD (United States); Rechler, Matthew M. [Diabetes Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD (United States); Clinical Endocrinology Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD (United States)

    2009-05-15

    The thiazolidinedione rosiglitazone, an agonist ligand for the nuclear receptor PPAR-{gamma}, improves insulin sensitivity in part by stimulating transcription of the insulin-sensitizing adipokine adiponectin. It activates PPAR-{gamma}-RXR-{alpha} heterodimers bound to PPAR-{gamma} response elements in the adiponectin promoter. Rosiglitazone-stimulated adiponectin protein synthesis in 3T3-L1 mouse adipocytes has been shown to be inhibited by IGFBP-3, which can be induced by hypoxia and the proinflammatory cytokine, TNF-{alpha}, two inhibitors of adiponectin transcription. The present study demonstrates that IGFBP-3, the hypoxia-mimetic agent cobalt chloride, and TNF-{alpha} inhibit rosiglitazone-induced adiponectin transcription in mouse embryo fibroblasts that stably express PPAR-{gamma}2. Native IGFBP-3 can bind RXR-{alpha} and inhibited rosiglitazone stimulated promoter activity, whereas an IGFBP-3 mutant that does not bind RXR-{alpha} did not. These results suggest that IGFBP-3 may mediate the inhibition of adiponectin transcription by hypoxia and TNF-{alpha}, and that IGFBP-3 binding to RXR-{alpha} may be required for the observed inhibition.

  1. Alpha oscillatory correlates of motor inhibition in the aged brain

    Directory of Open Access Journals (Sweden)

    Marlene eBoenstrup

    2015-10-01

    Full Text Available Exerting inhibitory control is a cognitive ability mediated by functions known to decline with age. The goal of this study is to add to the mechanistic understanding of cortical inhibition during motor control in aged brains. Based on behavioral findings of impaired inhibitory control with age we hypothesized that elderly will show a reduced or a lack of EEG alpha-power increase during tasks that require motor inhibition. Since inhibitory control over movements has been shown to rely on prior motor memory formation, we investigated cortical inhibitory processes at two points in time - early after learning and after an overnight consolidation phase and hypothesized an overnight increase of inhibitory capacities. Young and elderly participants acquired a complex finger movement sequence and in each experimental session brain activity during execution and inhibition of the sequence was recorded with multi-channel EEG. We assessed cortical processes of sustained inhibition by means of task-induced changes of alpha oscillatory power. During inhibition of the learned movement, young participants showed a significant alpha power increase at the sensorimotor cortices whereas elderly did not. Interestingly, for both groups, the overnight consolidation phase improved up-regulation of alpha power during sustained inhibition. This points to deficits in the generation and enhancement of local inhibitory mechanisms at the sensorimotor cortices in aged brains. However, the alpha power increase in both groups implies neuroplastic changes that strengthen the network of alpha power generation over time in young as well as elderly brains.

  2. Regulation of pulsatile secretion of prostaglandin F2 alpha from the ovine uterus by ovarian steroids.

    Science.gov (United States)

    Silvia, W J; Raw, R E

    1993-07-01

    Two experiments were conducted to determine how progesterone and oestradiol regulate pulsatile secretion of PGF2 alpha from the ovine uterus. In Expt 1, ovariectomized ewes received: (1) no treatment, (2) oestradiol, (3) progesterone, or (4) oestradiol and progesterone (n = 5 ewes per treatment group) to approximate the changes in steroids that occur during the oestrous cycle. Jugular venous blood samples were collected at 30 min intervals for 48 h beginning at 08:00 on day 14 of steroid replacement. Blood samples were collected from five intact ewes at a comparable time of the oestrous cycle for comparison. The number and magnitude of pulses in 13,14-dihydro-15-keto-PGF2 alpha (PGFM) in jugular venous blood samples were used to assess uterine secretion of PGF2 alpha. Experiment 2 was conducted as Expt 1, except that the progesterone replacement protocol was modified to duplicate more closely the temporal pattern of progesterone observed in intact ewes. Results were similar in both experiments. Intact ewes averaged 4.4 +/- 0.6 pulses per 48 h blood sampling period. The frequency of pulses was less in ovariectomized ewes (P < 0.05). The number of pulses was increased by progesterone treatment (P < 0.01); the number of pulses in ovariectomized ewes receiving progesterone replacement was similar to that observed in intact ewes. There was a tendency for oestradiol to have a positive effect on the number of pulses (P = 0.12). The magnitude of pulses in intact ewes averaged 419 +/- 38 pg ml-1 and was much less in ovariectomized ewes (P < 0.05) than in intact ewes.(ABSTRACT TRUNCATED AT 250 WORDS)

  3. Inhibition of the prostaglandin receptor EP2 following status epilepticus reduces delayed mortality and brain inflammation.

    Science.gov (United States)

    Jiang, Jianxiong; Quan, Yi; Ganesh, Thota; Pouliot, Wendy A; Dudek, F Edward; Dingledine, Raymond

    2013-02-26

    Prostaglandin E2 is now widely recognized to play critical roles in brain inflammation and injury, although the responsible prostaglandin receptors have not been fully identified. We developed a potent and selective antagonist for the prostaglandin E2 receptor subtype EP2, TG6-10-1, with a sufficient pharmacokinetic profile to be used in vivo. We found that in the mouse pilocarpine model of status epilepticus (SE), systemic administration of TG6-10-1 completely recapitulates the effects of conditional ablation of cyclooxygenase-2 from principal forebrain neurons, namely reduced delayed mortality, accelerated recovery from weight loss, reduced brain inflammation, prevention of blood-brain barrier opening, and neuroprotection in the hippocampus, without modifying seizures acutely. Prolonged SE in humans causes high mortality and morbidity that are associated with brain inflammation and injury, but currently the only effective treatment is to stop the seizures quickly enough with anticonvulsants to prevent brain damage. Our results suggest that the prostaglandin receptor EP2 is critically involved in neuroinflammation and neurodegeneration, and point to EP2 receptor antagonism as an adjunctive therapeutic strategy to treat SE.

  4. Combined inhibition of nitric oxide and prostaglandins reduces human skeletal muscle blood flow during exercise

    DEFF Research Database (Denmark)

    Boushel, Robert Christopher; Langberg, Henning; Gemmer, Carsten;

    2002-01-01

    The vascular endothelium is an important mediator of tissue vasodilatation, yet the role of the specific substances, nitric oxide (NO) and prostaglandins (PG), in mediating the large increases in muscle perfusion during exercise in humans is unclear. Quadriceps microvascular blood flow was quanti...

  5. Hyperforin, an anti-inflammatory constituent from St. John’s wort, inhibits microsomal prostaglandin E2 synthase-1 and suppresses prostaglandin E2 formation in vivo

    Directory of Open Access Journals (Sweden)

    Andreas eKoeberle

    2011-02-01

    Full Text Available The acylphloroglucinol hyperforin (Hyp from St. John’s wort possesses anti-inflammatory and anti-carcinogenic properties which were ascribed among others to the inhibition of 5-lipoxygenase. Here, we investigated whether Hyp also interferes with prostanoid generation in biological systems, particularly with key enzymes participating in prostaglandin (PGE2 biosynthesis, i.e., cyclooxygenases (COX-1/2 and microsomal PGE2 synthase (mPGES-1 which play key roles in inflammation and tumorigenesis. Similar to the mPGES-1 inhibitors MK-886 and MD-52, Hyp significantly suppressed PGE2 formation in whole blood assays starting at 0.03 to 1 µM, whereas the concomitant generation of COX-derived 12(S-hydroxy-5-cis-8,10-trans-hepta¬deca¬trienoic acid, thromboxane B2, and 6-keto PGF1α was not significantly suppressed up to 30 µM. In cell-free assays, Hyp efficiently blocked the conversion of PGH2 to PGE2 mediated by mPGES-1 (IC50 = 1 µM, and isolated COX enzymes were not (COX-2 or hardly (COX-1 suppressed. Intraperitoneal (i.p. administration of Hyp (4 mg kg-1 to rats impaired exudate volume and leukocyte numbers in carrageenan-induced pleurisy associated with reduced PGE2 levels, and Hyp (given i.p. inhibited carrageenan-induced mouse paw edema formation (ED50 = 1 mg kg-1 being superior over indomethacin (ED50 = 5 mg kg-1. We conclude that the suppression of PGE2 biosynthesis in vitro and in vivo by acting on mPGES-1 critically contributes to the anti-inflammatory efficiency of Hyp.

  6. Inhibition of Prostaglandin Transporter (PGT Promotes Perfusion and Vascularization and Accelerates Wound Healing in Non-Diabetic and Diabetic Rats.

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    Zhongbo Liu

    Full Text Available Peripheral ischemia, resulting from diminished arterial flow and defective local vascularization, is one of the main causes of impaired wound healing in diabetes. Vasodilatory prostaglandins (PGs, including PGE2 and PGI2, regulate blood flow in peripheral tissues. PGs also stimulate angiogenesis by inducing vascular endothelial growth factor. However, PG levels are reduced in diabetes mainly due to enhanced degradation. We hypothesized that inhibition of the prostaglandin transporter (PGT (SLCO2A1, which mediates the degradation of PGs, would increase blood flow and stimulate vascularization, thereby mitigating peripheral ischemia and accelerating wound healing in diabetes. Here we report that inhibiting PGT with intravenously injected PGT inhibitor, T26A, increased blood flow in ischemic hind limbs created in non-diabetic rats and streptozotocin induced diabetic rats. Systemic, or combined with topical, T26A accelerated closure of cutaneous wounds. Immunohistochemical examination revealed that inhibition of PGT enhanced vascularization (marked by larger numbers of vessels formed by CD34+ cells, and accelerated re-epithelialization of cutaneous wounds. In cultured primary human bone marrow CD34+ cells and human epidermal keratinocytes (HEKs either inhibiting or silencing PGT increased migration in both cell lines. Thus PGT directly regulates mobilization of endothelial progenitor cells (EPCs and HEKs, which could contribute to PGT-mediated vascularization and re-epithelialization. At the molecular level, systemic inhibition of PGT raised circulating PGE2. Taken together, our data demonstrate that PGT modulates arterial blood flow, mobilization of EPCs and HEKs, and vascularization and epithelialization in wound healing by regulating vasodilatory and pro-angiogenic PGs.

  7. Changes in growth and lipid profiles of silk gland, mid-gut biochemical composition of silkworm, Bombyx mori L. on exposure to prostaglandin F2alpha.

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    Miao, Yun-gen; Jiang, Li-jun

    2003-01-01

    The growth of the silkworm is influenced by the outside and inside environment. Among them, the category of various endocrine hormone of inside is the main factors that adjust the characters such as growth and propagate. In this experiment, we applied different dosage of prostaglandin to the fourth and fifth instar silkworm to observe the effects of prostaglandin F2alpha (PGF2alpha) on silk gland growth, mid-gut biochemical constituents and the lipid profiles of silkworm larva, Bombyx mori L. The weight of the posterior silk gland increased significantly (P lipid profiles except lipase activity suggests that the silk gland had more synthetic activity that might reflect in active spinning of silkworm larva. The changes of total proteins, free amino acids and alkaline phosphatase in mid-gut of control and PGF2alpha treated silkworm, B. mori L. indicate that PGF2alpha favored stimulatory effect on physiology of digestion, absorption and transportation of nutrients which might influence on the growth and development of larva.

  8. Cellular mechanisms mediating the stimulation of ovine endometrial secretion of prostaglandin F2 alpha in response to oxytocin: role of phospholipase A2.

    Science.gov (United States)

    Lee, J S; Silvia, W J

    1994-06-01

    Four experiments were conducted to determine whether phospholipase (PL) A2 mediates the stimulatory effect of oxytocin on the release of prostaglandin (PG) F2 alpha from ovine endometrial tissue. Caruncular endometrial tissue was collected from ovariectomized ewes on the day after a steroid replacement protocol had been completed. The replacement protocol consisted of progesterone for 10 days (12 mg/day) followed by oestradiol on days 10 and 11 (100 micrograms/day) and had been shown previously to provide endometrial tissue that would release PGF2 alpha in response to oxytocin in vitro. In experiment 1, oxytocin (10(-7) M) and melittin (1.76 x 10(-6) M; a stimulator of PLA2) stimulated release of PGF2 alpha from tissue explants (P 80% (P < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

  9. Pharmacological inhibition of microsomal prostaglandin E synthase-1 suppresses epidermal growth factor receptor-mediated tumor growth and angiogenesis.

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    Federica Finetti

    Full Text Available BACKGROUND: Blockade of Prostaglandin (PG E(2 production via deletion of microsomal Prostaglandin E synthase-1 (mPGES-1 gene reduces tumor cell proliferation in vitro and in vivo on xenograft tumors. So far the therapeutic potential of the pharmacological inhibition of mPGES-1 has not been elucidated. PGE(2 promotes epithelial tumor progression via multiple signaling pathways including the epidermal growth factor receptor (EGFR signaling pathway. METHODOLOGY/PRINCIPAL FINDINGS: Here we evaluated the antitumor activity of AF3485, a compound of a novel family of human mPGES-1 inhibitors, in vitro and in vivo, in mice bearing human A431 xenografts overexpressing EGFR. Treatment of the human cell line A431 with interleukin-1beta (IL-1β increased mPGES-1 expression, PGE(2 production and induced EGFR phosphorylation, and vascular endothelial growth factor (VEGF and fibroblast growth factor-2 (FGF-2 expression. AF3485 reduced PGE(2 production, both in quiescent and in cells stimulated by IL-1β. AF3485 abolished IL-1β-induced activation of the EGFR, decreasing VEGF and FGF-2 expression, and tumor-mediated endothelial tube formation. In vivo, in A431 xenograft, AF3485, administered sub-chronically, decreased tumor growth, an effect related to inhibition of EGFR signalling, and to tumor microvessel rarefaction. In fact, we observed a decrease of EGFR phosphorylation, and VEGF and FGF-2 expression in tumours explanted from treated mice. CONCLUSION: Our work demonstrates that the pharmacological inhibition of mPGES-1 reduces squamous carcinoma growth by suppressing PGE(2 mediated-EGFR signalling and by impairing tumor associated angiogenesis. These results underscore the potential of mPGES-1 inhibitors as agents capable of controlling tumor growth.

  10. Terameprocol, a methylated derivative of nordihydroguaiaretic acid, inhibits production of prostaglandins and several key inflammatory cytokines and chemokines

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    Scholle F

    2009-01-01

    Full Text Available Abstract Background Extracts of the creosote bush, Larrea tridentata, have been used for centuries by natives of western American and Mexican deserts to treat a variety of infectious diseases and inflammatory disorders. The beneficial activity of this plant has been linked to the compound nordihydroguaiaretic acid (NDGA and its various substituted derivatives. Recently, tetra-O-methyl NDGA or terameprocol (TMP has been shown to inhibit the growth of certain tumor-derived cell lines and is now in clinical trials for the treatment of human cancer. In this report, we ask whether TMP also displays anti-inflammatory activity. TMP was tested for its ability to inhibit the LPS-induced production of inflammatory lipids and cytokines in vitro. We also examined the effects of TMP on production of TNF-α in C57BL6/J mice following a sublethal challenge with LPS. Finally, we examined the molecular mechanisms underlying the effects we observed. Methods RAW 264.7 cells and resident peritoneal macrophages from C57BL6/J mice, stimulated with 1 μg/ml LPS, were used in experiments designed to measure the effects of TMP on the production of prostaglandins, cytokines and chemokines. Prostaglandin production was determined by ELISA. Cytokine and chemokine production were determined by antibody array and ELISA. Western blots, q-RT-PCR, and enzyme assays were used to assess the effects of TMP on expression and activity of COX-2. q-RT-PCR was used to assess the effects of TMP on levels of cytokine and chemokine mRNA. C57BL6/J mice injected i.p. with LPS were used in experiments designed to measure the effects of TMP in vivo. Serum levels of TNF-α were determined by ELISA. Results TMP strongly inhibited the production of prostaglandins from RAW 264.7 cells and normal peritoneal macrophages. This effect correlated with a TMP-dependent reduction in levels of COX-2 mRNA and protein, and inhibition of the enzymatic activity of COX-2. TMP inhibited, to varying degrees, the

  11. Cellular mechanisms mediating the stimulation of ovine endometrial secretion of prostaglandin F2 alpha in response to oxytocin: role of phospholipase C and diacylglycerol.

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    Silvia, W J; Lee, J S; Trammell, D S; Hayes, S H; Lowberger, L L; Brockman, J A

    1994-06-01

    The first objective was to describe and evaluate the relationship between the ability of oxytocin to stimulate the activity of phospholipase (PL) C and its ability to stimulate the release of prostaglandin (PG) F2 alpha in ovine endometrial tissue. Caruncular endometrial tissue was collected from ovariectomized ewes after completion of an 11-day steroid replacement protocol. In experiment 1, explants were incubated either in the presence (10(-6) M) or absence of oxytocin for 0, 1, 3, 10, 30 or 100 min to examine the time-course for activation of PLC and release of PGF2 alpha in response to oxytocin. An increase in the activity of PLC was detected at 3 min while an increase in the release of PGF2 alpha was not detected until 10 min (P 0.1). Based on the results from these experiments, the role of PLC in mediating the stimulatory effect of oxytocin on the release of PGF2 alpha remains unclear. The second objective was to evaluate the role of diacylglycerol (DAG) in mediating the stimulatory effect of oxytocin on endometrial secretion of PGF2 alpha. In experiment 5, explants were incubated in vitro with varying doses of two DAG analogues.(ABSTRACT TRUNCATED AT 250 WORDS)

  12. Suppression of prostaglandin E2 receptor subtype EP2 by PPARgamma ligands inhibits human lung carcinoma cell growth.

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    Han, ShouWei; Roman, Jesse

    2004-02-20

    Prostaglandin E(2) (PGE(2)), a major cyclooxygenase (COX-2) metabolite, plays important roles in tumor biology and its functions are mediated through one or more of its receptors EP1, EP2, EP3, and EP4. We have shown that the matrix glycoprotein fibronectin stimulates lung carcinoma cell proliferation via induction of COX-2 expression with subsequent PGE(2) protein biosynthesis. Ligands of peroxisome proliferator-activated receptor gamma (PPARgamma) inhibited this effect and induced cellular apoptosis. Here, we explore the role of the PGE(2) receptor EP2 in this process and whether the inhibition observed with PPARgamma ligands is related to effects on this receptor. We found that human non-small cell lung carcinoma cell lines (H1838 and H2106) express EP2 receptors, and that the inhibition of cell growth by PPARgamma ligands (GW1929, PGJ2, ciglitazone, troglitazone, and rosiglitazone [also known as BRL49653]) was associated with a significant decrease in EP2 mRNA and protein levels. The inhibitory effects of BRL49653 and ciglitazone, but not PGJ2, were reversed by a specific PPARgamma antagonist GW9662, suggesting the involvement of PPARgamma-dependent and -independent mechanisms. PPARgamma ligand treatment was associated with phosphorylation of extracellular regulated kinase (Erk), and inhibition of EP2 receptor expression by PPARgamma ligands was prevented by PD98095, an inhibitor of the MEK-1/Erk pathway. Butaprost, an EP2 agonist, like exogenous PGE(2) (dmPGE(2)), increased lung carcinoma cell growth, however, GW1929 and troglitazone blocked their effects. Our studies reveal a novel role for EP2 in mediating the proliferative effects of PGE(2) on lung carcinoma cells. PPARgamma ligands inhibit human lung carcinoma cell growth by decreasing the expression of EP2 receptors through Erk signaling and PPARgamma-dependent and -independent pathways.

  13. Effects of progesterone and estradiol-17 beta on uterine secretion of prostaglandin F2 alpha in response to oxytocin in ovariectomized ewes.

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    Homanics, G E; Silvia, W J

    1988-05-01

    Twenty ovariectomized ewes were used in an experiment designed to examine the interaction of progesterone, estradiol, and oxytocin in the regulation of uterine secretion of prostaglandin F2 alpha (PGF2 alpha). All ewes underwent a steroid pretreatment that mimicked the changes in progesterone and estradiol which occur during the six days immediately prior to estrus. After pretreatment, ewes were randomly assigned to 1 of 4 treatment groups: 1) control (n = 4); 2) estradiol-17 beta (n = 6); 3) progesterone (n = 4); and 4) progesterone and estradiol-17 beta (n = 6). Progesterone was injected twice daily for 15 days. The dose of progesterone varied with day postestrus in a manner designed to simulate endogenous luteal secretion of progesterone. Estradiol-17 beta was administered in s.c. Silastic implants. The implants maintained circulating concentrations of estradiol at 3 pg/ml. On Days 5, 10, and 15 of treatment, ewes were injected with oxytocin (10 IU in 1.0 ml saline, i.v.). Jugular venous blood samples were collected beginning one-half hour prior to and continuing for 2 hours post-oxytocin injection for quantification of 13,14-dihydro-15-keto-prostaglandin F2 alpha (PGFM). No changes in concentration of PGFM following injection of oxytocin were observed on Day 5 or 10 in any treatment group. Concentrations of PGFM increased following injection of oxytocin on Day 15 only in groups receiving progesterone. Both the area under the PGFM response curve (p = 0.08) and peak response (p = 0.06) were greater in ewes treated with progesterone and estradiol-17 beta than in those receiving progesterone alone.(ABSTRACT TRUNCATED AT 250 WORDS)

  14. Cervical ripening with intracervical prostaglandin-E2 gel. I. Clinical results and effect on plasma levels of oxytocin and 13,14-dihydro,15-ketoprostaglandin-F2 alpha.

    Science.gov (United States)

    Fuchs, A R; Goeschen, K; Rasmussen, A B; Rehnström, J V; Saling, E; Fuchs, F

    1983-10-01

    Tylose gel containing 400 micrograms prostaglandin E2 in 3 ml gel was injected into the cervical canal of 20 patients with high-risk pregnancy and indication for induction of labor, but with unfavorable cervix. Ten were studied after the first gel application, five during repeat injection, and five after application of gel without PGE2. Blood samples were drawn serially during the first 8 hours for determination of oxytocin and 13,14-dihydro,15-ketoprostaglandin-F2 alpha (PGFM). The PGE2 gel increased the Bishop score within 8 hours in all patients; in half of them, artificial rupture of the membranes could be performed and labor induced without further gel application; in the others, it was repeated every 8 hours until a Bishop score of greater than or equal to 8 was achieved. Fourteen of the 15 PGE2-induced patients delivered vaginally. Mean PGFM levels did not increase significantly during the 8 hours of observation, but in patients who responded with rapid progression, an increase was seen after cervical dilation was 6 cm or more. The mean oxytocin levels increased within 60 minutes after PGE2 application and were increased for the remaining observation period. Application of inactive gel had no effect on cervical ripening nor on oxytocin or PGFM levels.

  15. Concentrations of oxytocin in the intercavernous sinus of mares during luteolysis: temporal relationship with concentrations of 13,14-dihydro-15-keto-prostaglandin F2 alpha.

    Science.gov (United States)

    Vanderwall, D K; Silvia, W J; Fitzgerald, B P

    1998-03-01

    The reproductive tracts of nine thoroughbred mares were examined by ultrasound to determine the day of ovulation (day 0). Mares were fitted with intercavernous sinus cannulae on the day before the start of sample collection of pituitary venous effluent rich in oxytocin. Intercavernous sinus blood samples were collected for at least 36 h at 5 min intervals beginning at noon on day 13 (n = 2), day 15 (n = 5) or day 16 (n = 2) after ovulation. Concentrations of oxytocin and 13,14-dihydro-15-keto prostaglandin F2 alpha (PGFM) in plasma were determined by radioimmunoassay. Three high-magnitude surges of PGFM (> 1 ng ml-1) were found in these samples. Three high magnitude pulses of oxytocin (> 200 pg ml-1) were also observed, one associated with each of the PGFM surges. In each of these cases, the oxytocin pulse appeared to follow or coincide with the onset of the PGFM surge. Lower magnitude pulses of both hormones were detected throughout the bleeding period in every mare. The average interval between these pulses was 122.3 min for oxytocin and 121.0 min for PGFM. The interval between pulses for individual mares varied from 90 to 199 min for oxytocin, and from 87 to 213 min for PGFM. However, there was no correlation between PGFM and oxytocin pulse intervals among mares. Within each mare, there was no discernable association between low magnitude pulses of oxytocin and PGFM. From these data, it was concluded that high-magnitude surges of PGF2 alpha are associated with similar surges of oxytocin from the posterior pituitary gland, and that PGF2 alpha may induce their secretion. The posterior pituitary gland also appears to secrete oxytocin in a pulsatile manner at a frequency of approximately 1 pulse every 2 h but these pulses do not appear to be associated with the low magnitude pulses of PGF2 alpha secreted from the uterus.

  16. Uterine secretion of prostaglandin F2 alpha in response to oxytocin in ewes: changes during the estrous cycle and early pregnancy.

    Science.gov (United States)

    Silvia, W J; Raw, R E; Aldrich, S L; Hayes, S H

    1992-06-01

    Experiment 1 was conducted to determine when the ovine uterus develops the ability to secrete prostaglandin F2 alpha (PGF2 alpha) in response to oxytocin and how development is affected by pregnancy. Pregnant and nonpregnant ewes received an injection of oxytocin (10 IU, i.v.) on Day 10, 13, or 16 postestrus. Jugular venous blood samples were collected for 2 h after injection for quantification of 13,14-dihydro-15-keto-PGF2 alpha (PGFM). In nonpregnant ewes, concentrations of PGFM increased following oxytocin on Day 16 but not on Day 10 or 13. Concentrations of PGFM did not increase following treatment on Day 10, 13, or 16 in pregnant ewes. Therefore, the ability of oxytocin to induce uterine secretion of PGF2 alpha develops after Day 13 in nonpregnant but not in pregnant ewes. Experiment 2 was conducted to precisely define when uterine secretory responsiveness to oxytocin develops. Pregnant and nonpregnant ewes received oxytocin on Day 12, 13, 14, or 15. In nonpregnant ewes, concentrations of PGFM increased following treatment on Days 14 and 15, but not earlier. Peripheral concentrations of progesterone showed that uterine secretory responsiveness to oxytocin developed prior to the onset of luteal regression. As in experiment 1, the increase in concentrations of PGFM following administration of oxytocin was much lower in pregnant than in nonpregnant ewes; however, some pregnant ewes did respond to oxytocin with an increase in PGFM. In experiment 3, pregnant ewes received an injection of oxytocin on Day 18, 24, or 30 postmating. Concentrations of PGFM increased following oxytocin on Days 18 and 24. The conceptus appears to delay and attenuate the development of uterine secretory responsiveness to oxytocin.

  17. Effects of prostaglandin F2 alpha and a gonadotropin-releasing hormone agonist on inositol phospholipid metabolism in isolated rat corpora lutea of various ages

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    Lahav, M.; West, L.A.; Davis, J.S.

    1988-08-01

    The sensitivity of rat corpora lutea to luteolytic agents increases with luteal age. We examined the effect of prostaglandin F2 alpha (PGF2 alpha) and (D-Ala6,Des-Gly10)GnRH ethylamide (GnRHa) on inositol phospholipid metabolism in day 2 and day 7 corpora lutea from PMSG-treated rats. Isolated corpora lutea were incubated with 32PO4 or (3H)inositol and were treated with LH, PGF2 alpha, or GnRHa. Phospholipids were purified by TLC, and the water-soluble products of phospholipase-C activity (inositol phosphates) were isolated by ion exchange chromatography. In day 2 corpora lutea, PGF2 alpha, (10 microM) and GnRHa (100 ng/ml) significantly increased 32PO4 incorporation into phosphatidic acid (PA) and phosphatidylinositol (PI), but not into other fractions. LH provoked slight increases in PA. Results were similar with 30 min of prelabeling or simultaneous addition of 32PO4 and stimulants. In other experiments, PGF2 alpha and GnRHa provoked rapid increases (1-5 min) in the accumulation of inositol mono-, bis-, and trisphosphates. LH did not significantly increase inositol phosphate accumulation, but stimulated cAMP accumulation in 2-day-old corpora lutea. Inositol phospholipid metabolism was increased in day 7 corpora lutea compared to that in day 2 corpora lutea. This increase was associated with increased incorporation of 32PO4 into PA and PI and increased accumulation of (3H)inositol phosphates. In day 7 corpora lutea, which are very sensitive to the luteolytic effect of PGF2 alpha, the PG-induced increase in PA labeling was small and inconsistent, whereas PI labeling was unaffected in 30-min incubations. GnRHa was without effect in such corpora lutea. LH, PGF2 alpha, or GnRHa did not increase inositol phosphate accumulation in 7-day-old corpora lutea. These studies demonstrate that the transformation of young (day 2) to mature (day 7) corpora lutea is associated with an increase in luteal inositol phospholipid metabolism.

  18. Cellular mechanisms by which oxytocin mediates ovine endometrial prostaglandin F2alpha synthesis: role of G(i) proteins and mitogen-activated protein kinases.

    Science.gov (United States)

    Burns, P D; Mendes, J O; Yemm, R S; Clay, C M; Nelson, S E; Hayes, S H; Silvia, W J

    2001-10-01

    Oxytocin stimulates a rapid increase in ovine endometrial prostaglandin (PG) F2alpha synthesis. The overall objective of these experiments was to investigate the cellular mechanisms by which oxytocin induces endometrial PGF2alpha synthesis. The objective of experiment 1 was to determine whether G(i) proteins mediate oxytocin-induced PGF2alpha synthesis. Uteri were collected from four ovary-intact ewes on Day 14 postestrus. Caruncular endometrial explants were dissected and subjected to in vitro incubation. Pertussis toxin, an inhibitor of G(i) proteins, had no effect on the ability of oxytocin to induce PGF2alpha synthesis (P > 0.10). The objective of experiment 2 was to determine whether any of the three mitogen-activated protein kinases (MAPKs), extracellular signal regulated protein kinase (ERK1/2), c-Jun N-terminal/stress-activated protein kinase (JNK/SAPK), or p38 MAPK, mediate oxytocin-induced PGF(2alpha) synthesis. Eleven ovary-intact ewes were given an injection of oxytocin (10 IU; i.v.; n = 5) or physiological saline (i.v.; n = 6) on Day 15 postestrus. Uteri were collected 15 min after injection and caruncular endometrium was dissected. Endometrial homogenates were prepared and subjected to Western blotting. Membranes were probed for both total and phosphorylated forms of all three classes of MAPK. All classes of MAPK were detected in ovine endometrium, but oxytocin treatment had no effect on the expression of these proteins (P > 0.10). ERK1/2 was the only phosphorylated MAPK detected and its concentrations were higher in oxytocin-treated ewes (P Day 14 postestrus. Caruncular endometrial explants were dissected and subjected to in vitro incubation. PD98059, a specific inhibitor of ERK1/2 activity, blocked the ability of oxytocin to stimulate PGF(2alpha synthesis in a dose-dependent manner (P < 0.05). These results indicate that the ovine oxytocin receptor is not coupled to G(i) proteins. These results indicate that oxytocin induces phosphorylation of ERK1

  19. Effect of sodium loading on the urinary excretion of prostaglandins E2 and F2 alpha in rats with hereditary diabetes insipidus (Brattleboro rats).

    Science.gov (United States)

    Rathaus, M; Kariv, N; Shapira, J; Bernheim, J

    1985-01-01

    Current evidence suggests that the antidiuretic hormone (ADH) and changes in sodium balance influence renal prostaglandins (PGs). To separate these two mechanisms, the effect of sodium loading on the urinary excretion of PGE2 and PGF2 alpha was studied in female Brattleboro rats with diabetes insipidus (DIHO) and compared with that in female, age matched, heterozygous Long Evans controls (LEHE). Ten DIHO and ten LEHE rats had a normal sodium intake. In ten DIHO rats a 0.16% NaCl solution was supplied instead of drinking water for either 8 days (n = 5) or 14 days (n = 5). In two groups of LEHE rats, sodium loading was obtained with a 0.80% NaCl solution for the same study periods. Urine PGs were measured by radioimmunoassay in three 24 h urine collections for each rat. Urine PGs were significantly increased in the 8 day loaded but not in the 14 day loaded LEHE rats. In DIHO rats, a non-significant increase in both PGE2 and PGF2 alpha was present after 8 days of sodium loading, while PGE2 and the E/F ratio were decreased after 14 days of salt loading. The findings suggest that the natriuresis induced by sodium loading in the rat may be mediated in part by increased production of PGs. In addition, it seems that ADH plays a role in this response.

  20. Modulation of phenytoin teratogenicity and embryonic covalent binding by acetylsalicylic acid, caffeic acid, and alpha-phenyl-N-t-butylnitrone: implications for bioactivation by prostaglandin synthetase

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    Wells, P.G.; Zubovits, J.T.; Wong, S.T.; Molinari, L.M.; Ali, S.

    1989-02-01

    Teratogenicity of the anticonvulsant drug phenytoin is thought to involve its bioactivation by cytochromes P-450 to a reactive arene oxide intermediate. We hypothesized that phenytoin also may be bioactivated to a teratogenic free radical intermediate by another enzymatic system, prostaglandin synthetase. To evaluate the teratogenic contribution of this latter pathway, an irreversible inhibitor of prostaglandin synthetase, acetylsalicylic acid (ASA), 10 mg/kg intraperitoneally (ip), was administered to pregnant CD-1 mice at 9:00 AM on Gestational Days 12 and 13, 2 hr before phenytoin, 65 mg/kg ip. Other groups were pretreated 2 hr prior to phenytoin administration with either the antioxidant caffeic acid or the free radical spin trapping agent alpha-phenyl-N-t-butylnitrone (PBN). Caffeic acid and PBN were given ip in doses that respectively were up to 1.0 to 0.05 molar equivalents to the dose of phenytoin. Dams were killed on Day 19 and the fetuses were assessed for teratologic anomalies. A similar study evaluated the effect of ASA on the in vivo covalent binding of radiolabeled phenytoin administered on Day 12, in which case dams were killed 24 hr later on Day 13. ASA pretreatment produced a 50% reduction in the incidence of fetal cleft palates induced by phenytoin (p less than 0.05), without significantly altering the incidence of resorptions or mean fetal body weight. Pretreatment with either caffeic acid or PBN resulted in dose-related decreases in the incidence of fetal cleft palates produced by phenytoin, with maximal respective reductions of 71 and 82% at the highest doses of caffeic acid and PBN (p less than 0.05).

  1. Alpha 1-antitrypsin does not inhibit human monocyte caspase-1.

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    Mohd Akhlakur Rahman

    Full Text Available Alpha 1-antitrypsin (A1AT is a 52 kDa serine protease inhibitor produced largely by hepatocytes but also by mononuclear phagocytes. A1AT chiefly inhibits neutrophil elastase and proteinase-3 but has also been reported to have immune modulatory functions including the ability to inhibit caspases. Its clinical availability for infusion suggests that A1AT therapy might modulate caspase related inflammation. Here we tested the ability of A1AT to modulate caspase-1 function in human mononuclear phagocytes.Purified plasma derived A1AT was added to active caspase-1 in a cell-free system (THP-1 lysates as well as added exogenously to cell-culture models and human whole blood models of caspase-1 activation. Functional caspase-1 activity was quantified by the cleavage of the caspase-1 specific fluorogenic tetrapeptide substrate (WEHD-afc and the release of processed IL-18 and IL-1β.THP-1 cell lysates generated spontaneous activation of caspase-1 both by WEHD-afc cleavage and the generation of p20 caspase-1. A1AT added to this cell free system was unable to inhibit caspase-1 activity. Release of processed IL-18 by THP-1 cells was also unaffected by the addition of exogenous A1AT prior to stimulation with LPS/ATP, a standard caspase-1 activating signal. Importantly, the A1AT exhibited potent neutrophil elastase inhibitory capacity. Furthermore, A1AT complexed to NE (and hence conformationally modified also did not affect THP-1 cell caspase-1 activation. Finally, exogenous A1AT did not inhibit the ability of human whole blood samples to process and release IL-1β.A1AT does not inhibit human monocyte caspase-1.

  2. Maintenance of the corpus luteum of early pregnancy in the ewe. IV. Changes in luteal sensitivity to prostaglandin F2 alpha throughout early pregnancy.

    Science.gov (United States)

    Silvia, W J; Niswender, G D

    1986-10-01

    Two experiments were conducted to examine the temporal aspects of luteal resistance to the luteolytic effect of prostaglandin (PG) F2 alpha during early pregnancy. In Exp. 1, 14 pregnant and 12 nonpregnant ewes were treated with PGF2 alpha either on d 10 or 13 post-estrus. Jugular venous blood samples were collected at -30 min, 0, 6, 12, 18, 24, 30 and 36 h post-injection for quantification of progesterone. The difference (delta P) between pre-treatment and post-treatment concentrations of progesterone was calculated for each ewe. There was a significant interaction between pregnancy status and day of treatment on delta P (P less than .05). Pregnant and nonpregnant ewes treated on d 10 showed a large delta P. A large delta P also was observed in nonpregnant ewes treated on d 13 post-estrus. However, delta P in pregnant ewes treated on d 13 was smaller than in the other three groups (P less than .05). The temporal patterns of concentrations of progesterone in serum were different among treatment groups (P less than .05). A suppression in the concentration of progesterone was observed by 24 h post-injection in all four treatment groups. Progesterone returned to pre-treatment levels only in pregnant ewes treated on d 13. In Exp. 2, 47 pregnant ewes were treated with PGF2 alpha on d 10, 13, 16, 19, 22, 26 or 30 postestrus. Blood samples were collected and data were analyzed as described for Exp. 1.(ABSTRACT TRUNCATED AT 250 WORDS)

  3. [Changes in prostaglandin systhetase activity in mouse tissues as affected by S-[N-(3-aminopropyl)-2-aminoethyl] thiophosphoric acid].

    Science.gov (United States)

    Prianishnikova, E N; Zhulanova, Z I; Romantsev, E F

    1980-01-01

    Effect of various concentrations of a radioprotector S-[N-(3 aminopropyl)-2-aminoethyl] thiophosphoric acid on the activity of prostaglandine synthetase was studied in mouse liver microsomes as well as in the soluble fractions of testicules and brain in vitro. The activity of prostaglandine synthetase was estimated by monitoring the formation of labelled PGF2 alpha and PGE2 from I-14C-arachidonic acid. The radioprotector at concentration 1.66 mg/ml stimulated formation of PGF2 alpha in all the tissues studied. At the lower concentrations of the radioprotector only slight stimulation of the biosynthesis of prostaglandines in testicules was noted. No effect on their synthesis in the brain soluble fraction could be observed while in the liver microsomes it was inhibited. The radioprotective substance studied apparently affected the cyclooxygenase activity, which is a key enzyme in the prostaglandine-synthesizing system.

  4. Subliminal unconscious conflict alpha power inhibits supraliminal conscious symptom experience

    Directory of Open Access Journals (Sweden)

    Howard eShevrin

    2013-09-01

    Full Text Available Our approach is based on a tri-partite method of integrating psychodynamic hypotheses, cognitive subliminal processes, and psychophysiological alpha power measures. We present ten social phobic subjects with three individually selected groups of words representing unconscious conflict, conscious symptom experience, and Osgood Semantic negative valence words used as a control word group. The unconscious conflict and conscious symptom words, presented subliminally and supraliminally, act as primes preceding the conscious symptom and control words presented as supraliminal targets. With alpha power as a marker of inhibitory brain activity, we show that unconscious conflict primes, only when presented subliminally, have a unique inhibitory effect on conscious symptom targets. This effect is absent when the unconscious conflict primes are presented supraliminally, or when the target is the control words. Unconscious conflict prime effects were found to correlate with a measure of repressiveness in a similar previous study (Shevrin et al., 1992, 1996. Conscious symptom primes have no inhibitory effect when presented subliminally. Inhibitory effects with conscious symptom primes are present, but only when the primes are supraliminal, and they did not correlate with repressiveness in a previous study (Shevrin, et al., 1992, 1996. We conclude that while the inhibition following supraliminal conscious symptom primes is due to conscious threat bias, the inhibition following subliminal unconscious conflict primes provides a neurological blueprint for dynamic repression: it is only activated subliminally by an individual’s unconscious conflict and has an inhibitory effect specific only to the conscious symptom. These novel findings constitute neuroscientific evidence for the psychoanalytic concepts of unconscious conflict and repression, while extending neuroscience theory and methods into the realm of personal, psychological meaning.

  5. 15-Deoxy-Delta12,14-prostaglandin J2 modifies components of the proteasome and inhibits inflammatory responses in human endothelial cells

    Directory of Open Access Journals (Sweden)

    Simone Marcone

    2016-10-01

    Full Text Available 15-Deoxy-delta12,14-prostaglandin J2 (15d-PGJ2 is an electrophilic lipid mediator derived from PGD2 with potent anti-inflammatory effects. These are likely to be due to the covalent modification of cellular proteins, via a reactive α,β-unsaturated carbonyl group in its cyclopentenone ring. This study was carried out to identify novel cellular target(s for covalent modification by 15d-PGJ2 and to investigate the anti-inflammatory effects of the prostaglandin on endothelial cells. The data presented here show that 15d-PGJ2 modifies and inhibits components of the proteasome and consequently inhibits the activation of the NF-kB pathway in response to TNF-a. This, in turn, inhibits the adhesion and migration of monocytes toward activated endothelial cells, by reducing the expression of adhesion molecules and chemokines in the endothelial cell. The effects are consistent with the covalent modification of 13 proteins in the 19S particle of the proteasome identified by mass spectrometry and the suppression of proteasome function, and were similar to the effects seen with a known proteasome inhibitor (MG132. The ubiquitin-proteasome system has been implicated in the regulation of several inflammatory processes and the observation that 15d-PGJ2 profoundly affects the proteasome functions in human endothelial cell suggests that 15d-PGJ2 may regulate the progression of inflammatory disorders such as atherosclerosis.

  6. Effects of progesterone and estradiol on uterine secretion of prostaglandin f(2alpha)in response to oxytocin in ovariectomized sows.

    Science.gov (United States)

    Edgerton, L A; Kaminski, M A; Silvia, W J

    2000-02-01

    Thirty ovariectomized sows were used in an experiment designed to determine whether the ability of the porcine uterus to release prostaglandin (PG) F(2alpha) in response to oxytocin is regulated by progesterone (P(4)) and estradiol (E(2)). Sows were assigned to one of four treatment groups: 1) no steroids (ovariectomized controls; n = 8), 2) E(2) (n = 8), 3) P(4) (n = 7), or 4) E(2) + P(4) (n = 7). P(4) and E(2) were administered so as to mimic the normal temporal changes that occur in these hormones during the estrous cycle. A group of intact sows (n = 9) was included for comparison. All sows received an injection of oxytocin (30 IU, i.v.) on Days 12, 15, and 18 postestrus. Jugular venous blood samples were collected from 60 min before through 120 min after injection of oxytocin for quantification of 13,14-dihydro-15-keto-PGF(2alpha) (PGFM). Preinjection baseline concentrations of PGFM, the magnitude of the PGFM response above baseline, and area under the PGFM response curve (AUC) were calculated for each sow on each day and compared among treatment groups by ANOVA. Among the ovariectomized sows receiving steroid replacement, baseline concentrations of PGFM were low on Day 12 postestrus in all four groups. On Days 15 and 18, baseline concentrations remained low in the two groups that did not receive P(4) but increased in those that did. Both the magnitude of the response to oxytocin and AUC were small on Day 12 postestrus in all 4 groups. By Day 15, the magnitude of the response and AUC increased in the group that received both P(4) and E(2) but remained low in the other three groups. By Day 18, responses to oxytocin were greater in both groups that received P(4) than in those that did not. Baseline concentrations were similar in intact sows and in those that received both P(4) and E(2) on all three days examined. The magnitude of the response and the AUC were greater in the ovariectomized sows receiving P(4) and E(2) replacement than in the intact control sows on

  7. Inhibition of human plasma and serum butyrylcholinesterase (EC 3.1.1.8) by alpha-chaconine and alpha-solanine.

    Science.gov (United States)

    Nigg, H N; Ramos, L E; Graham, E M; Sterling, J; Brown, S; Cornell, J A

    1996-10-01

    The purpose of these experiments was to determine the reversibility of alpha-chaconine and alpha-solanine inhibition of human plasma butyrylcholinesterase (BuChE). For the substrate alpha-naphthylacetate, optimal assay conditions were 0.50 M sodium phosphate buffer and a substrate concentration of 3-5 x 10(-4) M. Dibucaine (1 x 10(-5) M) indicated the usual phenotype for all subjects; alpha-chaconine and alpha-solanine at 2.88 x 10(-6) M inhibited BuChE about 70 and 50%, respectively. One- and 24-hr incubations at 1 x 10(-5) M with alpha-chaconine, alpha-solanine, paraoxon, eserine, and ethanol yielded reversible inhibition with dilution except for paraoxon. Twenty-four-hour dialyses of incubations showed no inhibition except for paraoxon. PAGE enzyme activity gels of 1- and 24-hr incubations also showed no inhibition except for paraoxon. alpha-Chaconine and alpha-solanine are reversible inhibitors of human butyrylcholinesterase. At estimated tissue levels, alpha-chaconine, alpha-solanine, and solanidine inhibited BuChE 10-86%. In assays which combined alpha-chaconine, alpha-solanine, and solanidine, inhibition of BuChE was less than additive. No inhibition of albumin alpha-naphthylacetate esterase (an arylesterase) was noted with any inhibitor. The importance of these data to adverse toxicological effects of potato alkaloids is discussed.

  8. Irradiation of human skin by short wavelength ultraviolet radiation (100--290 nm) (u.v.C): increased concentrations of arachidonic acid and prostaglandines E2 and F2alpha.

    Science.gov (United States)

    Camp, R D; Greaves, M W; Hensby, C N; Plummer, N A; Warin, A P

    1978-08-01

    1. Human abdominal skin was irradiated with six times the minimal erythema dose of ultraviolet C (100--290 nm) radiation. Erythema appeared at 3 h, was of moderate degree by 6 h and was maximal at 12--24 h. It was reduced at 48 h and by 72 h had disappeared. 2. A suction bulla technique was used for the recovery of exudate from normal and inflamed skin at 6, 18, 24 and 48 h after irradiation. 3. Prostaglandin-like activity, estimated by bioassay, showed maximum increase at 18 h, when erythema was also maximum. PGF 2alpha, measured by both radioimmunoassay and by combined gas-liquid chromatography--gas spectrometry, followed a similar time course then fell to normal, or near normal, levels at 48 h. 4. Prostaglandin E2 and arachidonic acid concentrations, measured by gas chromatography--mass spectrometry, were maximally raised at 18--24 h. At 48 h, when some erythema was still present, though reduced, prostaglandin E2 concentrations were still raised above control values. 5. The results provide direct evidence in support of the view that the erythma following irradiation of human skin by u.v.C involves activation of arachidonic acid metabolism. However, the relationship between the erythema and increased prostaglandin activity is not fully understood.

  9. On the mechanism of inhibition of p27 degradation by 15-deoxy-Delta12,14-prostaglandin J2 in lymphoblasts of Alzheimer's disease patients.

    Science.gov (United States)

    Muñoz, U; Bartolomé, F; Esteras, N; Bermejo-Pareja, F; Martín-Requero, A

    2008-11-01

    It has been proposed that neuroinflammation, among other factors, may trigger an aberrant neuronal cell cycle re-entry leading to neuronal death. Cell cycle disturbances are also detectable in peripheral cells from Alzheimer's disease (AD) patients. We previously reported that the anti-inflammatory 15- deoxy-Delta(12,14)-prostaglandin J (2) (15d-PGJ (2)) increased the cellular content of the cyclin-dependent kinase inhibitor p27, in lymphoblasts from AD patients. This work aimed at elucidating the mechanisms of 15d-PGJ (2)-induced p27 accumulation. Phosphorylation, half-life, and the nucleo-cytoplasmic traffic of p27 protein were altered by 15d-PGJ2 by mechanisms dependent on PI3K/Akt activity. 15d-PGJ (2) prevents the calmodulin-dependent Akt overactivation in AD lymphoblasts by blocking its binding to the 85-kDa regulatory subunit of PI3K. These effects of 15d-PGJ (2) were not mimicked by 9,10-dihydro-15-deoxy-Delta(12,14)- prostaglandin J (2), suggesting that 15d-PGJ (2) acts independently of peroxisome proliferator-activated receptor gamma activation and that the alpha,beta-unsaturated carbonyl group in the cyclopentenone ring of 15d-PGJ (2) is a requisite for the observed effects.

  10. Induction of heat-shock protein 70 by prostaglandin A₁ inhibits HIV-1 Vif-mediated degradation of APOBEC3G.

    Science.gov (United States)

    Sugiyama, Ryuichi; Abe, Makoto; Nishitsuji, Hironori; Murakami, Yuko; Takeuchi, Hiroaki; Takaku, Hiroshi

    2013-09-01

    Previous studies have demonstrated that cyclopentenone prostaglandins (cyPGs) inhibit human immunodeficiency virus type 1 (HIV-1) replication in various cell types. This antiviral activity has been associated with the induction of heat-shock protein 70 (HSP70) in infected cells. We investigated a new role of prostaglandin A₁ (PGA₁) in the replication of HIV-1 in non-permissive cells. Because overexpression of HSP70 blocks the viral infectivity factor (Vif)-mediated degradation of APOBEC3G (A3G) via the ubiquitin-proteasome pathway, we examined the effects of PGA₁ on A3G and HIV-1 replication. The induction of HSP70 synthesis by PGA₁ blocked Vif-mediated A3G degradation and enhanced the incorporation of A3G into both wild-type and Vif-deficient viruses. Furthermore, we determined the viral titer of HIV-1 particles produced from PGA₁-treated 293T cells. The induction of HSP70 synthesis by PGA₁ significantly reduced the viral titer in the presence of A3G. Additionally, the p24 Gag antigen levels were dramatically reduced in non-permissive cells treated once or repeatedly with PGA₁. Thus, we showed that PGA₁ inhibits HIV-1 replication, at least in part, by blocking Vif-mediated A3G degradation.

  11. Histamine and prostaglandin interaction in regulation of oxytocin and vasopressin secretion.

    Science.gov (United States)

    Knigge, U; Kjaer, A; Kristoffersen, U; Madsen, K; Toftegaard, C; Jørgensen, H; Warberg, J

    2003-10-01

    Prostaglandins and histamine in the hypothalamus are involved in the regulation of oxytocin and vasopressin secretion, and appear to be involved in the mediation of pituitary hormone responses to immunochallenges. Therefore, we investigated in conscious male rats: (i) whether blockade of H1 or H2 receptors affected the oxytocin and vasopressin responses to prostaglandins and (ii) whether blockade of prostaglandin synthesis affected the oxytocin and vasopressin responses to histamine or to Escherichia coli lipopolysaccharide (LPS), in order to determine any interaction between prostaglandins and histamine in the hypothalamus. Oxytocin secretion was dose-dependently stimulated by intracerebroventricular infusion of 1 or 5 microg of PGE1, PGE2 or PGF2alpha, with PGE2 being the most potent of the compounds used. Prior central infusion of the H1 receptor antagonist mepyramine or the H2 receptor antagonist cimetidine significantly inhibited the oxytocin response to all three prostaglandins by approximately 50%. Vasopressin secretion was increased by PGE1 but not by PGE2 or PGF2alpha. The stimulatory effect of PGE1 was almost annihilated by prior administration of mepyramine or cimetidine. Central infusion of histamine or immunochallenge with LPS administered intraperitoneally increased oxytocin and vasopressin secretion four- and two-fold, respectively. Pretreatment with systemic injection of the prostaglandin synthesis inhibitor indomethacin dose-dependently reduced the oxytocin response and prevented the vasopressin response to histamine or LPS. We conclude that histamine and PGE1, PGE2 or PGF2alpha interact in the regulation of oxytocin secretion, whereas histamine and only PGE1 interact in the regulation of vasopressin secretion. Furthermore, histamine as well as LPS may affect oxytocin and vasopressin neurones via activation of prostaglandins, probably in the hypothalamic supraoptic nucleus.

  12. Estrogen receptor-related receptor alpha mediates up-regulation of aromatase expression by prostaglandin E2 in prostate stromal cells.

    Science.gov (United States)

    Miao, Lin; Shi, Jiandang; Wang, Chun-Yu; Zhu, Yan; Du, Xiaoling; Jiao, Hongli; Mo, Zengnan; Klocker, Helmut; Lee, Chung; Zhang, Ju

    2010-06-01

    Estrogen receptor-related receptor alpha (ERRalpha) is an orphan member of the nuclear receptor superfamily of transcription factors. ERRalpha is highly expressed in the prostate, especially in prostate stromal cells. However, little is known about the regulation and function of ERRalpha, which may contribute to the progression of prostatic diseases. We previously found that prostaglandin E2 (PGE2) up-regulated the expression of aromatase in prostate stromal cells. Here we show that PGE2 also up-regulates the expression of ERRalpha, which, as a transcription factor, further mediates the regulatory effects of PGE2 on the expression of aromatase. ERRalpha expression was up-regulated by PGE2 in prostate stromal cell line WPMY-1, which was mediated mainly through the protein kinase A signaling pathway by PGE2 receptor EP2. Suppression of ERRalpha activity by chlordane (an antagonist of ERRalpha) or small interfering RNA knockdown of ERRalpha blocked the increase of expression and promoter activity of aromatase induced by PGE2. Overexpression of ERRalpha significantly increased aromatase expression and promoter activity, which were further augmented by PGE2. Chromatin immunoprecipitation assay demonstrated that ERRalpha directly bound to the aromatase promoter in vivo, and PGE2 enhanced the recruitment of ERRalpha and promoted transcriptional regulatory effects on aromatase expression in WPMY-1. 17Beta-estradiol concentration in WPMY-1 medium was up-regulated by ERRalpha expression, and that was further increased by PGE2. Our results provided evidence that ERRalpha contributed to local estrogen production by up-regulating aromatase expression in response to PGE2 and provided further insights into the potential role of ERRalpha in estrogen-related prostatic diseases.

  13. A comparison of intraamniotic prostaglandin and extraamniotic prostaglandin gel for midtrimester termination of pregnancy.

    Science.gov (United States)

    Smith, D H; Dalrymple, J C

    1983-02-01

    A comparison between midtrimester abortion induced by the intraamniotic injection of prostaglandin F2 alpha and abortion induced by prostaglandin F2 alpha in Tylose gel administered extraamniotically was made in a group of 40 patients. The induction-abortion interval in the extraamniotic group was 12.1 hours which was significantly shorter (P less than 0.001) than the intraamniotic group (27.6 hours). The placenta was expelled completely more often and there were no cervical lacerations using the extraamniotic method whereas 2 patients required repair of cervical lacerations after intraamniotic prostaglandin. Extraamniotic administration of prostaglandin F2 alpha in Tylose gel is recommended as a safe and more effective method for inducing midtrimester abortion than intraamniotic prostaglandin.

  14. Changes in uterine secretion of prostaglandin F2 alpha in response to oxytocin during the estrous cycle, early pregnancy, and estrogen-induced pseudopregnancy in swine.

    Science.gov (United States)

    Edgerton, L A; Kaminski, M A; Silvia, W J

    1996-09-01

    Thirty-one sows were used in an experiment designed to determine whether the ability of the porcine uterus to release prostaglandin (PG) F2 alpha in response to oxytocin was suppressed in pregnancy and pseudopregnancy. Sows were assigned to one of three treatment groups: nonbred (nonpregnant) controls (n = 8), pseudopregnant (5 mg estradiol benzoate, i.m., daily on Days 11-15 postestrus; n = 8), or bred (bred once daily throughout the estrous period; n = 15). Jugular venous blood samples were collected daily for quantification of progesterone. Pregnancy was determined by uterine examination at slaughter 51-72 days postmating. On the basis of progesterone and embryo recovery, bred sows were classified into three subgroups: confirmed pregnant (n = 4), suspected pregnant based on delayed luteal regression (n = 5), or bred/not pregnant (n = 6). All sows received an injection of oxytocin (30 IU, i.v.) on Days 12, 15, and 18 postestrus. Jugular venous blood samples were collected from 60 min prior to through 120 min after injection of oxytocin for quantification of 13, 14-dihydro-15-keto-PGF2 alpha (PGFM). Magnitude of response above baseline and area under the PGFM response curve (AUC) were calculated for each sow on each day and compared among treatment groups by analysis of variance. Responses in pregnant and suspected-pregnant sows were not different on any day examined; therefore the two groups were combined (n = 9) and considered pregnant for all subsequent analyses. Responses in the nonpregnant and bred/not pregnant sows were pooled and compared to the responses in the pregnant and pseudopregnant sows. Magnitudes of response were similar between these pooled groups on Day 12 (p > 0.5), but were less in pregnant and pseudopregnant sows on Days 15 and 18 (p Days 12, 15, and 18 (p > 0.3 on each day). In contrast, when pregnant and pseudopregnant sows were compared, pseudopregnant sows had a lower magnitude of response that was consistent across all 3 days (p < 0

  15. Alpha-tocopherol inhibits pore formation in the oxidized bilayers

    CERN Document Server

    Boonnoy, Phansiri; Wong-ekkabut, Jirasak

    2016-01-01

    In biological membranes, alpha-tocopherols ({\\alpha}-toc; vitamin E) protect polyunsaturated lipids from free radicals. Although the interactions of {\\alpha}-toc with non-oxidized lipid bilayers have been studied, their on oxidized bilayers remain unknown. In this study, atomistic molecular dynamics (MD) simulations of oxidized lipid bilayers were performed with varying concentrations of {\\alpha}-toc. Bilayers with 1-palmitoyl-2-lauroyl-sn-glycero-3-phosphocholine (PLPC) lipids and its aldehyde derivatives at 1:1 ratio were studied. Our simulations show that oxidized lipids self-assemble into aggregates with a water pore rapidly developing across the lipid bilayer. The free energy of transporting an {\\alpha}-toc molecule in a lipid bilayer suggests that {\\alpha}-tocs can passively adsorb into the bilayer. When {\\alpha}-toc molecules were present at low concentrations in bilayers containing oxidized lipids, the formation of water pores was slowed down. At high {\\alpha}-toc concentra-tions, no pores were observ...

  16. Domain a' of protein disulfide isomerase plays key role in inhibiting alpha-synuclein fibril formation.

    Science.gov (United States)

    Cheng, Han; Wang, Lei; Wang, Chih-chen

    2010-07-01

    alpha-Synuclein (alpha Syn) is the main component of Lewy bodies formed in midbrain dopaminergic neurons which is a pathological characteristic of Parkinson's disease. It has been recently showed to induce endoplasmic reticulum (ER) stress and impair ER functions. However, the mechanism of how ER responds to alpha Syn toxicity is poorly understood. In the present study, we found that protein disulfide isomerase (PDI), a stress protein abundant in ER, effectively inhibits alpha Syn fibril formation in vitro. In PDI molecule with a structure of abb'xa'c, domain a' was found to be essential and sufficient for PDI to inhibit alpha Syn fibril formation. PDI was further found to be more avid for binding with intermediate species formed during alpha Syn fibril formation, and the binding was more intensive in the later lag phase. Our results provide new insight into the role of PDI in protecting ER from the deleterious effects of misfolded protein accumulation in many neurodegenerative diseases.

  17. Synergism between the potato glycoalkaloids alpha-chaconine and alpha-solanine in inhibition of snail feeding.

    Science.gov (United States)

    Smith, D B; Roddick, J G; Jones, J L

    2001-05-01

    Snails (Helix aspersa L.) were fed filter paper treated with the potato glycoalkaloids, alpha-solanine and alpha-chaconine, singly or together. In pure form, both glycoalkaloids deterred feeding, with chaconine being the more active compound. In combination, authentic solanine and chaconine interacted synergistically in their inhibition of feeding. The antifeedant activities of methanolic extracts of tuber peel of the potato varieties Majestic and Sharpe's Express presented via filter paper discs did not differ significantly from those of authentic glycoalkaloid solutions of comparable concentration and ratio. In contrast, feeding inhibition by diluted tuber peel extracts of the variety Homeguard was greater than that elicited by comparable authentic glycoalkaloid solutions suggesting additional inhibitory compound(s) in the peel of this variety. Comparison of data from peel extracts of all three potato varieties and authentic glycoalkaloids indicated that the level of feeding inhibition by the extracts was, at least in part, a consequence of a synergism between solanine and chaconine.

  18. 15-Deoxy-Δ12,14-prostaglandin J2 inhibits macrophage colonization by Salmonella enterica serovar Typhimurium.

    Science.gov (United States)

    Buckner, Michelle M C; Antunes, L Caetano M; Gill, Navkiran; Russell, Shannon L; Shames, Stephanie R; Finlay, B Brett

    2013-01-01

    15-deoxy-Δ(12,14)-prostaglandin J2 (15d-PGJ2) is an anti-inflammatory downstream product of the cyclooxygenase enzymes. It has been implicated to play a protective role in a variety of inflammatory mediated diseases, including rheumatoid arthritis, neural damage, and myocardial infarctions. Here we show that 15d-PGJ2 also plays a role in Salmonella infection. Salmonella enterica Typhimurium is a Gram-negative facultative intracellular pathogen that is able to survive and replicate inside phagocytic immune cells, allowing for bacterial dissemination to systemic sites. Salmonella species cause a wide range of morbidity and mortality due to gastroenteritis and typhoid fever. Previously we have shown that in mouse models of typhoid fever, Salmonella infection causes a major perturbation in the prostaglandin pathway. Specifically, we saw that 15d-PGJ2 production was significantly increased in both liver and feces. In this work we show that 15d-PGJ2 production is also significantly increased in macrophages infected with Salmonella. Furthermore, we show that the addition of 15d-PGJ2 to Salmonella infected RAW264.7, J774, and bone marrow derived macrophages is sufficient to significantly reduce bacterial colonization. We also show evidence that 15d-PGJ2 is reducing bacterial uptake by macrophages. 15d-PGJ2 reduces the inflammatory response of these infected macrophages, as evidenced by a reduction in the production of cytokines and reactive nitrogen species. The inflammatory response of the macrophage is important for full Salmonella virulence, as it can give the bacteria cues for virulence. The reduction in bacterial colonization is independent of the expression of Salmonella virulence genes SPI1 and SPI2, and is independent of the 15d-PGJ2 ligand PPAR-γ. 15d-PGJ2 also causes an increase in ERK1/2 phosphorylation in infected macrophages. In conclusion, we show here that 15d-PGJ2 mediates the outcome of bacterial infection, a previously unidentified role for this

  19. 15-Deoxy-Δ12,14-prostaglandin J2 inhibits macrophage colonization by Salmonella enterica serovar Typhimurium.

    Directory of Open Access Journals (Sweden)

    Michelle M C Buckner

    Full Text Available 15-deoxy-Δ(12,14-prostaglandin J2 (15d-PGJ2 is an anti-inflammatory downstream product of the cyclooxygenase enzymes. It has been implicated to play a protective role in a variety of inflammatory mediated diseases, including rheumatoid arthritis, neural damage, and myocardial infarctions. Here we show that 15d-PGJ2 also plays a role in Salmonella infection. Salmonella enterica Typhimurium is a Gram-negative facultative intracellular pathogen that is able to survive and replicate inside phagocytic immune cells, allowing for bacterial dissemination to systemic sites. Salmonella species cause a wide range of morbidity and mortality due to gastroenteritis and typhoid fever. Previously we have shown that in mouse models of typhoid fever, Salmonella infection causes a major perturbation in the prostaglandin pathway. Specifically, we saw that 15d-PGJ2 production was significantly increased in both liver and feces. In this work we show that 15d-PGJ2 production is also significantly increased in macrophages infected with Salmonella. Furthermore, we show that the addition of 15d-PGJ2 to Salmonella infected RAW264.7, J774, and bone marrow derived macrophages is sufficient to significantly reduce bacterial colonization. We also show evidence that 15d-PGJ2 is reducing bacterial uptake by macrophages. 15d-PGJ2 reduces the inflammatory response of these infected macrophages, as evidenced by a reduction in the production of cytokines and reactive nitrogen species. The inflammatory response of the macrophage is important for full Salmonella virulence, as it can give the bacteria cues for virulence. The reduction in bacterial colonization is independent of the expression of Salmonella virulence genes SPI1 and SPI2, and is independent of the 15d-PGJ2 ligand PPAR-γ. 15d-PGJ2 also causes an increase in ERK1/2 phosphorylation in infected macrophages. In conclusion, we show here that 15d-PGJ2 mediates the outcome of bacterial infection, a previously unidentified

  20. Effects of pentoxifylline,platelet activating factor and prostaglandin F 2-alpha on Giant Panda (Ailuropoda melanoleuca) post-thawed sperm in vitro fertilizing capability

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Is it possible that Giant Panda (Ailuropoda melanoleuca) post-thawed sperm fertilization is improved with pentoxifylline (PF),platelet activated factor (PAF) and prostaglandin F 2-alpha (PGF2α)? In our study Giant Panda post-thawed sperm was incubated in Ham's F-10 medium with different concentration of PF,PAF and PGF2α,under 37℃.The effects of PF,PAF and PGF2α,on Giant Panda post-thawed sperm fertility were evaluated through sperm motility,survival time,sperm membrane integrity,acrosome state and heterospecific egg penetration.The results were that PF,PAF and PGF2α all can affect Giant Panda post-thawed sperm in vitro fertilizing capability.In the experiment:1 mg·Ml-1 PF was most suitable for improving Giant Panda post-thawed sperm in vitro fertilizing capability.In the 1 mg·Ml-1 PF group,sperm survival time was (15.33±4.73) h,the heterospecific egg penetration was 51.44% after incubating for 4 hours,the heterospecific egg penetration was 7.49% after incubating for 6 hours.The results of the 1 mg·Ml-1 PF group were significantly higher than those of the control group (P<0.01).The results were also higher than those of the other treatment groups;Treated Giant Panda post-thawed sperm with 50 ng·Ml-1 PAF had a better effect than 100 ng·Ml-1 PAF,but the sperm fertilizing capability was damaged when incubation time exceeded 2 hours;50 ng·Ml-1PGF2α,had no significant effect on Giant Panda postthawed sperm,but when the PGFzα treated concentration was increased,sperm in vitro fertilizing capability decreased because of the damaged motility and declined acrosomal reaction rate.The conclusions suggest that it is possible to improve post-thawed Giant Panda sperm fertility with 1 mg·Ml-1 PF.

  1. Species differences in circulating prostaglandin metabolites. Relevance for the assay of prostaglandin release.

    Science.gov (United States)

    Granström, E; Kindahl, H

    1982-12-13

    The profiles of circulating metabolites of prostaglandin F2 alpha were investigated in a number of species, viz. rat, rabbit, guinea pig, cattle and sheep. The aim of the study was to identify in each animal major plasma metabolites that outlast the initially formed, short-lived 15-keto-13, 14-dihydroprostaglandin F2 alpha and might thus serve as better parameters for monitoring prostaglandin production in vivo. Tritium-labeled prostaglandin F2 alpha was injected intravenously and frequent blood samples were collected. The metabolic profiles at different stages were visualized using two-dimensional thin-layer chromatography and autoradiography. Identification of circulating products was achieved by comparison with reference compounds using several chromatographic methods, and by gas chromatography-mass spectrometry in cases where larger amounts of the prostaglandin had been administered. In the rabbit a similar study was also done with tritium-labeled prostaglandin E2. Certain species differences were seen in the removal of labeled compounds from the circulation, the elimination being most efficient in the guinea pig. Further differences were seen in the profiles of circulating prostaglandin metabolites. The first appearing major prostaglandin F2 alpha metabolite was always 15-ketodihydroprostaglandin F2 alpha. However, this compound was later replaced in the circulation by a number of more degraded products, the profiles of which were relatively typical for each species. Thus, in cattle, rat and guinea pig, the earliest-formed metabolites, 15-ketodihydroprostaglandin F2 alpha and its tetranor counterpart, 5 alpha, 7 alpha-dihydroxy-11-ketotetranorprostanoic acid, remained comparatively prominent plasma products, whereas highly polar dicarboxylic acids rapidly dominated the metabolite spectrum in the ovine and lapine circulation. These differences were further supported by separate kinetic experiments, using unlabeled prostaglandin F2 alpha and radioimmunological

  2. Phytochelatins inhibit the metal-induced aggregation of alpha-crystallin.

    Science.gov (United States)

    Hori, Yasuhisa; Yoshikawa, Tomoaki; Tsuji, Naoki; Bamba, Takeshi; Aso, Yoshikazu; Kudou, Motonori; Uchida, Yoshiki; Takagi, Masahiro; Harada, Kazuo; Hirata, Kazumasa

    2009-02-01

    Phytochelatins (PCs) are heavy-metal-binding peptides found in some eukaryotes. This study investigates the use of plant-derived PCs for the inhibition of metal-induced protein aggregation. The results of this study show that PCs inhibit zinc-induced alpha-crystallin aggregation, and suggest that PCs might be useful as anti-cataract agents.

  3. Alpha interferon and not gamma interferon inhibits salmonid alphavirus subtype 3 replication in vitro.

    Science.gov (United States)

    Xu, Cheng; Guo, Tz-Chun; Mutoloki, Stephen; Haugland, Øyvind; Marjara, Inderjit S; Evensen, Øystein

    2010-09-01

    Salmonid alphavirus (SAV) is an emerging virus in salmonid aquaculture, with SAV-3 being the only subtype found in Norway. Until now, there has been little focus on the alpha interferon (IFN-alpha)-induced antiviral responses during virus infection in vivo or in vitro in fish. The possible involvement of IFN-gamma in the response to SAV-3 is also not known. In this study, the two IFNs were cloned and expressed as recombinant proteins (recombinant IFN-alpha [rIFN-alpha] and rIFN-gamma) and used for in vitro studies. SAV-3 infection in a permissive salmon cell line (TO cells) results in IFN-alpha and IFN-stimulated gene (ISG) mRNA upregulation. Preinfection treatment (4 to 24 h prior to infection) with salmon rIFN-alpha induces an antiviral state that inhibits the replication of SAV-3 and protects the cells against virus-induced cytopathic effects (CPE). The antiviral state coincides with a strong expression of Mx and ISG15 mRNA and Mx protein expression. When rIFN-alpha is administered at the time of infection and up to 24 h postinfection, virus replication is not inhibited, and cells are not protected against virus-induced CPE. By 40 h postinfection, the alpha subunit of eukaryotic initiation factor 2 (eIF2alpha) is phosphorylated concomitant with the expression of the E2 protein as assessed by Western blotting. Postinfection treatment with rIFN-alpha results in a moderate reduction in E2 expression levels in accordance with a moderate downregulation of cellular protein synthesis, an approximately 65% reduction by 60 h postinfection. rIFN-gamma has only a minor inhibitory effect on SAV-3 replication in vitro. SAV-3 is sensitive to the preinfection antiviral state induced by rIFN-alpha, while postinfection antiviral responses or postinfection treatment with rIFN-alpha is not able to limit viral replication.

  4. Substrate-inhibitor interactions in the kinetics of alpha-amylase inhibition by ragi alpha-amylase/trypsin inhibitor (RATI) and its various N-terminal fragments.

    Science.gov (United States)

    Alam, N; Gourinath, S; Dey, S; Srinivasan, A; Singh, T P

    2001-04-10

    The ragi alpha-amylase/trypsin bifunctional inhibitor (RATI) from Indian finger millet, Ragi (Eleucine coracana Gaertneri), represents a new class of cereal inhibitor family. It exhibits a completely new motif of trypsin inhibitory site and is not found in any known trypsin inhibitor structures. The alpha-amylase inhibitory site resides at the N-terminal region. These two sites are independent of each other and the inhibitor forms a ternary (1:1:1) complex with trypsin and alpha-amylase. The trypsin inhibition follows a simple competitive inhibition obeying the canonical serine protease inhibitor mechanism. However, the alpha-amylase inhibition kinetics is a complex one if larger (> or =7 glucose units) substrate is used. While a complete inhibition of trypsin activity can be achieved, the inhibition of amylase is not complete even at very high molar concentration. We have isolated the N-terminal fragment (10 amino acids long) by CNBr hydrolysis of RATI. This fragment shows a simple competitive inhibition of alpha-amylase activity. We have also synthesized various peptides homologous to the N-terminal sequence of RATI. These peptides also show a normal competitive inhibition of alpha-amylase with varying potencies. It has also been shown that RATI binds to the larger substrates of alpha-amylase. In light of these observations, we have reexamined the binding of proteinaceous inhibitors to alpha-amylase and its implications on the mechanism and kinetics of inhibition.

  5. Inhibition of polyamine biosynthesis in Crithidia fasciculata by D,L-alpha-difluoromethylornithine and D,L-alpha-difluoromethylarginine.

    Science.gov (United States)

    Hunter, K J; Strobos, C A; Fairlamb, A H

    1991-05-01

    Using Crithidia fasciculata as a model organism for Trypanosoma cruzi, we have examined the effects of D,L-alpha-difluoromethylornithine (DFMO) and D,L-alpha-difluoromethylarginine (DFMA) on growth and polyamine synthesis. In a defined, polyamine-free medium growth was markedly inhibited by DFMO (94% at 50 mM; IC50 = 37 mM) and to a lesser extent by DFMA (65% at 50 mM). Addition of putrescine, but not agmatine, reverses inhibition of growth, suggesting that the site of inhibition is ornithine decarboxylase (ODC). Consistent with this conclusion, DFMO or DFMA results in a complete loss of putrescine and significant reductions in intracellular spermidine, glutathionylspermidine and N1,N8-bis(glutathionyl)spermidine (trypanothione). In addition, significant concentrations of DFMO (0.8 mM) were present in DFMA-treated cells. However, in contrast to other organisms, conversion of DFMA to DFMO is probably not catalysed by arginase. Substantial ornithine decarboxylase activity (63.1 pmol min-1 mg-1; ODC) was observed in control cells, sufficient to account for polyamine synthesis during growth. In addition, a trace arginine decarboxylase (ADC) activity (1.19 pmol min-1 mg-1) was found. Evidence is presented showing that the apparent ADC activity is actually due to the concerted action of arginase (1.5 nmol min-1 mg-1) and ODC. Thus DFMA appears to inhibit growth of C. fasciculata via conversion to DFMO and subsequent inhibition of ODC.

  6. Diallyl disulfide inhibits proliferation and transdifferentiation of lung fibroblasts through induction of cyclooxygenase and synthesis of prostaglandin E₂.

    Science.gov (United States)

    Wang, Yanhua; Cao, Rong; Wei, Bo; Chai, Xiaoyu; Sun, Dan; Guan, Y; Liu, Xin-min

    2014-08-01

    Platelet-derived growth factor-BB (PDGF-BB) and transforming growth factor-β1 (TGF-β1) are critically involved in idiopathic pulmonary fibrosis by inducing the proliferation and transdifferentiation of lung fibroblasts. In the present study, we examined the impact of diallyl disulfide (DADS), a garlic-derived compound, on such pathological conditions. DADS showed profound inhibitory effects on the PDGF-BB-induced proliferation of human and mouse lung fibroblasts. DADS also abrogated the TGF-β1-induced expression of α-smooth muscle actin, type I collagen and fibronectin. Following treatment with DADS, the expression of cyclooxygenase-2 (COX-2) and the synthesis of prostaglandin E₂ (PGE₂) were found to be markedly enhanced, which in turn led to elevated cAMP levels in lung fibroblasts. Notably, the effect of DADS was largely abolished in the presence of either COX inhibitor indomethacin or siRNA-targeting COX-2, or in the absence of the PGE₂ receptor EP2, supporting an essential role for the COX-2-PGE₂-cAMP autocrine loop. Furthermore, we demonstrated that the upregulated expression of COX-2 was a result of increased level of histone 3 acetylation at COX-2 locus in DADS-treated cells. Together, these results suggest that DADS, by inducing COX-2 expression, may have therapeutic potential in treating lung fibrosis.

  7. Tumor necrosis factor-alpha inhibits insulin's stimulating effect on glucose uptake and endothelium-dependent vasodilation in humans

    DEFF Research Database (Denmark)

    Rask-Madsen, Christian; Domínguez, Helena; Ihlemann, Nikolaj

    2003-01-01

    -alpha was smaller (PTNF-alpha had no effect on the SNP response without insulin infusion. Thus, TNF-alpha inhibition of the combined response to insulin and ACh was likely mediated through inhibition of NO production. CONCLUSIONS: These results support the concept that TNF-alpha could play a role......BACKGROUND: Inflammatory mechanisms could be involved in the pathogenesis of both insulin resistance and atherosclerosis. Therefore, we aimed at examining whether the proinflammatory cytokine tumor necrosis factor (TNF)-alpha inhibits insulin-stimulated glucose uptake and insulin....../or TNF-alpha were coinfused. During infusion of insulin alone for 20 minutes, forearm glucose uptake increased by 220+/-44%. This increase was completely inhibited during coinfusion of TNF-alpha (started 10 min before insulin) with a more pronounced inhibition of glucose extraction than of blood flow...

  8. Lactoferrin from Camelus dromedarius inhibits nuclear transcription Factor-kappa B activation, cyclooxygenase-2 expression and prostaglandin E2 production in stimulated human chondrocytes

    Directory of Open Access Journals (Sweden)

    Naila Rasheed

    2016-01-01

    Full Text Available Background: Osteoarthritis (OA is a progressive joint disorder, which remains the leading cause of chronic disability in aged people. Nuclear factor-kappa B (NF-κB is a major cellular event in OA and its activation by interleukin-1β (IL-1β plays a critical role in cartilage breakdown in these patients. Objective: In this study, we examined the effect of lactoferrin on NF-κB activation, cyclooxygenase-2 (COX-2 expression and prostaglandin E2 (PGE2 production in stimulated human articular chondrocytes. Materials and Methods: Human chondrocytes were derived from OA articular cartilage and treated with camel lactoferrin and then stimulated with IL-1β. Gene expression was determined by TaqMan assays and protein expression was studied by Western immunoblotting. NF-κB activity and PGE2levels were determined by ELISA based assays. NF-κB activity was also determined by treatment of chondrocytes with NF-κB specific inhibitor Bay 11–7082. Results: Lactoferrin inhibited IL-1β-induced activation and nuclear translocation of NF-κB p65 in human OA chondrocytes. Lactoferrin also inhibited mRNA/protein expression of COX-2 and production of PGE2. Moreover, Bay 11–7082 also inhibited IL-1β-induced expression of COX-2 and production of PGE2. The inhibitory effect of lactoferrin on the IL-1β induced expression of COX-2 or production of PGE2was mediated at least in part via suppression of NF-κB activation. Conclusions: Our data determine camel lactoferrin as a novel inhibitor of IL-1β-induced activation of NF-κB signaling events and production of cartilage-degrading molecule PGE2via inhibition of COX-2 expressions. These results may have important implications for the development of novel therapeutic strategies for the prevention/treatment of OA and other degenerative/inflammatory diseases.

  9. Exercise and IL-6 infusion inhibit endotoxin-induced TNF-alpha production in humans

    DEFF Research Database (Denmark)

    Starkie, Rebecca; Ostrowski, Sisse Rye; Jauffred, Sune

    2003-01-01

    During "nondamaging" exercise, skeletal muscle markedly releases interleukin (IL)-6, and it has been suggested that one biological role of this phenomenon is to inhibit the production of tumor necrosis factor (TNF)- alpha, which is known to cause pathogenesis such as insulin resistance...... exercise and rhIL-6 infusion at physiological concentrations inhibit endotoxin-induced TNF-alpha production in humans. Hence, these data provide the first experimental evidence that physical activity mediates antiinflammatory activity and suggest that the mechanism include IL-6, which is produced...... lipopolysaccharide endotoxin (0.06 ng/kg) i.v. to induce low-grade inflammation. In CON, plasma TNF-alpha increased significantly in response to endotoxin. In contrast, during EX, which resulted in elevated IL-6, and rhIL-6, the endotoxin-induced increase in TNF-alpha was totally attenuated. In conclusion, physical...

  10. Purification and properties of a 3 alpha-hydroxysteroid dehydrogenase of rat liver cytosol and its inhibition by anti-inflammatory drugs.

    Science.gov (United States)

    Penning, T M; Mukharji, I; Barrows, S; Talalay, P

    1984-01-01

    An NAD(P)-dependent 3 alpha-hydroxysteroid dehydrogenase (EC 1.1.1.50) was purified to homogeneity from rat liver cytosol, where it is responsible for most if not all of the capacity for the oxidation of androsterone, 1-acenaphthenol and benzenedihydrodiol (trans-1,2-dihydroxycyclohexa-3,5-diene). The dehydrogenase has many properties (substrate specificity, pI, Mr, amino acid composition) in common with the dihydrodiol dehydrogenase (EC 1.3.1.20) purified from the same source [Vogel, Bentley, Platt & Oesch (1980) J. Biol. Chem. 255, 9621-9625]. Since 3 alpha-hydroxysteroids are by far the most efficient substrates, the enzyme is more appropriately designated a 3 alpha-hydroxysteroid dehydrogenase. It also promotes the NAD(P)H-dependent reductions of quinones (e.g. 9,10-phenanthrenequinone, 1,4-benzoquinone), aromatic aldehydes (4-nitrobenzaldehyde) and aromatic ketones (4-nitroacetophenone). The dehydrogenase is not inhibited by dicoumarol, disulfiram, hexobarbital or pyrazole. The mechanism of the powerful inhibition of this enzyme by both non-steroidal and steroidal anti-inflammatory drugs [Penning & Talalay (1983) Proc. Natl. Acad. Sci. U.S.A. 80, 4504-4508] was examined with several substrates. Most non-steroidal anti-inflammatory drugs are competitive inhibitors (e.g. Ki for indomethacin, 0.20 microM for 9,10-phenanthrenequinone reduction at pH 6.0, and 0.835 microM for androsterone oxidation at pH 7.0), except for salicylates, which act non-competitively (e.g. Ki for aspirin, 650 microM for androsterone oxidation). The inhibitory potency of these agents falls sharply as the pH is increased from 6 to 9. Most anti-inflammatory steroids are likewise competitive inhibitors, except for the most potent (betamethasone and dexamethasone), which act non-competitively. The enzyme is inhibited competitively by arachidonic acid and various prostaglandins. PMID:6435601

  11. Inhibition of the prostaglandin E2 receptor EP2 prevents status epilepticus-induced deficits in the novel object recognition task in rats.

    Science.gov (United States)

    Rojas, Asheebo; Ganesh, Thota; Manji, Zahra; O'neill, Theon; Dingledine, Raymond

    2016-11-01

    Survivors of exposure to an organophosphorus nerve agent may develop a number of complications including long-term cognitive deficits (Miyaki et al., 2005; Nishiwaki et al., 2001). We recently demonstrated that inhibition of the prostaglandin E2 receptor, EP2, attenuates neuroinflammation and neurodegeneration caused by status epilepticus (SE) induced by the soman analog, diisopropylfluorophosphate (DFP), which manifest within hours to days of the initial insult. Here, we tested the hypothesis that DFP exposure leads to a loss of cognitive function in rats that is blocked by early, transient EP2 inhibition. Adult male Sprague-Dawley rats were administered vehicle or the competitive EP2 antagonist, TG6-10-1, (ip) at various times relative to DFP-induced SE. DFP administration resulted in prolonged seizure activity as demonstrated by cortical electroencephalography (EEG). A single intraperitoneal injection of TG6-10-1 or vehicle 1 h prior to DFP did not alter the development of seizures, the latency to SE or the duration of SE. Rats administered six injections of TG6-10-1 starting 90 min after the onset of DFP-induced SE could discriminate between a novel and familiar object 6-12 weeks after SE, unlike vehicle treated rats which showed no preference for the novel object. By contrast, behavioral changes in the light-dark box and open field assays were not affected by TG6-10-1. Delayed mortality after DFP was also unaffected by TG6-10-1. Thus, selective inhibition of the EP2 receptor may prevent SE-induced memory impairment in rats caused by exposure to a high dose of DFP.

  12. A RNA antagonist of hypoxia-inducible factor-1alpha, EZN-2968, inhibits tumor cell growth

    DEFF Research Database (Denmark)

    Greenberger, Lee M; Horak, Ivan D; Filpula, David;

    2008-01-01

    pathways, is associated with poor prognosis in many types of cancer. Therefore, down-regulation of HIF-1alpha protein by RNA antagonists may control cancer growth. EZN-2968 is a RNA antagonist composed of third-generation oligonucleotide, locked nucleic acid, technology that specifically binds and inhibits...... the expression of HIF-1alpha mRNA. In vitro, in human prostate (15PC3, PC3, and DU145) and glioblastoma (U373) cells, EZN-2968 induced a potent, selective, and durable antagonism of HIF-1 mRNA and protein expression (IC(50), 1-5 nmol/L) under normoxic and hypoxic conditions associated with inhibition of tumor...

  13. Effective Control of Postprandial Glucose Level through Inhibition of Intestinal Alpha Glucosidase by Cymbopogon martinii (Roxb.

    Directory of Open Access Journals (Sweden)

    Varsha Ghadyale

    2012-01-01

    Full Text Available Inhibition of intestinal alpha glucosidase plays a major role in preventing rise in postprandial glucose level in diabetics. Cymbopogon martinii (CM (family Poaceae is used in traditional Indian medicine in treatment of diabetes mellitus. The alpha glucosidase inhibitory action of the plant is studied. The active component was separated using hot water extraction of the whole plant powder, differential solvent extraction, and silica gel column chromatography. The 30 : 70 toluene : ethyl acetate fraction showed optimum activity. The silica gel chromatography fraction demonstrated 98, 98, and 68% inhibition for starch, maltose, and sucrose, respectively, at 5 mg/kg body weight of rats. Intestinal absorption studies using noneverted intestinal sacs, as well as in vivo studies in streptozotocin-induced diabetic rats using oral glucose tolerance with maltose and sucrose load, revealed better inhibition of alpha glucosidase as compared to acarbose. Kinetic studies using Lineweaver Burk plot showed mixed to noncompetitive type of inhibition by CM. In vivo studies with maltose load of 2 mg and 3 mg/gm body weight showed a noncompetitive pattern of inhibition at 5 mg/kg body weight of CM as against 60 mg/kg body weight of acarbose. Thus CM is more effective alpha glucosidase inhibitor and at lower concentration than acarbose.

  14. Activation of prostaglandin E2-receptor EP2 and EP4 pathways induces growth inhibition in human gastric carcinoma cell lines.

    Science.gov (United States)

    Okuyama, T; Ishihara, S; Sato, H; Rumi, M A K; Kawashima, K; Miyaoka, Y; Suetsugu, H; Kazumori, H; Cava, C F Ortega; Kadowaki, Y; Fukuda, R; Kinoshita, Y

    2002-08-01

    The effect of prostaglandin E2 (PGE2) on the proliferation of gastric cancer cells is still unclear. PGE2 receptors are divided into four subtypes - EP1, EP2, EP3, and EP4 - which are coupled to three different intracellular signal-transduction systems. Stimulation of EP2 and EP4 is linked with cyclic adenosine 3', 5'-monophosphate (cAMP)-dependent protein kinase A (PKA). In some human gastric cancer cells, PGE2 has been suggested to have an antiproliferative effect by way of increased cAMP production. Expression of EP2 and EP4 in human gastric carcinoma cells, however, has not been examined. We examined the expression of EP2 and EP4 and the antiproliferative effects of specific EP2 and EP4 agonists on four different human gastric cancer cell lines. Our data clarified that all the cell lines investigated in this study expressed EP2 and EP4 and that the specific agonists of these receptors induced growth inhibition with an accompanying increase in cAMP production. In summary, gastric cancer cells have EP2 and EP4 receptors, and their selective activation is linked with the decreased cell proliferation.

  15. NO2 inhalation promotes Alzheimer’s disease-like progression: cyclooxygenase-2-derived prostaglandin E2 modulation and monoacylglycerol lipase inhibition-targeted medication

    Science.gov (United States)

    Yan, Wei; Yun, Yang; Ku, Tingting; Li, Guangke; Sang, Nan

    2016-03-01

    Air pollution has been reported to be associated with increased risks of cognitive impairment and neurodegenerative diseases. Because NO2 is a typical primary air pollutant and an important contributor to secondary aerosols, NO2-induced neuronal functional abnormalities have attracted greater attention, but the available experimental evidence, modulating mechanisms, and targeting medications remain ambiguous. In this study, we exposed C57BL/6J and APP/PS1 mice to dynamic NO2 inhalation and found for the first time that NO2 inhalation caused deterioration of spatial learning and memory, aggravated amyloid β42 (Aβ42) accumulation, and promoted pathological abnormalities and cognitive defects related to Alzheimer’s disease (AD). The microarray and bioinformation data showed that the cyclooxygenase-2 (COX-2)-mediated arachidonic acid (AA) metabolism of prostaglandin E2 (PGE2) played a key role in modulating this aggravation. Furthermore, increasing endocannabinoid 2-arachidonoylglycerol (2-AG) by inhibiting monoacylglycerol lipase (MAGL) prevented PGE2 production, neuroinflammation-associated Aβ42 accumulation, and neurodegeneration, indicating a therapeutic target for relieving cognitive impairment caused by NO2 exposure.

  16. Cell cycle arrest by prostaglandin A1 at the G1/S phase interface with up-regulation of oncogenes in S-49 cyc- cells

    Science.gov (United States)

    Hughes-Fulford, M.

    1994-01-01

    Our previous studies have implied that prostaglandins inhibit cell growth independent of cAMP. Recent reports, however, have suggested that prostaglandin arrest of the cell cycle may be mediated through protein kinase A. In this report, in order to eliminate the role of c-AMP in prostaglandin mediated cell cycle arrest, we use the -49 lymphoma variant (cyc-) cells that lack adenylate cyclase activity. We demonstrate that dimethyl prostaglandin A1 (dmPGA1) inhibits DNA synthesis and cell growth in cyc- cells. DNA synthesis is inhibited 42% by dmPGA1 (50 microM) despite the fact that this cell line lacks cellular components needed for cAMP generation. The ability to decrease DNA synthesis depends upon the specific prostaglandin structure with the most effective form possessing the alpha, beta unsaturated ketone ring. Dimethyl PGA1 is most effective in inhibiting DNA synthesis in cyc- cells, with prostaglandins PGE1 and PGB1 being less potent inhibitors of DNA synthesis. DmPGE2 caused a significant stimulation of DNA synthesis. S-49 cyc- variant cells exposed to (30-50 microns) dmPGA1, arrested in the G1 phase of the cell cycle within 24 h. This growth arrest was reversed when the prostaglandin was removed from the cultured cells; growth resumed within hours showing that this treatment is not toxic. The S-49 cyc- cells were chosen not only for their lack of adenylate cyclase activity, but also because their cell cycle has been extensively studied and time requirements for G1, S, G2, and M phases are known. Within hours after prostaglandin removal the cells resume active DNA synthesis, and cell number doubles within 15 h suggesting rapid entry into S-phase DNA synthesis from the G1 cell cycle block.(ABSTRACT TRUNCATED AT 250 WORDS).

  17. The Anti-inflammatory Prostaglandin 15-Deoxy-Δ12,14-PGJ2 Inhibits CRM1-dependent Nuclear Protein Export*

    OpenAIRE

    Hilliard, Mark; Frohnert, Cornelia; Spillner, Christiane; Marcone, Simone; Nath, Annegret; Lampe, Tina; Fitzgerald, Desmond J; Kehlenbach, Ralph H.

    2010-01-01

    The signaling molecule 15-deoxy-Δ12,14-prostaglandin J2 (15d-PGJ2) has been described as the “anti-inflammatory prostaglandin.” Here we show that substrates of the nuclear export receptor CRM1 accumulate in the nucleus in the presence of 15d-PGJ2, identifying this prostaglandin as a regulator of CRM1-dependent nuclear protein export that can be produced endogenously. Like leptomycin B (LMB), an established fungal CRM1-inhibitor, 15d-PGJ2 reacts with a conserved cysteine residue in the CRM1 se...

  18. Determination of the alpha-tocopherol inhibition rate constant for peroxidation in low-density lipoprotein.

    Science.gov (United States)

    Culbertson, Sean M; Antunes, Fernando; Havrilla, Christine M; Milne, Ginger L; Porter, Ned A

    2002-06-01

    This work reports an estimate of the inhibition rate constant (k(inh)) for alpha-tocopherol (alpha-TOH) in low-density lipoproteins (LDL) based on cholesteryl linoleate hydroperoxide products formed during autoxidation of intact lipoproteins. The ratio of cis,trans/trans,trans product hydroperoxides was determined during the consumption of the antioxidant. For a reasonable determination of k(inh) in LDL, the pro-oxidant behavior of alpha-TOH was minimized by oxidizing LDL with an unsymmetrical amphiphilic azo initiator which significantly reduces phase-transfer mediated pro-oxidant effects of alpha-TOH. This initiator delivers a more constant flux of initiator radicals into LDL lipid regions and permits determination of alpha-TOH k(inh) in LDL. Development of a tocopherol-mediated peroxidation (TMP) model and analysis of cholesteryl linoleate hydroperoxide cis,trans/trans,trans product ratios provided an estimated value for the inhibition rate constant of alpha-TOH in a lipoprotein of k(inh) = 5.9 +/- 0.5 x 10(5) M(-)(1) s(-)(1)

  19. 15-Deoxy-Δ{sup 12,14}-prostaglandin J{sub 2} inhibits IL-13 production in T cells via an NF-κB-dependent mechanism

    Energy Technology Data Exchange (ETDEWEB)

    Doyle, Marie-Christine; Tremblay, Sarah [Département de Biologie, Faculté des Sciences, Université de Sherbrooke, Sherbrooke (QC), Canada J1K 2R1 (Canada); Dumais, Nancy, E-mail: nancy.dumais@usherbrooke.ca [Département de Biologie, Faculté des Sciences, Université de Sherbrooke, Sherbrooke (QC), Canada J1K 2R1 (Canada)

    2013-02-15

    Highlights: ► 15d-PGJ{sub 2} decreased IL-13 mRNA transcription and secretion in activated T cells. ► IL-13 inhibition by 15d-PGJ{sub 2} is independent of PPAR-γ. ► The nuclear factor-κB mediates the 15d-PGJ{sub 2}-dependent down regulation of IL-13. -- Abstract: Interleukin (IL)-13 is a cytokine produced by activated CD4{sup +} T cells that plays a critical role in promoting allergic responses and tumor cell growth. The 15-deoxy-Δ{sup 12,14}-prostaglandin J{sub 2} (15d-PGJ{sub 2}) is a natural ligand for the nuclear receptor peroxisome proliferator-activated receptor gamma (PPAR-γ), a known regulator of anti-inflammatory activities. We determined the effects of 15d-PGJ{sub 2} on IL-13 expression in the Jurkat E6.1 T-cell line and in peripheral blood mononuclear cells. Semi-quantitative reverse transcription-polymerase chain reaction and enzyme-linked immunosorbent assay revealed that treatment of activated T cells with 15d-PGJ{sub 2} significantly decreased IL-13 mRNA transcription and secretion, respectively. This inhibition by 15d-PGJ{sub 2} was independent of PPAR-γ since treatment with GW9662, an irreversible antagonist of the nuclear receptor, produced no effect. Our data also revealed the involvement of nuclear factor-κB in mediating 15d-PGJ{sub 2}-dependent down regulation of IL-13 expression. Collectively, these results demonstrate the potential of 15d-PGJ{sub 2} in attenuating expression and production of IL-13 in activated T cells.

  20. Tumor necrosis factor-alpha inhibits myogenesis through redox-dependent and -independent pathways

    NARCIS (Netherlands)

    Langen, R.C.J.; Schols, A.M.W.J.; Kelders, M.C.J.M.; van der Velden, A.L.J.; Wouters, E.F.M.; Janssen, Y.M.W.

    2002-01-01

    Tumor necrosis factor-alpha inhibits myogenesis through redox-dependent and -independent pathways. Langen RC, Schols AM, Kelders MC, Van Der Velden JL, Wouters EF, Janssen-Heininger YM. Department of Pulmonology, Maastricht University, The Netherlands. Muscle wasting accompanies diseases that are as

  1. Inhibition of neointima formation by local delivery of estrogen receptor alpha and beta specific agonists

    NARCIS (Netherlands)

    Krom, Y.D.; Pires, N.M.M.; Jukema, J.W.; Vries, M.R. de; Frants, R.R.; Havekes, L.M.; Dijk, K.W. van; Quax, P.H.A.

    2007-01-01

    Objective: Neointima formation is the underlying mechanism of (in-stent) restenosis. 17β-Estradiol (E2) is known to inhibit injury-induced neointima formation and post-angioplasty restenosis. Estrogen receptor alpha (ERα) has been demonstrated to mediate E2 anti-restenotic properties. However, the r

  2. Miconia sp. Increases mRNA Levels of PPAR Gamma and Inhibits Alpha Amylase and Alpha Glucosidase

    Science.gov (United States)

    Ortíz-Martinez, David Mizael; Rivas-Morales, Catalina; de la Garza-Ramos, Myriam Angelica; Verde-Star, Maria Julia; Nuñez-Gonzalez, Maria Adriana

    2016-01-01

    Diabetes mellitus is a public health problem worldwide. For this reason, ethanolic extract of Miconia sp. from Oaxaca, Mexico, was selected in search of an alternative against this disease. The effect of Miconia sp. on mRNA expression of PPARγ on cell line 3T3-L1, its effect on alpha amylase and alpha glucosidase, lipid accumulation during adipogenesis, and cell viability on VERO cells were evaluated. The mRNA levels of PPARγ increased on 1.393 ± 0.008 folds, lipid accumulation was increased by 29.55% with Miconia sp. extract and 34.57% with rosiglitazone, and α-amylase and α-glycosidase were inhibited with IC50 values from 28.23 ± 2.15 μg/mL and 1.95 ± 0.15 μg/mL, respectively; the IC50 on antiproliferative activity on VERO cells was 314.54 ± 45.40 μg/mL. In case of α-amylase and α-glycosidase assays, IC50 (inhibitory concentration 50) refers to necessary extract amounts to inhibit 50% of enzymatic activity. On the other hand, on antiproliferative activity, IC50 (inhibitory concentration 50) refers to necessary extract amounts to inhibit 50% of cell proliferation. It was concluded that the compounds present in Miconia sp. ethanolic extract increase mRNA expression of PPARγ, inhibit α-amylase and α-glucosidase, and increase lipid accumulation. It constitutes an alternative as adjuvant in diabetes mellitus treatment; therefore, we recommend continuing identifying the compounds responsible for its promising in vivo antidiabetic activity. PMID:27478477

  3. Miconia sp. Increases mRNA Levels of PPAR Gamma and Inhibits Alpha Amylase and Alpha Glucosidase.

    Science.gov (United States)

    Ortíz-Martinez, David Mizael; Rivas-Morales, Catalina; de la Garza-Ramos, Myriam Angelica; Verde-Star, Maria Julia; Nuñez-Gonzalez, Maria Adriana; Leos-Rivas, Catalina

    2016-01-01

    Diabetes mellitus is a public health problem worldwide. For this reason, ethanolic extract of Miconia sp. from Oaxaca, Mexico, was selected in search of an alternative against this disease. The effect of Miconia sp. on mRNA expression of PPARγ on cell line 3T3-L1, its effect on alpha amylase and alpha glucosidase, lipid accumulation during adipogenesis, and cell viability on VERO cells were evaluated. The mRNA levels of PPARγ increased on 1.393 ± 0.008 folds, lipid accumulation was increased by 29.55% with Miconia sp. extract and 34.57% with rosiglitazone, and α-amylase and α-glycosidase were inhibited with IC50 values from 28.23 ± 2.15 μg/mL and 1.95 ± 0.15 μg/mL, respectively; the IC50 on antiproliferative activity on VERO cells was 314.54 ± 45.40 μg/mL. In case of α-amylase and α-glycosidase assays, IC50 (inhibitory concentration 50) refers to necessary extract amounts to inhibit 50% of enzymatic activity. On the other hand, on antiproliferative activity, IC50 (inhibitory concentration 50) refers to necessary extract amounts to inhibit 50% of cell proliferation. It was concluded that the compounds present in Miconia sp. ethanolic extract increase mRNA expression of PPARγ, inhibit α-amylase and α-glucosidase, and increase lipid accumulation. It constitutes an alternative as adjuvant in diabetes mellitus treatment; therefore, we recommend continuing identifying the compounds responsible for its promising in vivo antidiabetic activity.

  4. Miconia sp. Increases mRNA Levels of PPAR Gamma and Inhibits Alpha Amylase and Alpha Glucosidase

    Directory of Open Access Journals (Sweden)

    David Mizael Ortíz-Martinez

    2016-01-01

    Full Text Available Diabetes mellitus is a public health problem worldwide. For this reason, ethanolic extract of Miconia sp. from Oaxaca, Mexico, was selected in search of an alternative against this disease. The effect of Miconia sp. on mRNA expression of PPARγ on cell line 3T3-L1, its effect on alpha amylase and alpha glucosidase, lipid accumulation during adipogenesis, and cell viability on VERO cells were evaluated. The mRNA levels of PPARγ increased on 1.393±0.008 folds, lipid accumulation was increased by 29.55% with Miconia sp. extract and 34.57% with rosiglitazone, and α-amylase and α-glycosidase were inhibited with IC50 values from 28.23±2.15 μg/mL and 1.95±0.15 μg/mL, respectively; the IC50 on antiproliferative activity on VERO cells was 314.54±45.40 μg/mL. In case of α-amylase and α-glycosidase assays, IC50 (inhibitory concentration 50 refers to necessary extract amounts to inhibit 50% of enzymatic activity. On the other hand, on antiproliferative activity, IC50 (inhibitory concentration 50 refers to necessary extract amounts to inhibit 50% of cell proliferation. It was concluded that the compounds present in Miconia sp. ethanolic extract increase mRNA expression of PPARγ, inhibit α-amylase and α-glucosidase, and increase lipid accumulation. It constitutes an alternative as adjuvant in diabetes mellitus treatment; therefore, we recommend continuing identifying the compounds responsible for its promising in vivo antidiabetic activity.

  5. Melatonin inhibits both ER alpha activation and breast cancer cell proliferation induced by a metalloestrogen, cadmium.

    Science.gov (United States)

    Martínez-Campa, C; Alonso-González, C; Mediavilla, M D; Cos, S; González, A; Ramos, S; Sánchez-Barceló, E J

    2006-05-01

    Cadmium (Cd) is a heavy metal affecting human health both through environmental and occupational exposure. There is evidence that Cd accumulates in several organs and is carcinogenic to humans. In vivo, Cd mimics the effect of estrogens in the uterus and mammary gland. In estrogen-responsive breast cancer cell lines, Cd stimulates proliferation and can also activate the estrogen receptor independent of estradiol. The ability of this metalloestrogen to increase gene expression in MCF7 cells is blocked by anti-estrogens suggesting that the activity of these compounds is mediated by ER alpha. The aims of this work were to test whether melatonin inhibits Cd-induced proliferation in MCF7 cells, and also to study whether melatonin specifically inhibits Cd-induced ER alpha transactivation. We show that melatonin prevents the Cd-induced growth of synchronized MCF7 breast cancer cells. In transient transfection experiments, we prove that both ER alpha- and ER beta-mediated transcription are stimulated by Cd. Melatonin is a specific inhibitor of Cd-induced ER alpha-mediated transcription in both estrogen response elements (ERE)- and AP1-containing promoters, whereas ER beta-mediated transcription is not inhibited by the pineal indole. Moreover, the mutant ER alpha-(K302G, K303G), unable to bind calmodulin, is activated by Cd but becomes insensitive to melatonin treatment. These results proved that melatonin inhibits MCF7 cell growth induced by Cd and abolishes the stimulatory effect of the heavy metal in cells expressing ER alpha at both ERE-luc and AP1-luc sites. We can infer from these experiments that melatonin regulates Cd-induced transcription in both ERE- and AP1 pathways. These results also reinforce the hypothesis of the anti-estrogenic properties of melatonin as a valuable tool in breast cancer therapies.

  6. Sulfate- and sialic acid-containing glycolipids inhibit DNA polymerase alpha activity.

    Science.gov (United States)

    Simbulan, C M; Taki, T; Tamiya-Koizumi, K; Suzuki, M; Savoysky, E; Shoji, M; Yoshida, S

    1994-03-16

    The effects of various glycolipids on the activity of immunoaffinity-purified calf thymus DNA polymerase alpha were studied in vitro. Preincubation with sialic acid-containing glycolipids, such as sialosylparagloboside (SPG), GM3, GM1, and GD1a, and sulfatide (cerebroside sulfate ester, CSE) dose-dependently inhibited the activity of DNA polymerase alpha, while other glycolipids, as well as free sphingosine and ceramide did not. About 50% inhibition was achieved by preincubating the enzyme with 2.5 microM of CSE, 50 microM of SPG or GM3, and 80 microM of GM1. Inhibition was noncompetitive with both the DNA template and the substrate dTTP, as well as with the other dNTPs. Since the inhibition was largely reversed by the addition of 0.05% Nonidet P40, these glycolipids may interact with the hydrophobic region of the enzyme protein. Apparently, the sulfate moiety in CSE and the sialic acid moiety in gangliosides were essential for the inhibition since neither neutral glycolipids (i.e., glucosylceramide, galactosylceramide, lactosylceramide) nor asialo-gangliosides (GA1 and GA2) showed any inhibitory effect. Furthermore, the ceramide backbone was also found to be necessary for maximal inhibition since the inhibition was largely abolished by substituting the lipid backbone with cholesterol. Increasing the number of sialic acid moieties per molecule further enhanced the inhibition, while elongating the sugar chain diminished it. It was clearly shown that the N-acetyl residue of the sialic acid moiety is particularly essential for inhibition by both SPG and GM3 because the loss of this residue or substitution with a glycolyl residue completely negated their inhibitory effect on DNA polymerase alpha activity.

  7. Screening and identification of dietary oils and unsaturated fatty acids in inhibiting inflammatory prostaglandin E2 signaling in fat stromal cells

    Directory of Open Access Journals (Sweden)

    Ruan Diana

    2012-08-01

    Full Text Available Abstract Background The molecular mechanisms of dietary oils (such as fish oil and unsaturated fatty acids, which are widely used by the public for anti-inflammation and vascular protection, have not been settled yet. In this study, prostaglandin E2 (PGE2-mediated calcium signaling was used to screen dietary oils and eight unsaturated fatty acids for identification of their anti-inflammatory mechanisms. Isolated fat/stromal cells expressing endogenous PGE2 receptors and an HEK293 cell line specifically expressing the recombinant human PGE2 receptor subtype-1 (EP1 were cultured and used in live cell calcium signaling assays. The different dietary oils and unsaturated fatty acids were used to affect cell signaling under the specific stimulation of a pathological amount of inflammatory PGE2. Results It was identified that fish oil best inhibited the PGE2 signaling in the primary cultured stromal cells. Second, docosahexaenoic acid (DHA, found in abundance in fish oil, was identified as a key factor of inhibition of PGE2 signaling. Eicosapentaenoic acid (EPA, another major fatty acid found in fish oil and tested in this study was found to have small effect on EP1 signaling. The study suggested one of the four PGE2 subtype receptors, EP1 as the key target for the fish oil and DHA target. These findings were further confirmed by using the recombinant EP1 expressed in HEK293 cells as a target. Conclusion This study demonstrated the new mechanism behind the positive effects of dietary fish oils in inhibiting inflammation originates from the rich concentration of DHA, which can directly inhibit the inflammatory EP1-mediated PGE2 receptor signaling, and that the inflammatory response stimulated by PGE2 in the fat stromal cells, which directly related to metabolic diseases, could be down regulated by fish oil and DHA. These findings also provided direct evidence to support the use of dietary oils and unsaturated fatty acids for protection against heart

  8. Omentin inhibits TNF-{alpha}-induced expression of adhesion molecules in endothelial cells via ERK/NF-{kappa}B pathway

    Energy Technology Data Exchange (ETDEWEB)

    Zhong, Xia, E-mail: zhongxia1977@126.com [Department of Emergency, Provincial Hospital Affiliated to Shandong University, Jinan 250021 (China); Li, Xiaonan; Liu, Fuli; Tan, Hui [Department of Emergency, Provincial Hospital Affiliated to Shandong University, Jinan 250021 (China); Shang, Deya, E-mail: wenhuashenghuo1@163.com [Department of Emergency, Provincial Hospital Affiliated to Shandong University, Jinan 250021 (China)

    2012-08-24

    Highlights: Black-Right-Pointing-Pointer Omentin inhibited TNF-{alpha}-induced adhesion of THP-1 cells to HUVECs. Black-Right-Pointing-Pointer Omentin reduces expression of ICAM-1 and VCAM-1 induced by TNF-{alpha} in HUVECs. Black-Right-Pointing-Pointer Omentin inhibits TNF-{alpha}-induced ERK and NF-{kappa}B activation in HUVECs. Black-Right-Pointing-Pointer Omentin supreeses TNF-{alpha}-induced expression of ICAM-1 and VCAM-1 via ERK/NF-{kappa}B pathway. -- Abstract: In the present study, we investigated whether omentin affected the expression of intracellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) in tumor necrosis factor-{alpha} (TNF-{alpha}) induced human umbilical vein endothelial cells (HUVECs). Our data showed that omentin decreased TNF-{alpha}-induced expression of ICAM-1 and VCAM-1 in HUVECs. In addition, omentin inhibited TNF-{alpha}-induced adhesion of THP-1 cells to HUVECs. Further, we found that omentin inhibited TNF-{alpha}-activated signal pathway of nuclear factor-{kappa}B (NF-{kappa}B) by preventing NF-{kappa}B inhibitory protein (I{kappa}B{alpha}) degradation and NF-{kappa}B/DNA binding activity. Omentin pretreatment significantly inhibited TNF-{alpha}-induced ERK activity and ERK phosphorylation in HUVECs. Pretreatment with PD98059 suppressed TNF-{alpha}-induced NF-{kappa}B activity. Omentin, NF-kB inhibitor (BAY11-7082) and ERK inhibitor (PD98059) reduced the up-regulation of ICAM-1 and VCAM-1 induced by TNF-{alpha}. These results suggest that omentin may inhibit TNF-{alpha}-induced expression of adhesion molecules in endothelial cells via blocking ERK/NF-{kappa}B pathway.

  9. Simultaneous use of two prostaglandin radioimmunoassays employing two antisera of differing specificity. II. Relative stability of prostaglandins E1, E2, and F1alpha in cell cultures of BALB/c 3T3 and SV3T3 mouse fibroblasts

    Energy Technology Data Exchange (ETDEWEB)

    Ritzi, E.M.; Stylos, W.A.

    1976-11-01

    The relative stability of Prostaglandins (PGs) E1, E2 and F1..cap alpha.. in cultures of BALB/c 3T3 and SV3T3 cells has been evaluated using 3 different approaches. First, total recovery of tritium in the ethyl acetate phase following incubation and extraction of PGF1..cap alpha.. and PGE1 demonstrated greater stability for PGF1..cap alpha.. (88.8 percent) than PGE1 (65.9 percent). Second, analysis of incubated, extracted, tritiated PGs by thin layer chromatography revealed decreases of up to 23 percent in the PGE zone following incubation of 3H-PGE1. With increasing time of incubation, decreases in the PGE zone were accompanied by increase in PGA-like compounds. 3H-PGF1..cap alpha.. demonstrated greater stability, having greater than 90 percent recovery of the tritium in the PGF zone. A third approach to the assessment of PG stability in culture was the comparison of the production of individual PGs by radioimmunoassay (RIA). The data obtained by RIA indicated a lag in the increase of PGA and PGB, until an initial rise in PGE was noted, suggesting that PGA and PGB may be secondary products arising from PGE which exhibits only partial stability in culture. By employing two RIAs, one for total PGE and one for PGA and PGB, the composite determination PG (E + (A + B)) can be used to provide a more meaningful determination of PG production because of the instability of the PGs. On the other hand, individual determinations are helpful in assessing the stability of PGEs in cell cultures.

  10. Inhibition of mitochondrial division through covalent modification of Drp1 protein by 15 deoxy-{Delta}{sup 12,14}-prostaglandin J2

    Energy Technology Data Exchange (ETDEWEB)

    Mishra, Nandita [Department of Pathology, UT Health Science Center at San Antonio, San Antonio, TX 78229 (United States); Kar, Rekha [Department of Biochemistry, UT Health Science Center at San Antonio, San Antonio, TX 78229 (United States); Singha, Prajjal K. [Department of Pathology, UT Health Science Center at San Antonio, San Antonio, TX 78229 (United States); Venkatachalam, Manjeri A. [Department of Pathology, UT Health Science Center at San Antonio, San Antonio, TX 78229 (United States); Department of Biochemistry, UT Health Science Center at San Antonio, San Antonio, TX 78229 (United States); McEwen, Donald G. [Greehey Children' s Cancer Research Institute, UT Health Science Center at San Antonio, San Antonio, TX 78229 (United States); Saikumar, Pothana, E-mail: saikumar@uthscsa.edu [Department of Pathology, UT Health Science Center at San Antonio, San Antonio, TX 78229 (United States)

    2010-04-23

    Arachidonic acid derived endogenous electrophile 15d-PGJ2 has gained much attention in recent years due to its potent anti-proliferative and anti-inflammatory actions mediated through thiol modification of cysteine residues in its target proteins. Here, we show that 15d-PGJ2 at 1 {mu}M concentration converts normal mitochondria into large elongated and interconnected mitochondria through direct binding to mitochondrial fission protein Drp1 and partial inhibition of its GTPase activity. Mitochondrial elongation induced by 15d-PGJ2 is accompanied by increased assembly of Drp1 into large oligomeric complexes through plausible intermolecular interactions. The role of decreased GTPase activity of Drp1 in the formation of large oligomeric complexes is evident when Drp1 is incubated with a non-cleavable GTP analog, GTP{gamma}S or by a mutation that inactivated GTPase activity of Drp1 (K38A). The mutation of cysteine residue (Cys644) in the GTPase effector domain, a reported target for modification by reactive electrophiles, to alanine mimicked K38A mutation induced Drp1 oligomerization and mitochondrial elongation, suggesting the importance of cysteine in GED to regulate the GTPase activity and mitochondrial morphology. Interestingly, treatment of K38A and C644A mutants with 15d-PGJ2 resulted in super oligomerization of both mutant Drp1s indicating that 15d-PGJ2 may further stabilize Drp1 oligomers formed by loss of GTPase activity through covalent modification of middle domain cysteine residues. The present study documents for the first time the regulation of a mitochondrial fission activity by a prostaglandin, which will provide clues for understanding the pathological and physiological consequences of accumulation of reactive electrophiles during oxidative stress, inflammation and degeneration.

  11. Alpha-fluoromethylhistidine, a histamine synthesis inhibitor, inhibits orexin-induced wakefulness in rats.

    Science.gov (United States)

    Yasuko, Seki; Atanda, Akanmu Moses; Masato, Matsuura; Kazuhiko, Yanai; Kazuki, Honda

    2010-02-11

    Orexins A and B are involved in the regulation of feeding and arousal state. Previously, we reported that third intracerebroventricular (icv) infusion of both orexins A and B induced a significant arousal effect in rats. We determined the effects of intraperitoneal (i.p.) injection of alpha-fluoromethylhistidine (alpha-FMH), a histamine synthesis inhibitor, on orexin-induced wakefulness in freely behaving rats. Male Sprague-Dawley rats were chronically implanted with cortical electroencephalogram (EEG) and neck electromyogram (EMG) electrodes, and a cannula for icv infusion. EEG and EMG were monitored for three consecutive days during continuous icv saline infusion at a rate of 10 microl/h. For a 5-h diurnal period, orexin-B (10 nmol/50 microl saline) replaced the icv infusion of saline. alpha-FMH (100mg/kg, i.p.) was administered 6h before icv infusion of orexin-B. Orexin-B at a dose of 10 nmol/h markedly increased the amount of wakefulness by 99.4% (p<0.05) over the baseline value, whereas alpha-FMH decreased orexin-B-induced wakefulness by 48.8%. Orexin-B-induced suppression of non-REM sleep was reversed by alpha-FMH treatment. Pretreatment with alpha-FMH, significantly inhibited orexin-B-induced wakefulness in rats. The findings of this study therefore suggest that arousal-state regulation by orexin neurons is possibly mediated via the histaminergic system in the tuberomammilary nucleus.

  12. Prostaglandins and prostaglandin receptor antagonism in migraine

    DEFF Research Database (Denmark)

    Antonova, Maria

    2013-01-01

    Human models of headache may contribute to understanding of prostaglandins' role in migraine pathogenesis. The current thesis investigated the migraine triggering effect of prostaglandin E2 (PGE2) in migraine patients without aura, the efficacy of a novel EP4 receptor antagonist, BGC20......-1531, in prevention of PGE2-induced headache and the ability of prostaglandin F2α (PGF2α) to trigger headache without any vasodilatation in healthy volunteers. All studies were designed as double-blind, placebo-controlled, cross-over experiments, where PGE2/PGF2α or saline were infused over 20-25 min. In the study...

  13. Inhibition of tumour necrosis factor-alpha (TNF-alpha) release from mast cells by the anti-inflammatory drugs, sodium cromoglycate and nedocromil sodium.

    Science.gov (United States)

    Bissonnette, E Y; Enciso, J A; Befus, A D

    1995-01-01

    TNF-alpha is a cytokine thought to be involved in the pathogenesis of asthma and in several other inflammatory conditions. Given recent evidence that mast cells (MC) are an important source of TNF-alpha, we investigated the effects of two anti-inflammatory drugs, nedocromil sodium (NED) and sodium cromoglycate (SCG), on rat MC-derived TNF-alpha. We established that at least 2 h pretreatment with NED or SCG followed by washing was required to inhibit TNF-alpha-dependent cytotoxicity by rat peritoneal MC (PMC). A maximum inhibition of TNF-alpha occurred after 6 h treatment. The inhibitory effect of NED and SCG (10(-5)-10(-3)M) was concentration-dependent (20-37% for NED and 16-37% for SCG). The time-course analysis and the use of cycloheximide, an inhibitor of protein synthesis, provided strong evidence that new protein synthesis by the MC is required for this inhibitory effect. Furthermore, 24 h treatment with 1 mM NED inhibited the levels of mRNA for TNF-alpha by 59-83%. In addition to the effect on TNF-alpha-dependent cytotoxicity by MC, 20 min pretreatment with 10(-4) M NED and SCG inhibited antigen-stimulated TNF-alpha release (6h) by 42% and 48%, respectively. Interestingly, the functionally distinct intestinal mucosal MC (IMMC) is unresponsive to these drugs with regard to histamine secretion. However, as with PMC, 2h pretreatment with NED or SCG inhibited TNF-alpha-dependent cytotoxicity by IMMC. These effects may be important in the action of these drugs in vivo in the late phase reaction in asthma or other inflammatory conditions. Images Fig. 6 PMID:7554404

  14. 15-deoxy-δ12,14-prostaglandin j2 inhibits osteolytic breast cancer bone metastasis and estrogen deficiency-induced bone loss.

    Directory of Open Access Journals (Sweden)

    Ki Rim Kim

    Full Text Available Breast cancer is the major cause of cancer death in women worldwide. The most common site of metastasis is bone. Bone metastases obstruct the normal bone remodeling process and aberrantly enhance osteoclast-mediated bone resorption, which results in osteolytic lesions. 15-deoxy-Δ12,14-prostaglandin J2 (15d-PGJ2 is an endogenous ligand of peroxisome proliferator-activated receptor gamma (PPARγ that has anti-inflammatory and antitumor activity at micromolar concentrations through PPARγ-dependent and/or PPARγ-independent pathways. We investigated the inhibitory activity of 15d-PGJ2 on the bone loss that is associated with breast cancer bone metastasis and estrogen deficiency caused by cancer treatment. 15d-PGJ2 dose-dependently inhibited viability, migration, invasion, and parathyroid hormone-related protein (PTHrP production in MDA-MB-231 breast cancer cells. 15d-PGJ2 suppressed receptor activator of nuclear factor kappa-B ligand (RANKL mRNA levels and normalized osteoprotegerin (OPG mRNA levels in hFOB1.19 osteoblastic cells treated with culture medium from MDA-MB-231 cells or PTHrP, which decreased the RANKL/OPG ratio. 15d-PGJ2 blocked RANKL-induced osteoclastogenesis and inhibited the formation of resorption pits by decreasing the activities of cathepsin K and matrix metalloproteinases, which are secreted by mature osteoclasts. 15d-PGJ2 exerted its effects on breast cancer and bone cells via PPARγ-independent pathways. In Balb/c nu/nu mice that received an intracardiac injection of MDA-MB-231 cells, subcutaneously injected 15d-PGJ2 substantially decreased metastatic progression, cancer cell-mediated bone destruction in femora, tibiae, and mandibles, and serum PTHrP levels. 15d-PGJ2 prevented the destruction of femoral trabecular structures in estrogen-deprived ICR mice as measured by bone morphometric parameters and serum biochemical data. Therefore, 15d-PGJ2 may be beneficial for the prevention and treatment of breast cancer

  15. Cocaine synergism with alpha agonists in rat aorta: computational analysis reveals an action beyond reuptake inhibition*

    Science.gov (United States)

    Lamarre, Neil S.; Raffa, Robert B.; Tallarida, Ronald J.

    2012-01-01

    BACKGROUND Cocaine has long been known to increase blood pressure, but the degree and mechanism of vasoconstricting action remain poorly understood. Here we examine the interaction between cocaine and alpha-adrenoceptor agonists, with the action of reuptake inhibition minimized. METHODS Cocaine was administered to isolated rings of rat thoracic aorta, alone and in combination with three different adrenoceptor agonists: phenylephrine, methoxamine, and norepinephrine. Synergy analysis begins with the predicted additive effect of the combination of two agonists, based upon dose equivalence theory. This case where one agonist (cocaine) has no effect when administered alone requires only a t-test to demonstrate that a departure from additivity has occurred. RESULTS At doses where cocaine alone produced no vasoconstriction, it potentiated the vasoconstriction produced by all three alpha agonists, a clear indication of synergism between cocaine and these agents. Higher doses of cocaine in combination with alpha adrenoceptor agents gave an inverted-U shaped (hormetic) dose-effect curve, i.e., dose-related relaxation at higher doses. The hormetic dose-effect relation was analyzed using computational methodology based on dose equivalence to derive the unknown second component of action that causes relaxation. CONCLUSIONS Cocaine exhibits both vasoconstricting and vasorelaxant effects. This relaxing component, possibly related to activation of myosin light chain phosphatase, was quantified as a dose-effect curve. Most important is the synergism between cocaine and alpha-adrenoceptor stimulation which cannot be explained as an action due to reuptake inhibition, and has not been previously described. PMID:23270987

  16. Inhibition of mucin glycosylation by aryl-N-acetyl-alpha-galactosaminides in human colon cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Kuan, S.F.; Byrd, J.C.; Basbaum, C.; Kim, Y.S. (Veterans Administration Medical Center, San Francisco, CA (USA))

    1989-11-15

    Specific inhibitors of the glycosylation of O-glycosidically linked glycoproteins have not previously been described. When tested for their effects on mucin glycosylation in a mucin-producing colon cancer cell line, LS174T, benzyl-, phenyl-, and p-nitrophenyl-N-acetyl-alpha-galactosaminide inhibited the formation of fully glycosylated mucin in a dose-dependent manner. Free aryl-oligosaccharides were found in the medium of treated cells labeled with ({sup 3}H)glucosamine, ({sup 3}H)galactose, ({sup 3}H)fucose, ({sup 3}H)mannosamine, or phenyl-alpha-(6-{sup 3}H) N-acetylgalactosamine. UDP-Gal:GalNAc-beta 1,3-galactosyltransferase was inhibited by aryl-N-acetyl-alpha-galactosaminides but not by a number of other aryl-glycosides. Treatment with these inhibitors also causes reversible morphologic changes including formation of intercellular cysts. Aryl-N-acetyl-alpha-galactosaminides can be useful for the structural and functional studies of mucin macromolecules and other O-linked glycoproteins.

  17. Increasing 3alpha,5alpha-THP following inhibition of neurosteroid biosynthesis in the ventral tegmental area reinstates anti-anxiety, social, and sexual behavior of naturally receptive rats.

    Science.gov (United States)

    Frye, Cheryl A; Paris, Jason J; Rhodes, Madeline E

    2009-01-01

    The progesterone metabolite and neurosteroid, 5alpha-pregnan-3alpha-ol-20-one (3alpha,5alpha-THP), has actions in the midbrain ventral tegmental area (VTA) to modulate lordosis, but its effects on other reproductively relevant behaviors are not well understood. Effects on exploration, anxiety, and social behavior resulting from inhibition of 3alpha,5alpha-THP formation, as well as 3alpha,5alpha-THP enhancement, were investigated in the midbrain VTA. Naturally sexually receptive, female rats (n=8-10/group) received infusions aimed at the midbrain VTA of vehicle, PK11195 (an inhibitor of neurosteroidogenesis), and/or indomethacin (an inhibitor of 3alpha,5alpha-THP formation from prohormones), and were subsequently infused with vehicle or FGIN 1-27 (a neurosteroidogenesis enhancer). The rats were then assessed in a behavioral battery that examined exploration (open field), anxiety (elevated plus maze), social (social interaction), and sexual (paced mating) behavior. Inhibition of 3alpha,5alpha-THP formation decreased exploratory, anti-anxiety, social, and sexual behavior, as well as midbrain 3alpha,5alpha-THP levels. Infusions of FGIN 1-27 following 3alpha,5alpha-THP inhibition restored these behaviors and midbrain 3alpha,5alpha-THP levels to those commensurate with control rats that had not been administered inhibitors. These findings suggest that 3alpha,5alpha-THP formation in the midbrain VTA may influence appetitive, as well as consummatory, aspects of mating behavior.

  18. Involvement of prostaglandin F2alpha in the adverse effect of PCB 77 on the force of contractions of bovine myometrium.

    Science.gov (United States)

    Wrobel, Michal H; Rekawiecki, Robert; Kotwica, Jan

    2009-08-21

    Polychlorinated biphenyls (PCBs) stimulate in vitro both the force of myometrial contractions and endometrial secretion of PGF2alpha in cattle. Therefore, the goal of this study was to investigate the participation of PGF2alpha in the effect of PCBs on uterine contractility. For this aim, the myometrial strips were incubated (48h) with PCB 77 at the dose of 1, 10 and 100ng/ml (i.e., 0.0034, 0.034 and 0.34nmol/ml) separately or jointly with indomethacin (INDO, 10(-4)M), which blocks the PGF2alpha synthesis. Next, the force of myometrial strips contractions was measured. Further, the influence of PCB 77 (0.1, 1 and 10ng/ml) on the PGF2alpha secretion from myometrial cells after 6, 24, and 48h and PCB 77 (1 and 10ng/ml) on the mRNA expression of cyclooxygenase 2 (COX-2) and PGF2alpha synthase (PGFS) in myometrial cells after 6 and 24h, was investigated. The increase (P<0.05-0.001) of the contractions force of myometrial strips evoked by each dose of PCB 77, was markedly reduced (P<0.05-001) by INDO. There was an increase (P<0.05-0.001) of both PGF2alpha secretion after all studied periods of cell incubation and mRNA expression for COX-2 and PGFS after 6h treatment of myometrial cells with PCB 77. It can be concluded that myometrial synthesis of PGF2alpha and its further secretion is a part of the mechanism by means of which PCB 77 may affect the force of myometrial contractions in cattle.

  19. Intraluteal prostaglandin biosynthesis and signaling are selectively directed towards PGF2alpha during luteolysis but towards PGE2 during the establishment of pregnancy in sheep.

    Science.gov (United States)

    Lee, JeHoon; McCracken, John A; Stanley, Jone A; Nithy, Thamizh K; Banu, Sakhila K; Arosh, Joe A

    2012-10-01

    In ruminants, endometrial prostalgandin (PG) F(2alpha) causes functional luteolysis, whereas luteal synthesis of PGF(2alpha) is required for structural luteolysis. PGE(2) is considered to be a luteoprotective mediator. Molecular aspects of luteal PGF(2alpha) and PGE(2) biosynthesis and signaling during the estrous cycle and establishment of pregnancy are largely unknown. The objectives of the present study were 1) to determine the regulation of proteins involved in PGF(2alpha) and PGE(2) biosynthesis, catabolism, transport and signaling in the corpus luteum (CL); 2) to investigate the transport of interferon tau (IFNT), PGF(2alpha), and PGE(2) from the uterus to the ovary through the vascular utero-ovarian plexus (UOP); and 3) to compare the intraluteal production of PGF(2alpha) and PGE(2) on Days 12, 14, and 16 of the estrous cycle and pregnancy in sheep. Our results indicate that luteal PG biosynthesis is selectively directed towards PGF(2alpha) at the time of luteolysis and towards PGE(2) during the establishment of pregnancy. Moreover, the ability of the CL of early pregnancy to resist luteolysis is due to increased intraluteal biosynthesis of PGE(2) and PGE(2) receptor (PTGER) 2 (also known as EP2)- and PTGER4 (also known as EP4)-mediated signaling. We also found that IFNT protein is not transported through the UOP from the uterus to the ovary; in contrast, a large proportion of endometrial PGE(2) is transported from the uterus to the ovary through the UOP. These results indicate that endometrial PGE(2) stimulated by pregnancy is transported locally to the ovary, which increases luteal PGE(2) biosynthesis and hence activates luteal PTGER2 and PTGER4 signaling, thus protecting the CL during the establishment of pregnancy in sheep.

  20. Antidiabetic property of Symplocos cochinchinensis is mediated by inhibition of alpha glucosidase and enhanced insulin sensitivity.

    Directory of Open Access Journals (Sweden)

    Kalathookunnel Antony Antu

    Full Text Available The study is designed to find out the biochemical basis of antidiabetic property of Symplocos cochinchinensis (SC, the main ingredient of 'Nisakathakadi' an Ayurvedic decoction for diabetes. Since diabetes is a multifactorial disease, ethanolic extract of the bark (SCE and its fractions (hexane, dichloromethane, ethyl acetate and 90% ethanol were evaluated by in vitro methods against multiple targets relevant to diabetes such as the alpha glucosidase inhibition, glucose uptake, adipogenic potential, oxidative stress, pancreatic beta cell proliferation, inhibition of protein glycation, protein tyrosine phosphatase-1B (PTP-1B and dipeptidyl peptidase-IV (DPP-IV. Among the extracts, SCE exhibited comparatively better activity like alpha glucosidase inhibition (IC50 value-82.07 ± 2.10 µg/mL, insulin dependent glucose uptake (3 fold increase in L6 myotubes, pancreatic beta cell regeneration in RIN-m5F (3.5 fold increase and reduced triglyceride accumulation (22% decrease in 3T3L1 cells, protection from hyperglycemia induced generation of reactive oxygen species in HepG2 cells (59.57% decrease with moderate antiglycation and PTP-1B inhibition. Chemical characterization by HPLC revealed the superiority of SCE over other extracts due to presence and quantity of bioactives (beta-sitosterol, phloretin 2'glucoside, oleanolic acid in addition to minerals like magnesium, calcium, potassium, sodium, zinc and manganese. So SCE has been subjected to oral sucrose tolerance test to evaluate its antihyperglycemic property in mild diabetic and diabetic animal models. SCE showed significant antihyperglycemic activity in in vivo diabetic models. We conclude that SC mediates the antidiabetic activity mainly via alpha glucosidase inhibition, improved insulin sensitivity, with moderate antiglycation and antioxidant activity.

  1. Human alpha galactosidase and alpha 1,2fucosyltransferase concordantly inhibit xenoreactivity of NIH 3T3 cells with human serum

    Institute of Scientific and Technical Information of China (English)

    YANJing-Lian; YULu-Yang; GUOLi-He

    2003-01-01

    AIM: To study the influence of the expression of human alpha galactosidase and alphal,2 fucosyltransferase on Galalpha 1,3 Gal and consequent xenoreactivity in NIH3T3 cells. METHODS: The expression levels of G antigen andH antigen and binding of human natural antibodies (IgG and IgM) and complement (C3c) to NIH3T3 cells wereanalyzed by flow cytometry. Western blot was employed to further determine the expression of glycoproteins of Gantigen. Cytolysis assay with normal human serum was performed by MTT assay. RESULTS: Western blotshowed that glycoproteins with molecular weight of 107 kDa, 98 kDa, 88 kDa, 56 kDa, 40 kDa, and 37 kDa wereinhibited and even abrogated totally in alpha galactosidase transfectants and alpha 1,2 fucosyltransferase transfectants.The combined transfection of the two enzymes led to a much stronger inhibition of the glycoproteins. The bindingof Gs-IB4 was decreased by 57.4% in alpha galactosidase transfectants, 28.8% in alpha 1,2 fucosyltransferasetransfectants, and 72.1% in combined transfectants, respectively. In contrast, UEA-1 binding was increased about6.7-fold, 6.0-fold, and 8.0-fold respectively. The xenoreactivity with human IgG was also reduced by 61.4%, 67.0%,and 73.4%, respectively in the three kinds of transfectants. The resistance to cytolysis mediated by human serumwas enhanced by 42.4% in alpha galactosidase transfectants, 51.9% in alpha 1,2 fucosyltranferase, and even65.5% in the combined transfectants. CONCLUSION: Although alpha galactosidase and alpha 1,2 fucosyltransferasehad different biochemical properties, they could inhibit the expression of Gal alpha 1,3 Gal synergistically, leading tostronger resistance of xenograft against cytolysis.

  2. Molecular cloning and expression of rat prostaglandin E receptor EP2 subtype.

    Science.gov (United States)

    Sando, T; Usui, T; Tanaka, I; Mori, K; Sasaki, Y; Fukuda, Y; Namba, T; Sugimoto, Y; Ichikawa, A; Narumiya, S

    1994-05-16

    A cDNA clone encoding the rat prostaglandin (PG) E receptor EP2 subtype was cloned from a rat lung cDNA library. It encodes 488 amino acid residues with putative seven-transmembrane domains. Specific binding of [3H]PGE2 was found in COS-7 cells transfected with the cDNA and was displaced with unlabeled prostaglandins in the order of PGE2 = PGE1 > iloprost > or = PGF2 alpha > or = PGD2. The binding was also inhibited by misoprostol, an EP2 and EP3 agonist, but not by sulprostone, an EP1 and EP3 agonist. Northern blot analysis demonstrated that the EP2 mRNA is widely expressed in various tissues, the significant expression being observed in the thymus, lung, spleen, heart stomach, and pancreas.

  3. Oligomeric procyanidins of French maritime pine bark extract (Pycnogenol) effectively inhibit alpha-glucosidase.

    Science.gov (United States)

    Schäfer, Angelika; Högger, Petra

    2007-07-01

    The standardized maritime pine bark extract (Pycnogenol) was reported to exert clinical anti-diabetic effects after peroral intake. However, an increased insulin secretion was not observed after administration of the extract to patients. Our aim was to elucidate whether the described clinical effects of Pycnogenol are related to inhibition of alpha-glucosidase. Therefore, we analyzed the inhibitory activity of Pycnogenol, green tea extract and acarbose towards alpha-glucosidase. Furthermore, we explored different fractions of Pycnogenol containing compounds of diverse molecular masses from polyphenolic monomers, dimers and higher oligomers to uncover which components exhibited the most pronounced inhibitory activity. We found that Pycnogenol exhibited the most potent inhibition (IC(50) about 5 microg/mL) on alpha-glucosidase compared to green tea extract (IC(50) about 20 microg/mL) and acarbose (IC(50) about 1mg/mL). The inhibitory action of Pycnogenol was stronger in extract fractions containing higher procyanidin oligomers. The results obtained assign a novel, local effect to oligomeric procyanidins and contribute to the explanation of glucose-lowering effects of Pycnogenol observed in clinical trials with diabetic patients.

  4. Inhibition of HIF-1{alpha} activity by BP-1 ameliorates adjuvant induced arthritis in rats

    Energy Technology Data Exchange (ETDEWEB)

    Shankar, J. [Department of Microbiology and Immunology, University of Illinois at Chicago, Chicago (United States); Thippegowda, P.B., E-mail: btprabha@uic.edu [Department of Pharmacology, (M/C 868), College of Medicine, University of Illinois at Chicago, 835 S. Wolcott Ave., Chicago, IL 60612 (United States); Kanum, S.A. [Department of Chemistry, Yuvaraj' s College, University of Mysore, Mysore (India)

    2009-09-18

    Rheumatoid arthritis (RA) is a chronic inflammatory, angiogenic disease. Inflamed synovitis is a hallmark of RA which is hypoxic in nature. Vascular endothelial growth factor (VEGF), one of the key regulators of angiogenesis, is overexpressed in the pathogenesis of RA. VEGF expression is regulated by hypoxia-inducible factor-1{alpha} (HIF-1{alpha}), a master regulator of homeostasis which plays a pivotal role in hypoxia-induced angiogenesis. In this study we show that synthetic benzophenone analogue, 2-benzoyl-phenoxy acetamide (BP-1) can act as a novel anti-arthritic agent in an experimental adjuvant induced arthritis (AIA) rat model by targeting VEGF and HIF-1{alpha}. BP-1 administered hypoxic endothelial cells and arthritic animals clearly showed down regulation of VEGF expression. Further, BP-1 inhibits nuclear translocation of HIF-1{alpha}, which in turn suppresses transcription of the VEGF gene. These results suggest a further possible clinical application of the BP-1 derivative as an anti-arthritic agent in association with conventional chemotherapeutic agents.

  5. Sclareol protects Staphylococcus aureus-induced lung cell injury via inhibiting alpha-hemolysin expression.

    Science.gov (United States)

    Ouyang, Ping; Sun, Mao; He, Xuewen; Wang, Kaiyu; Yin, Zhongqiong; Fu, Hualin; Li, Yinglun; Geng, Yi; Shu, Gang; He, Changliang; Liang, Xiaoxia; Lai, Weiming; Li, Lixia; Zou, Yuanfeng; Song, Xu; Yin, Lizi

    2016-09-23

    Staphylococcus aureus (S. aureus) is a common Gram-positive bacterium that causes serious infections in human and animals. With the continuous emergence of the methicillin-resistant S. aureus (MRSA) strains, antibiotics have limited efficacy in treating MRSA infections. Accordingly, novel agents that act on new targets are desperately needed to combat these infections. S. aureus alpha-hemolysin plays an indispensable role in its pathogenicity. In this study, we demonstrate that sclareol, a fragrant chemical compound found in clary sage, can prominently decrease alpha-hemolysin secretion in S. aureus strain USA300 at sub-inhibitory concentrations. Hemolysis assays, western-blotting and RT-PCR were used to detect the production of alpha-hemolysin in the culture supernatant. When USA300 was co-cultured with and A549 epithelial cells, sclareol could protect A549 cells at a final concentration of 8 µg/ml. The protective capability of sclareol against the USA300-mediated injury of A549 cells was further shown by cytotoxicity assays and live/dead analysis. In conclusion, sclareol was shown to inhibit the production of S. aureus alpha-hemolysin. Sclareol has potential for development as a new agent to treat S. aureus infections.

  6. DeltaNp73alpha regulates MDR1 expression by inhibiting p53 function.

    Science.gov (United States)

    Vilgelm, A; Wei, J X; Piazuelo, M B; Washington, M K; Prassolov, V; El-Rifai, W; Zaika, A

    2008-04-01

    The p73 protein is a transcription factor and member of the p53 protein family that expresses as a complex variety of isoforms. DeltaNp73alpha is an N-terminally truncated isoform of p73. We found that DeltaNp73 protein is upregulated in human gastric carcinoma suggesting that DeltaNp73 may play an oncogenic role in these tumors. Although it has been shown that DeltaNp73alpha inhibits apoptosis and counteracts the effect of chemotherapeutic drugs, the underlying mechanism by which this p73 isoform contributes to chemotherapeutic drug response remains to be explored. We found that DeltaNp73alpha upregulates MDR1 mRNA and p-glycoprotein (p-gp), which is involved in chemotherapeutic drug transport. This p-gp upregulation was accompanied by increased p-gp functional activity in gastric cancer cells. Our data suggest that upregulation of MDR1 by DeltaNp73alpha is mediated by interaction with p53 at the MDR1 promoter.

  7. Inhibition of IkappaB kinase alpha (IKK{alpha}) or IKKbeta (IKK{beta}) plus forkhead box O (Foxo) abolishes skeletal muscle atrophy

    Energy Technology Data Exchange (ETDEWEB)

    Reed, S.A. [Department of Physical Therapy, University of Florida, 101 S. Newell Drive, Gainesville, FL 32610 (United States); Senf, S.M. [Department of Applied Physiology and Kinesiology, University of Florida, 25 Stadium Road, Gainesville, FL 32610 (United States); Cornwell, E.W.; Kandarian, S.C. [Department of Health Sciences, Boston University, 635 Commonwealth Avenue, Boston, MA 02215 (United States); Judge, A.R., E-mail: arjudge@phhp.ufl.edu [Department of Physical Therapy, University of Florida, 101 S. Newell Drive, Gainesville, FL 32610 (United States)

    2011-02-18

    Research highlights: {yields} Independent inhibition of Foxo, IKK{alpha} and IKK{beta} activities does not alter muscle fiber size in weight bearing muscles. {yields} Inhibition of Foxo activity plus IKK{alpha} or IKK{beta} activities increases muscle fiber size. {yields} Independent inhibition of Foxo and IKK{beta} activities attenuates cast immobilization-induced muscle fiber atrophy. {yields} Disuse muscle fiber atrophy is abolished by inhibition of Foxo activity plus IKK{alpha} or IKK{beta} activities. -- Abstract: Two transcription factor families that are activated during multiple conditions of skeletal muscle wasting are nuclear factor {kappa}B (NF-{kappa}B) and forkhead box O (Foxo). There is clear evidence that both NF-{kappa}B and Foxo activation are sufficient to cause muscle fiber atrophy and they are individually required for at least half of the fiber atrophy during muscle disuse, but there is no work determining the combined effect of inhibiting these factors during a physiological condition of muscle atrophy. Here, we determined whether inhibition of Foxo activation plus inhibition of NF-{kappa}B activation, the latter by blocking the upstream inhibitor of kappaB kinases (IKK{alpha} and IKK{beta}), would prevent muscle atrophy induced by 7 days of cast immobilization. Results were based on measurements of mean fiber cross-sectional area (CSA) from 72 muscles transfected with 5 different mutant expression plasmids or plasmid combinations. Immobilization caused a 47% decrease in fiber CSA in muscles injected with control plasmids. Fibers from immobilized muscles transfected with dominant negative (d.n.) IKK{alpha}-EGFP, d.n. IKK{beta}-EGFP or d.n. Foxo-DsRed showed a 22%, 57%, and 76% inhibition of atrophy, respectively. Co-expression of d.n. IKK{alpha}-EGFP and d.n. Foxo-DsRed significantly inhibited 89% of the immobilization-induced fiber atrophy. Similarly, co-expression of d.n. IKK{beta}-EGFP and d.n. Foxo-DsRed inhibited the immobilization

  8. In-vitro cancer cell cytotoxicity and alpha amylase inhibition effect of seven tropical fruit residues

    Institute of Scientific and Technical Information of China (English)

    Priti Gupta; Ira Bhatnagar; Se-Kwon Kim; Ajay Kumar Verma; Anubhuti Sharma

    2014-01-01

    Objective:To determine quantitative phytochemical, anticancer and antidiabetic effect of seven Indian tropical fruit residues. Methods:In-vitro cytotoxic activity (IC50) was evaluated against cervical cancer cells (HeLa), breast cancer cells (MCF-7), hepatocellular carcinoma cells (HepG-2) and bone sarcoma cells (MG-63) and alpha amylase inhibition assay was used for antidiabetic activity. Results: Results of phytochemical analysis revealed that all residues contained remarkable amount of alkaloid, saponin, tannin and flavonoid. Notable cancer cell growth inhibition was observed for the extract from Carissa carandas pomace and Litchi sinensis seeds with IC50 values ranged from 56.72 to 89.24 μg/mL. Alpha amylase inhibition assay was measured at six different concentrations (5, 10, 25, 50, 100 and 200 mg/mL) by using different solvent extract. Results showed that Carissa carandas possessed best activity with IC50 value as 29.66 mg/mL followed by other residues in methanol extract. Conclusions:Study suggests that these fruit residues demonstrate promising antidiabetic and anticancer activity that substantiated its ethno medicinal use and may provide new molecules for the treatment of these diseases.

  9. Ex-vivo in-vitro inhibition of lipopolysaccharide stimulated tumor necrosis factor-alpha and interleukin-1 beta secretion in human whole blood by extractum urticae dioicae foliorum.

    Science.gov (United States)

    Obertreis, B; Ruttkowski, T; Teucher, T; Behnke, B; Schmitz, H

    1996-04-01

    An extract of Urtica dioica folium (IDS 23, Rheuma-Hek), monographed positively for adjuvant therapy of rheumatic diseases and with known effects in partial inhibition of prostaglandin and leukotriene synthesis in vitro, was investigated with respect to effects of the extract on the lipopolysaccharide (LPS) stimulated secretion of proinflammatory cytokines in human whole blood of healthy volunteers. In the assay system used, LPS stimulated human whole blood showed a straight increase of tumor necrosis factor-alpha (TNF-alpha) and interleukin-1 beta (IL-1 beta) secretion reaching maximum concentrations within 24 h following a plateau and slight decrease up to 65 h, respectively. The concentrations of these cytokines was strongly positively correlated with the number of monocytes/macrophages of each volunteer. TNF-alpha and IL-1 beta concentration after LPS stimulation was significantly reduced by simultaneously given IDS 23 in a strictly dose dependent manner. At time 24 h these cytokine concentrations were reduced by 50.8% and 99.7%, respectively, using the highest test IDS 23 assay concentration of 5 mg/ml (p < 0.001). After 65 h the corresponding inhibition was 38.9% and 99.9%, respectively (p < 0.001). On the other hand IDS 23 showed no inhibition but stimulated IL-6 secretion in absence of LPS alone. Simultaneously given LPS and IDS 23 resulted in no further increase. In contrast to described effects on arachidonic acid cascade in vitro, tested Urtica dioica phenol carbon acid derivates and flavonoides such as caffeic malic acid, caffeic acid, chlorogenic acid, quercetin and rutin did not influence LPS stimulated TNF-alpha, IL-1 beta and IL-6 secretion in tested concentrations up to 5 x 10(-5) mol/l. These further findings on the pharmacological mechanism of action of Urticae dioica folia may explain the positive effects of this extract in the treatment of rheumatic diseases.

  10. Inhibition of lipopolysaccharide-induced nitric oxide and prostaglandin E2 production by chloroform fraction of Cudrania tricuspidata in RAW 264.7 macrophages

    OpenAIRE

    Yang Gabsik; Lee Kyungjin; Lee Mihwa; Ham Inhye; Choi Ho-Young

    2012-01-01

    Abstract Background Cudrania tricuspidata extract is an important traditional herbal remedy for tumors, inflammation, gastritis, and liver damage and is predominantly used in Korea, China, and Japan. However, the anti-inflammatory effects of the extract have not yet been conclusively proved. Methods In this study, we investigated the effects of the CHCl3 fraction (CTC) of a methanol extract of C. tricuspidata on the lipopolysaccharide (LPS)-induced nitric oxide (NO) and prostaglandin E2 (PGE2...

  11. Alpha-lipoic acid protects cardiomyocytes against hypoxia/reoxygenation injury by inhibiting autophagy

    Energy Technology Data Exchange (ETDEWEB)

    Cao, Xueming; Chen, Aihua, E-mail: aihuachen2012@sina.com; Yang, Pingzhen; Song, Xudong; Liu, Yingfeng; Li, Zhiliang; Wang, Xianbao; Wang, Lizi; Li, Yunpeng

    2013-11-29

    Highlights: •We observed the cell viability and death subjected to H/R in H9c2 cardiomyocytes. •We observed the degree of autophagy subjected to H/R in H9c2 cardiomyocytes. •LA inhibited the degree of autophagy in parallel to the enhanced cell survival. •LA inhibited the autophagy in parallel to the decreased total cell death. •We concluded that LA protected cardiomyocytes against H/R by inhibiting autophagy. -- Abstract: Hypoxia/reoxygenation (H/R) is an important in vitro model for exploring the molecular mechanisms and functions of autophagy during myocardial ischemia/reperfusion (I/R). Alpha-lipoic acid (LA) plays an important role in the etiology of cardiovascular disease. Autophagy is widely implicated in myocardial I/R injury. We assessed the degree of autophagy by pretreatment with LA exposed to H/R in H9c2 cell based on the expression levels of Beclin-1, LC3II/LC3I, and green fluorescent protein-labeled LC3 fusion proteins. Autophagic vacuoles were confirmed in H9c2 cells exposed to H/R using transmission electron microscopy. Our findings indicated that pretreatment with LA inhibited the degree of autophagy in parallel to the enhanced cell survival and decreased total cell death in H9c2 cells exposed to H/R. We conclude that LA protects cardiomyocytes against H/R injury by inhibiting autophagy.

  12. Tumor necrosis factor-alpha inhibits pre-osteoblast differentiation through its type-1 receptor.

    Science.gov (United States)

    Abbas, Sabiha; Zhang, Yan-Hong; Clohisy, John C; Abu-Amer, Yousef

    2003-04-01

    Tumor necrosis factor-alpha (TNF) is a pro-inflammatory cytokine with a profound role in many skeletal diseases. The cytokine has been described as a mediator of bone loss in osteolysis and other inflammatory bone diseases. In addition to its known bone resorptive action, TNF reduces bone formation by inhibiting osteoblast differentiation. Using primary and transformed osteoblastic cells, we first document that TNF inhibits expression of alkaline phosphatase and matrix deposition, both considered markers of osteoblast differentiation. The effects are dose- and time-dependent. Core-binding factor A1 (cbfa1) is a transcription factor critical for osteoblast differentiation, and we show here that it is activated by the osteoblast differentiation agent, beta-glycerophosphate. Therefore, we investigated whether the inhibitory effects of TNF were associated with altered activity of this transcription factor. Using retardation assays, we show that TNF significantly inhibits cbfal activation by beta-glycerophosphate, manifested by reduced DNA-binding activity. Next, we turned to determine the signaling pathway by which TNF inhibits osteoblast differentiation. Utilizing animals lacking individual TNF receptors, we document that TNFr1 is required for transmitting the cytokine's inhibitory effect. In the absence of this receptor, TNF failed to impact all osteoblast differentiation markers tested. In summary, TNF blocks expression of osteoblast differentiation markers and inhibits beta-glycerophosphate-induced activation of the osteoblast differentiation factor cbfa1. Importantly, these effects are mediated via a mechanism requiring the TNF type-1 receptor.

  13. Lonicera japonica-induced inhibition of interleukin-1 beta thermogenesis and E-type prostaglandin receptor-3 expression in the preoptic area of rabbits

    Institute of Scientific and Technical Information of China (English)

    Jun Dong; Rongbo Tu; Rui Pan; Xinhua Xie

    2008-01-01

    BACKGROUND:It has been shown that interleukin-1β(IL-I β)can induce fever by activating vascular endothelial cells and macrophages of the supraoptic crest to generate prostaglandin E2,which binds with receptors of the thermo-sensitive hypothalamic neurons.Lonicera japonica is one of the medicinal plants used widely in Asia for its antipyretic properties.However,these mechanisms have not yet been intensively studied.OBJECTIVE:To investigate the antipyretic effect and mechanisms of Lonicera japonica on IL-1 β-induced febrile New Zealand rabbits by observing expression changes of E-type prostaglandin receptor-3 (EP3)mRNA in the preoptic anterior hypothalamus(POAH). DESIGN:A randomized controlled study. SETTING:Electrophysiological Laboratory at the Department of Pathophysiology,Medical College of Jinan University; Department of Orthopaedics,First Hospital Affiliated to Medical College of Jinan University. MATERIALS:The experiment was performed from April to December 2005,using a total of 32 New Zealand white rabbits of both sexes,weighing 1.5-2.0 kg.All the animal experiments were performed according to the internationally accepted ethical guidelines.Lonicera japonica injection was purchased from Huanghe pharmaceutical factory of Xi'an,China.IL-1 β was purchased from Sigma,USA.METHODS:A total of 32 rabbits were divided randomly into four groups:①Normal saline(NS)control group; ②Lonicerajaponica treatment group;③IL-1 β treatment group; and ④Lonicerajaponica plus IL-1 β treatment group.In the first 3 groups,the rabbits were given separate intravenous(I.v.)injections of 1 mL NS,1 mL l.Lonicera japonica,and 100 ng IL-1 β(dissolved in 0.9% NS without pyrogen).In the lonicera japonica plus IL-I βgroup each rabbit was given I.v.injections of l mL NS and,30 minutes later, 100 ng IL-I β. MAIN OUTCOME MEASURES:Colonic temperature of each rabbit was measured at 0,10,20,30,40,50, 60,and 70 minutes after injection and the maximum temperature rise( △ T)and the

  14. Heat shock inhibits. alpha. -amylase synthesis in barley aleurone without inhibiting the activity of endoplasmic reticulum marker enzymes

    Energy Technology Data Exchange (ETDEWEB)

    Sticher, L.; Biswas, A.K.; Bush, D.S.; Jones, R.L. (Univ. of California, Berkeley (USA))

    1990-02-01

    The effects of heat shock on the synthesis of {alpha}-amylase and on the membranes of the endoplasmic reticulum (ER) of barley (Hordeum vulgare) aleurone were studied. Heat shock, imposed by raising the temperature of incubation from 25{degree}C to 40{degree}C for 3 hours, inhibits the accumulation of {alpha}-amylase and other proteins in the incubation medium of barley aleurone layers treated with gibberellic acid and Ca{sup 2+}. When ER is isolated from heat-shocked aleurone layers, less newly synthesized {alpha}-amylase is found associated with this membrane system. ER membranes, as indicated by the activities of NADH cytochrome c reductase and ATP-dependent Ca{sup 2+} transport, are not destroyed by heat stress, however. Although heat shock did not reduce the activity of ER membrane marker enzymes, it altered the buoyant density of these membranes. Whereas ER from control tissue showed a peak of marker enzyme activity at 27% to 28% sucrose (1.113-1.120 grams per cubic centimeter), ER from heat-shocked tissue peaked at 30% to 32% sucrose (1.127-1.137 grams per cubic centimeter). The synthesis of a group of proteins designated as heat-shock proteins (HSPs) was stimulated by heat shock. These HSPs were localized to different compartments of the aleurone cell. Several proteins ranging from 15 to 30 kilodaltons were found in the ER and the mitochondrial/plasma membrane fractions of heat-shocked cells, but none of the HSPs accumulated in the incubation medium of heat-shocked aleurone layers.

  15. /sup 45/Ca efflux for myometrial cells: comparison of the effects of prostaglandin F/sub 2/. cap alpha. (PGF/sub 2/), oxytocin (OT) and arachidonate (A)

    Energy Technology Data Exchange (ETDEWEB)

    Katona, G.; Molnar, M.; Toth, M.; Hertelendy, F.

    1986-03-01

    The aim of this study was to measure PGF/sub 2..cap alpha../-induced Ca/sup 2 +/ release from uterine cells and to compare this to the actions of OT and A. Smooth muscle cells isolated from the uterus (shell gland) of laying hens were cultured for 7 days in M199 plus 10% fetal calf serum. The cells were treated with digitonin (20..mu..M) and preloaded with /sup 45/Ca for 40 min. Addition of PGF/sub 2..cap alpha../ caused a biphasic /sup 45/Ca-efflux. There was a small but significant /sup 45/Ca-release within 30 sec (rapid phase) followed by a larger one within 7 min (slow phase). In comparison, both OT and A stimulated /sup 45/Ca efflux during a single, slow phase. The maximal effect of A was observed at < 7 min, whereas that of OT was slower, peaking after 7 min. Mepacrin, an inhibitor of A release, attenuated the action of OT without having any effect on A promoted /sup 45/Ca-efflux. Indomethacin, an inhibitor of PG synthase, failed to suppress the Ca-releasing effect of A suggesting the A itself or a lipoxygenase product may have been responsible for the observed effects. Moreover, these results provide suggestive evidence that A release is an important step in the action of various uterotonic agents converging on the mobilization of intracellular Ca.

  16. Prostaglandins are important in thermoregulation of a reptile (Pogona vitticeps).

    Science.gov (United States)

    Seebacher, Frank; Franklin, Craig E

    2003-08-07

    The effectiveness of behavioural thermoregulation in reptiles is amplified by cardiovascular responses, particularly by differential rates of heart beat in response to heating and cooling (heart-rate hysteresis). Heart-rate hysteresis is ecologically important in most lineages of ectothermic reptile, and we demonstrate that heart-rate hysteresis in the lizard Pogona vitticeps is mediated by prostaglandins. In a control treatment (administration of saline), heart rates during heating were significantly faster than during cooling at any given body temperature. When cyclooxygenase 1 and 2 enzymes were inhibited, heart rates during heating were not significantly different from those during cooling. Administration of agonists showed that thromboxane B(2) did not have a significant effect on heart rate, but prostacyclin and prostaglandin F(2alpha) caused a significant increase (3.5 and 13.6 beats min(-1), respectively) in heart rate compared with control treatments. We speculate that heart-rate hysteresis evolved as a thermoregulatory mechanism that may ultimately be controlled by neurally induced stimulation of nitric oxide production, or maybe via photolytically induced production of vitamin D.

  17. The TF1-ATPase and ATPase activities of assembled alpha 3 beta 3 gamma, alpha 3 beta 3 gamma delta, and alpha 3 beta 3 gamma epsilon complexes are stimulated by low and inhibited by high concentrations of rhodamine 6G whereas the dye only inhibits the alpha 3 beta 3, and alpha 3 beta 3 delta complexes.

    Science.gov (United States)

    Paik, S R; Yokoyama, K; Yoshida, M; Ohta, T; Kagawa, Y; Allison, W S

    1993-12-01

    The ATPase activity of the F1-ATPase from the thermophilic bacterium PS3 is stimulated at concentrations of rhodamine 6G up to about 10 microM where 70% stimulation is observed at 36 degrees C. Half maximal stimulation is observed at about 3 microM dye. At rhodamine 6G concentrations greater than 10 microM, ATPase activity declines with 50% inhibition observed at about 75 microM dye. The ATPase activities of the alpha 3 beta 3 gamma and alpha 3 beta 3 gamma delta complexes assembled from isolated subunits of TF1 expressed in E. coli deleted of the unc operon respond to increasing concentrations of rhodamine 6G nearly identically to the response of TF1. In contrast, the ATPase activities of the alpha 3 beta 3 and alpha 3 beta 3 delta complexes are only inhibited by rhodamine 6G with 50% inhibition observed, respectively, at 35 and 75 microM dye at 36 degrees C. The ATPase activity of TF1 is stimulated up to 4-fold by the neutral detergent, LDAO. In the presence of stimulating concentrations of LDAO, the ATPase activity of TF1 is no longer stimulated by rhodamine 6G, but rather, it is inhibited with 50% inhibition observed at about 30 microM dye at 30 degrees C. One interpretation of these results is that binding of rhodamine 6G to a high-affinity site on TF1 stimulates ATPase activity and unmasks a low-affinity, inhibitory site for the dye which is also exposed by LDAO.

  18. Angiotensin II and renal prostaglandin release in the dog. Interactions in controlling renal blood flow and glomerular filtration rate.

    Science.gov (United States)

    Bugge, J F; Stokke, E S

    1994-04-01

    The relationship between angiotensin II and renal prostaglandins, and their interactions in controlling renal blood flow (RBF) and glomerular filtration rate (GFR) were investigated in 18 anaesthetized dogs with acutely denervated kidneys. Intrarenal angiotensin II infusion increased renal PGE2 release (veno-arterial concentration difference times renal plasma flow) from 1.7 +/- 0.9 to 9.1 +/- 0.4 and 6-keto-PGF1 alpha release from 0.1 +/- 0.1 to 5.3 +/- 2.1 pmol min-1. An angiotensin II induced reduction in RBF of 20% did not measurably change GFR whereas a 30% reduction reduced GFR by 18 +/- 8%. Blockade of prostaglandin synthesis approximately doubled the vasoconstrictory action of angiotensin II, and all reductions in RBF were accompanied by parallel reductions in GFR. When prostaglandin release was stimulated by infusion of arachidonic acid (46.8 +/- 13.3 and 15.9 +/- 5.4 pmol min-1 for PGE2, and 6-keto-PGF1 alpha, respectively), angiotensin II did not change prostaglandin release, but had similar effects on the relationship between RBF and GFR as during control. In an ureteral occlusion model with stopped glomerular filtration measurements of ureteral pressure and intrarenal venous pressure permitted calculations of afferent and efferent vascular resistances. Until RBF was reduced by 25-30% angiotensin II increased both afferent and efferent resistances almost equally, keeping the ureteral pressure constant. At greater reductions in RBF, afferent resistance increased more than the efferent leading to reductions in ureteral pressure. This pattern was not changed by blockade of prostaglandin synthesis indicating no influence of prostaglandins on the distribution of afferent and efferent vascular resistances during angiotensin II infusion. In this ureteral occlusion model glomerular effects of angiotensin II will not be detected, and it might well be that the shift from an effect predominantly on RBF to a combined effect on both RBF and GFR induced by inhibition

  19. Effects of Common Pesticides on Prostaglandin D2 (PGD2) Inhibition in SC5 Mouse Sertoli Cells, Evidence of Binding at the COX-2 Active Site, and Implications for Endocrine Disruption

    Science.gov (United States)

    Kugathas, Subramaniam; Audouze, Karine; Ermler, Sibylle; Orton, Frances; Rosivatz, Erika; Scholze, Martin; Kortenkamp, Andreas

    2015-01-01

    . Citation: Kugathas S, Audouze K, Ermler S, Orton F, Rosivatz E, Scholze M, Kortenkamp A. 2016. Effects of common pesticides on prostaglandin D2 (PGD2) inhibition in SC5 mouse Sertoli cells, evidence of binding at the COX-2 active site, and implications for endocrine disruption. Environ Health Perspect 124:452–459; http://dx.doi.org/10.1289/ehp.1409544 PMID:26359731

  20. Diallyl trisulfide, a chemopreventive agent from Allium vegetables, inhibits alpha-secretases in breast cancer cells.

    Science.gov (United States)

    Kiesel, Violet A; Stan, Silvia D

    2017-03-18

    Breast cancer affects one in eight women throughout the course of their lifetime creating a demand for novel prevention strategies against this disease. The Notch signaling pathway is often aberrantly activated in human malignancies including breast cancer. Alpha secretases, including ADAM (A Disintegrin and Metalloprotease) -10 and -17, are proteases that play a key role in the cleavage of cell surface molecules and subsequent ligand-mediated activation of Notch signaling pathway. High expression levels of ADAM10 and 17 have been clinically associated with a lower disease-free survival in breast cancer patients. This study was undertaken to determine the effect of diallyl trisulfide (DATS), a bioactive organosulfide found in garlic and other Allium vegetables, on alpha secretases in breast cancer cells. Here we report for the first time that DATS inhibits the expression of ADAM10 and ADAM17 in estrogen-independent MDA-MB-231 and estrogen-dependent MCF-7 breast cancer cells, and in Harvey-ras (H-Ras) transformed MCF10A-H-Ras breast epithelial cells. We also show that DATS induces a dose-dependent reduction in colony formation ability of MDA-MB-231 and MCF-7 cells, suggesting a long-term effect of DATS on growth inhibition of breast cancer cells. Furthermore, we show that DATS inhibits the Notch ligands Jagged-1 and Jagged-2 involved in activation of Notch signaling pathway. Collectively, these findings show that DATS targets Notch pathway components overexpressed in breast cancer tumors and may serve as a functionally relevant bioactive for breast cancer prevention.

  1. Manassantin B isolated from Saururus chinensis inhibits cyclooxygenase-2-dependent prostaglandin D2 generation by blocking Fyn-mediated nuclear factor-kappaB and mitogen activated protein kinase pathways in bone marrow derived-mast cells.

    Science.gov (United States)

    Lu, Yue; Hwang, Seung-Lark; Son, Jong Keun; Chang, Hyeun Wook

    2013-01-01

    The authors investigated the effect of manassantin B (Man B) isolated from Saururus chinensis (S. chinensis) on cyclooxygenase-2 (COX-2)-dependent prostaglandin D2 (PGD2) generation in mouse bone marrow derived-mast cells (BMMCs). Man B inhibited the generation of PGD2 dose-dependently by inhibiting COX-2 expression in immunoglobulin E (IgE)/Ag-stimulated BMMCs. To elucidate the mechanism responsible for the inhibition of COX-2 expression by Man B, the effects of Man B on the activation of nuclear factor-kappaB (NF-κB), a transcription factor essential and mitogen-activated protein kinases (MAPKs) for COX-2 induction, were examined. Man B attenuated the nuclear translocation of NF-κB p65 and its DNA-binding activity by inhibiting inhibitors of kappa Bα (IκBα) degradation and concomitantly suppressing IκB kinase (IKK) phosphorylation. In addition, Man B suppressed phosphorylation of MAPKs including extracellular signal-regulated kinase 1/2 (ERK1/2), c-Jun NH2-terminal kinase (JNK) and p38. It was also found that Man B suppressed Fyn kinase activation and consequent downstream signaling processes, including those involving Syk, Gab2, and Akt. Taken together, the present results suggest that Man B suppresses COX-2 dependent PGD2 generation by primarily inhibiting Fyn kinase in FcεRI-mediated mast cells.

  2. Prostaglandins and prostaglandin receptor antagonism in migraine

    DEFF Research Database (Denmark)

    Antonova, Maria

    2013-01-01

    Human models of headache may contribute to understanding of prostaglandins' role in migraine pathogenesis. The current thesis investigated the migraine triggering effect of prostaglandin E2 (PGE2) in migraine patients without aura, the efficacy of a novel EP4 receptor antagonist, BGC20....... The infusion of PGE2 caused the immediate migraine-like attacks and vasodilatation of the middle cerebral artery in migraine patients without aura. The highly specific and potent EP4 receptor antagonist, BGC20-1531, was not able to attenuate PGE2-induced headache and vasodilatation of both intra- and extra......-cerebral arteries. The intravenous infusion of PGF2α did not induce headache or statistically significant vasoconstriction of cerebral arteries in healthy volunteers. Novel data on PGE2-provoked immediate migraine-like attacks suggest that PGE2 may be one of the important final products in the pathogenesis...

  3. TNF-alpha/IFN-gamma-induced iNOS expression increased by prostaglandin E2 in rat primary astrocytes via EP2-evoked cAMP/PKA and intracellular calcium signaling.

    Science.gov (United States)

    Hsiao, Han-Yun; Mak, Oi-Tong; Yang, Chung-Shi; Liu, Yu-Peng; Fang, Kuan-Ming; Tzeng, Shun-Fen

    2007-01-15

    Astrocytes, the most abundant glia in the central nervous system (CNS), produce a large amount of prostaglandin E(2) (PGE(2)) in response to proinflammatory mediators after CNS injury. However, it is unclear whether PGE(2) has a regulatory role in astrocytic activity under the inflamed condition. In the present work, we showed that PGE(2) increased inducible nitric oxide synthase (iNOS) production by tumor necrosis factor-alpha and interferon-gamma (T/I) in astrocytes. Pharmacological and RNA interference approaches further indicated the involvement of the receptor EP2 in PGE(2)-induced iNOS upregulation in T/I-treated astrocytes. Quantitative real-time polymerase chain reaction and gel mobility shift assays also demonstrated that PGE(2) increased iNOS transcription through EP2-induced cAMP/protein kinase A (PKA)-dependent pathway. Consistently, the effect of EP2 was significantly attenuated by the PKA inhibitor KT-5720 and partially suppressed by the inhibitor (SB203580) of p38 mitogen-activated protein kinase (p38MAPK), which serves as one of the downstream components of the PKA-dependent pathway. Interestingly, EP2-mediated PKA signaling appeared to increase intracellular Ca(2+) release through inositol triphosphate (IP3) receptor activation, which might in turn stimulate protein kinase C (PKC) activation to promote iNOS production in T/I-primed astrocytes. By analyzing the expression of astrocytic glial fibrillary acidic protein (GFAP), we found that PGE(2) alone only triggered the EP2-induced cAMP/PKA/p38MAPK signaling pathway in astrocytes. Collectively, PGE(2) may enhance T/I-induced astrocytic activation by augmenting iNOS/NO production through EP2-mediated cross-talk between cAMP/PKA and IP3/Ca(2+) signaling pathways.

  4. The inhibition of P338 lymphocytic leukemia DNA polymerase alpha activity by cis-diamminedichloroplatinum(II) and related derivatives.

    Science.gov (United States)

    Oswald, C B; Hall, I H

    1989-01-01

    Cis-platinum derivatives were observed to inhibit the activity of DNA polymerase alpha of P388 lymphocytic leukemia cells. A 600g nuclear preparation of the polymerase alpha was inhibited by cis-diamminedichloroplatinum(II) [cDDP], diamminemalonatoplatinum(II) [MAL], (1,2-diaminocyclohexane)-dichloroplatinum(II) [DACH-Pt-CL2], and (1,2-diaminocyclohexane)malonato-platinum(II) [DACH-Pt-MAL]. cDDP was a more potent inhibitor of the enzyme activity which was positively correlated with the observed inhibition of DNA synthesis of P388 cells in vivo and in vitro. The inhibition of the 600g preparation by cDDP could be partially reversed by the addition of exogenous ctDNA, but 35% inhibition was not retreivable by adding new template. Isolation of the P388 DNA polymerase alpha enzyme by DEAE column chromatography led to an enzyme with 100 fold purification, which was sensitive to N-ethyl maleimide at 0.1 mM concentration. cDDP inhibited the activity of this enzyme in a dose dependent manner. However, MAL, DACH-Pt-Cl2 and DACH-Pt-MAL afforded no inhibition, nor did the latter two derivatives bind to the enzyme. cDDP inhibition of the activity of purified enzyme was partially reversed by the addition of exogenous ctDNA and by the addition of dGTP, whereas addition of other d(NTP)s had no effect on the recovery of the enzyme activity. These studies suggest that cDDP inhibits DNA polymerase alpha activity and that the inhibition is not the sole mechanism of the action of the drug in suppression of DNA synthesis and cell death. Preliminary studies suggest that the drug may bind to the apoprotein of the enzyme in a competitive manner with dGTP.

  5. Essential oil of Myrtus communis inhibits inflammation in rats by reducing serum IL-6 and TNF-alpha.

    Science.gov (United States)

    Maxia, Andrea; Frau, Maria Assunta; Falconieri, Danilo; Karchuli, Manvendra Singh; Kasture, Sanjay

    2011-10-01

    The topical antiinflammatory activity of the essential oil of Myrtus communis L. was studied using croton oil induced ear edema and myeloperoxidase (MPO) activity in mice, and cotton pellet induced granuloma, and serum tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) in rats. On topical application, the oil exhibited a significant decrease in the ear edema as well as MPO activity. The oil also inhibited cotton pellet-induced granuloma and serum TNF-alpha and IL-6. It can be concluded that the essential oil of Myrtus communis reduces leukocyte migration to the damaged tissue and exhibits antiinflammatory activity.

  6. Isorhamnetin Attenuates Staphylococcus aureus-Induced Lung Cell Injury by Inhibiting Alpha-Hemolysin Expression.

    Science.gov (United States)

    Jiang, Lanxiang; Li, Hongen; Wang, Laiying; Song, Zexin; Shi, Lei; Li, Wenhua; Deng, Xuming; Wang, Jianfeng

    2016-03-01

    Staphylococcus aureus, like other gram-positive pathogens, has evolved a large repertoire of virulence factors as a powerful weapon to subvert the host immune system, among which alpha-hemolysin (Hla), a secreted pore-forming cytotoxin, plays a preeminent role. We observed a concentration-dependent reduction in Hla production by S. aureus in the presence of sub-inhibitory concentrations of isorhamnetin, a flavonoid from the fruits of Hippophae rhamnoides L., which has little antibacterial activity. We further evaluate the effect of isorhamnetin on the transcription of the Hla-encoding gene hla and RNAIII, an effector molecule in the agr system. Isorhamnetin significantly down-regulated RNAIII expression and subsequently inhibited hla transcription. In a co-culture of S. aureus and lung cells, topical isorhamnetin treatment protected against S. aureus-induced cell injury. Isorhamnetin may represent a leading compound for the development of anti-virulence drugs against S. aureus infections.

  7. Antioxidant alpha-lipoic acid inhibits osteoclast differentiation by reducing nuclear factor-kappaB DNA binding and prevents in vivo bone resorption induced by receptor activator of nuclear factor-kappaB ligand and tumor necrosis factor-alpha.

    Science.gov (United States)

    Kim, Hyon Jong; Chang, Eun-Ju; Kim, Hyun-Man; Lee, Seung Bok; Kim, Hyun-Duck; Su Kim, Ghi; Kim, Hong-Hee

    2006-05-01

    The relationship between oxidative stress and bone mineral density or osteoporosis has recently been reported. As bone loss occurring in osteoporosis and inflammatory diseases is primarily due to increases in osteoclast number, reactive oxygen species (ROS) may be relevant to osteoclast differentiation, which requires receptor activator of nuclear factor-kappaB ligand (RANKL). Tumor necrosis factor-alpha (TNF-alpha) frequently present in inflammatory conditions has a profound synergy with RANKL in osteoclastogenesis. In this study, we investigated the effects of alpha-lipoic acid (alpha-LA), a strong antioxidant clinically used for some time, on osteoclast differentiation and bone resorption. At concentrations showing no growth inhibition, alpha-LA potently suppressed osteoclastogenesis from bone marrow-derived precursor cells driven either by a high-dose RANKL alone or by a low-dose RANKL plus TNF-alpha (RANKL/TNF-alpha). alpha-LA abolished ROS elevation by RANKL or RANKL/TNF-alpha and inhibited NF-kappaB activation in osteoclast precursor cells. Specifically, alpha-LA reduced DNA binding of NF-kappaB but did not inhibit IKK activation. Furthermore, alpha-LA greatly suppressed in vivo bone loss induced by RANKL or TNF-alpha in a calvarial remodeling model. Therefore, our data provide evidence that ROS plays an important role in osteoclast differentiation through NF-kappaB regulation and the antioxidant alpha-lipoic acid has a therapeutic potential for bone erosive diseases.

  8. Supine posture inhibits cortical activity: Evidence from Delta and Alpha EEG bands.

    Science.gov (United States)

    Spironelli, Chiara; Busenello, Jessica; Angrilli, Alessandro

    2016-08-01

    Past studies have shown consistent evidence that body position significantly affects brain activity, revealing that both head-down and horizontal bed-rest are associated with cortical inhibition and altered perceptual and cognitive processing. The present study investigates the effects of body position on spontaneous, open-eyes, resting-state EEG cortical activity in 32 young women randomly assigned to one of two conditions, seated position (SP) or horizontal bed rest (BR). A between-group repeated-measure experimental design was used, EEG recordings were made from 38 scalp locations, and low-frequency (delta and alpha) amplitudes of the two groups were compared in four different conditions: when both groups (a) were seated (T0), (b) assumed two different body positions (seated vs. supine conditions, immediate [T1] and 120min later [T2]), and (c) were seated again (T3). Overall, the results showed no a priori between-group differences (T0) before experimental manipulation. As expected, delta amplitude, an index of cortical inhibition in awake resting participants, was significantly increased in group BR, revealing both rapid (T1) and mid-term (T2) inhibitory effects of supine or horizontal positions. Instead, the alpha band was highly sensitive to postural transitions, perhaps due to baroreceptor intervention and, unlike the delta band, underwent habituation and decreased after a 2-h bed rest. These results indicate clear-cut differences at rest between the seated and supine positions, thus supporting the view that the role of body position in the differences found between brain metabolic methods (fMRI and PET) in which participants lie horizontally, and EEG-MEG-TMS techniques with participants in a seated position, has been largely underestimated so far.

  9. The relaxing effect of perivascular tissue on porcine retinal arterioles in vitro is mimicked by N-methyl-D-aspartate and is blocked by prostaglandin synthesis inhibition

    DEFF Research Database (Denmark)

    Holmgaard, Kim; Aalkjaer, Christian; Lambert, John D C;

    2007-01-01

    PURPOSE: Retinal hyperperfusion resulting from disturbances in the regulation of arteriolar tone is involved in the pathophysiology of a variety of retinal diseases. The mechanisms underlying this regulation of tone involve cellular components in both the vascular wall and the perivascular tissue....... However, previous in vitro studies of the influence of perivascular retinal tissue on retinal tone regulation have been hampered by the release of an endogenous relaxing factor that renders the arteriole insensitive to vasoconstrictors. The purpose of the present study was to test whether N......-methyl-D-aspartate (NMDA) and gamma-amino butyric acid (GABA) receptors, and a cyclooxygenase (COX) product influence this effect of perivascular retinal tissue in vitro. METHODS: Porcine retinal arterioles were mounted in a wire myograph for isometric force measurements. The contractile effect of the prostaglandin...

  10. Prostaglandin E1 Combined with Alpha Lipoic Acid and Mecobalamin in Treating First Diagnosis of Type 2 Diabetes Peripheral Neuropathy%前列地尔联合α-硫辛酸及甲钴胺治疗初诊2型糖尿病周围神经病变疗效观察

    Institute of Scientific and Technical Information of China (English)

    杨昕; 刘志民

    2016-01-01

    Objective To observe the clinical efficacy of prostaglandin E1, alpha lipoic acid and mecobalamin on first diagnosis of type 2 diabetes peripheral neuropathy. Methods 350 patients with first diagnosis of type 2 diabetes peripheral neuropathy were selected and randomly divided into the prostaglandin E1+alpha lipoic acid+mecobalamin group 71 cases;prostaglandin E1+alpha lipoic acid group 69 cases; alpha lipoic acid+mecobalamin group 72 cases; prostaglandin E1+mecobalamin group 68 cases; control group 70 cases. The nerve conduction velocity , sensory symptoms and overall clinical efficacy were compared before and after treatment among the 5 groups. Results The nerve conduction velocity and the clinical symptoms of feeling in the 4 treatment groups improved compared with before treatment ( P < 0. 01 ); compared with the control group, the 4 treatment groups improved significantly better, the difference between groups was statistically significant ( P < 0. 01 ) , and the prostaglandin E1+alpha lipoic acid+mecobalamin group improved the most significantly. Conclusion On the basis of blood sugar control, comprehensive therapy of prostaglandin E1, alpha lipoic acid and mecobalamin is the key in treating and improving diabetic peripheral neuropathy.%目的:观察初诊2型糖尿病周围神经病变患者应用前列地尔、α-硫辛酸及甲钴胺的临床疗效。方法选取初诊2型糖尿病周围神经病变患者350例,随机分为前列地尔+α-硫辛酸+甲钴胺组71例,前列地尔+α-硫辛酸组69例,α-硫辛酸+甲钴胺组72例,前列地尔+甲钴胺组68例,对照组70例,比较5组患者治疗前后的神经传导速度及临床感觉症状和总体疗效。结果4个治疗组患者的神经传导速度及临床感觉症状均较治疗前有显著改善( P<0.01);与对照组相比,4个治疗组的改善程度显著优于对照组,组间差异有统计学意义( P<0.01),尤以前列地尔+α-硫辛酸

  11. Metabolism of prostaglandin E and of glutathione conjugate of prostaglandin A (GSH-prostaglandin A) by prostaglandin 9-ketoreductase from rabbit kidney

    DEFF Research Database (Denmark)

    Toft, B.S.; Hansen, Harald S.

    1979-01-01

    , which revealed that metabolism of prostaglandin E and GSH-prostaglandin A occurs by means of the same fractions. Furthermore, prostaglandin E and GSH-prostaglandin A are competitive inhibitors of the enzyme, when GSH-prostaglandin A and prostaglandin E are tested as substrates, respectively...

  12. Diacylglycerol pyrophosphate inhibits the alpha-amylase secretion stimulated by gibberellic acid in barley aleurone.

    Science.gov (United States)

    Racagni, Graciela; Villasuso, Ana L; Pasquaré, Susana J; Giusto, Norma M; Machado, Estela

    2008-11-01

    ABA plays an important regulatory role in seed germination because it inhibits the response to GA in aleurone, a secretory tissue surrounding the endosperm. Phosphatidic acid (PA) is a well-known intermediary in ABA signaling, but the role of diacylglycerol pyrophosphate (DGPP) in germination processes is not clearly established. In this study, we show that PA produced by phospholipase D (E.C. 3.1.4.4) during the antagonist effect of ABA in GA signaling is rapidly phosphorylated by phosphatidate kinase (PAK) to DGPP. This is a crucial fact for aleurone function because exogenously added dioleoyl-DGPP inhibits secretion of alpha-amylase (E.C. 3.2.1.1). Aleurone treatment with ABA and 1-butanol results in normal secretory activity, and this effect is reversed by addition of dioleoyl-DGPP. We also found that ABA decreased the activity of an Mg2+-independent, N-ethylmaleimide-insensitive form of phosphatidate phosphohydrolase (PAP2) (E.C. 3.1.3.4), leading to reduction of PA dephosphorylation and increased PAK activity. Sequence analysis using Arabidopsis thaliana lipid phosphate phosphatase (LPP) sequences as queries identified two putative molecular homologues, termed HvLPP1 and HvLPP2, encoding putative Lpps with the presence of well-conserved structural Lpp domains. Our results are consistent with a role of DGPP as a regulator of ABA antagonist effect in GA signaling and provide evidence about regulation of PA level by a PAP2 during ABA response in aleurone.

  13. A Computational Model of Inhibition of HIV-1 by Interferon-Alpha.

    Directory of Open Access Journals (Sweden)

    Edward P Browne

    Full Text Available Type 1 interferons such as interferon-alpha (IFNα inhibit replication of Human immunodeficiency virus (HIV-1 by upregulating the expression of genes that interfere with specific steps in the viral life cycle. This pathway thus represents a potential target for immune-based therapies that can alter the dynamics of host-virus interactions to benefit the host. To obtain a deeper mechanistic understanding of how IFNα impacts spreading HIV-1 infection, we modeled the interaction of HIV-1 with CD4 T cells and IFNα as a dynamical system. This model was then tested using experimental data from a cell culture model of spreading HIV-1 infection. We found that a model in which IFNα induces reversible cellular states that block both early and late stages of HIV-1 infection, combined with a saturating rate of conversion to these states, was able to successfully fit the experimental dataset. Sensitivity analysis showed that the potency of inhibition by IFNα was particularly dependent on specific network parameters and rate constants. This model will be useful for designing new therapies targeting the IFNα network in HIV-1-infected individuals, as well as potentially serving as a template for understanding the interaction of IFNα with other viruses.

  14. A Computational Model of Inhibition of HIV-1 by Interferon-Alpha.

    Science.gov (United States)

    Browne, Edward P; Letham, Benjamin; Rudin, Cynthia

    2016-01-01

    Type 1 interferons such as interferon-alpha (IFNα) inhibit replication of Human immunodeficiency virus (HIV-1) by upregulating the expression of genes that interfere with specific steps in the viral life cycle. This pathway thus represents a potential target for immune-based therapies that can alter the dynamics of host-virus interactions to benefit the host. To obtain a deeper mechanistic understanding of how IFNα impacts spreading HIV-1 infection, we modeled the interaction of HIV-1 with CD4 T cells and IFNα as a dynamical system. This model was then tested using experimental data from a cell culture model of spreading HIV-1 infection. We found that a model in which IFNα induces reversible cellular states that block both early and late stages of HIV-1 infection, combined with a saturating rate of conversion to these states, was able to successfully fit the experimental dataset. Sensitivity analysis showed that the potency of inhibition by IFNα was particularly dependent on specific network parameters and rate constants. This model will be useful for designing new therapies targeting the IFNα network in HIV-1-infected individuals, as well as potentially serving as a template for understanding the interaction of IFNα with other viruses.

  15. Fibroblast growth factor 7 inhibits cholesterol 7{alpha}-hydroxylase gene expression in hepatocytes

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Zhichao [Department of Biochemistry and Molecular Biology, Shanghai Medical College, Fudan University, Shanghai (China); Yu, Xuemei [Department of Endocrinology, Fengxian Central Hospital, Shanghai (China); Wu, Weibin; Jia, Dongwei; Chen, Yinle; Ji, Lingling; Liu, Xijun; Peng, Xiaomin [Department of Biochemistry and Molecular Biology, Shanghai Medical College, Fudan University, Shanghai (China); Li, Yintao [Institute of Endocrinology and Diabetology, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai (China); Yang, Lili [Department of Endocrinology, Fengxian Central Hospital, Shanghai (China); Ruan, Yuanyuan; Gu, Jianxin [Department of Biochemistry and Molecular Biology, Shanghai Medical College, Fudan University, Shanghai (China); Ren, Shifang, E-mail: renshifang@fudan.edu.cn [Department of Biochemistry and Molecular Biology, Shanghai Medical College, Fudan University, Shanghai (China); Zhang, Songwen, E-mail: songwenzhang@fudan.edu.cn [Department of Biochemistry and Molecular Biology, Shanghai Medical College, Fudan University, Shanghai (China)

    2012-07-13

    Highlights: Black-Right-Pointing-Pointer FGF7 strongly and rapidly down-regulates the expression of CYP7A1 in hepatocytes. Black-Right-Pointing-Pointer FGF7 suppresses the expression of CYP7A1 via FGFR2 and downstream JNK activation. Black-Right-Pointing-Pointer Blocking FGF7 abrogates HSC-induced inhibition of CYP7A1 expression in hepatocytes. -- Abstract: Cholesterol 7{alpha}-hydroxylase (CYP7A1) is the initial and rate-limiting enzyme for bile acid synthesis. Transcription of the CYP7A1 gene is regulated by bile acids, nuclear receptors and cytokines. Fibroblast growth factor 7 (FGF7) secreted from activated hepatic stellate cells (HSC) during chronic liver fibrosis regulates hepatocyte survival and liver regeneration. In the carbon tetrachloride (CCl{sub 4})-induced fibrotic mouse liver, we demonstrated that the expression of CYP7A1 was largely decreased while the expression of FGF7 was significantly increased. We further demonstrated that FGF7 inhibited CYP7A1 gene expression in hepatocytes. Knockdown study by short interfering RNA, kinase inhibition and phosphorylation assays revealed that the suppression of CYP7A1 expression by FGF7 was mediated by FGFR2 and its downstream JNK signaling cascade. The FGF7 neutralizing antibody restored CYP7A1 expression in Hep3B cells treated with conditioned medium from HSC. In summary, the data suggest that FGF7 is a novel regulator of CYP7A1 expression in hepatocytes and may prevent hepatocytes from accumulating toxic bile acids during liver injury and fibrosis.

  16. Carbonyl cyanide p-trifluoromethoxyphenylhydrazone (FCCP) induces initiation factor 2 alpha phosphorylation and translation inhibition in PC12 cells.

    Science.gov (United States)

    Muñoz, F; Martín, M E; Salinas, M; Fando, J L

    2001-03-09

    We have investigated the effect of the mitochondrial uncoupler carbonyl cyanide p-trifluoromethoxyphenylhydrazone (FCCP) on protein synthesis rate and initiation factor 2 (eIF2) phosphorylation in PC12 cells differentiated with nerve growth factor. FCCP treatment induced a very rapid 2-fold increase in intracellular Ca(2+) concentration that was accompanied by a strong protein synthesis rate inhibition (68%). The translation inhibition correlated with an increased phosphorylation of the alpha subunit of eIF2 (eIF2 alpha) (25% vs. 7%, for FCCP-treated and control cells, respectively) and a 1.7-fold increase in the double-stranded RNA-dependent protein kinase activity. No changes in the PKR endoplasmic reticulum-related kinase or eIF2 alpha phosphatase were found. Translational regulation may play a significant role in the process triggered by mitochondrial calcium mobilization.

  17. Inhibition of Lassa virus glycoprotein cleavage and multicycle replication by site 1 protease-adapted alpha(1-antitrypsin variants.

    Directory of Open Access Journals (Sweden)

    Anna Maisa

    Full Text Available BACKGROUND: Proteolytic processing of the Lassa virus envelope glycoprotein precursor GP-C by the host proprotein convertase site 1 protease (S1P is a prerequisite for the incorporation of the subunits GP-1 and GP-2 into viral particles and, hence, essential for infectivity and virus spread. Therefore, we tested in this study the concept of using S1P as a target to block efficient virus replication. METHODOLOGY/PRINCIPAL FINDING: We demonstrate that stable cell lines inducibly expressing S1P-adapted alpha(1-antitrypsin variants inhibit the proteolytic maturation of GP-C. Introduction of the S1P recognition motifs RRIL and RRLL into the reactive center loop of alpha(1-antitrypsin resulted in abrogation of GP-C processing by endogenous S1P to a similar level observed in S1P-deficient cells. Moreover, S1P-specific alpha(1-antitrypsins significantly inhibited replication and spread of a replication-competent recombinant vesicular stomatitis virus expressing the Lassa virus glycoprotein GP as well as authentic Lassa virus. Inhibition of viral replication correlated with the ability of the different alpha(1-antitrypsin variants to inhibit the processing of the Lassa virus glycoprotein precursor. CONCLUSIONS/SIGNIFICANCE: Our data suggest that glycoprotein cleavage by S1P is a promising target for the development of novel anti-arenaviral strategies.

  18. Use of vaginal prostaglandin gel before induction of labour.

    Science.gov (United States)

    Murphy, A J; Jalland, M; Pepperell, R J; Quinn, M A

    1980-05-01

    Tylose gel containing either 1.5 mg, 3.0 mg or 10.0 mg of prostaglandin F2 alpha was inserted into the posterior vaginal fornix of 165 patients on the evening before induction of labour. A control group of 100 patients received the gel alone. There was a significant reduction in the induction-delivery interval in nulliparae receiving at least 3.0 mg of prostaglandin, whereas, in multiparae all doses achieved this effect. There was also a significant reduction in the incidence of forceps delivery in nulliparae who received 3.0 mg or more of the prostaglandin gel; however, there was no difference in the incidence of spontneous labour, epidural anaesthesia or Caesarean section between the patients who received prostaglandin or those receiving gel alone.

  19. The role of prostaglandines in peristalsis of the human colon.

    Science.gov (United States)

    Bruch, H P; Schmidt, E; Laven, R; Kehrer, G; Wasner, K H

    1978-08-01

    Prostaglandines (PG) of the E and F series cause peristaltic activity in isolated longitudinal muscle strips of the human colon. As this phasic motor reaction can be varied by acetyl choline and adrenaline it was supposed, that prostaglandines contribute to peristalsis. The role of PG E and F in the human colon was studied by inhibiting the prostaglandine synthesis and by antagonizing the prostaglandine-effects. Indomethacin proved to be a suitable inhibitor. HR 546 was found a powerful antagonist. The effect of Pentagastrin and Cholecystokinin (CCK) on peristaltic activity were suppressed by Indomethacin and HR 546. The inhibition of peristalsis by Indomethacin and HR 546 was removed by high doses of PG E and F. On the basis of these results the role of PG for the motility of the gut is discussed.

  20. Alpha-amylase and alpha-glucosidase inhibition is differentially modulated by fucoidan obtained from Fucus vesiculosus and Ascophyllum nodosum.

    Science.gov (United States)

    Kim, Kyung-Tae; Rioux, Laurie-Eve; Turgeon, Sylvie L

    2014-02-01

    Fucoidan is a water-soluble, negatively charged, biologically active polysaccharide found in great abundance in brown marine algae. However, the inhibition of α-amylase and α-glucosidase by fucoidan derived from two algal species (Ascophyllum nodosum and Fucus vesiculosus) harvested at different periods (accounting for seasonal and yearly variations) has never been investigated. It was found that fucoidans inhibited α-glucosidase differently, depending on the algal species from which it was extracted and the algae's season of harvest. Fucoidan extracted from A. nodosum was a more potent inhibitor of α-glucosidase, with an IC50 ranging from 0.013 to 0.047 mg/mL, than the inhibition by fucoidan extracted from F. vesiculosus (IC50=0.049 mg/mL). In contrast, fucoidan extracted from F. vesiculosus did not inhibit α-amylase activity, while fucoidan from A. nodosum decreased α-amylase activity by 7-100% at 5 mg/mL depending upon the algae harvest period. An IC50 of 0.12-4.64 mg/mL for fucoidan from A. nodosum was found for the α-amylase inhibition. The ability of fucoidan to inhibit α-amylase and α-glucosidase thus varies according to the algae species and harvest period. A. nodosum is more suitable than F. vesiculosus as a source of fucoidan to inhibit α-amylase and α-glucosidase activities. Their potential benefits towards Type 2 diabetes management should be further investigated.

  1. alpha-Linolenic acid protects renal cells against palmitic acid lipotoxicity via inhibition of endoplasmic reticulum stress.

    Science.gov (United States)

    Katsoulieris, Elias; Mabley, Jon G; Samai, Mohamed; Green, Irene C; Chatterjee, Prabal K

    2009-11-25

    Unsaturated fatty acids may counteract the lipotoxicity associated with saturated fatty acids. Palmitic acid induced endoplasmic reticulum (ER) stress and caused apoptotic and necrotic cell death in the renal proximal tubular cell line, NRK-52E. We investigated whether alpha-linolenic acid, an unsaturated fatty acid, protected against ER stress and cell death induced by palmitic acid or by other non-nutrient ER stress generators. Incubation of NRK-52E cells for 24h with palmitic acid produced a significant increase in apoptosis and necrosis. Palmitic acid also increased levels of three indicators of ER stress - the phosphorylated form of the eukaryotic initiation factor 2alpha (eIF2alpha), C/EBP homologous protein (CHOP), and glucose regulated protein 78 (GRP78). alpha-Linolenic acid dramatically reduced cell death and levels of all three indicators of ER stress brought about by palmitic acid. Tunicamycin, which induces ER stress by glycosylation of proteins, produced similar effects to those obtained using palmitic acid; its effects were partially reversed by alpha-linolenic acid. Salubrinal (a phosphatase inhibitor) causes increased levels of the phosphorylated form of eIF2alpha - this effect was partially reversed by alpha-linolenic acid. Palmitoleate, a monosaturated fatty acid, had similar effects to those of alpha-linolenic acid. These results suggest that part of the mechanism of protection of the kidney by unsaturated fatty acids is through inhibition of ER stress, eIF2alpha phosphorylation and consequential reduction of CHOP protein expression and apoptotic renal cell death.

  2. NBBA, a synthetic small molecule, inhibits TNF-{alpha}-induced angiogenesis by suppressing the NF-{kappa}B signaling pathway

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Nam Hee; Jung, Hye Jin [Chemical Genomics Laboratory, Department of Biotechnology, Translational Research Center for Protein Function Control, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749 (Korea, Republic of); Shibasaki, Futoshi [Translation Research Project, Tokyo Metropolitan Institute of Medical Science, Tokyo 156-8506 (Japan); Kwon, Ho Jeong, E-mail: kwonhj@yonsei.ac.kr [Chemical Genomics Laboratory, Department of Biotechnology, Translational Research Center for Protein Function Control, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749 (Korea, Republic of)

    2010-01-15

    Nuclear factor-{kappa}B (NF-{kappa}B) is a crucial transcription factor that contributes to cancer development by regulating a number of genes involved in angiogenesis and tumorigenesis. Here, we describe (Z)-N-(3-(7-nitro-3-oxobenzo[d][1,2]selenazol-2(3H)-yl)benzylidene) propan-2-amine oxide (NBBA) as a new anti-angiogenic small molecule that targets NF-{kappa}B activity. NBBA showed stronger growth inhibition on human umbilical vein endothelial cells (HUVECs) than on the cancer cell lines we tested. Moreover, NBBA inhibited tumor necrosis factor-alpha (TNF-{alpha})-induced tube formation and invasion of HUVECs. In addition, NBBA suppressed the neovascularization of chorioallantonic membrane from growing chick embryos in vivo. To address the mode of action of the compound, the effect of NBBA on TNF-{alpha}-induced NF-{kappa}B transcription activity was investigated. NBBA suppressed TNF-{alpha}-induced c-Jun N-terminal kinase phosphorylation, which resulted in suppression of transcription of NF-{kappa}B and its target genes, including interleukin-8, interleukin-1{alpha}, and epidermal growth factor. Collectively, these results demonstrated that NBBA is a new anti-angiogenic small molecule that targets the NF-{kappa}B signaling pathway.

  3. PGC-1alpha inhibits oleic acid induced proliferation and migration of rat vascular smooth muscle cells.

    Directory of Open Access Journals (Sweden)

    Yan Zhang

    Full Text Available BACKGROUND: Oleic acid (OA stimulates vascular smooth muscle cell (VSMC proliferation and migration. The precise mechanism is still unclear. We sought to investigate the effects of peroxisome proliferator-activated receptor gamma (PPARgamma coactivator-1 alpha (PGC-1alpha on OA-induced VSMC proliferation and migration. PRINCIPAL FINDINGS: Oleate and palmitate, the most abundant monounsaturated fatty acid and saturated fatty acid in plasma, respectively, differently affect the mRNA and protein levels of PGC-1alpha in VSMCs. OA treatment resulted in a reduction of PGC-1alpha expression, which may be responsible for the increase in VSMC proliferation and migration caused by this fatty acid. In fact, overexpression of PGC-1alpha prevented OA-induced VSMC proliferation and migration while suppression of PGC-1alpha by siRNA enhanced the effects of OA. In contrast, palmitic acid (PA treatment led to opposite effects. This saturated fatty acid induced PGC-1alpha expression and prevented OA-induced VSMC proliferation and migration. Mechanistic study demonstrated that the effects of PGC-1alpha on VSMC proliferation and migration result from its capacity to prevent ERK phosphorylation. CONCLUSIONS: OA and PA regulate PGC-1alpha expression in VSMCs differentially. OA stimulates VSMC proliferation and migration via suppression of PGC-1alpha expression while PA reverses the effects of OA by inducing PGC-1alpha expression. Upregulation of PGC-1alpha in VSMCs provides a potential novel strategy in preventing atherosclerosis.

  4. 5'-nitro-indirubinoxime inhibits inflammatory response in TNF-alpha stimulated human umbilical vein endothelial cells.

    Science.gov (United States)

    Kim, Eun-Jung; Park, Won-Hwan; Ahn, Sang-Gun; Yoon, Jung-Hoon; Kim, Si-Wouk; Kim, Soo-A

    2010-07-01

    Inflammation plays a critical role in the development of atherosclerosis and TNF-alpha, a major inflammatory cytokine, induces inflammatory responses by enhancing the expression of adhesion molecules and the secretion of inflammatory mediators. Indirubin is an active compound of Polygonum tinctorium Lour (P. tinctorium) that has the ability to suppress inflammation. Previously, we described the novel indirubin derivative, 5'-nitro-indirubinoxime (5'-NIO), and demonstrated that it has potent anti-proliferative activity against various human cancer cells. In this study, we examined the effect of 5'-NIO on the TNF-alpha induced inflammatory conditions of human umbilical vein endothelial cells (HUVECs). We found that 5'-NIO inhibited TNF-alpha induced MCP-1 and IL-8 expression at the RNA and protein levels in HUVECs. Specifically, 5'-NIO significantly inhibited the TNF-alpha stimulated release of MCP-1 and IL-8, with levels that were only 19.8% and 30.9% of those of untreated control cells, respectively. Furthermore, 5'-NIO largely inhibited the adhesion of U937 cells to HUVECs by decreasing the expression level of ICAM-1 and VCAM-1. Overall, these observations suggest that 5'-NIO has the potential for use as an anti-atherosclerotic agent.

  5. Alpha-Amylase Inhibition and Antioxidative Capacity of Some Antidiabetic Plants Used by the Traditional Healers in Southeastern Nigeria

    Science.gov (United States)

    Oyedemi, Blessing O.; Ijeh, Ifeoma I.; Ohanyerem, Princemartins E.; Aiyegoro, Olayinka A.

    2017-01-01

    Oxidative stress plays a significant role in the pathogenesis of metabolic syndrome including diabetes mellitus (DM). The inhibition of alpha-amylase is an important therapeutic target in the regulation of postprandial increase of blood glucose in diabetic patients. The present study investigated the alpha-amylase inhibitory and antioxidant potential of selected herbal drugs used in the treatment of DM by the traditional healers in Isiala Mbano and Ikwuano regions of southeastern Nigeria. Antioxidant activity was evaluated in terms of free radical scavenging, reducing power, and total phenolic (TPC) and flavonoid content (TFC) in consonance with the TLC profiling. The results showed that methanol crude extracts from Anacardium occidentale (AO) and Ceiba pentandra (CP) recorded higher TPC and TFC, potent free radical scavenging, and efficient reducing power (RP) as compared with other plant samples. All the plant extracts exhibited a relative alpha-amylase inhibition apart from Strophanthus hispidus (SH) extract with a negative effect. We discovered a mild to weak correlation between alpha-amylase inhibition or antioxidative capacity and the total phenol or flavonoid content. At least in part, the results obtained in this work support the traditional use of certain plant species in the treatment of patients with DM.

  6. Structural Insights into Inhibition of Sterol 14[alpha]-Demethylase in the Human Pathogen Trypanosoma cruzi

    Energy Technology Data Exchange (ETDEWEB)

    Lepesheva, Galina I.; Hargrove, Tatiana Y.; Anderson, Spencer; Kleshchenko, Yuliya; Furtak, Vyacheslav; Wawrzak, Zdzislaw; Villalta, Fernando; Waterman, Michael R. (Vanderbilt); (NWU); (Meharry)

    2010-09-02

    Trypanosoma cruzi causes Chagas disease (American trypanosomiasis), which threatens the lives of millions of people and remains incurable in its chronic stage. The antifungal drug posaconazole that blocks sterol biosynthesis in the parasite is the only compound entering clinical trials for the chronic form of this infection. Crystal structures of the drug target enzyme, Trypanosoma cruzi sterol 14{alpha}-demethylase (CYP51), complexed with posaconazole, another antifungal agent fluconazole and an experimental inhibitor, (R)-4{prime}-chloro-N-(1-(2,4-dichlorophenyl)-2-(1H-imid-azol-1-yl)ethyl)biphenyl-4-carboxamide (VNF), allow prediction of important chemical features that enhance the drug potencies. Combined with comparative analysis of inhibitor binding parameters, influence on the catalytic activity of the trypanosomal enzyme and its human counterpart, and their cellular effects at different stages of the Trypanosoma cruzi life cycle, the structural data provide a molecular background to CYP51 inhibition and azole resistance and enlighten the path for directed design of new, more potent and selective drugs to develop an efficient treatment for Chagas disease.

  7. 15-Deoxy-delta(12,14)-prostaglandin J(2) inhibits IL-1beta-induced IKK enzymatic activity and IkappaBalpha degradation in rat chondrocytes through a PPARgamma-independent pathway.

    Science.gov (United States)

    Boyault, Sandrine; Bianchi, Arnaud; Moulin, David; Morin, Sylvie; Francois, Mathias; Netter, Patrick; Terlain, Bernard; Bordji, Karim

    2004-08-13

    Peroxisome proliferator-activated receptor gamma (PPARgamma) ligands have been shown to inhibit the effects of proinflammatory cytokines such as interleukin-1beta (IL-1beta). This cytokine plays a key role in articular pathophysiologies by inducing the production of inflammatory mediators such as nitric oxide (NO) and prostaglandin E(2) (PGE(2)). We previously demonstrated that 15d-PGJ(2) was more potent than troglitazone to counteract IL-1beta effects on chondrocytes. Here, we studied the action of 15d-PGJ(2) on intracellular targets in nuclear factor-kappaB (NF-kappaB) signalling pathway in IL-1beta treated rat chondrocytes. We found that 15d-PGJ(2) decreased inhibitor kappaBalpha (IkappaBalpha) degradation but not its phosphorylation by specifically inhibiting IkappaB kinase beta (IKKbeta), but not IKKalpha, enzymatic activity. We further evaluated the involvement of PPARgamma in the anti-inflammatory action of its ligands. In chondrocytes overexpressing functional PPARgamma protein, 15d-PGJ(2) pre-treatment inhibited inducible NO synthase and COX-2 mRNA expression, nitrite and PGE(2) production, p65 translocation and NF-kappaB activation. Troglitazone or rosiglitazone pre-treatment had no effect. 15d-PGJ(2) exhibited the same effect in chondrocytes overexpressing mutated PPARgamma protein. These results suggest that 15d-PGJ(2) exerts its anti-inflammatory effect in rat chondrocytes by a PPARgamma-independent mechanism, which can be conferred to a partial inhibition of IkappaBalpha degradation.

  8. DL-alpha-difluoromethyl[3,4-3H]arginine metabolism in tobacco and mammalian cells. Inhibition of ornithine decarboxylase activity after arginase-mediated hydrolysis of DL-alpha-difluoromethylarginine to DL-alpha-difluoromethylornithine.

    Science.gov (United States)

    Slocum, R D; Bitonti, A J; McCann, P P; Feirer, R P

    1988-10-01

    DL-alpha-Difluoromethylarginine (DFMA) is an enzyme-activated irreversible inhibitor of arginine decarboxylase (ADC) in vitro. DFMA has also been shown to inhibit ADC activities in a variety of plants and bacteria in vivo. However, we questioned the specificity of this inhibitor for ADC in tobacco ovary tissues, since ornithine decarboxylase (ODC) activity was strongly inhibited as well. We now show that [3,4-3H]DFMA is metabolized to DL-alpha-difluoromethyl[3,4-3H]ornithine [( 3,4-3H]DFMO), the analogous mechanism-based inhibitor of ODC, by tobacco tissues in vivo. Both tobacco and mammalian (mouse, bovine) arginases (EC 3.5.3.1) hydrolyse DFMA to DFMO in vitro, suggesting a role for this enzyme in mediating the indirect inhibition of ODC by DFMA in tobacco. These results suggest that DFMA may have other effects, in addition to the inhibition of ADC, in tissues containing high arginase activities. The recent development of potent agmatine-based ADC inhibitors should permit selective inhibition of ADC, rather than ODC, in such tissues, since agmatine is not a substrate for arginase.

  9. Prostaglandins, renin, aldosterone, and catecholamines in preeclampsia.

    Science.gov (United States)

    Pedersen, E B; Christensen, N J; Christensen, P; Johannesen, P; Kornerup, H J; Kristensen, S; Lauritsen, J G; Leyssac, P P; Rasmussen, A B; Wohlert, M

    1983-01-01

    Urinary excretion of prostaglandin E2 (PGE2) and F2 alpha (PGF2 alpha), plasma concentrations of renin (PRC), aldosterone (PAC), noradrenaline (PNA) and adrenaline (PA) were determined in the third trimester of pregnancy, 5 days and 3 months after delivery in preeclampsia and normotensive pregnant and non-pregnant control subjects. PGE2 was higher in pregnant control subjects than in non-pregnant subjects, but reduced to non-pregnant level in preeclampsia. PGF2 alpha was the same in preeclampsia and normotensive pregnancy but higher than in the non-pregnant group. PRC and PAC were increased during pregnancy, but considerably lesser in preeclampsia than during normotensive pregnancy. PNA and PA were the same in all three groups. All parameters were normal 3 months after delivery. There were no correlations between any of the hormones and blood pressure in any of the groups. PGE2 was positively correlated to PRC. The lack of renal PGE2 in preeclampsia might be responsible for the decrease in renal blood flow and sodium excretion, and the changes in PRC and PAC are supposed to be secondary to changes in PGE2. It is hypothesised that preeclampsia is a state of prostaglandin deficiency.

  10. TNF-alpha blockade by a dimeric TNF type I receptor molecule selectively inhibits adaptive immune responses.

    Science.gov (United States)

    Colagiovanni, D B; Suniga, M A; Frazier, J L; Edwards, C K; Fleshner, M; McCay, J A; White, K L; Shopp, G M

    2000-11-01

    Tumor necrosis factor-alpha (TNF-alpha) is a mediator of severe inflammatory processes, including rheumatoid arthritis. Suppression of TNF with a soluble type I or type II receptor molecule (TNF-RI or TNF-RII) has the potential to decrease cytokine levels and modulate inflammatory diseases in humans. However, it has recently been reported that treatment of mice with a TNF-RI:Fc immunoadhesin protein augmented Gram positive infections and subsequent mortality. To determine if TNF-alpha blockade with soluble TNF-alpha receptors might alter immune system function, assays were assessed in rodents treated with a dimeric form of the p55 TNF-RI, Tumor Necrosis Factor-binding protein (TNFbp). Administration of TNFbp resulted in suppression of primary and secondary IgG antibody responses and cell-mediated immune function. No treatment-related differences were detected in immune-enhancing assays or non-specific immune function parameters. Bacterial host resistance assays with Listeria monocytogenes, Staphylococcus aureus or Escherichia coli showed an increase in tissue colony counts only with L. monocytogenes challenged animals following TNFbp administration. These results suggest that TNFbp has the capacity to inhibit adaptive immune function in experimental animal models. Studies suggest that while reducing TNF-alpha is important in controlling cytokine-dependent disease states, maintenance of a threshold level may be critical for normal immune function.

  11. Human cytomegalovirus infection inhibits tumor necrosis factor alpha (TNF-alpha) signaling by targeting the 55-kilodalton TNF-alpha receptor.

    Science.gov (United States)

    Baillie, J; Sahlender, D A; Sinclair, J H

    2003-06-01

    Infection with human cytomegalovirus (HCMV) results in complex interactions between viral and cellular factors which perturb many cellular functions. HCMV is known to target the cell cycle, cellular transcription, and immunoregulation, and it is believed that this optimizes the cellular environment for viral DNA replication during productive infection or during carriage in the latently infected host. Here, we show that HCMV infection also prevents external signaling to the cell by disrupting the function of TNFRI, the 55-kDa receptor for tumor necrosis factor alpha (TNF-alpha), one of the receptors for a potent cytokine involved in eliciting a wide spectrum of cellular responses, including antiviral responses. HCMV infection of fully permissive differentiated monocytic cell lines and U373 cells resulted in a reduction in cell surface expression of TNFRI. The reduction appeared to be due to relocalization of TNFRI from the cell surface and was reflected in the elimination of TNF-alpha-induced Jun kinase activity. Analysis of specific phases of infection suggested that viral early gene products were responsible for this relocalization. However, a mutant HCMV in which all viral gene products known to be involved in down-regulation of major histocompatibility complex (MHC) class I were deleted still resulted in relocalization of TNFRI. Consequently, TNFRI relocalization by HCMV appears to be mediated by a novel viral early function not involved in down-regulation of cell surface MHC class I expression. We suggest that upon infection, HCMV isolates the cell from host-mediated signals, forcing the cell to respond only to virus-specific signals which optimize the cell for virus production and effect proviral responses from bystander cells.

  12. Cafestol, a coffee-specific diterpene, is a novel extracellular signal-regulated kinase inhibitor with AP-1-targeted inhibition of prostaglandin E2 production in lipopolysaccharide-activated macrophages.

    Science.gov (United States)

    Shen, Ting; Lee, Jaehwi; Lee, Eunji; Kim, Seong Hwan; Kim, Tae Woong; Cho, Jae Youl

    2010-01-01

    Coffee is a popular beverage worldwide with various nutritional benefits. Diterpene cafestol, one of the major components of coffee, contributes to its beneficial effects through various biological activities such as chemopreventive, antitumorigenic, hepatoprotective, antioxidative and antiinflammatory effects. In this study, we examined the precise molecular mechanism of the antiinflammatory activity of cafestol in terms of prostaglandin E(2) (PGE(2)) production, a critical factor involved in inflammatory responses. Cafestol inhibited both PGE(2) production and the mRNA expression of cyclooxygenase (COX)-2 from lipopolysaccharide (LPS)-treated RAW264.7 cells. Interestingly, this compound strongly decreased the translocation of c-Jun into the nucleus and AP-1 mediated luciferase activity. In kinase assays using purified extracellular signal-regulated kinase 2 (ERK2) or immunoprecipitated ERK prepared from LPS-treated cells in the presence or absence of cafestol, it was found that this compound can act as an inhibitor of ERK2 but not of ERK1 and mitogen-activated protein kinase kinase 1 (MEK 1). Therefore our data suggest that cafestol may be a novel ERK inhibitor with AP-1-targeted inhibitory activity against PGE(2) production in LPS-activated RAW264.7 cells.

  13. Corrosion inhibition of mild steel in 1 M HCl solution by henna extract: A comparative study of the inhibition by henna and its constituents (Lawsone, Gallic acid, {alpha}-D-Glucose and Tannic acid)

    Energy Technology Data Exchange (ETDEWEB)

    Ostovari, A. [Technical Inspection Engineering Department, Petroleum University of Technology, Abadan (Iran, Islamic Republic of)], E-mail: A.Ostovari@gmail.com; Hoseinieh, S.M.; Peikari, M. [Technical Inspection Engineering Department, Petroleum University of Technology, Abadan (Iran, Islamic Republic of); Shadizadeh, S.R. [Petroleum Engineering Department, Petroleum University of Technology, Abadan (Iran, Islamic Republic of); Hashemi, S.J. [Technical Inspection Engineering Department, Petroleum University of Technology, Abadan (Iran, Islamic Republic of)

    2009-09-15

    The inhibitive action of henna extract (Lawsonia inermis) and its main constituents (lawsone, gallic acid, {alpha}-D-Glucose and tannic acid) on corrosion of mild steel in 1 M HCl solution was investigated through electrochemical techniques and surface analysis (SEM/EDS). Polarization measurements indicate that all the examined compounds act as a mixed inhibitor and inhibition efficiency increases with inhibitor concentration. Maximum inhibition efficiency (92.06%) is obtained at 1.2 g/l henna extract. Inhibition efficiency increases in the order: lawsone > henna extract > gallic acid > {alpha}-D-Glucose > tannic acid. Also, inhibition mechanism and thermodynamic parameters are discussed.

  14. The bitter barricading of prostaglandin biosynthesis pathway: understanding the molecular mechanism of selective cyclooxygenase-2 inhibition by amarogentin, a secoiridoid glycoside from Swertia chirayita.

    Directory of Open Access Journals (Sweden)

    Shantanu Shukla

    Full Text Available Swertia chirayita, a medicinal herb inhabiting the challenging terrains and high altitudes of the Himalayas, is a rich source of essential phytochemical isolates. Amarogentin, a bitter secoiridoid glycoside from S. chirayita, shows varied activity in several patho-physiological conditions, predominantly in leishmaniasis and carcinogenesis. Experimental analysis has revealed that amarogentin downregulates the cyclooxygenase-2 (COX-2 activity and helps to curtail skin carcinogenesis in mouse models; however, there exists no account on selective inhibition of the inducible cyclooxygenase (COX isoform by amarogentin. Hence the computer-aided drug discovery methods were used to unravel the COX-2 inhibitory mechanism of amarogentin and to check its selectivity for the inducible isoform over the constitutive one. The generated theoretical models of both isoforms were subjected to molecular docking analysis with amarogentin and twenty-one other Food and Drug Authority (FDA approved lead molecules. The post-docking binding energy profile of amarogentin was comparable to the binding energy profiles of the FDA approved selective COX-2 inhibitors. Subsequent molecular dynamics simulation analysis delineated the difference in the stability of both complexes, with amarogentin-COX-2 complex being more stable after 40ns simulation. The total binding free energy calculated by MMGBSA for the amarogentin-COX-2 complex was -52.35 KCal/mol against a binding free energy of -8.57 KCal/mol for amarogentin-COX-1 complex, suggesting a possible selective inhibition of the COX-2 protein by the natural inhibitor. Amarogentin achieves this potential selectivity by small, yet significant, structural differences inherent to the binding cavities of the two isoforms. Hypothetically, it might block the entry of the natural substrates in the hydrophobic binding channel of the COX-2, inhibiting the cyclooxygenation step. To sum up briefly, this work highlights the mechanism of the

  15. Phentolamine inhibits exocytosis of glucagon by Gi2 protein-dependent activation of calcineurin in rat pancreatic alpha -cells.

    Science.gov (United States)

    Høy, M; Bokvist, K; Xiao-Gang, W; Hansen, J; Juhl, K; Berggren, P O; Buschard, K; Gromada, J

    2001-01-12

    Capacitance measurements were used to investigate the molecular mechanisms by which imidazoline compounds inhibit glucagon release in rat pancreatic alpha-cells. The imidazoline compound phentolamine reversibly decreased depolarization-evoked exocytosis >80% without affecting the whole-cell Ca(2+) current. During intracellular application through the recording pipette, phentolamine produced a concentration-dependent decrease in the rate of exocytosis (IC(50) = 9.7 microm). Another imidazoline compound, RX871024, exhibited similar effects on exocytosis (IC(50) = 13 microm). These actions were dependent on activation of pertussis toxin-sensitive G(i2) proteins but were not associated with stimulation of ATP-sensitive K(+) channels or adenylate cyclase activity. The inhibitory effect of phentolamine on exocytosis resulted from activation of the protein phosphatase calcineurin and was abolished by cyclosporin A and deltamethrin. Exocytosis was not affected by intracellular application of specific alpha(2), I(1), and I(2) ligands. Phentolamine reduced glucagon release (IC(50) = 1.2 microm) from intact islets by 40%, an effect abolished by pertussis toxin, cyclosporin A, and deltamethrin. These data suggest that imidazoline compounds inhibit glucagon secretion via G(i2)-dependent activation of calcineurin in the pancreatic alpha-cell. The imidazoline binding site is likely to be localized intracellularly and probably closely associated with the secretory granules.

  16. Inhibition of lipid synthesis and secretion in long-term cultures of adult rat hepatocytes by alpha-asarone.

    Science.gov (United States)

    Hernández, A; López, M L; Chamorro, G; Mendoza-Figueroa, T

    1993-04-01

    In this work we studied the effect of alpha-asarone, a hypolipidemic active principle of Guatteria gaumeri Greenman, on hepatic lipid metabolism using adult rat hepatocytes cultured on a feeder layer of 3T3 cells. These cultures synthesize and secrete for at least two weeks various lipids from [14C]-acetic and [14C]-oleic acid. Exposure for one or two weeks to 10 micrograms/ml of alpha-asarone decreased the secretion of various lipids to the culture medium; triacylglycerol secretion was inhibited by 80-97%, phospholipid secretion by 70-87%, cholesterol by 64-70%, and cholesterol esters by 50-92%. The incorporation of [14C]-acetic acid into cellular lipids decreased by 30-81% and that of [14C]-oleic acid into phospholipids by 25-47% whereas the incorporation of [14C]-oleic acid into triglycerides and cholesterol esters increased 3.2 fold and by 28-36%, respectively. Similarly, the activities of glycerol-3-phosphate dehydrogenase and malic enzyme, marker enzymes of glycerolipid and fatty acid synthesis, decreased by 22-50% and 30-76%, respectively. Our results show that the exposure of the 3T3-hepatocyte cultures to micromolar concentrations of alpha-asarone significantly inhibits lipid secretion and probably lipid synthesis. They also suggest that at least part of the hypolipidemic effect could be due to a decrease in the secretion of lipids (i.e., lipoproteins) by the hepatocytes.

  17. A synthetic peptide derived from A1 module in CRD4 of human TNF receptor-1 inhibits binding and proinflammatory effect of human TNF-alpha.

    Science.gov (United States)

    Cao, Yingnan; Wang, Zhaohe; Bu, Xianzhang; Tang, Shu; Mei, Zhengrong; Liu, Peiqing

    2009-06-01

    Tumour necrosis factor alpha (TNF-alpha) is a proinflammatory cytokine, which has been shown to be a causative factor in rheumatoid arthritis, inflammatory bowel disease and septic shock. Proinflammatory effect of TNF-alpha is activated mainly through human TNF receptor-1 (TNF-R1). However, the role of the fourth cystein-rich domain (CRD4) of TNF-R1 extracellular portion in the interaction of TNF-alpha with TNF-R1 is still unclear. In the present study, binding activity of TNF-alpha to TNF-R1 and protein levels of IkappaB-alpha and nuclear transcription factor kappa B (NF-kappaB) p65 subunit in HeLa cells were measured using enzyme-linked immunosorbent assay (ELISA) and western-blot analysis. Pep 3 (LRENECVS) which was derived from the hydrophilic region of A1 module in CRD4 remarkably inhibited the binding of TNF-alpha to TNF-R1, and also reversed TNF-alpha-induced degradation of IkappaB-alpha and nuclear translocation of NF-kappaB p65 subunit in HeLa cells. Our results confirmed that the hydrophilic region of A1 module in CRD4 participated in the interaction of TNF-alpha with TNF-R1, and demonstrated the potential of small-molecule TNF-alpha extracellular inhibitors targeting at A1 module in CRD4 of TNF-R1 in suppressing proinflammatory effect of TNF-alpha.

  18. An antisense oligodeoxynucleotide that depletes RI alpha subunit of cyclic AMP-dependent protein kinase induces growth inhibition in human cancer cells.

    Science.gov (United States)

    Yokozaki, H; Budillon, A; Tortora, G; Meissner, S; Beaucage, S L; Miki, K; Cho-Chung, Y S

    1993-02-15

    Enhanced expression of the RI alpha subunit of cyclic AMP-dependent protein kinase type I has been correlated with cancer cell growth. We provide evidence that RI alpha is a growth-inducing protein that may be essential for neoplastic cell growth. Human colon, breast, and gastric carcinoma and neuroblastoma cell lines exposed to a 21-mer human RI alpha antisense phosphorothioate oligodeoxynucleotide (S-oligodeoxynucleotide) exhibited growth inhibition with no sign of cytotoxicity. Mismatched sequence (random) S-oligodeoxynucleotides of the same length exhibited no effect. The growth inhibitory effect of RI alpha antisense oligomer correlated with a decrease in the RI alpha mRNA and protein levels and with an increase in RII beta (the regulatory subunit of protein kinase type II) expression. The growth inhibition was abolished, however, when cells were exposed simultaneously to both RI alpha and RII beta antisense S-oligodeoxynucleotides. The RII beta antisense S-oligodeoxynucleotide alone, exhibiting suppression of RII beta along with enhancement of RI alpha expression, led to slight stimulation of cell growth. These results demonstrate that two isoforms of cyclic AMP receptor proteins, RI alpha and RII beta, are reciprocally related in the growth control of cancer cells and that the RI alpha antisense oligodeoxynucleotide, which efficiently depletes the growth stimulatory RI alpha, is a powerful biological tool toward suppression of malignancy.

  19. Noscapine inhibits hypoxia-mediated HIF-1alpha expression andangiogenesis in vitro: a novel function for an old drug.

    Science.gov (United States)

    Newcomb, Elizabeth W; Lukyanov, Yevgeniy; Schnee, Tona; Ali, M Aktar; Lan, Li; Zagzag, David

    2006-05-01

    Overexpression of hypoxia-inducible factor-1 (HIF-1) is a common feature in solid malignancies related to oxygen deficiency. Since increased HIF-1 expression correlates with advanced disease stage, increased angiogenesis and poor prognosis, HIF-1 and its signaling pathway have become targets for cancer chemotherapy. In this study, we identified noscapine to be a novel small molecule inhibitor of the HIF-1 pathway based on its structure-function relation-ships with HIF-1 pathway inhibitors belonging to the benzylisoquinoline class of plant metabolites and/or to microtubule binding agents. We demonstrate that noscapine treatment of human glioma U87MG and T98G cell lines exposed to the hypoxic mimetic agent, CoCl2, inhibits hypoxia-mediated HIF-1alpha expression and transcriptional activity as measured by decreased secretion of VEGF, a HIF-1 target gene. Inhibition of hypoxia-mediated HIF-1alpha expression was due, in part, to its ability to inhibit accumulation of HIF-1alpha in the nucleus and target it for degradation via the proteasome. One mechanism of action of microtubule binding agents is their antiangiogenic activity associated with disruption of endothelial tubule formation. We show that noscapine has similar properties in vitro. Thus, noscapine may possess novel antiangiogenic activity associated with two broad mechanisms of action: first, by decreasing HIF-1alpha expression in hypoxic tumor cells, upregulation of target genes, such as VEGF, would be decreased concomitant with its associated angiogenic activity; second, by inhibiting endothelial cells from forming blood vessels in response to VEGF stimulation, it may limit the process of neo-vascularization, correlating with antitumor activity in vivo. For more than 75 years, noscapine has traditionally been used as an oral cough suppressant with no known toxic side effects in man. Thus, the studies reported here have found a novel function for an old drug. Given its low toxicity profile, its demonstrated

  20. Prostaglandin E2 regulates macrophage colony stimulating factor secretion by human bone marrow stromal cells.

    Science.gov (United States)

    Besse, A; Trimoreau, F; Faucher, J L; Praloran, V; Denizot, Y

    1999-07-08

    Bone marrow stromal cells regulate marrow haematopoiesis by secreting growth factors such as macrophage colony stimulating factor (M-CSF) that regulates the proliferation, differentiation and several functions of cells of the mononuclear-phagocytic lineage. By using a specific ELISA we found that their constitutive secretion of M-CSF is enhanced by tumour necrosis factor-alpha (TNF-alpha). The lipid mediator prostaglandin E2 (PGE2) markedly reduces in a time- and dose-dependent manner the constitutive and TNF-alpha-induced M-CSF synthesis by bone marrow stromal cells. In contrast, other lipid mediators such as 12-HETE, 15-HETE, leukotriene B4, leukotriene C4 and lipoxin A4 have no effect. EP2/EP4 selective agonists (11-deoxy PGE1 and 1-OH PGE1) and EP2 agonist (19-OH PGE2) inhibit M-CSF synthesis by bone marrow stromal cells while an EP1/EP3 agonist (sulprostone) has no effect. Stimulation with PGE2 induces an increase of intracellular cAMP levels in bone marrow stromal cells. cAMP elevating agents (forskolin and cholera toxin) mimic the PGE2-induced inhibition of M-CSF production. In conclusion, PGE2 is a potent regulator of M-CSF production by human bone marrow stromal cells, its effects being mediated via cAMP and PGE receptor EP2/EP4 subtypes.

  1. Prostaglandins and Rheumatoid Arthritis

    Directory of Open Access Journals (Sweden)

    Mohammad Javad Fattahi

    2012-01-01

    Full Text Available Rheumatoid arthritis (RA is a chronic, autoimmune, and complex inflammatory disease leading to bone and cartilage destruction, whose cause remains obscure. Accumulation of genetic susceptibility, environmental factors, and dysregulated immune responses are necessary for mounting this self-reacting disease. Inflamed joints are infiltrated by a heterogeneous population of cellular and soluble mediators of the immune system, such as T cells, B cells, macrophages, cytokines, and prostaglandins (PGs. Prostaglandins are lipid inflammatory mediators derived from the arachidonic acid by multienzymatic reactions. They both sustain homeostatic mechanisms and mediate pathogenic processes, including the inflammatory reaction. They play both beneficial and harmful roles during inflammation, according to their site of action and the etiology of the inflammatory response. With respect to the role of PGs in inflammation, they can be effective mediators in the pathophysiology of RA. Thus the use of agonists or antagonists of PG receptors may be considered as a new therapeutic protocol in RA. In this paper, we try to elucidate the role of PGs in the immunopathology of RA.

  2. The Endocannabinoid Metabolite Prostaglandin E2 (PGE2)-Glycerol Inhibits Human Neutrophil Functions: Involvement of Its Hydrolysis into PGE2 and EP Receptors.

    Science.gov (United States)

    Turcotte, Caroline; Zarini, Simona; Jean, Stéphanie; Martin, Cyril; Murphy, Robert C; Marsolais, David; Laviolette, Michel; Blanchet, Marie-Renée; Flamand, Nicolas

    2017-03-03

    The endocannabinoids 2-arachidonoyl-glycerol and N-arachidonoyl-ethanolamine mediate an array of pro- and anti-inflammatory effects. These effects are related, in part, to their metabolism by eicosanoid biosynthetic enzymes. For example, N-arachidonoyl-ethanolamine and 2-arachidonoyl-glycerol can be metabolized by cyclooxygenase-2 into PG-ethanolamide (PG-EA) and PG-glycerol (PG-G), respectively. Although PGE2 is a recognized suppressor of neutrophil functions, the impact of cyclooxygenase-derived endocannabinoids such as PGE2-EA or PGE2-G on neutrophils is unknown. This study's aim was to define the effects of these mediators on neutrophil functions and the underlying cellular mechanisms involved. We show that PGE2-G, but not PGE2-EA, inhibits leukotriene B4 biosynthesis, superoxide production, migration, and antimicrobial peptide release. The effects of PGE2-G were prevented by EP1/EP2 receptor antagonist AH-6809 but not the EP4 antagonist ONO-AE2-227. The effects of PGE2-G required its hydrolysis into PGE2, were not observed with the non-hydrolyzable PGE2-serinol amide, and were completely prevented by methyl-arachidonoyl-fluorophosphate and palmostatin B, and partially prevented by JZL184 and WWL113. Although we could detect six of the documented PG-G hydrolases in neutrophils by quantitative PCR, only ABHD12 and ABHD16A were detected by immunoblot. Our pharmacological data, combined with our protein expression data, did not allow us to pinpoint one PGE2-G lipase, and rather support the involvement of an uncharacterized lipase and/or of multiple hydrolases. In conclusion, we show that PGE2-G inhibits human neutrophil functions through its hydrolysis into PGE2, and by activating the EP2 receptor. This also indicates that neutrophils could regulate inflammation by altering the balance between PG-G and PG levels in vivo.

  3. JNK suppression is essential for 17β-Estradiol inhibits prostaglandin E2-Induced uPA and MMP-9 expressions and cell migration in human LoVo colon cancer cells

    Directory of Open Access Journals (Sweden)

    Chen Wei-Kung

    2011-08-01

    Full Text Available Abstract Background Epidemiological studies demonstrate that the incidence and mortality rates of colorectal cancer in women are lower than in men. However, it is unknown if 17β-estradiol treatment is sufficient to inhibit prostaglandin E2 (PGE2-induced cellular motility in human colon cancer cells. Methods We analyzed the protein expression of urokinase plasminogen activator (uPA, tissue plasminogen activator (tPA, matrix metallopeptidases (MMPs, plasminogen activator inhibitor-1 (PAI-1 and tissue inhibitor of metalloproteinases (TIMPs, and the cellular motility in PGE2-stimulated human LoVo cells. 17β-Estradiol and the inhibitors including LY294002 (Akt activation inhibitor, U0126 (ERK1/2 inhibitor, SB203580 (p38 MAPK inhibitor, SP600125 (JNK1/2 inhibitor, QNZ (NFκB inhibitor and ICI 182 780 were further used to explore the inhibitory effects of 17β-estradiol on PGE2-induced LoVo cell motility. Student's t-test was used to analyze the difference between the two groups. Results Upregulation of urokinase plasminogen activator (uPA, tissue plasminogen activator (tPA and matrix metallopeptidases (MMPs is reported to associate with the development of cancer cell mobility, metastasis, and subsequent malignant tumor. After administration of inhibitors including LY294002, U0126, SB203580, SP600125 or QNZ, we found that PGE2 treatment up-regulated uPA and MMP-9 expression via JNK1/2 signaling pathway, thus promoting cellular motility in human LoVo cancer cells. However, PGE2 treatment showed no effects on regulating expression of tPA, MMP-2, plasminogen activator inhibitor-1 (PAI-1, tissue inhibitor of metalloproteinase-1, -2, -3 and -4 (TIMP-1, -2, -3 and -4. We further observed that 17β-estradiol treatment inhibited PGE2-induced uPA, MMP-9 and cellular motility by suppressing activation of JNK1/2 in human LoVo cancer cells. Conclusions Collectively, these results suggest that 17β-estradiol treatment significantly inhibits PGE2-induced motility

  4. Inhibition by N'-nitrosonornicotine of the catalytic activity of glutamate dehydrogenase in alpha-ketoglutarate amination.

    Science.gov (United States)

    Mao, You-An; Zhong, Ke-Jun; Wei, Wan-Zhi; Wei, Xin-Liang; Lu, Hong-Bing

    2005-02-01

    The effect of N'-nitrosonornicotine (NNN), one of the tobacco-specific nitrosamines, on the catalytic activity of glutamate dehydrogenase (GLDH) in the alpha-ketoglutarate amination, using reduced nicotinamide adenine dinucleotide as coenzyme, was studied by a chronoamperometric method. The maximum reaction rate of the enzyme-catalyzed reaction and the Michaelis-Menten constant, or the apparent Michaelis-Menten constant, were determined in the absence and presence of NNN. NNN remarkably inhibited the bio-catalysis activity of GLDH, and was a reversible competitive inhibitior with K(i), estimated as 199 micromol l(-1) at 25 degrees C and pH 8.0.

  5. Evaluation of alpha- amylase inhibition by Urtica dioica and Juglans regia extracts

    Directory of Open Access Journals (Sweden)

    Mahsa Rahimzadeh

    2014-06-01

    Full Text Available Objective(s:One strategy for the treatment of diabetes is inhibition of pancreatic α- amylase. Plants contains different chemical constituents with potential for inhibition of α-amylase and hence maybe used as therapeutic. Materials and Methods: Urtica dioica and Juglans regia Linn were tested for α-amylase inhibition. Different concentrations of leaf aqueous extracts were incubated with enzyme substrate solution and the activity of enzyme was measured. For determination of the type of inhibition, Dixon plot was depicted. Acarbose was used as the standard inhibitor. Results: Both plant extracts showed time and concentration dependent inhibition of α-amylase. 60% inhibition was seen with 2 mg/ml of U. dioica and0.4 mg/ml of J. regia aqueous extract. Dixon plots revealed the type of α-amylase inhibition by these two extracts as competitive inhibition. Conclusion: Determination of the type of α-amylase inhibition by these plant extracts could provide by successful use of plant chemicals as drug targets.

  6. Effects of aspirin plus alpha-tocopherol on brain slices damage after hypoxia-reoxygenation in rats with type 1-like diabetes mellitus.

    Science.gov (United States)

    González-Correa, J A; Arrebola, M M; Cansino, A L; Muñoz-Marín, J; Guerrero, A; Sánchez de la Cuesta, F; De la Cruz, J P

    2006-06-12

    Diabetes mellitus is a risk factor for cerebrovascular ischemic disease. Aspirin (acetylsalicylic acid) is the most widely used drug for the secondary prevention of thrombotic phenomena. It has been also recently demonstrated that alpha-tocopherol influenced in vitro the antiplatelet effect of aspirin. The aim of the present study is to evaluate the effects aspirin plus alpha-tocopherol on cerebral oxidative stress, prostaglandin production and the nitric oxide pathway in a model of hypoxia-reoxygenation in rat brain slices. Our results show an imbalance in brain oxidative status (reflected mainly as the increase in lipid peroxides) as a result of diabetes itself rather than a failure of the glutathione-based antioxidant system. Moreover, our results also show a higher concentration of prostaglandins in the brain of diabetic animals and a higher nitric oxide concentration, mainly through a high iNOS activity. After 180 min of post-hypoxia reoxygenation, LDH activity was 40.6% higher in animals with diabetes, in comparison to non-diabetic animals. The increase of the LDH efflux observed in non-treated rats was reduced by 31.2% with aspirin, by 34.7% with alpha-tocopherol and by 69.8% with the association aspirin-alpha-tocopherol. The accumulation of prostaglandin E2 observed in diabetic non-treated rats was reduced statistically after the treatment with aspirin (34.2% inhibition), alpha-tocopherol (19.3% inhibition) or the association aspirin-alpha-tocopherol (54.4% inhibition). Nitric oxide production after 180 min reoxygenation was significantly reduced in aspirin (36.4%), alpha-tocopherol (22.7%) and aspirin-alpha-tocopherol (77.8%) treated rats with respect to diabetic non-treated animals; this was related mainly with a reduction in iNOS activity. The association between aspirin and alpha tocopherol could protects against brain ischemic-reperfusion damage with a better profile than aspirin alone.

  7. COMBINED MODULATION BY LEUCOVORIN AND ALPHA-2A INTERFERON OF FLUOROPYRIMIDINE MEDIATED GROWTH-INHIBITION

    NARCIS (Netherlands)

    SINNIGE, HAM; TIMMERBOSSCHA, H; PETERS, GF; DEVRIES, EGE; MULDER, NH

    1993-01-01

    One way to improve fluoropyrimidine activity is the use of kucovorin (LV). Another way is the use of alpha-2a interferon (a-IF). The mechanism of the a-IF effect on fluoropyrimidines has not yet been elucidated. Besides, only limited data area available on double modulation (LV and a-IF) of fluoropy

  8. Receptor-like protein-tyrosine phosphatase alpha specifically inhibits insulin-increased prolactin gene expression

    DEFF Research Database (Denmark)

    Jacob, K K; Sap, J; Stanley, F M

    1998-01-01

    A physiologically relevant response to insulin, stimulation of prolactin promoter activity in GH4 pituitary cells, was used as an assay to study the specificity of protein-tyrosine phosphatase function. Receptor-like protein-tyrosine phosphatase alpha (RPTPalpha) blocks the effect of insulin to i...

  9. Triptolide inhibits COX-2 expression by regulating mRNA stability in TNF-{alpha}-treated A549 cells

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Lixin; Zhang, Shuang; Jiang, Zhenzhou; Huang, Xin; Wang, Tao; Huang, Xiao; Li, Han [Jiangsu Center for Drug Screening, China Pharmaceutical University, Nanjing 210009 (China); Zhang, Luyong, E-mail: lyzhang@cpu.edu.cn [Jiangsu Center for Drug Screening, China Pharmaceutical University, Nanjing 210009 (China)

    2011-12-09

    Highlights: Black-Right-Pointing-Pointer Triptolide inhibited COX-2 expression and the half-life of COX-2 mRNA is decreased. Black-Right-Pointing-Pointer The HuR protein shuttling from nucleus to cytoplasm is inhibited by triptolide. Black-Right-Pointing-Pointer Triptolide inhibited 3 Prime -UTR fluorescence reporter gene activity. Black-Right-Pointing-Pointer COX-2 mRNA binding to HuR is decreased by triptolide in pull-down experiments. -- Abstract: Cyclooxygenase-2 (COX-2) over-expression is frequently associated with human non-small-cell lung cancer (NSCLC) and involved in tumor proliferation, invasion, angiogenesis and resistance to apoptosis. In the present study, the effects of triptolide on COX-2 expression in A549 cells were investigated and triptolide was found to inhibit TNF-{alpha}-induced COX-2 expression. In our further studies, it was found that triptolide decreased the half-life of COX-2 mRNA dramatically and that it inhibited 3 Prime -untranslated region (3 Prime -UTR) fluorescence reporter gene activity. Meanwhile, triptolide inhibited the HuR shuttling from nucleus to cytoplasm. After triptolide treatment, decreased COX-2 mRNA in pull-down experiments with anti-HuR antibodies was observed, indicating that the decreased cytoplasmic HuR is responsible for the decreased COX-2 mRNA. Taken together, our results provided evidence for the first time that triptolide inhibited COX-2 expression by COX-2 mRNA stability modulation and post-transcriptional regulation. These results provide a novel mechanism of action for triptolide which may be important in the treatment of lung cancer.

  10. DL-alpha-difluoromethylarginine inhibits intracellular Trypanosoma cruzi multiplication by affecting cell division but not trypomastigote-amastigote transformation.

    Science.gov (United States)

    Yakubu, M A; Basso, B; Kierszenbaum, F

    1992-06-01

    DL-alpha-difluoromethylarginine (DFMA), a specific, irreversible inhibitor of arginine decarboxylase (ADC), decreases the capacity of Trypanosoma cruzi to invade and multiply within different types of mammalian host cells in vitro. In this work we found that inhibition of intracellular growth results from selective impairment of amastigote division without appreciable alteration of the capacity of the invading trypomastigotes to transform into the replicative amastigote form. Addition of agmatine, the product of arginine decarboxylation, reversed the inhibitory effect of DFMA. Inhibition of ornithine decarboxylase activity by DL-alpha-difluoromethylornithine present in the medium prior to and during infection did not affect trypomastigote transformation or amastigote replication and did not change the magnitude of the inhibitory effect of DFMA on parasite multiplication. Hence, neither polyamine synthesis via the ornithine decarboxylase pathway nor salvage of host cell polyamines by T. cruzi appeared to be a likely explanation for the normal rate of parasite transformation that was seen in the presence of DFMA. Two clones of T. cruzi, TMSU-1 and TMSU-2, were tested for their degrees of sensitivity to the inhibitory effects of DFMA. Both trypomastigote association with (i.e., binding to and penetration of) myoblasts, and intracellular amastigote multiplication by either clone were found to be significantly (P less than 0.05) but not completely inhibited by DFMA. Therefore, the partial inhibition of T. cruzi infectivity and replication caused by DFMA is unlikely to represent a composite of effects of the drug on DFMA-sensitive and insensitive clones.(ABSTRACT TRUNCATED AT 250 WORDS)

  11. Preeclampsia -- a state of prostaglandin deficiency? Urinary prostaglandin excretion, the renin-aldosterone system, and circulating catecholamines in preeclampsia.

    Science.gov (United States)

    Pedersen, E B; Christensen, N J; Christensen, P; Johannesen, P; Kornerup, H J; Kristensen, S; Lauritsen, J G; Leyssac, P P; Rasmussen, A; Wohlert, M

    1983-01-01

    Urinary excretion of prostaglandin E2 (PGE2) and F2 alpha (PGF2 alpha), plasma concentrations of renin, aldosterone, norepinephrine (NE) and epinephrine (E) were determined during pregnancy, 5 days, 3, and 6 months after delivery in preeclampsia, normotensive pregnant, and nonpregnant control subjects. The PGE2 was higher in normotensive pregnant control subjects than in nonpregnant subjects. In preeclampsia, PGE2 was reduced to nonpregnant level. PGF2 alpha was the same in preeclampsia and in normotensive pregnancy, but elevated when compared to the normotensive nonpregnant control group. Plasma concentrations of renin and aldosterone were increased during pregnancy, but considerably less in preeclampsia than during normotensive pregnancy. NE and E were the same as in nonpregnant subjects during both hypertensive and normotensive pregnancy. All parameters were normal 3 months after delivery. There were no correlations between PGE2, PGF2 alpha, plasma concentrations of renin, aldosterone, NE, or E and blood pressure level in third trimester either in preeclampsia or in normotensive pregnancy. PGE2 was positively correlated to plasma concentrations of renin. It is suggested that the lack of renal PGE2 in preeclampsia might be responsible for the decrease in renal blood flow and sodium excretion. It is hypothesized that preeclampsia is a state of prostaglandin deficiency. The changes in the renin-aldosterone system may be secondary to changes in prostaglandin concentration both in preeclampsia and normotensive pregnancy.

  12. Peroxisome proliferator-activated receptor-gamma coactivator-1alpha activation of CYP7A1 during food restriction and diabetes is still inhibited by small heterodimer partner.

    Science.gov (United States)

    Shin, Dong-Ju; Osborne, Timothy F

    2008-05-30

    Cholesterol 7alpha-hydroxylase (CYP7A1) catalyzes the rate-limiting step in the classic pathway of hepatic bile acid biosynthesis from cholesterol. During fasting and in type I diabetes, elevated levels of peroxisome proliferator-activated receptor gamma-coactivator-1alpha (PGC-1alpha) induce expression of the Cyp7A1 gene and overexpression of PGC-1alpha in hepatoma cells stimulates bile acid synthesis. Using Ad-PGC-1alpha-RNA interference to induce acute disruption of PGC-1alpha in mice, here we show that PGC-1alpha is necessary for fasting-mediated induction of CYP7A1. Co-immunoprecipitation and promoter activation studies reveal that the induction of CYP7A1 is mediated by direct interaction between PGC-1alpha and the AF2 domain of liver receptor homolog-1 (LRH-1). In contrast, the very similar PGC-1beta could not substitute for PGC-1alpha. We also show that transactivation of PGC-1alpha and LRH-1 is repressed by the small heterodimer partner (SHP). Treatment of mice with GW4064, a synthetic agonist for farnesoid X receptor, induced SHP expression and decreased both the recruitment of PGC-1alpha to the Cyp7A1 promoter and the fasting-induced expression of CYP7A1 mRNA. These data suggest that PGC-1alpha is an important co-activator for LRH-1 and that SHP targets the interaction between LRH-1 and PGC-1alpha to inhibit CYP7A1 expression. Overall, these studies provide further evidence for the important role of PGC-1alpha in bile acid homeostasis and suggest that pharmacological targeting of farnesoid X receptor in vivo can be used to reverse the increase in CYP7A1 associated with adverse metabolic conditions.

  13. Inhibition of TNF-alpha induced cell death in human umbilical vein endothelial cells and Jurkat cells by protocatechuic acid.

    Science.gov (United States)

    Zhou-Stache, J; Buettner, R; Artmann, G; Mittermayer, C; Bosserhoff, A K

    2002-11-01

    The Chinese herb radix Salviae miltiorrhizae (RSM) is used in traditional Chinese medicine as a treatment for cardiovascular and cerebrovascular diseases. Several components of the plant extract from salvia mitorrhiza bunge have been determined previously, one of which is protocatechuic acid (PAC). It has been found, in the study, that PAC inhibited TNF-alpha-induced cell death of human umbilical vein endothelial cells (HUVECs) and Jurkat cells in a concentration of 100 microM when applied 2 h prior to TNF-alpha exposure. Molecular studies revealed that PAC activated NF-kappaB with a maximum effect after 30 min of treatment. Inhibition of NF-kappaB action by MG132 and NF-kappaB inhibitory peptide suppressed the cell-protective effect of PAC. Further, degradation of IkBalpha occurred in response to PAC treatment. The results provide evidence that activation of NF-kappaB plays an important role in mediating the cell-protecting effect of PAC on HUVECs and Jurkat cells. Further studies are required to test whether PAC, a component of radix salviae miltiorrhizae, could be useful in preventing in vivo cell death resulting from cardiovascular or cerebrovascular diseases.

  14. TNF-alpha inhibits 3T3-L1 adipocyte differentiation without downregulating the expression of C/EBPbeta and delta.

    Science.gov (United States)

    Kurebayashi, S; Sumitani, S; Kasayama, S; Jetten, A M; Hirose, T

    2001-04-01

    Tumor necrosis factor-alpha (TNF-alpha) has been reported to inhibit adipocyte differentiation in which multiple transcription factors including CCAAT enhancer binding proteins (C/EBPs) and peroxisome proliferator-activated receptor (PPAR) gamma play an important role. Induction of C/EBPalpha and PPARgamma, which regulate the expression of many adipocyte-related genes, is dependent on the expression of C/EBPbeta and C/EBPdelta at the early phase of adipocyte differentiation. To elucidate the mechanism by which TNF-alpha inhibits adipocyte differentiation, we examined the effect of TNF-alpha on the expression of these transcription factors in mouse 3T3-L1 preadipocytes. TNF-alpha did not abrogate the induction of C/EBPbeta and C/EBPdelta in response to differentiation stimuli. In fully differentiated adipocytes, TNF-alpha rapidly induced C/EBPbeta and C/EBPdelta, whereas it downregulated the expression of C/EBPalpha and PPARgamma. Our results suggest that TNF-alpha inhibits adipocyte differentiation independently of the downregulation of C/EBPbeta and C/EBPdelta.

  15. Inhibition of alpha oscillations through serotonin-2A receptor activation underlies the visual effects of ayahuasca in humans.

    Science.gov (United States)

    Valle, Marta; Maqueda, Ana Elda; Rabella, Mireia; Rodríguez-Pujadas, Aina; Antonijoan, Rosa Maria; Romero, Sergio; Alonso, Joan Francesc; Mañanas, Miquel Àngel; Barker, Steven; Friedlander, Pablo; Feilding, Amanda; Riba, Jordi

    2016-07-01

    Ayahuasca is an Amazonian psychotropic plant tea typically obtained from two plants, Banisteriopsis caapi and Psychotria viridis. It contains the psychedelic 5-HT2A and sigma-1 agonist N,N-dimethyltryptamine (DMT) plus β-carboline alkaloids with monoamine-oxidase (MAO)-inhibiting properties. Although the psychoactive effects of ayahuasca have commonly been attributed solely to agonism at the 5-HT2A receptor, the molecular target of classical psychedelics, this has not been tested experimentally. Here we wished to study the contribution of the 5-HT2A receptor to the neurophysiological and psychological effects of ayahuasca in humans. We measured drug-induced changes in spontaneous brain oscillations and subjective effects in a double-blind randomized placebo-controlled study involving the oral administration of ayahuasca (0.75mg DMT/kg body weight) and the 5-HT2A antagonist ketanserin (40mg). Twelve healthy, experienced psychedelic users (5 females) participated in four experimental sessions in which they received the following drug combinations: placebo+placebo, placebo+ayahuasca, ketanserin+placebo and ketanserin+ayahuasca. Ayahuasca induced EEG power decreases in the delta, theta and alpha frequency bands. Current density in alpha-band oscillations in parietal and occipital cortex was inversely correlated with the intensity of visual imagery induced by ayahuasca. Pretreatment with ketanserin inhibited neurophysiological modifications, reduced the correlation between alpha and visual effects, and attenuated the intensity of the subjective experience. These findings suggest that despite the chemical complexity of ayahuasca, 5-HT2A activation plays a key role in the neurophysiological and visual effects of ayahuasca in humans.

  16. Facilitation and inhibition in attention: Functional dissociation of pre-stimulus alpha activity, P1, and N1 components.

    Science.gov (United States)

    Slagter, H A; Prinssen, S; Reteig, L C; Mazaheri, A

    2016-01-15

    Attention--the ability to attend to some things while ignoring others - can be best described as an emergent property of many neural mechanisms, facilitatory and inhibitory, working together to resolve competition for processing resources and control of behavior. Previous EEG and MEG studies examining the neural mechanisms underlying facilitation and inhibition of stimulus processing typically used paradigms requiring alternating shifts of attention in the spatial domain, with stimuli occurring at both attended and unattended locations. These studies generally observed greater pre-stimulus alpha oscillations over task-irrelevant vs. relevant posterior regions and bilateral attentional modulations of early sensory processing. In contrast, in the current series of experiments, participants continuously attended to only one hemifield and stimuli were only presented at the attended location, affording us an opportunity to elucidate the inhibitory and facilitatory effects of attention in the brain in a context in which spatial relevance was fixed. We found that continuous attention to one hemifield did not modulate prestimulus alpha activity in ipsilateral regions but did result in a perfectly lateralized P1 attention effect to ipsilateral posterior regions. Moreover, we found a bilateral N1 effect. These findings suggest that pre-stimulus alpha activity, the P1 and the N1 reflect qualitatively different aspects of attention; While pre-stimulus alpha-band activity may reflect a top-down inhibitory mechanism that critically depends on functional competition between task-relevant and irrelevant sensory regions, the ipsilateral P1 effect may reflect stimulus-triggered blocking of sensory processing in irrelevant networks, and the N1 effect facilitation of task-relevant processing.

  17. Human Beta Cells Produce and Release Serotonin to Inhibit Glucagon Secretion from Alpha Cells

    OpenAIRE

    Joana Almaça; Judith Molina; Danusa Menegaz; Pronin, Alexey N.; Alejandro Tamayo; Vladlen Slepak; Per-Olof Berggren; Alejandro Caicedo

    2016-01-01

    In the pancreatic islet, serotonin is an autocrine signal increasing beta cell mass during metabolic challenges such as those associated with pregnancy or high-fat diet. It is still unclear whether serotonin is relevant for regular islet physiology and hormone secretion. Here, we show that human beta cells produce and secrete serotonin when stimulated with increases in glucose concentration. Serotonin secretion from beta cells decreases cyclic AMP (cAMP) levels in neighboring alpha cells via ...

  18. The inhibition of the human cholesterol 7alpha-hydroxylase gene (CYP7A1) promoter by fibrates in cultured cells is mediated via the liver x receptor alpha and peroxisome proliferator-activated receptor alpha heterodimer.

    Science.gov (United States)

    Gbaguidi, G Franck; Agellon, Luis B

    2004-01-01

    In previous work, we showed that the binding of the liver x receptor alpha:peroxisome proliferator-activated receptor alpha (LXRalpha:PPARalpha) heterodimer to the murine Cyp7a1 gene promoter antagonizes the stimulatory effect of their respective ligands. In this study, we determined if LXRalpha:PPARalpha can also regulate human CYP7A1 gene promoter activity. Co-expression of LXRalpha and PPARalpha in McArdle RH7777 hepatoma cells decreased the activity of the human CYP7A1 gene promoter in response to fibrates and 25-hydroxycholesterol. In vitro, the human CYP7A1 Site I bound LXRalpha:PPARalpha, although with substantially less affinity compared with the murine Cyp7a1 Site I. The binding of LXRalpha:PPARalpha to human CYP7A1 Site I was increased in the presence of either LXRalpha or PPARalpha ligands. In HepG2 hepatoblastoma cells, fibrates and 25-hydroxycholesterol inhibited the expression of the endogenous CYP7A1 gene as well as the human CYP7A1 gene promoter when co-transfected with plasmids encoding LXRalpha and PPARalpha. However, a derivative of the human CYP7A1 gene promoter that contains a mutant form of Site I that does not bind LXRalpha:PPARalpha was not inhibited by WY 14,643 or 25-hydroxycholesterol in both McArdle RH7777 and HepG2 cells. The ligand-dependent recruitment of LXRalpha:PPARalpha heterodimer onto the human CYP7A1 Site I can explain the inhibition of the human CYP7A1 gene promoter in response to fibrates and 25-hydroxycholesterol.

  19. Constitutive expression of MC1R in HaCaT keratinocytes inhibits basal and UVB-induced TNF-alpha production.

    Science.gov (United States)

    Garcin, Geneviève; Le Gallic, Lionel; Stoebner, Pierre-Emmanuel; Guezennec, Anne; Guesnet, Joelle; Lavabre-Bertrand, Thierry; Martinez, Jean; Meunier, Laurent

    2009-01-01

    Alpha-melanocyte stimulating hormone (alpha-MSH) binds to melanocortin-1 receptor (MC1R) on melanocytes to stimulate pigmentation and modulate various cutaneous inflammatory responses. MC1R expression is not restricted to melanocytic cells and may be induced in keratinocytes after UVB exposure. We hypothesized that MC1R signaling in keratinocytes, wherein basal conditions are barely expressed, may modulate mediators of inflammation, such as nuclear factor-kappa B (NF-kappaB) and tumor necrosis factor-alpha (TNF-alpha). Therefore, we generated HaCaT cells that stably express human MC1R or the Arg151Cys (R151C) nonfunctional variant. We demonstrate that: (1) the constitutive activity of MC1R results in elevated intracellular cAMP level, reduced NF-kappaB activity and decreased TNF-alpha transcription; (2) binding of alpha-MSH to MC1R and the subsequent increase in cAMP production do not inhibit TNFalpha-mediated NF-kappaB activation; (3) MC1R signaling is sufficient to strongly inhibit UVB-induced TNF-alpha expression and this inhibitory effect is further enhanced by alpha-MSH stimulation. Our findings suggest that the constitutive activity of the G-protein-coupled MC1R in keratinocytes may contribute to the modulation of inflammatory events and immune response induced by UV light.

  20. Additivity of water sorption, alpha-relaxations and crystallization inhibition in lactose-maltodextrin systems.

    Science.gov (United States)

    Potes, Naritchaya; Kerry, Joseph P; Roos, Yrjö H

    2012-08-01

    Water sorption of lactose-maltodextrin (MD) systems, structural relaxations and lactose crystallization were studied. Accurate water sorption data for non-crystalline lactose previously not available over a wide range of water activity, aw (maltodextrin (MD) systems were strongly affected by water and MD. At high MD contents, inhibition of crystallization was significant. Inhibition with a high dextrose equivalent (DE) MD was more pronounced possibly because of molecular number and size effects. At 0.55-0.76aw, inhibition increased with increasing MD content. At aw>0.66, the rate of lactose crystallization decreased at increasing MD contents. Different MDs with similar Tg in lactose-MD systems showed different crystallization inhibition effects. The results of the present study showed that the DE in selection of MD for applications has important effects on component crystallization characteristics.

  1. Inhibition of nitric oxide synthesis by systemic N(G)-monomethyl-L-arginine administration in humans

    DEFF Research Database (Denmark)

    Frandsen, U; Bangsbo, J; Langberg, Henning;

    2000-01-01

    We examined whether the formation or the release of the vasodilators adenosine, prostacyclin (PGI(2)) and potassium (K(+)) increase in skeletal muscle interstitium in response to nitric oxide synthase (NOS) inhibition. Five subjects performed one-legged knee extensor exercise at 30 W without (con......-keto-prostaglandin F1alpha concentration in controls was 1.17+/-0.20 ng/ml at rest and increased (p0.05) in L-NAME. The interstitial K(+) concentration in controls increased (p...

  2. Tat-APE1/ref-1 protein inhibits TNF-alpha-induced endothelial cell activation.

    Science.gov (United States)

    Song, Yun Jeong; Lee, Ji Young; Joo, Hee Kyoung; Kim, Hyo Shin; Lee, Sang Ki; Lee, Kwon Ho; Cho, Chung-Hyun; Park, Jin Bong; Jeon, Byeong Hwa

    2008-03-28

    Apurinic/apyrimidinic endonuclease 1/redox factor-1 (APE1/ref-1) is a multifunctional protein involved both in DNA base excision repair and redox regulation. In this study we evaluated the protective role of Tat-mediated APE1/ref-1 transduction on the tumor necrosis factor (TNF)-alpha-activated endothelial activation in cultured human umbilical vein endothelial cells. To construct Tat-APE1/ref-1 fusion protein, human full length of APE1/ref-1 was fused with Tat-protein transduction domain. Purified Tat-APE1/ref-1 fusion protein efficiently transduced cultured endothelial cells in a dose-dependent manner and reached maximum expression at 1h after incubation. Transduced Tat-APE1/ref-1 showed inhibitory activity on the TNF-alpha-induced monocyte adhesion and vascular cell adhesion molecule-1 expression in cultured endothelial cells. These results suggest Tat-APE1/ref-1 might be useful to reduce vascular endothelial activation or vascular inflammatory disorders.

  3. Telomerase inhibition decreases alpha-fetoprotein expression and secretion by hepatocellular carcinoma cell lines: in vitro and in vivo study.

    Directory of Open Access Journals (Sweden)

    Roula Tahtouh

    Full Text Available Alpha-fetoprotein (AFP is a diagnostic marker for hepatocellular carcinoma (HCC. A direct relationship between poor prognosis and the concentration of serum AFP has been observed. Telomerase, an enzyme that stabilizes the telomere length, is expressed by 90% of HCC. The aim of this study was to investigate the effect of telomerase inhibition on AFP secretion and the involvement of the PI3K/Akt/mTOR signaling pathway. Proliferation and viability tests were performed using tetrazolium salt. Apoptosis was determined through the Annexin V assay using flow cytometry. The concentrations of AFP were measured using ELISA kits. The AFP mRNA expression was evaluated using RT-PCR, and cell migration was evaluated using a Boyden chamber assay. The in vivo effect of costunolide on AFP production was tested in NSG mice. Telomerase inhibition by costunolide and BIBR 1532 at 5 and 10 μM decreased AFP mRNA expression and protein secretion by HepG2/C3A cells. The same pattern was obtained with cells treated with hTERT siRNA. This treatment exhibited no apoptotic effect. The AFP mRNA expression and protein secretion by PLC/PRF/5 was decreased after treatment with BIBR1532 at 10 μM. In contrast, no effect was obtained for PLC/PRF/5 cells treated with costunolide at 5 or 10 μM. Inhibition of the PI3K/Akt/mTOR signaling pathway decreased the AFP concentration. In contrast, the MAPK/ERK pathway appeared to not be involved in HepG2/C3A cells, whereas ERK inhibition decreased the AFP concentration in PLC/PRF/5 cells. Modulation of the AFP concentration was also obtained after the inhibition or activation of PKC. Costunolide (30 mg/kg significantly decreased the AFP serum concentration of NSG mice bearing HepG2/C3A cells. Both the inhibition of telomerase and the inhibition of the PI3K/Akt/mTOR signaling pathway decreased the AFP production of HepG2/C3A and PLC/PRF/5 cells, suggesting a relationship between telomerase and AFP expression through the PI3K

  4. Inhibition of adipocyte differentiation by resistin-like molecule alpha. Biochemical characterization of its oligomeric nature

    DEFF Research Database (Denmark)

    Blagoev, Blagoy; Kratchmarova, Irina; Nielsen, Mogens M;

    2002-01-01

    of thiazolidinediones. The prototypical member of this family was originally identified from bronchoalveolar lavage fluid of inflamed lungs and designated FIZZ1 ("found in inflammatory zone"). This molecule was also found to be highly expressed in adipose tissue and was named resistin-like molecule alpha (RELMalpha...... as well as by mass spectrometry. In addition, RELMalpha is able to form heterooligomers with resistin but not RELMbeta. Since RELMalpha is expressed by adipose tissue and it is a secreted factor, our findings suggest that RELMalpha may be involved in the control of the adipogenesis as well......A novel family of cysteine-rich secreted proteins with unique tissue distribution has recently been identified. One of the members, resistin (for "resistance to insulin"), also called FIZZ3, was identified in a screen for molecules that are down-regulated in mature adipocytes upon administration...

  5. Tyrosol and Its Analogues Inhibit Alpha-Melanocyte-Stimulating Hormone Induced Melanogenesis

    Directory of Open Access Journals (Sweden)

    Kuo-Ching Wen

    2013-11-01

    Full Text Available Melanin is responsible for skin color and plays a major role in defending against harmful external factors such as ultraviolet (UV irradiation. Tyrosinase is responsible for the critical steps of melanogenesis, including the rate-limiting step of tyrosine hydroxylation. The mechanisms of action of skin hypopigmenting agents are thought to be based on the ability of a given agent to inhibit the activity of tyrosinase and, hence, down regulate melanin synthesis. Tyrosol and its glycoside, salidroside, are active components of Rhodiola rosea, and in our preliminary study we found that Rhodiola rosea extract inhibited melanogenesis. In this study, we examined the effects of tyrosol and its analogues on melanin synthesis. We found that treatment of B16F0 cells to tyrosol (1, 4-hydroxyphenylacetic acid (5, 3-hydroxyphenylacetic acid (6, 2-hydroxyphenylacetic acid (7, or salidroside (11 resulted in a reduction in melanin content and inhibition of tyrosinase activity as well as its expression. Tyrosol (1, 4-hydroxyphenylacetic acid (5 and 2-hydroxyphenylacetic acid (7 suppressed MC1R expression. Tyrosol (1, 4-hydroxyphenylacetic acid (5, 3-hydroxyphenylacetic acid (6, and 2-hydroxyphenylacetic acid (7 inhibited α-MSH induced TRP-1 expression, but salidroside (11 did not. All the compounds did not affect MITF and TRP-2 expression. Furthermore, we found that the cell viability of tyrosol (1, 4-hydroxyphenylacetic acid (5, 3-hydroxyphenylacetic acid (6, and 2-hydroxyphenylacetic acid (7 at concentrations below 4 mM and salidroside (11 at concentrations below 0.5 mM were higher than 90%. The compounds exhibited metal-coordinating interactions with copper ion in molecular docking with tyrosinase. Our results suggest that tyrosol, 4-hydroxyphenylacetic acid, 3-hydroxyphenylacetic acid, 2-hydroxyphenylacetic acid, and salidroside are potential hypopigmenting agents.

  6. Tyrosol and its analogues inhibit alpha-melanocyte-stimulating hormone induced melanogenesis.

    Science.gov (United States)

    Wen, Kuo-Ching; Chang, Chih-Shiang; Chien, Yin-Chih; Wang, Hsiao-Wen; Wu, Wan-Chen; Wu, Chin-Sheng; Chiang, Hsiu-Mei

    2013-11-28

    Melanin is responsible for skin color and plays a major role in defending against harmful external factors such as ultraviolet (UV) irradiation. Tyrosinase is responsible for the critical steps of melanogenesis, including the rate-limiting step of tyrosine hydroxylation. The mechanisms of action of skin hypopigmenting agents are thought to be based on the ability of a given agent to inhibit the activity of tyrosinase and, hence, down regulate melanin synthesis. Tyrosol and its glycoside, salidroside, are active components of Rhodiola rosea, and in our preliminary study we found that Rhodiola rosea extract inhibited melanogenesis. In this study, we examined the effects of tyrosol and its analogues on melanin synthesis. We found that treatment of B16F0 cells to tyrosol (1), 4-hydroxyphenylacetic acid (5), 3-hydroxyphenylacetic acid (6), 2-hydroxyphenylacetic acid (7), or salidroside (11) resulted in a reduction in melanin content and inhibition of tyrosinase activity as well as its expression. Tyrosol (1), 4-hydroxyphenylacetic acid (5) and 2-hydroxyphenylacetic acid (7) suppressed MC1R expression. Tyrosol (1), 4-hydroxyphenylacetic acid (5), 3-hydroxyphenylacetic acid (6), and 2-hydroxyphenylacetic acid (7) inhibited α-MSH induced TRP-1 expression, but salidroside (11) did not. All the compounds did not affect MITF and TRP-2 expression. Furthermore, we found that the cell viability of tyrosol (1), 4-hydroxyphenylacetic acid (5), 3-hydroxyphenylacetic acid (6), and 2-hydroxyphenylacetic acid (7) at concentrations below 4 mM and salidroside (11) at concentrations below 0.5 mM were higher than 90%. The compounds exhibited metal-coordinating interactions with copper ion in molecular docking with tyrosinase. Our results suggest that tyrosol, 4-hydroxyphenylacetic acid, 3-hydroxyphenylacetic acid, 2-hydroxyphenylacetic acid, and salidroside are potential hypopigmenting agents.

  7. Fluid shear stress inhibits TNF-alpha-induced apoptosis in osteoblasts: a role for fluid shear stress-induced activation of PI3-kinase and inhibition of caspase-3

    Science.gov (United States)

    Pavalko, Fredrick M.; Gerard, Rita L.; Ponik, Suzanne M.; Gallagher, Patricia J.; Jin, Yijun; Norvell, Suzanne M.

    2003-01-01

    In bone, a large proportion of osteoblasts, the cells responsible for deposition of new bone, normally undergo programmed cell death (apoptosis). Because mechanical loading of bone increases the rate of new bone formation, we hypothesized that mechanical stimulation of osteoblasts might increase their survival. To test this hypothesis, we investigated the effects of fluid shear stress (FSS) on osteoblast apoptosis using three osteoblast cell types: primary rat calvarial osteoblasts (RCOB), MC3T3-E1 osteoblastic cells, and UMR106 osteosarcoma cells. Cells were treated with TNF-alpha in the presence of cyclohexamide (CHX) to rapidly induce apoptosis. Osteoblasts showed significant signs of apoptosis within 4-6 h of exposure to TNF-alpha and CHX, and application of FSS (12 dyne/cm(2)) significantly attenuated this TNF-alpha-induced apoptosis. FSS activated PI3-kinase signaling, induced phosphorylation of Akt, and inhibited TNF-alpha-induced activation of caspase-3. Inhibition of PI3-kinase, using LY294002, blocked the ability of FSS to rescue osteoblasts from TNF-alpha-induced apoptosis and blocked FSS-induced inhibition of caspase-3 activation in osteoblasts treated with TNF-alpha. LY294002 did not, however, prevent FSS-induced phosphorylation of Akt suggesting that activation of Akt alone is not sufficient to rescue cells from apoptosis. This result also suggests that FSS can activate Akt via a PI3-kinase-independent pathway. These studies demonstrate for the first time that application of FSS to osteoblasts in vitro results in inhibition of TNF-alpha-induced apoptosis through a mechanism involving activation of PI3-kinase signaling and inhibition of caspases. FSS-induced activation of PI3-kinase may promote cell survival through a mechanism that is distinct from the Akt-mediated survival pathway. Copyright 2002 Wiley-Liss, Inc.

  8. Inhibition of internal ribosomal entry site-directed translation of HCV by recombinant IFN-alpha correlates with a reduced La protein.

    Science.gov (United States)

    Shimazaki, Takeo; Honda, Masao; Kaneko, Shuichi; Kobayashi, Kenichi

    2002-01-01

    Translation of the hepatitis C virus (HCV) polyprotein is mediated by an internal ribosome entry site (IRES) that is located within the 5'-nontranslated region (5'NTR). We investigated the effect of interferon alfa (IFN-alpha) on the IRES-directed translation of HCV, using two stably transformed cell lines, RCF-1 and RCF-26, of Huh7 cells derived from human hepatocellular carcinoma that express dicistronic reporter proteins, Renilla luciferase (RL) and firefly luciferase (FL), separated by HCV-IRES. After the administration of IFN-alpha or poly(I)-poly(C), HCV-IRES-directed translation was inhibited in a dose-dependent manner. The relative HCV-IRES activity (F/L) decreased to 60% at 5,000 IU/mL of IFN-alpha and 45% at 40 microg/mL of poly(I)-poly(C). Thus, IFN-alpha or poly(I)-poly(C) inhibited HCV-IRES-directed translation more efficiently than a cellular cap-dependent translation. 2',5'-oligoadenylate synthetase (2',5'AS) protein level in cells analyzed significantly increased after the administration of IFN-alpha, but not upon poly(I)-poly(C). Overexpression of double-stranded RNA-activated protein kinase (PKR) gene did not mimic the selective inhibition of HCV-IRES-directed translation in the transformant cells, suggesting that neither the 2',5'AS nor the PKR system are involved in this selective inhibition. Interestingly, the expression of the autoantigen, La, which has been reported to enhance HCV-IRES-directed translation, was significantly reduced after the administration of IFN-alpha and poly(I)-poly(C) in a dose-dependent manner. Transient expression of La protein completely restored the selective inhibition of HCV-IRES-directed translation by IFN-alpha and poly(I)-poly(C). These findings suggested a new antiviral mechanism induced by IFN-alpha in that IFN-alpha or poly(I)-poly(C) selectively inhibited HCV-IRES-directed translation compared with the eukaryotic cap-dependent translation through the reduction of La protein.

  9. Activated AMPK inhibits PPAR-{alpha} and PPAR-{gamma} transcriptional activity in hepatoma cells.

    Science.gov (United States)

    Sozio, Margaret S; Lu, Changyue; Zeng, Yan; Liangpunsakul, Suthat; Crabb, David W

    2011-10-01

    AMP-activated protein kinase (AMPK) and peroxisome proliferator-activated receptor-α (PPAR-α) are critical regulators of short-term and long-term fatty acid oxidation, respectively. We examined whether the activities of these molecules were coordinately regulated. H4IIEC3 cells were transfected with PPAR-α and PPAR-γ expression plasmids and a peroxisome-proliferator-response element (PPRE) luciferase reporter plasmid. The cells were treated with PPAR agonists (WY-14,643 and rosiglitazone), AMPK activators 5-aminoimidazole-4-carboxamide riboside (AICAR) and metformin, and the AMPK inhibitor compound C. Both AICAR and metformin decreased basal and WY-14,643-stimulated PPAR-α activity; compound C increased agonist-stimulated reporter activity and partially reversed the effect of the AMPK activators. Similar effects on PPAR-γ were seen, with both AICAR and metformin inhibiting PPRE reporter activity. Compound C increased basal PPAR-γ activity and rosiglitazone-stimulated activity. In contrast, retinoic acid receptor-α (RAR-α), another nuclear receptor that dimerizes with retinoid X receptor (RXR), was largely unaffected by the AMPK activators. Compound C modestly increased AM580 (an RAR agonist)-stimulated activity. The AMPK activators did not affect PPAR-α binding to DNA, and there was no consistent correlation between effects of the AMPK activators and inhibitor on PPAR and the nuclear localization of AMPK-α subunits. Expression of either a constitutively active or dominant negative AMPK-α inhibited basal and WY-14,643-stimulated PPAR-α activity and basal and rosiglitazone-stimulated PPAR-γ activity. We concluded that the AMPK activators AICAR and metformin inhibited transcriptional activities of PPAR-α and PPAR-γ, whereas inhibition of AMPK with compound C activated both PPARs. The effects of AMPK do not appear to be mediated through effects on RXR or on PPAR/RXR binding to DNA. These effects are independent of kinase activity and instead appear to

  10. Mutual interactions of the presynaptic histamine H3 and prostaglandin EP3 receptors on the noradrenergic terminals in the mouse brain.

    Science.gov (United States)

    Schlicker, E; Marr, I

    1997-07-01

    We studied whether interactions between the presynaptic histamine H3 and prostaglandin EP3 receptors on the noradrenergic neurons of the mouse brain cortex occur. Cerebral cortex slices from the mouse (and, in few experiments, from the rat) were preincubated with [3H]noradrenaline and then superfused with a physiological salt solution. Tritium overflow was evoked electrically, either at 0.3 or 3 Hz (2 min) (standard stimulation protocol) or at 100 Hz (eight pulses) (stimulation protocol under which almost no activation of the presynaptic alpha2-adrenoceptors by endogenous noradrenaline occurs). In another set of experiments, Ca2+ ions were introduced into Ca2+-free K+-rich medium containing tetrodotoxin to evoke tritium overflow. The electrically-evoked tritium overflow (0.3 Hz) was inhibited by histamine or the H3 receptor agonist imetit, acting via H3 receptors. and by prostaglandin E2 or the EP3 receptor agonist sulprostone, acting via EP3 receptors. When histamine or imetit was given first (at concentrations causing the maximum effect at H3 receptors), the effect of prostaglandin E2 on the evoked tritium overflow was attenuated by 5-10%. When prostaglandin E2 or sulprostone was given first (at concentrations causing the maximum effect at EP3 receptors), the effect of histamine or imetit on the evoked overflow was attenuated by almost 50%. The previous administration of prostaglandin E2 also blunted the effect of histamine on the evoked tritium overflow evoked at 3 Hz; the degree of attenuation was identical when the current strength was 25 mA or was increased to 100 or 200 mA in order to partially compensate for the inhibitory effect of prostaglandin E2 on the evoked overflow. In addition, prostaglandin E2 attenuated the effect of histamine when tritium overflow was evoked (i) by 100 Hz, eight pulses or (ii) by Ca2+ ions or (iii) when rat (instead of mouse) brain cortex slices were used. An interaction of prostaglandin E2 or sulprostone with the H3 receptor

  11. Liquid chromatography-high resolution mass spectrometry with immunoaffinity clean-up for the determination of the oxidative stress biomarker 8-iso-prostaglandin F2alpha in wastewater.

    Science.gov (United States)

    Ryu, Yeonsuk; Reid, Malcolm J; Thomas, Kevin V

    2015-08-28

    A reliable oxidative stress biomarker, 8-iso-prostaglandin F2α (8-iso-PGF2α), was for the first time quantitatively analysed in wastewater using an analytical method consisting of liquid chromatography-high resolution mass spectrometry coupled to immunoaffinity clean-up (IAC-LC-HRMS). Factors influencing the method's robustness were investigated, including analyte stability in sewage and enzymatic deconjugation with β-glucuronidase. The IAC-LC-HRMS method was linear over the range of 0.1-100ng/mL with correlation coefficient (R(2)) of 0.999. The quantification limits were sufficiently low to detect 8-iso-PGF2α in sewage (method quantification limit of 0.3ng/L) and precision, expressed as relative standard deviation was less than 7% and the accuracy expressed as relative recovery was in the 103-113% range. As a result, the application of the method to 24-h composite wastewater samples from Oslo showed 8-iso-PGF2α concentrations of 18.9-23.3ng/L for 8 days in March 2015. This study demonstrates a standard method to analyse 8-iso-PGF2α in sewage that will contribute to the further investigation of the potential use of 8-iso-PGF2α as a sewage biomarker for assessing the status of community health.

  12. Overexpression of protein tyrosine phosphatase-alpha (PTP-alpha) but not PTP-kappa inhibits translocation of GLUT4 in rat adipose cells

    DEFF Research Database (Denmark)

    Cong, L N; Chen, H; Li, Y

    1999-01-01

    either wild-type PTP-kappa or catalytically inactive mutants of PTP-alpha had dose-response curves similar to those of control cells. Since overexpression of PTP-alpha, but not PTP-kappa, had effects on translocation of GLUT4, our data suggest that PTPalpha may be a specific negative modulator of insulin...

  13. Effects and Interactions of Prostaglandins and Interferon-γ on Steroidogenesis of Human Luteal Cells

    Institute of Scientific and Technical Information of China (English)

    王寒正; 沈维维; 孙志达; 张翔; 龚岳亭

    1996-01-01

    Previous work from our laboratory has demonstrated that T lymphocyte-derived cytokine, interferon-gamma (IFN-γ) may play a role in human luteal regression by inhibiting luteal progesterone production. Prostaglandin F2a has been known as an important luteolytic factor in a wide range of mammalian species. It was of interest to investigate the effects of IFN-γ on prostaglandin synthesis and their possible interaction with the inhibition on human luteal steroidogenesis. Human luteal cells were cultured for four days in the presence or absence of IFN-γ. Simultaneously, the productions of progesterone, prostaglandin F2a ( PGF2a ), prostaglandin E2 ( PGE2 ), and 6-ketoprostaglandin F1a(PGF1a) were evaluated. Concomitant with the inhibition of progesterone production induced by IFN-γ, a biphasic pattern of response of. prostaglandin synthesis was observed, i.e. a slight decrease of PGF2a and PGF1a after a 48 h exposure to IFN-γ while an increase of PGE2 after 96 h. In a separate experiment, a luteotropic action of PGE2 and PGF2a on human luteal cells from different stages was observed during 48 and 96 h periods of culture. In addition, while indomethacin (INDO) treatment markedly blocked the prostaglandin synthesis, the basal as well as hCG stimulated progesterone production was still inhibited by IFN-γ as usual. These results suggested that prostaglandins appeared to be not responsible for the observed inhibition of progesterone production since the inhibitory effect was not influenced by concurrent treatment with INDO which suppressed prostaglandin synthesis,

  14. Inhibition of diacylglycerol kinase alpha restores restimulation-induced cell death and reduces immunopathology in XLP-1

    Science.gov (United States)

    Ruffo, Elisa; Malacarne, Valeria; Larsen, Sasha E.; Das, Rupali; Patrussi, Laura; Wülfing, Christoph; Biskup, Christoph; Kapnick, Senta M.; Verbist, Katherine; Tedrick, Paige; Schwartzberg, Pamela L.; Baldari, Cosima T.; Rubio, Ignacio; Nichols, Kim E.; Snow, Andrew L.; Baldanzi, Gianluca; Graziani, Andrea

    2016-01-01

    X-linked lymphoproliferative disease (XLP-1) is an often-fatal primary immunodeficiency associated with the exuberant expansion of activated CD8+ T cells following Epstein-Barr virus (EBV) infection. XLP-1 is caused by defects in SAP, an adaptor protein that modulates T cell receptor (TCR)-induced signaling. SAP-deficient T cells exhibit impaired TCR restimulation-induced cell death (RICD) and diminished TCR-induced inhibition of diacylglycerol kinase alpha (DGKα), leading to increased diacylglycerol metabolism and decreased signaling through Ras and PKCθ. Here, we show that down-regulation of DGKα activity in SAP-deficient T cells restores diacylglycerol signaling at the immune synapse and rescues RICD via induction of the pro-apoptotic proteins NUR77 and NOR1. Importantly, pharmacological inhibition of DGKα prevents the excessive CD8+ T cell expansion and IFNγ production that occur in Sap-deficient mice following Lymphocytic Choriomeningitis Virus infection without impairing lytic activity. Collectively, these data highlight DGKα as a viable therapeutic target to reverse the life-threatening EBV-associated immunopathology that occurs in XLP-1 patients. PMID:26764158

  15. Tumour necrosis factor-alpha and interleukin-8 inhibit neutrophil migration in vitro and in vivo

    Directory of Open Access Journals (Sweden)

    F. Q. Cunha

    1992-01-01

    Full Text Available Pretreatment of human neutrophils with recombinant tumour necrosis factor-alpha (rTNF-α and/or interleukin-8 (rIL-8, but not with either transforming growth factor-beta, interleukin-6 or interferon-gamma, rendered these cells less responsive to FMLP, in microchemotaxis assays. This inhibitory effect was dose dependent and more powerful when neutrophils were pretreated with a mixture of both cytokines. Intravenous injection of human rIL-8 (hrIL-8 and/or murine rTNF-α (mrTNF-α also significantly reduced in vivo neutrophil migration into peritoneal cavities of rats stimulated with carrageenan. These data suggest that the defect in neutrophil migration during septicaemia or endotoxaemia may be the result of the continuous release of IL-8 and TNF-α into the circulation. Thus, either the selective control or blockade of releasing of these cytokines as well as of its effects on neutrophils may be clinically useful in reestablishing the cell defence mechanisms.

  16. Induction of apoptosis in cholangiocarcinoma by an andrographolide analogue is mediated through topoisomerase II alpha inhibition.

    Science.gov (United States)

    Nateewattana, Jintapat; Dutta, Suman; Reabroi, Somrudee; Saeeng, Rungnapha; Kasemsook, Sakkasem; Chairoungdua, Arthit; Weerachayaphorn, Jittima; Wongkham, Sopit; Piyachaturawat, Pawinee

    2014-01-15

    Cholangiocarcinoma (CCA), the common primary malignant tumor of bile duct epithelial cells, is unresponsive to most chemotherapeutic drugs. Diagnosis with CCA has a poor prognosis, and therefore urgently requires effective therapeutic agents. In the present study we investigated anti-cancer effects of andrographolide analogue 3A.1 (19-tert-butyldiphenylsilyl-8, 17-epoxy andrographolide) and its mechanism in human CCA cell line KKU-M213 derived from a Thai CCA patient. By 24h after exposure, the analogue 3A.1 exhibited a potent cytotoxic effect on KKU-M213 cells with an inhibition concentration 50 (IC50) of approximately 8.0µM. Analogue 3A.1 suppressed DNA topoisomerase II α (Topo II α) protein expression, arrested the cell cycle at sub G0/G1 phase, induced cleavage of DNA repair protein poly (ADP-ribose) polymerases-1 (PARP-1), and enhanced expression of tumor suppressor protein p53 and pro-apoptotic protein Bax. In addition, analogue 3A.1 induced caspase 3 activity and inhibited cyclin D1, CDK6, and COX-2 protein expression. These results suggest that andrographolide analogue 3A.1, a novel topo II inhibitor, has significant potential to be developed as a new anticancer agent for the treatment of CCA.

  17. Insulin-like growth factor-binding protein-5 (IGFBP-5) inhibits TNF-{alpha}-induced NF-{kappa}B activity by binding to TNFR1

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Jae Ryoung; Huh, Jae Ho; Lee, Yoonna; Lee, Sang Il [Molecular Therapy Research Center, Sungkyunkwan University, Seoul 135-710 (Korea, Republic of); Rho, Seung Bae [Research Institute, National Cancer Center, Goyang-si, Gyeonggi-do 411-769 (Korea, Republic of); Lee, Je-Ho, E-mail: jeholee@gmail.com [Molecular Therapy Research Center, Sungkyunkwan University, Seoul 135-710 (Korea, Republic of); Department of Obstetrics and Gynecology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

    2011-02-25

    Research highlights: {yields} Binding assays demonstrated that secreted- and cellular-IGFBP-5 interacted with TNFR1. {yields} The interaction between IGFBP-5 and TNFR1 was inhibited by TNF-{alpha} and was blocked TNF-{alpha}-activated NF-{kappa}B activity. {yields} IGFBP-5 interacted with TNFR1 through its N- and L-domains but the binding of L-domain to TNFR1 was blocked by TNF-{alpha}. {yields} Competition between the L-domain of IGFBP-5 and TNF-{alpha} blocked TNF-{alpha}-induced NF-{kappa}B activity. {yields} This study suggests that the L-domain of IGFBP-5 is a novel TNFR1 ligand that functions as a competitive TNF-{alpha} inhibitor. -- Abstract: IGFBP-5 is known to be involved in various cell phenomena such as proliferation, differentiation, and apoptosis. However, the exact mechanisms by which IGFBP-5 exerts its functions are unclear. In this study, we demonstrate for the first time that IGFBP-5 is a TNFR1-interacting protein. We found that ectopic expression of IGFBP-5 induced TNFR1 gene expression, and that IGFBP-5 interacted with TNFR1 in both an in vivo and an in vitro system. Secreted IGFBP-5 interacted with GST-TNFR1 and this interaction was blocked by TNF-{alpha}, demonstrating that IGFBP-5 might be a TNFR1 ligand. Furthermore, conditioned media containing secreted IGFBP-5 inhibited PMA-induced NF-{kappa}B activity and IL-6 expression in U-937 cells. Coimmunoprecipitation assays of TNFR1 and IGFBP-5 wild-type and truncation mutants revealed that IGFBP-5 interacts with TNFR1 through its N- and L-domains. However, only the interaction between the L-domain of IGFBP-5 and TNFR1 was blocked by TNF-{alpha} in a dose-dependent manner, suggesting that the L-domain of IGFBP-5 can function as a TNFR1 ligand. Competition between the L-domain of IGFBP-5 and TNF-{alpha} resulted in inhibition of TNF-{alpha}-induced NF-{kappa}{Beta} activity. Taken together, our results suggest that the L-domain of IGFBP-5 is a novel TNFR1 ligand that functions as a competitive TNF-{alpha

  18. Ribavirin inhibits in vitro hepatitis E virus replication through depletion of cellular GTP pools and is moderately synergistic with alpha interferon

    NARCIS (Netherlands)

    Y. Debing (Yannick); B. Emerson; Y. Wang (Yijin); Q. Pan (Qiuwei); J. Balzarini; K. Dallmeier (Kai); J. Neyts

    2014-01-01

    textabstractHepatitis E virus (HEV) is a common cause of acute hepatitis that results in high mortality in pregnant women and may establish chronic infections in immunocompromised patients. We demonstrate for the first time that alpha interferon (IFN-α) and ribavirin inhibit in vitro HEV replication

  19. Modelling Ser129 phosphorylation inhibits membrane binding of pore-forming alpha-synuclein oligomers.

    Directory of Open Access Journals (Sweden)

    Georg Sebastian Nübling

    Full Text Available BACKGROUND: In several neurodegenerative diseases, hyperphosphorylation at position Ser129 is found in fibrillar deposits of alpha-synuclein (asyn, implying a pathophysiological role of asyn phosphorylation in neurodegeneration. However, recent animal models applying asyn phosphorylation mimics demonstrated a protective effect of phosphorylation. Since metal-ion induced asyn oligomers were identified as a potential neurotoxic aggregate species with membrane pore-forming abilities, the current study was undertaken to determine effects of asyn phosphorylation on oligomer membrane binding. METHODS: We investigated the influence of S129 phosphorylation on interactions of metal-ion induced asyn oligomers with small unilamellar lipid vesicles (SUV composed of POPC and DPPC applying the phosphorylation mimic asyn129E. Confocal single-particle fluorescence techniques were used to monitor membrane binding at the single-particle level. RESULTS: Binding of asyn129E monomers to gel-state membranes (DPPC-SUV is slightly reduced compared to wild-type asyn, while no interactions with membranes in the liquid-crystalline state (POPC-SUV are seen for both asyn and asyn129E. Conversely, metal-ion induced oligomer formation is markedly increased in asyn129E. Surprisingly, membrane binding to POPC-SUV is nearly absent in Fe(3+ induced asyn129E oligomers and markedly reduced in Al(3+ induced oligomers. CONCLUSION: The protective effect of pseudophosphorylation seen in animal models may be due to impeded oligomer membrane binding. Phosphorylation at Ser129 may thus have a protective effect against neurotoxic asyn oligomers by preventing oligomer membrane binding and disruption of the cellular electrophysiological equilibrium. Importantly, these findings put a new complexion on experimental pharmaceutical interventions against POLO-2 kinase.

  20. Glucagon and cAMP inhibit cholesterol 7alpha-hydroxylase (CYP7A1) gene expression in human hepatocytes: discordant regulation of bile acid synthesis and gluconeogenesis.

    Science.gov (United States)

    Song, Kwang-Hoon; Chiang, John Y L

    2006-01-01

    The gene encoding cholesterol 7alpha-hydroxylase (CYP7A1) is tightly regulated to control bile acid synthesis and maintain lipid homeostasis. Recent studies in mice suggest that bile acid synthesis is regulated by the fasted-to-fed cycle, and fasting induces CYP7A1 gene expression in parallel to the induction of peroxisome proliferators-activated receptor gamma co-activator 1alpha (PGC-1alpha) and phosphoenolpyruvate carboxykinase (PEPCK). How glucagon regulates CYP7A1 gene expression in the human liver is not clear. Here we show that glucagon and cyclic adenosine monophosphate (cAMP) strongly repressed CYP7A1 mRNA expression in human primary hepatocytes. Reporter assays confirmed that cAMP and protein kinase A (PKA) inhibited human CYP7A1 gene transcription, in contrast to their stimulation of the PEPCK gene. Mutagenesis analysis identified a PKA-responsive region located within the previously identified HNF4alpha binding site in the human CYP7A1 promoter. Glucagon and cAMP increased HNF4alpha phosphorylation and reduced the amount of HNF4alpha present in CYP7A1 chromatin. Our findings suggest that glucagon inhibited CYP7A1 gene expression via PKA phosphorylation of HNF4alpha, which lost its ability to bind the CYP7A1 gene and resulted in inhibition of human CYP7A1 gene transcription. In conclusion, this study unveils a species difference in nutrient regulation of the human and mouse CYP7A1 gene and suggests a discordant regulation of bile acid synthesis and gluconeogenesis by glucagon in human livers during fasting.

  1. [Possible significance of prostaglandins in the pathogenesis of Crohn's disease].

    Science.gov (United States)

    Schmidt, E; Bruch, H P; Walter, K

    1977-04-01

    Prostaglandins (E1, E2, F2alpha) produce and intensify peristaltic contractions in the healthy human intestinal muscle system according to dosage (threshold I-10(-4) microng/ml--maximum effective concentration 1 microng/ml). By subsequent introduction of adrenaline, the intestinal muscle system activated by prostaglandines can be completely relaxed again. Intestinal muscles from patients with Crohn's disease show a marked deviation from this behaviour: 1. The intestinal muscle system is extremely sensitive to prostagladins: maximum concentrations are already reached by about a thousand times smaller concentration than in the intestines. 2. The dose of adrenaline does not lead to dialtion, which is usual, but to contraction of the muscle system. These changes in the contractility of the intestine can explain some components of the clinical symptomatology of Crohn's disease.

  2. 1. cap alpha. ,25-Dihydroxyvitamin D/sub 3/ inhibits. gamma. -interferon synthesis by normal human peripheral blood lymphocytes

    Energy Technology Data Exchange (ETDEWEB)

    Reichel, H.; Koeffler, H.P.; Tobler, A.; Norman, A.W.

    1987-05-01

    1..cap alpha..,25-Dihydroxyvitamin D/sub 3/ (1,25-(OH)/sub 2/D/sub 3/), the biologically active metabolite of vitamin D/sub 3/, inhibited synthesis of ..gamma..-interferon (IFN-..gamma..) by phytohemagglutinin-activated peripheral blood lymphocytes (PBLs). A significant reduction of IFN-..gamma.. protein levels in PBL culture medium was achieved with a physiologic 1,25-(OH)/sub 2/D/sub 3/ concentration, 1,25-(OH)/sub 2/D/sub 3/ also inhibited accumulation of IFN-..gamma.. mRNA in activated PBLs in a dose-dependent fashion. The ability of 1,25-(OH)/sub 2/D/sub 3/ to modulate IFN-..gamma.. protein synthesis was unaltered in the presence of high concentrations of recombinant human interleukin 2. The suppression of IFN-..gamma.. synthesis by PBLs was specific for 1,25-(OH)/sub 2/D/sub 3/; the potencies of other vitamin D/sub 3/ metabolites were correlated with their affinities for the cellular 1,25-(OH)/sub 2/D/sub 3/ receptor. The time course of 1,25-(OH)/sub 2/D/sub 3/ receptor expression in phytohemagglutinin-activated PBLs was correlated with the time course of 1,25-(OH)/sub 2/D/sub 3/-mediated inhibition of IFN-..gamma.. synthesis. Finally, the authors examined the effects of 1,25-(OH)/sub 2/D/sub 3/ on the constitutive IFN-..gamma.. production by two human T-lymphocyte lines transformed by human T-lymphotropic virus type I. The cell lines were established from a normal donor (cell line S-LB1) and from a patient with vitamin D-dependent rickets type 2 (cell line Ab-VDR). IFN-..gamma.. synthesis by S-LB1 cells was inhibited in a dose-dependent fashion by 1,25-(OH)/sub 2/D/sub 3/, whereas IFN-..gamma.. synthesis by Ab-VDR cells was not altered by 1,25-(OH)/sub 2/D/sub 3/. The data presented in this study provide evidence for a role of 1,25-(OH)/sub 2/D/sub 3/ in immunoregulation.

  3. Effect of Lipo-prostaglandin E1on Mesangial Proliferative Glomerulonephritis in Rats

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    The antinephritic effect of lipo-prostaglandin E1, prostaglandin E1 incorporated in lipid microspheres was investigated using an experimental model of mesangial proliferative glomerulonephritis (MsPGN). Twenty-two female rats were randomly divided into nephritic group (N, n= 6),lipo-prostaglandin E1 treated group (NL, n = 8) and control group (C, n = 6). Lipo-prostaglandin E1 was given intravenously at 40 μg · kg-1 · d-1 from the 6th week to the 8th week. Twenty-four h urinary protein contents and blood creatinine (Cr) were determined and the pathological changes were observed in the experiment. The expression of proliferating cell nuclear antigen (PCNA), extracellular matrix (fibronectin, FN; collagen type Ⅳ, Col Ⅳ) and transforming growth factor β1(TGFβ1) was detected by using immunohistochemistry. The results showed that lipo-prostaglandin E1 significantly inhibited the glomerular histopathological changes as well as the elevation of plasma Cr (P<0.05). The overexpression of PCNA, FN, Col Ⅳ and TGFβ1 were also obviously inhibited in group NL as compared with the group N (P<0.01). It was suggested that lipo-prostaglandin E1could improve renal function, inhibit the proliferation of glomerular cells and reduce the deposition of extracellular matrix, which may be related to the down-regulation of the TGFβ1 expression.

  4. Monoclonal Antibodies Targeting the Alpha-Exosite of Botulinum Neurotoxin Serotype/A Inhibit Catalytic Activity.

    Directory of Open Access Journals (Sweden)

    Yongfeng Fan

    Full Text Available The paralytic disease botulism is caused by botulinum neurotoxins (BoNT, multi-domain proteins containing a zinc endopeptidase that cleaves the cognate SNARE protein, thereby blocking acetylcholine neurotransmitter release. Antitoxins currently used to treat botulism neutralize circulating BoNT but cannot enter, bind to or neutralize BoNT that has already entered the neuron. The light chain endopeptidase domain (LC of BoNT serotype A (BoNT/A was targeted for generation of monoclonal antibodies (mAbs that could reverse paralysis resulting from intoxication by BoNT/A. Single-chain variable fragment (scFv libraries from immunized humans and mice were displayed on the surface of yeast, and 19 BoNT/A LC-specific mAbs were isolated by using fluorescence-activated cell sorting (FACS. Affinities of the mAbs for BoNT/A LC ranged from a KD value of 9.0×10-11 M to 3.53×10-8 M (mean KD 5.38×10-9 M and median KD 1.53×10-9 M, as determined by flow cytometry analysis. Eleven mAbs inhibited BoNT/A LC catalytic activity with IC50 values ranging from 8.3 ~73×10-9 M. The fine epitopes of selected mAbs were also mapped by alanine-scanning mutagenesis, revealing that the inhibitory mAbs bound the α-exosite region remote from the BoNT/A LC catalytic center. The results provide mAbs that could prove useful for intracellular reversal of paralysis post-intoxication and further define epitopes that could be targeted by small molecule inhibitors.

  5. Alpha-ketoglutarate inhibits glutamine degradation and enhances protein synthesis in intestinal porcine epithelial cells.

    Science.gov (United States)

    Yao, Kang; Yin, Yulong; Li, Xilong; Xi, Pengbin; Wang, Junjun; Lei, Jian; Hou, Yongqing; Wu, Guoyao

    2012-06-01

    α-Ketoglutarate (AKG) is a key intermediate in glutamine metabolism. Emerging evidence shows beneficial effects of AKG on clinical and experimental nutrition, particularly with respect to intestinal growth and integrity. However, the underlying mechanisms are unknown. Intestinal porcine epithelial cells (IPEC-1) were used to test the hypothesis that AKG inhibits glutamine degradation and enhances protein synthesis. IPEC-1 cells were cultured for 3 days in Dulbecco's modified Eagle's-F12 Ham medium (DMEM-F12) containing 0, 0.2, 0.5 or 2 mM of AKG. At the end of the 3-day culture, cells were used to determine L-[U-14C]glutamine utilization, protein concentration, protein synthesis, and the total and phosphorylated levels of the mammalian target of the rapamycin (mTOR), ribosomal protein S6 kinase-1 (S6K1) and eukaryotic initiation factor (eIF) 4E-binding protein-1 (4E-BP1). Compared with 0 mM of AKG (control), 0.2 and 0.5 mM of AKG dose-dependently reduced (P<0.05) glutamine degradation and the production of glutamate, alanine and aspartate in IPEC-1 cells. Addition of 0.5 and 2 mM of AKG to culture medium enhanced protein synthesis (P<0.05) by 78 and 101% without affecting protein degradation, compared to the control group. Rapamycin (50 nM; a potent inhibitor of mTOR) attenuated the stimulatory effect of AKG on protein synthesis. Consistent with these metabolic data, the addition of 0.5 or 2 mM of AKG to culture medium increased (P<0.05) the phosphorylated levels of mTOR, S6k1 and 4E-BP1 proteins. Collectively, these results indicate that AKG can spare glutamine and activate the mTOR signaling pathway to stimulate protein synthesis in intestinal epithelial cells.

  6. Macrophage inflammatory protein 1alpha inhibits postentry steps of human immunodeficiency virus type 1 infection via suppression of intracellular cyclic AMP.

    Science.gov (United States)

    Amella, Carol-Ann; Sherry, Barbara; Shepp, David H; Schmidtmayerova, Helena

    2005-05-01

    Primary isolates of human immunodeficiency virus type 1 (HIV-1) predominantly use chemokine receptor CCR5 to enter target cells. The natural ligands of CCR5, the beta-chemokines macrophage inflammatory protein 1alpha (MIP-1alpha), MIP-1beta, and RANTES, interfere with HIV-1 binding to CCR5 receptors and decrease the amount of virions entering cells. Although the inhibition of HIV-1 entry by beta-chemokines is well documented, their effects on postentry steps of the viral life cycle and on host cell components that control the outcome of infection after viral entry are not well defined. Here, we show that all three beta-chemokines, and MIP-1alpha in particular, inhibit postentry steps of the HIV-1 life cycle in primary lymphocytes, presumably via suppression of intracellular levels of cyclic AMP (cAMP). Productive HIV-1 infection of primary lymphocytes requires cellular activation. Cell activation increases intracellular cAMP, which is required for efficient synthesis of proviral DNA during early steps of viral infection. Binding of MIP-1alpha to cognate receptors decreases activation-induced intracellular cAMP levels through the activation of inhibitory G proteins. Furthermore, inhibition of one of the downstream targets of cAMP, cAMP-dependent PKA, significantly inhibits synthesis of HIV-1-specific DNA without affecting virus entry. These data reveal that beta-chemokine-mediated inhibition of virus replication in primary lymphocytes combines inhibitory effects at the entry and postentry levels and imply the involvement of beta-chemokine-induced signaling in postentry inhibition of HIV-1 infection.

  7. Prostaglandin E2 negatively regulates AMP-activated protein kinase via protein kinase A signaling pathway.

    Science.gov (United States)

    Funahashi, Koji; Cao, Xia; Yamauchi, Masako; Kozaki, Yasuko; Ishiguro, Naoki; Kambe, Fukushi

    2009-01-01

    We investigated possible involvement of prostaglandin (PG) E2 in regulation of AMP-activated protein kinase (AMPK). When osteoblastic MG63 cells were cultured in serum-deprived media, Thr-172 phosphorylation of AMPK alpha-subunit was markedly increased. Treatment of the cells with PGE2 significantly reduced the phosphorylation. Ser-79 phosphorylation of acetyl-CoA carboxylase, a direct target for AMPK, was also reduced by PGE2. On the other hand, PGE2 reciprocally increased Ser-485 phosphorylation of the alpha-subunit that could be associated with inhibition of AMPK activity. These effects of PGE2 were mimicked by PGE2 receptor EP2 and EP4 agonists and forskolin, but not by EP1 and EP3 agonists, and the effects were suppressed by an adenylate cyclase inhibitor SQ22536 and a protein kinase A inhibitor H89. Additionally, the PGE2 effects were duplicated in primary calvarial osteoblasts. Together, the present study demonstrates that PGE2 negatively regulates AMPK activity via activation of protein kinase A signaling pathway.

  8. Prostaglandin I2 and Prostaglandin E2 Modulate Human Intrarenal Artery Contractility Through Prostaglandin E2-EP4, Prostacyclin-IP, and Thromboxane A2-TP Receptors

    DEFF Research Database (Denmark)

    Eskildsen, Morten P; Hansen, Pernille B L; Stubbe, Jane

    2014-01-01

    receptors. Intrarenal arteries were microdissected from human nephrectomy samples (n=53, median diameter ≈362 μm, 88% viable, 76% relaxed in response to acetylcholine). Rings were suspended in myographs to record force development. In vessels with K(+)-induced tension (EC70: -log [mol/L]=1.36±0.03), PGE2....../L elicited increased tension. This was abolished by thromboxane receptor (TP) antagonist (S18886, 10(-6) mol/L). A TP agonist (U46619, n=6) evoked tension (EC50=8.1±0.2) that was inhibited by S18886. Polymerase chain reaction and immunoblotting showed EP4, IP, and TP receptors in intrarenal arteries......Cyclooxygenase inhibitors decrease renal blood flow in settings with decreased effective circulating volume. The present study examined the hypothesis that prostaglandins, prostaglandin E2 (PGE2) and prostacyclin (PGI2), induce relaxation of human intrarenal arteries through PGE2-EP and PGI2-IP...

  9. Compartmentalization of prostaglandins in the canine kidney

    Energy Technology Data Exchange (ETDEWEB)

    Morgan-Boyd, R.L.

    1986-01-01

    The kidney has been shown to synthesize all of the naturally occurring major prostaglandins which may be restricted to a discrete part of the kidney where their actions are physiologically important, such as the vascular compartment and the tubular compartment. In order to examine this concept of compartmentalization, the authors conducted a series of experiments to determine whether PGl/sub 2/, measured as 6-keto-pGF/sub 1..cap alpha../, produced in the kidney is restricted to the renal vascular compartment or whether it also has access to the tubular compartment. Experiments were performed in the pentobarbital-anesthetized dog. Increasing pre-glomerular levels of 6-keto-PFG/sub 1..cap alpha../ caused marked increases in both the urinary excretion and the renal venous outflow to 6-keto-PGF/sub 1..cap alpha../. When /sup 3/H-6-keto-PGF/sub 1..cap alpha../ was co-infused with inulin into the renal artery, 33% of the radioactivity and 23% of the inulin was recovered on first pass. With infusion of /sup 3/H-PGl/sub 2/ and inulin, 20% of the radioactivity and 28% of the inulin reached the urine on first pass. Radioactive PGl/sub 2/ appeared to be less filterable at the glomeruli than either /sup 3/H-6-keto-PGF/sub 1..cap alpha../ or inulin. In the final set of experiments, in which dogs were prepared for a ureteral stopped-flow study, the PGE/sub 2//U/P/sub In/ ratio a peak was observed proximal to the Na/sup +/ plateau but distal to the Na+ nadir. In light of the results from the stopped-flow study and the intrarenal infusion studies, they conclude that PGE/sub 2/ synthesized in the kidney enters both the renal and tubular compartments. In contrast, they find that 6-keto-PGF/sub 1..cap alpha../ of renal origin enters only the renal origin enters only the renal vascular compartment and not the tubular compartment.

  10. Eukaryotic translation elongation factor 1-alpha 1 inhibits p53 and p73 dependent apoptosis and chemotherapy sensitivity.

    Directory of Open Access Journals (Sweden)

    Alvaro Blanch

    Full Text Available The p53 family of transcription factors is a key regulator of cell proliferation and death. In this report we identify the eukaryotic translation elongation factor 1-alpha 1 (eEF1A1 to be a novel p53 and p73 interacting protein. Previous studies have demonstrated that eEF1A1 has translation-independent roles in cancer. We report that overexpression of eEF1A1 specifically inhibits p53-, p73- and chemotherapy-induced apoptosis resulting in chemoresistance. Short-interfering RNA-mediated silencing of eEF1A1 increases chemosensitivity in cell lines bearing wild type p53, but not in p53 null cells. Furthermore, silencing of eEF1A1 partially rescues the chemoresistance observed in response to p53 or p73 knockdown, suggesting that eEF1A1 is a negative regulator of the pro-apoptotic function of p53 and p73. Thus, in the context of p53-family signaling, eEF1A1 has anti-apoptotic properties. These findings identify a novel mechanism of regulation of the p53 family of proteins by eEF1A1 providing additional insight into potential targets to sensitize tumors to chemotherapy.

  11. Overexpression of cellular repressor of E1A-stimulated genes inhibits TNF-{alpha}-induced apoptosis via NF-{kappa}B in mesenchymal stem cells

    Energy Technology Data Exchange (ETDEWEB)

    Peng, Cheng-Fei [Xijing Hospital, Fourth Military Medical University, Xi' an (China); Cardiovascular Research Institute and Department of Cardiology, Shenyang Northern Hospital, Shenyang (China); Han, Ya-Ling, E-mail: hanyaling53@gmail.com [Cardiovascular Research Institute and Department of Cardiology, Shenyang Northern Hospital, Shenyang (China); Jie-Deng,; Yan, Cheng-Hui; Jian-Kang,; Bo-Luan,; Jie-Li [Cardiovascular Research Institute and Department of Cardiology, Shenyang Northern Hospital, Shenyang (China)

    2011-03-25

    Research highlights: {yields} CREG protected MSCs from tumor necrosis factor-{alpha} (TNF-{alpha}) induced apoptosis. {yields} CREG inhibits the phosphorylation of I{kappa}B{alpha} and prevents the activation of NF-{kappa}B. {yields} CREG inhibits NF-{kappa}B nuclear translocation and pro-apoptosis protein transcription. {yields} CREG anti-apoptotic effect involves inhibition of the death receptor pathway. {yields} p53 is downregulated by CREG via NF-{kappa}B pathway under TNF-{alpha} stimulation. -- Abstract: Bone marrow-derived mesenchymal stem cells (MSCs) show great potential for therapeutic repair after myocardial infarction. However, poor viability of transplanted MSCs in the ischemic heart has limited their use. Cellular repressor of E1A-stimulated genes (CREG) has been identified as a potent inhibitor of apoptosis. This study therefore aimed to determine if rat bone marrow MSCs transfected with CREG-were able to effectively resist apoptosis induced by inflammatory mediators, and to demonstrate the mechanism of CREG action. Apoptosis was determined by flow cytometric and terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end-labeling assays. The pathways mediating these apoptotic effects were investigated by Western blotting. Overexpression of CREG markedly protected MSCs from tumor necrosis factor-{alpha} (TNF-{alpha}) induced apoptosis by 50% after 10 h, through inhibition of the death-receptor-mediated apoptotic pathway, leading to attenuation of caspase-8 and caspase-3. Moreover, CREG resisted the serine phosphorylation of I{kappa}B{alpha} and prevented the nuclear translocation of the transcription factor nuclear factor-{kappa}B (NF-{kappa}B) under TNF-{alpha} stimulation. Treatment of cells with the NF-{kappa}B inhibitor pyrrolidine dithiocarbamate (PDTC) significantly increased the transcription of pro-apoptosis proteins (p53 and Fas) by NF-{kappa}B, and attenuated the anti-apoptotic effects of CREG on MSCs. The results of this study

  12. Tricyclic isoxazolines: identification of R226161 as a potential new antidepressant that combines potent serotonin reuptake inhibition and alpha2-adrenoceptor antagonism.

    Science.gov (United States)

    Andrés, J Ignacio; Alcázar, Jesús; Alonso, José M; Alvarez, Rosa M; Bakker, Margot H; Biesmans, Ilse; Cid, José M; De Lucas, Ana I; Drinkenburg, Wilhelmus; Fernández, Javier; Font, Luis M; Iturrino, Laura; Langlois, Xavier; Lenaerts, Ilse; Martínez, Sonia; Megens, Anton A; Pastor, Joaquín; Pullan, Shirley; Steckler, Thomas

    2007-06-01

    In previous articles we have described the discovery of a new series of tricyclic isoxazolines combining central serotonin (5-HT) reuptake inhibition with alpha(2)-adrenoceptor antagonistic activity. We report now on the synthesis, the in vitro binding potency and the primary in vivo activity of six enantiomers within this series, one of which was selected for further pharmacological evaluation and assigned as R226161. Some additional in vivo studies in rats are described with this compound, which proved to be centrally and orally active as a combined 5-HT reuptake inhibitor and alpha(2)-adrenoceptor antagonist.

  13. Direct bone formation during distraction osteogenesis does not require TNF alpha receptors and elevated serum TNF alpha fails to inhibit bone formation in TNFR1 deficient mice

    Science.gov (United States)

    Distraction osteogenesis (DO) is a process which induces direct new bone formation as a result of mechanical distraction. Tumor necrosis factor-alpha (TNF) is a cytokine that can modulate osteoblastogenesis. The direct effects of TNF on direct bone formation in rodents are hypothetically mediated th...

  14. Prostaglandins, catecholamines, renin and aldosterone during hypertensive and normotensive pregnancy.

    Science.gov (United States)

    Pedersen, E B; Christensen, N J; Christensen, P; Johannesen, P; Kornerup, H J; Kristensen, S; Lauritsen, J G; Leyssac, P P; Rasmussen, A B; Wohlert, M

    1982-01-01

    Urinary excretion of prostaglandin E2 (PGE2) and F2 alpha (PGF2 alpha), plasma concentrations of renin (PRC), aldosterone (PAC), noradrenaline (PNA) and adrenaline (PA) were determined in the third trimester of pregnancy, 5 days and 3 months after delivery in preeclampsia and normotensive pregnant and non-pregnant control subjects. PGE2 was higher in pregnant control subjects than in non-pregnant subjects, but reduced to non-pregnant level in preeclampsia. PGF2 alpha was the same in preeclampsia and normotensive pregnancy but higher than in the non-pregnant group. PRC and PAC were increased during pregnancy, but considerably lesser in preeclampsia than during normotensive pregnancy. PNA and PA were the same in all three groups. All parameters were normal 3 months after delivery. There were no correlations between any of the hormones and blood pressure in any of the groups. PGE2 was positively correlated to PRC. The lack of renal PGE2 in preeclampsia might be responsible for the decrease in renal blood flow and sodium excretion, and the changes in PRC and PAC are supposed to be secondary to changes in PGE2. It is hypothesised that preeclampsia is a state of prostaglandin deficiency.

  15. Prostaglandin production by rat vaginal tissue, in vitro, in response to ethanol, a mild mucosal irritant.

    Science.gov (United States)

    Dubin, N H; Wolff, M C; Thomas, C L; DiBlasi, M C

    1985-05-01

    Toxicological testing of vaginal irritants currently involves in vivo testing in rabbits. While chemical-induced irritation or inflammation involves numerous biologic responses, these responses appear to be to a large extent mediated by prostaglandin release. Since vaginal tissue of the rat produces prostaglandins, this tissue was studied in vitro to determine if it would respond to ethanol, a mild irritant. Small vaginal segments were rinsed in Krebs-Ringer bicarbonate buffer (pH 7.0) and exposed to various concentrations of ethanol. The segments were then transferred to fresh buffer and incubated for 30 min in a shaking 37 degrees C water bath. Ethanol (70%) exposure for 30 sec increased prostaglandin E2 and F2 alpha production by vaginal tissue. While ethanol exposure resulted in increases in prostaglandin production regardless of the stage of the cycle from which the tissue was derived, the relative increase was greatest in tissues from the diestrous stage of the cycle. The prostaglandin production response of vaginal tissue, and of cervical and uterine tissue, was related to the concentration of ethanol to which these tissues were exposed. Indomethacin blocked this response in a dose-dependent manner. These experiments demonstrate that vaginal tissue responds to ethanol by increasing production of PGF2 alpha and PGE2. This in vitro system may prove useful as an alternative to live-animal testing in the screening of irritants of the vaginal mucosa or other tissues as well.

  16. Role of mucosal prostaglandins and DNA synthesis in gastric cytoprotection by luminal epidermal growth factor.

    Science.gov (United States)

    Konturek, S J; Brzozowski, T; Piastucki, I; Dembinski, A; Radecki, T; Dembinska-Kiec, A; Zmuda, A; Gregory, H

    1981-01-01

    This study compares the effect of epidermal growth factor and prostaglandins (PGE2 or PGI2), applied topically to gastric mucosa, on gastric secretion and formation of ASA-induced gastric ulcerations in rats. Epidermal growth factor given topically in non-antisecretory doses prevented dose-dependently the formation of ASA-induced ulcers without affecting prostaglandin generation but with a significant rise in DNA synthesis in the oxyntic mucosa. The anti-ulcer effect of topical prostaglandins was also accompanied by an increase in DNA synthesis. This study indicates that topical epidermal growth factor, like PGE2 or PGI2, is cytoprotective and that this cytoprotection is not mediated by the inhibition of gastric secretion or prostaglandin formation but related to the increase in DNA synthesis in oxyntic mucosa. PMID:7030877

  17. Changes in the Th1 : Th2 Cytokine Bias in Pregnancy and the Effects of the Anti-Inflammatory Cyclopentenone Prostaglandin 15-Deoxy-Δ12,14-Prostaglandin J2

    Directory of Open Access Journals (Sweden)

    Lynne Sykes

    2012-01-01

    Full Text Available Pregnancy is a complex immunological state in which a bias towards T helper 2 (Th2 protects the fetus. Evidence suggests that proinflammatory cytokines increase the risk of poor neonatal outcome, independently of the direct effect of preterm labour. The anti-inflammatory prostaglandin 15-deoxy-Δ12,14-Prostaglandin J2 (15dPGJ2 inhibits nuclear factor Kappa B (NF-κB in amniocytes and myocytes in vitro and is a ligand for the chemoattractant receptor-homologous molecule expressed on Th2 cells (CRTH2 receptor. Here we examine the Th1:Th2 cytokine bias in pregnancy and whether 15dPGJ2 could be used to inhibit the production of the proinflammatory cytokines through inhibition of NF-κB while simultaneously promoting Th2 interleukin 4 (IL-4 synthesis via CRTH2 in T helper cells. Peripheral blood mononuclear cells (PBMCs from women at 28 weeks, term pre-labour, term labour as well as non-pregnant female controls were cultured with 15dPGJ2 or vehicle control and stimulated with phorbol myristyl acetate (PMA/ionomycin. The percentage of CD4+ cells producing interferon gamma (IFN-γ and tumor necrosis factor alpha (TNF-α in response to PMA/ionomycin was significantly reduced in pregnancy. 15dPGJ2 reduced IFN-γ and TNF-α production in stimulated T helper cells, but did not alter IL-4 production in CRTH2+ve cells. 15dPGJ2 also reduced phospho-p65 in stimulated PBMCs. In summary, 15dPGJ2 suppresses the Th1 response of PBMCs during pregnancy and active labour whilst maintaining the Th2 response suggesting a therapeutic benefit in reducing neonatal morbidity in inflammation-induced PTL.

  18. Anti-interleukin-1 alpha autoantibodies in humans: Characterization, isotype distribution, and receptor-binding inhibition--higher frequency in Schnitzler's syndrome (urticaria and macroglobulinemia)

    Energy Technology Data Exchange (ETDEWEB)

    Saurat, J.H.; Schifferli, J.; Steiger, G.; Dayer, J.M.; Didierjean, L. (Department of Dermatology, University Hospital, Geneva (Switzerland))

    1991-08-01

    Since autoantibodies (Abs) to cytokines may modify their biologic activities, high-affinity binding factors for interleukin-1 alpha (IL-1 alpha BF) were characterized in human sera. IL-1 alpha BF was identified as IgG (1) by sucrose density-gradient centrifugation followed by immunodiffusion autoradiography, (2) by ligand-blotting method, (3) by ligand binding to affinity-immobilized serum IgG, and (4) by IgG affinity purification followed by sucrose density-gradient centrifugation. IL-1 alpha binding activity resided in the F(ab)2 fragment. The apparent equilibrium constant was in the range of IgG found after immunization with conventional antigens (i.e., 10(-9) to 10(-10) mol/L). Anti-IL-1 alpha IgG auto-Abs represented only an extremely small fraction of total IgG (less than 1/10(-5)). Some sera with IL-1 alpha BF and purified IgG thereof were able to inhibit by 96% to 98% the binding of human recombinant IL-1 alpha to its receptor on murine thymoma EL4-6.1 cells, whereas other sera did not. When 125I-labeled anti-IL-1 alpha IgG complexes were injected into rats, they prolonged the plasma half-life of 125I-labeled IL-1 alpha several fold and altered its tissue distribution. The predominant class was IgG (12/19), mainly IgG4 (9/19), but in five of the sera, anti-IL-1 alpha IgA was also detected. In a screening of 271 sera, IL-1 alpha BF was detected in 17/98 normal subjects and was not more frequent in several control groups of patients, except in patients with Schnitzler's syndrome (fever, chronic urticaria, bone pain, and monoclonal IgM paraprotein) (6/9; p less than 0.005). The pathologic significance of these auto-Abs remains to be determined.

  19. Inhibition of Peripheral TNF-α and Downregulation of Microglial Activation by Alpha-Lipoic Acid and Etanercept Protect Rat Brain Against Ischemic Stroke.

    Science.gov (United States)

    Wu, Ming-Hsiu; Huang, Chao-Ching; Chio, Chung-Ching; Tsai, Kuen-Jer; Chang, Ching-Ping; Lin, Nan-Kai; Lin, Mao-Tsun

    2016-09-01

    Ischemic stroke, caused by obstruction of blood flow to the brain, would initiate microglia activation which contributes to neuronal damage. Therefore, inhibition of microglia-mediated neuroinflammation could be a therapeutic strategy for ischemic stroke. This study was aimed to elucidate the anti-inflammatory effects of alpha-lipoic acid and etanercept given either singly or in combination in rats subjected to middle cerebral artery occlusion. Both α-lipoic acid and etanercept markedly reduced cerebral infarct, blood-brain barrier disruption, and neurological motor deficits with the former drug being more effective with the dosage used. Furthermore, when used in combination, the reduction was more substantial. Remarkably, a greater diminution in the serum levels of tumor necrosis factor-alpha as well as the brain levels of microglial activation (e.g., microgliosis, amoeboid microglia, and microglial overexpression of tumor necrosis factor-α) was observed with the combined drug treatment as compared to the drugs given separately. We conclude that inhibition of peripheral tumor necrosis factor-alpha as well as downregulation of brain microglial activation by alpha-lipoic acid or etanercept protect rat brain against ischemic stroke. Moreover, when both drugs were used in combination, the stroke recovery was promoted more extensively.

  20. Identification of a novel compound that inhibits iNOS and COX-2 expression in LPS-stimulated macrophages from Schisandra chinensis.

    Science.gov (United States)

    Lee, You Jin; Park, Sun Young; Kim, Sun Gun; Park, Da Jung; Kang, Jum Soon; Lee, Sang Joon; Yoon, Sik; Kim, Young Hun; Bae, Yoe-Sik; Choi, Young-Whan

    2010-01-22

    A novel alpha-iso-cubebenol, which has anti-inflammatory effects in lipopolysaccharide (LPS)-treated RAW 264.7 macrophages, was isolated from the fruits of Schisandra chinensis. alpha-iso-cubebenolinhibited LPS-induced nitric oxide (NO) and prostaglandin E(2) (PGE(2)) production. Consistent with these findings, alpha-iso-cubebenol also reduced the LPS-induced expression of inducible nitric oxide synthase and cyclooxygenase-2 at the protein and mRNA levels in a concentration-dependent manner. alpha-iso-cubebenol also inhibited LPS-induced nuclear translocation of the NF-kappaB p65 subunit. Furthermore, alpha-iso-cubebenol suppressed the phosphorylation of ERK, JNK, and p38 kinase induced by LPS. Since the novel alpha-iso-cubebenol blocked the production of several pro-inflammatory mediators induced by LPS in macrophages, the molecule can be useful material for the development of anti-inflammatory agents against bacterial infections or endotoxin.

  1. Mechanism and clinical significance of prostaglandin-induced iris pigmentation.

    Science.gov (United States)

    Stjernschantz, Johan W; Albert, Daniel M; Hu, Dan-Ning; Drago, Filippo; Wistrand, Per J

    2002-08-01

    The new glaucoma drugs latanoprost, isopropyl unoprostone, travoprost, and bimatoprost cause increased pigmentation of the iris in some patients. The purpose of the present article is to survey the available preclinical and clinical data on prostaglandin-induced iris pigmentation and to assess the phenomenon from a clinical perspective. Most of the data have been obtained with latanoprost, and it appears that there is a predisposition to latanoprost-induced iris pigmentation in individuals with hazel or heterochromic eye color. As latanoprost and travoprost are selective agonists for the prostaglandin F(2alpha) receptor, it is likely that the phenomenon is mediated by this receptor. Several studies indicate that latanoprost stimulates melanogenesis in iridial melanocytes, and transcription of the tyrosinase gene is upregulated. The safety aspects of latanoprost-induced iris pigmentation have been addressed in histopathologic studies, and no evidence of harmful consequences of the side effect has been found. Although a final assessment of the clinical significance of prostaglandin-induced iris pigmentation currently is impossible to make, it appears that the only clear-cut disadvantage is a potential heterochromia between the eyes in unilaterally treated patients because the heterochromia is likely to be permanent, or very slowly reversible.

  2. Helenalin and 11 alpha,13-dihydrohelenalin, two constituents from Arnica montana L., inhibit human platelet function via thiol-dependent pathways.

    Science.gov (United States)

    Schröder, H; Lösche, W; Strobach, H; Leven, W; Willuhn, G; Till, U; Schrör, K

    1990-03-15

    This study investigates the effect on human platelet function of two sesquiterpene lactones from Arnica montana L., helenalin (H) and 11 alpha,13-dihydrohelenalin (DH). Both compounds inhibited collagen-induced platelet aggregation, thromboxane formation and 5-hydroxytryptamine secretion in a concentration-dependent manner at 3-300 microM. When arachidonic acid was used as stimulus, thromboxane formation remained unaffected despite of inhibition of platelet aggregation. Both H and DH reduced the number of acid-soluble sulfhydryl groups in platelets, by up to 78% at anti-aggregatory concentrations. Moreover, H- and DH-induced platelet inhibition could be prevented by the thiol containing amino acid cysteine. It is concluded that H and DH inhibit platelet function via interaction with platelet sulfhydryl groups, probably associated with reduced phospholipase A2 activity.

  3. Serine proteinase inhibition by the active site titrant N alpha-(N, N-dimethylcarbamoyl)-alpha-azaornithine p-nitrophenyl ester. A comparative study.

    Science.gov (United States)

    Ascenzi, P; Balliano, G; Gallina, C; Polticelli, F; Bolognesi, M

    2000-02-01

    Kinetics for the hydrolysis of the chromogenic active-site titrant N alpha-(N,N-dimethylcarbamoyl)-alpha-azaornithine p-nitrophenyl ester (Dmc-azaOrn-ONp) catalysed by bovine beta-trypsin, bovine alpha-thrombin, bovine Factor Xa, human alpha-thrombin, human Factor Xa, human Lys77-plasmin, human urinary kallikrein, Mr 33 000 and Mr 54 000 species of human urokinase, porcine pancreatic beta-kallikrein-A and -B and Ancrod (the coagulating serine proteinase from the Malayan pit viper Agkistrodon rhodostoma venom) have been obtained between pH 6.0 and 8.0, at 21.0 degrees C, and analysed in parallel with those for the enzymatic cleavage of N alpha-(N,N-dimethylcarbamoyl)-alpha-azalysine p-nitrophenyl ester (Dmc-azaLys-ONp). The enzyme kinetics are consistent with the minimum three-step catalytic mechanism of serine proteinases, the rate-limiting step being represented by the deacylation process. Bovine beta-trypsin kinetics are modulated by the acid-base equilibrium of the His57 catalytic residue (pKa approximately 6.9). Dmc-azaOrn-ONp and Dmc-azaLys-ONp bind stoichiometrically to the serine proteinase active site, and allow the reliable determination of the active enzyme concentration between 1.0 x 10-6 M and 3.0 x 10-4 M. The affinity and the reactivity for Dmc-azaOrn-ONp (expressed by Ks and k+2/Ks, respectively) of the serine proteinases considered are much lower than those for Dmc-azaLys-ONp. The very different affinity and reactivity properties for Dmc-azaOrn-ONp and Dmc-azaLys-ONp have been related to the different size of the ornithine/lysine side chains, and to the ensuing different positioning of the active-site titrants upon binding to the enzyme catalytic centre (i.e. to P1-S1 recognition). These data represent the first detailed comparative investigation on the catalytic properties of serine proteinases towards an ornithine derivative (i. e. Dmc-azaOrn-ONp).

  4. The transcriptional activity of hepatocyte nuclear factor 4 alpha is inhibited via phosphorylation by ERK1/2

    Science.gov (United States)

    Bacquet, Caroline; Kiss, Judit; Sipeki, Szabolcs; Martin, Ludovic; Buday, László; Bálint, Bálint L.; Arányi, Tamás

    2017-01-01

    Hepatocyte nuclear factor 4 alpha (HNF4α) nuclear receptor is a master regulator of hepatocyte development, nutrient transport and metabolism. HNF4α is regulated both at the transcriptional and post-transcriptional levels by different mechanisms. Several kinases (PKA, PKC, AMPK) were shown to phosphorylate and decrease the activity of HNF4α. Activation of the ERK1/2 signalling pathway, inducing proliferation and survival, inhibits the expression of HNF4α. However, based on our previous results we hypothesized that HNF4α is also regulated at the post-transcriptional level by ERK1/2. Here we show that ERK1/2 is capable of directly phosphorylating HNF4α in vitro at several phosphorylation sites including residues previously shown to be targeted by other kinases, as well. Furthermore, we also demonstrate that phosphorylation of HNF4α leads to a reduced trans-activational capacity of the nuclear receptor in luciferase reporter gene assay. We confirm the functional relevance of these findings by demonstrating with ChIP-qPCR experiments that 30-minute activation of ERK1/2 leads to reduced chromatin binding of HNF4α. Accordingly, we have observed decreasing but not disappearing binding of HNF4α to the target genes. In addition, 24-hour activation of the pathway further decreased HNF4α chromatin binding to specific loci in ChIP-qPCR experiments, which confirms the previous reports on the decreased expression of the HNF4a gene due to ERK1/2 activation. Our data suggest that the ERK1/2 pathway plays an important role in the regulation of HNF4α-dependent hepatic gene expression. PMID:28196117

  5. Inhibition of TNF-{alpha}-mediated inflammatory responses by a benzodioxolylacetylamino-linked benzothiazole analog in human fibroblast-like synoviocytes

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Young-Rae [Department of Biochemistry, Research Institute for Endocrine Sciences and Diabetes Research Center, Chonbuk National University Medical School, Jeonju, Jeonbuk 561-756 (Korea, Republic of); Jin, Guo Hua [College of Pharmacy, Sookmyung Women' s University, 52 Hyochangwon-gil, Yongsan-gu, Seoul 140-742 (Korea, Republic of); Lee, Sang-Myeong [Division of Biotechnology, College of Environmental and Bioresource Sciences, Chonbuk National University, Iksan, Jeonbuk 570-752 (Korea, Republic of); Park, Jin-Woo [Department of Biochemistry, Research Institute for Endocrine Sciences and Diabetes Research Center, Chonbuk National University Medical School, Jeonju, Jeonbuk 561-756 (Korea, Republic of); Ryu, Jae-Ha [College of Pharmacy, Sookmyung Women' s University, 52 Hyochangwon-gil, Yongsan-gu, Seoul 140-742 (Korea, Republic of); Jeon, Raok, E-mail: rjeon@sm.ac.kr [College of Pharmacy, Sookmyung Women' s University, 52 Hyochangwon-gil, Yongsan-gu, Seoul 140-742 (Korea, Republic of); Park, Byung-Hyun, E-mail: bhpark@jbnu.ac.kr [Department of Biochemistry, Research Institute for Endocrine Sciences and Diabetes Research Center, Chonbuk National University Medical School, Jeonju, Jeonbuk 561-756 (Korea, Republic of)

    2011-05-20

    Highlights: {yields} We synthesized SPA0537, a benzothiazole analog. {yields} SPA0537 is a potent NF-{kappa}B inhibitor. {yields} SPA0537 suppresses the production of proinflammatory mediators in human rheumatoid fibroblast-like synoviocytes. {yields} SPA0537 is effective at suppressing osteoclast differentiation. -- Abstract: The pathologic processes of rheumatoid arthritis are mediated by a number of cytokines, chemokines, and matrix metalloproteinases, the expressions of which are controlled by NF-{kappa}B. This study was performed to explore the effects of a benzothiazole analog, SPA0537, on the control of the NF-{kappa}B activation pathway. We also investigated whether SPA0537 had any anti-inflammatory effects in human rheumatoid fibroblast-like synoviocytes (FLS). SPA0537 inhibited the nuclear translocation and the DNA binding of NF-{kappa}B subunits, which correlated with the inhibitory effects on IKK phosphorylation and I{kappa}B{alpha} degradation in TNF-{alpha}-stimulated rheumatoid FLS. These events further suppressed chemokine production, matrix metalloproteinase secretion, and TNF-{alpha}-induced cell proliferation. In addition, SPA0537 inhibited the osteoclast differentiation induced by macrophage colony-stimulating factor (MCSF) and receptor activator of the NF-{kappa}B ligand (RANKL) in bone marrow macrophages. These findings suggest that SPA0537 exerts anti-inflammatory effects in rheumatoid FLS through the inhibition of the NF-{kappa}B pathway. Therefore, it may have therapeutic value for the treatment of rheumatoid arthritis.

  6. Prostaglandin E, pessaries for induction of labour.

    Science.gov (United States)

    Pearce, J M; Shepherd, J H; Sims, C D

    1979-03-17

    Vaginal pessaries containing 3 mg of prostaglandin E2 were used to induce labour in 200 patients with variable induction features. Prostaglandin-induced labour was augmented where necessary by synthetic oxytocin. There was on failed induction. Only 23% of patients with favourable induction features and 53% of patients with unfavourable features needed oxytocin. There were no adverse fetal or maternal effects. The prostaglandin E2 pessary was as effective in inducing labour as 350 microgram extra-amniotic prostaglandin E2 in tylose in a comparable group of 200 patients in which there were 4 failed inductions.

  7. Fatty Acid Amide Hydrolase (FAAH) Inhibition Enhances Memory Acquisition through Activation of PPAR-alpha Nuclear Receptors

    Science.gov (United States)

    Mazzola, Carmen; Medalie, Julie; Scherma, Maria; Panlilio, Leigh V.; Solinas, Marcello; Tanda, Gianluigi; Drago, Filippo; Cadet, Jean Lud; Goldberg, Steven R.; Yasar, Sevil

    2009-01-01

    Inhibitors of fatty acid amide hydrolase (FAAH) increase endogenous levels of anandamide (a cannabinoid CB[subscript 1]-receptor ligand) and oleoylethanolamide and palmitoylethanolamide (OEA and PEA, ligands for alpha-type peroxisome proliferator-activated nuclear receptors, PPAR-alpha) when and where they are naturally released in the brain.…

  8. Lipopolysaccharide induces expression of tumour necrosis factor alpha in rat brain : inhibition by methylprednisolone and by rolipram

    NARCIS (Netherlands)

    Buttini, M; Mir, A; Appel, K; Wiederhold, KH; Limonta, S; GebickeHaerter, PJ; Boddeke, HWGM

    1997-01-01

    1 We have investigated the effects of the phosphodiesterase (PDE) type TV inhibitor rolipram and of the glucocorticoid methylprednisolone on the induction of tumour necrosis factor alpha (TNF-alpha) mRNA and protein in brains of rats after peripheral administration of lipopolysaccharide (LPS). 2 Aft

  9. The effect of progesterone on oxytocin-stimulated intracellular Ca2+ mobilisation and prostaglandin secretion in porcine endometrium.

    Science.gov (United States)

    Kotwica, G; Oponowicz, A; Kurowicka, B; Franczak, A; Bogacka, I

    2010-01-01

    We have studied in the porcine endometrium the expression of oxytocin receptor (OTR) mRNA and the effect of progesterone (P4) on oxytocin/oxytocin receptor (OT/OTR) function concerning intracellular Ca2+ mobilisation ([Ca2+]i), prostaglandin F2alpha (PGF2alpha) and E2 (PGE2; PG) secretion. Tissue was taken from cyclic and early pregnant pigs (days 14-16). A higher expression of OTR mRNA (P < 0.05) was observed in the endometrium of cyclic than pregnant pigs. The stimulatory (P < 0.05) effect of OT (10(-7) M) on [Ca2+]i mobilisation was noticed within 15-60 s and 30-60 s in endometrial stromal cells of cyclic and pregnant pigs, respectively. In the presence of P4 (10(-5) M) basal and OT-stimulated [Ca2+]i concentrations decreased in stromal cells during luteolysis and pregnancy. In stromal cells P4 delayed mobilisation of [Ca2+]i in response to OT by 15 s during luteolysis and had no effect during pregnancy. In cyclic and pregnant epithelial cells OT stimulated mobilisation of [Ca2+]i in 45 s and 60 s, respectively. Oxytocin increased (P < 0.05) PGF2alpha secretion during luteolysis and pregnancy and PGE2 during luteolysis from endometrial slices. Progesterone did not inhibit this stimulatory effect. During luteolysis OT increased (P < 0.05) PGF2alpha in epithelial and stromal cells and PGE2 secretion in epithelial cells. In the presence of P4 this effect of OT was reduced only in stromal cyclic cells (6 h culture). The presence of P4 decreased the effect of OT on [Ca2+]i mobilisation only in stromal cells. We found that, in most conditions, P4 did not inhibit the OT-stimulated secretion of PG in the porcine endometrium.

  10. Prostaglandin Hsynthase immunoreactivity in human gut. An immunohistochemical study

    DEFF Research Database (Denmark)

    Mikkelsen, Hanne Birte; Rumessen, Jüri Johannes; Qvortrup, Klaus

    1991-01-01

    Anatomy, prostaglandin H-synthase, smooth muscle cells, intestine, muscularis externa, immunohistochemistry......Anatomy, prostaglandin H-synthase, smooth muscle cells, intestine, muscularis externa, immunohistochemistry...

  11. Comparative study of antiinflammatory drugs and sulphasalazine in relation to prostaglandin E and 19 hydroxylated prostaglandin E levels and human male fertility.

    Science.gov (United States)

    Freixa, R; Roselló Catafau, J; Gelpí, E; Iglesias Cortit, J L; Ballescá, J L; de Paz, J L; Iglesias Guiu, J; Gonzalez Merlo, J; Puig Parellada, P

    1984-12-01

    The effect of lysine salicylate, flurbiprofen and sulphasalazine on human seminal prostaglandin profiles of six normal individuals was studied. All of them were treated with pharmacological doses of the three agents for four days with rest periods of eighteen days in between. Sulphasalazine produced less prostaglandin (PG) inhibition relative to the other two antiinflammatory drugs but in contrast only sulphasalazine induced sperm changes. Infertility status associated with the ingestion of therapeutic levels of sulphasalaziane is not directly related to the endogenous PGEs and 19-OH PGEs, the major prostanoids in human semen. PG determinations were carried out using gas chromatographic (GC) techniques.

  12. Ovarian, hormonal, and reproductive events associated with synchronization of ovulation and timed appointment breeding of Bos indicus-influenced cattle using intravaginal progesterone, gonadotropin-releasing hormone, and prostaglandin F2alpha.

    Science.gov (United States)

    Saldarriaga, J P; Cooper, D A; Cartmill, J A; Zuluaga, J F; Stanko, R L; Williams, G L

    2007-01-01

    The objectives of this study were to 1) compare cumulative pregnancy rates in a traditional management (TM) scheme with those using a synchronization of ovulation protocol (CO-Synch + CIDR) for timed AI (TAI) in Bos indicus-influenced cattle; 2) evaluate ovarian and hormonal events associated with CO-Synch + CIDR and CO-Synch without CIDR; and 3) determine estrual and ovulatory distributions in cattle synchronized with Select-Synch + CIDR. The CO-Synch + CIDR regimen included insertion of a controlled internal drug-releasing device (CIDR) and an injection of GnRH (GnRH-1) on d 0, removal of the CIDR and injection of PGF2alpha (PGF) on d 7, and injection of GnRH (GnRH-2) and TAI 48 h later. For Exp. 1, predominantly Brahman x Hereford (F1) and Brangus females (n = 335) were stratified by BCS, parity, and day postpartum (parous females) before random assignment to CO-Synch + CIDR or TM. To maximize the number of observations related to TAI conception rate (n = 266), an additional 96 females in which TM controls were not available for comparison also received CO-Synch + CIDR. Conception rates to TAI averaged 39 +/- 3% and were not affected by location, year, parity, AI sire, or AI technician. Cumulative pregnancy rates were greater (P breeding season in CO-Synch + CIDR (74.1 and 95.9%) compared with TM (61.8 and 89.7%). In Exp. 2, postpartum Brahman x Hereford (F1) cows (n = 100) were stratified as in Exp. 1 and divided into 4 replicates of 25. Within each replicate, approximately one-half (12 to 13) received CO-Synch + CIDR, and the other half received CO-Synch only (no CIDR). No differences were observed between treatments, and the data were pooled. Percentages of cows ovulating to GnRH-1, developing a synchronized follicular wave, exhibiting luteal regression to PGF, and ovulating to GnRH-2 were 40 +/- 5, 60 +/- 5, 93 +/- 2, and 72 +/- 4%, respectively. In Exp. 3, primiparous Brahman x Hereford, (F1) heifers (n = 32) and pluriparous cows (n = 18) received the

  13. Delta, theta, and alpha event-related oscillations in alcoholics during Go/NoGo task: Neurocognitive deficits in execution, inhibition, and attention processing.

    Science.gov (United States)

    Pandey, Ashwini K; Kamarajan, Chella; Manz, Niklas; Chorlian, David B; Stimus, Arthur; Porjesz, Bernice

    2016-02-01

    Higher impulsivity observed in alcoholics is thought to be due to neurocognitive functional deficits involving impaired inhibition in several brain regions and/or neuronal circuits. Event-related oscillations (EROs) offer time-frequency measure of brain rhythms during perceptual and cognitive processing, which provide a detailed view of neuroelectric oscillatory responses to external/internal events. The present study examines evoked power (temporally locked to events) of oscillatory brain signals in alcoholics during an equal probability Go/NoGo task, assessing their functional relevance in execution and inhibition of a motor response. The current study hypothesized that increases in the power of slow frequency bands and their topographical distribution is associated with tasks that have increased cognitive demands, such as the execution and inhibition of a motor response. Therefore, it is hypothesized that alcoholics would show lower spectral power in their topographical densities compared to controls. The sample consisted of 20 right-handed abstinent alcoholic males and 20 age and gender-matched healthy controls. Evoked delta (1.0-3.5Hz; 200-600ms), theta (4.0-7.5Hz; 200-400ms), slow alpha (8.0-9.5Hz; 200-300ms), and fast alpha (10.0-12.5Hz; 100-200ms) ERO power were compared across group and task conditions. Compared to controls, alcoholics had higher impulsiveness scores on the Barrett Impulsiveness Scale (BIS-11) and made more errors on Go trials. Alcoholics showed significantly lower evoked delta, theta, and slow alpha power compared to controls for both Go and NoGo task conditions, and lower evoked fast alpha power compared to controls for only the NoGo condition. The results confirm previous findings and are suggestive of neurocognitive deficits while executing and suppressing a motor response. Based on findings in the alpha frequency ranges, it is further suggested that the inhibitory processing impairments in alcoholics may arise from inadequate early

  14. Inhibition of human ether-a-go-go-related gene potassium channels by alpha 1-adrenoceptor antagonists prazosin, doxazosin, and terazosin.

    Science.gov (United States)

    Thomas, Dierk; Wimmer, Anna-Britt; Wu, Kezhong; Hammerling, Bettina C; Ficker, Eckhard K; Kuryshev, Yuri A; Kiehn, Johann; Katus, Hugo A; Schoels, Wolfgang; Karle, Christoph A

    2004-05-01

    Human ether-a-go-go-related gene (HERG) potassium channels are expressed in multiple tissues including the heart and adenocarcinomas. In cardiomyocytes, HERG encodes the alpha-subunit underlying the rapid component of the delayed rectifier potassium current, I(Kr), and pharmacological reduction of HERG currents may cause acquired long QT syndrome. In addition, HERG currents have been shown to be involved in the regulation of cell proliferation and apoptosis. Selective alpha 1-adrenoceptor antagonists are commonly used in the treatment of hypertension and benign prostatic hyperplasia. Recently, doxazosin has been associated with an increased risk of heart failure. Moreover, quinazoline-derived alpha 1-inhibitors induce apoptosis in cardiomyocytes and prostate tumor cells independently of alpha1-adrenoceptor blockade. To assess the action of the effects of prazosin, doxazosin, and terazosin on HERG currents, we investigated their acute electrophysiological effects on cloned HERG potassium channels heterologously expressed in Xenopus oocytes and HEK 293 cells.Prazosin, doxazosin, and terazosin blocked HERG currents in Xenopus oocytes with IC(50) values of 10.1, 18.2, and 113.2 microM respectively, whereas the IC(50) values for HERG channel inhibition in human HEK 293 cells were 1.57 microM, 585.1 nM, and 17.7 microM. Detailed biophysical studies revealed that inhibition by the prototype alpha 1-blocker prazosin occurred in closed, open, and inactivated channels. Analysis of the voltage-dependence of block displayed a reduction of inhibition at positive membrane potentials. Frequency-dependence was not observed. Prazosin caused a negative shift in the voltage-dependence of both activation (-3.8 mV) and inactivation (-9.4 mV). The S6 mutations Y652A and F656A partially attenuated (Y652A) or abolished (F656A) HERG current blockade, indicating that prazosin binds to a common drug receptor within the pore-S6 region. In conclusion, this study demonstrates that HERG

  15. [Treatment of postpartal atony with prostaglandins].

    Science.gov (United States)

    Heinzl, S; Hendry, M

    1986-01-01

    Uterine contraction can be brought about at any time with prostaglandins. This effect is exploited in the treatment of postpartal atonia. Prostaglandin was administered intravenously to 21 women for postpartal atonia. In 19 women the bleeding subsequently stopped. There were no side effects of the treatment. These results are presented and discussed with reference to other data in the literature.

  16. Demyelinizing neurological disease after treatment with tumor necrosis factor alpha-inhibiting agents in a rheumatological outpatient clinic

    DEFF Research Database (Denmark)

    Theibich, Ali; Dreyer, Lene; Magyari, Melinda;

    2014-01-01

    Biological treatment with inhibitors of the pro-inflammatory cytokine TNF-alpha has dramatically improved the disease course of several chronic rheumatologic conditions. Adverse events (AEs) are primarily infections and hypersensitivity reactions. Demyelinizing neurological symptoms resembling...... multiple sclerosis (MS) have been described as a rare AE. During about 10-year use of anti TNF-alpha, the Danish Medicines Agency has recorded eight cases of MS like AEs. The objective of this study was to estimate the incidence of demyelinizing AEs both in the central and peripheral nervous system after...... treatment with anti TNF-alpha in a cohort of patients from a large rheumatologic outpatient clinic in Copenhagen. In a 4-year period from January 2008 to December 2011, approximately 550 patients annually were undergoing treatment with anti TNF-alpha inhibitors in our department. We collected data on all...

  17. Manassantin A and B isolated from Saururus chinensis inhibit TNF-alpha-induced cell adhesion molecule expression of human umbilical vein endothelial cells.

    Science.gov (United States)

    Kwon, Oh Eok; Lee, Hyun Sun; Lee, Seung Woong; Chung, Mi Yeon; Bae, Ki Hwan; Rho, Mun-Chual; Kim, Young-Kook

    2005-01-01

    Leukocyte adhesion to the vascular endothelium is a critical initiating step in inflammation and atherosclerosis. We have herein studied the effect of manassantin A (1) and B (2), dineolignans, on interaction of THP-1 monocytic cells and human umbilical vein endothelial cells (HUVEC) and expression of intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), and E-selectin in HUVEC. When HUVEC were pretreated with 1 and 2 followed by stimulation with TNF-alpha, adhesion of THP-1 cells to HUVEC decreased in dose-dependent manner with IC50 values of 5 ng/mL and 7 ng/mL, respectively, without cytotoxicity. Also, 1 and 2 inhibited TNF-alpha-induced up-regulation of ICAM-1, VCAM-1 and E-selectin. The present findings suggest that 1 and 2 prevent monocyte adhesion to HUVEC through the inhibition of ICAM-1, VCAM-1 and E-selectin expression stimulated by TNF-alpha, and may imply their usefulness for the prevention of atherosclerosis relevant to endothelial activation.

  18. Acute exercise reduces hepatic glucose production through inhibition of the Foxo1/HNF-4alpha pathway in insulin resistant mice.

    Science.gov (United States)

    De Souza, Cláudio T; Frederico, Marisa J S; da Luz, Gabrielle; Cintra, Dennys E; Ropelle, Eduardo R; Pauli, José R; Velloso, Lício A

    2010-06-15

    Protein hepatocyte nuclear factor 4alpha (HNF-4alpha) is atypically activated in the liver of diabetic rodents and contributes to hepatic glucose production. HNF-4alpha and Foxo1 can physically interact with each other and represent an important signal transduction pathway that regulates the synthesis of glucose in the liver. Foxo1 and HNF-4alpha interact with their own binding sites in the phosphoenolpyruvate carboxykinase (PEPCK) and glucose-6-phosphatase (G6Pase) promoters, and this binding is required for their effects on those promoters. However, the effect of physical activity on the HNF-4alpha/Foxo1 pathway is currently unknown. Here, we investigate the protein levels of HNF-4alpha and the HNF-4alpha/Foxo1 pathway in the liver of leptin-deficient (ob/ob) and diet-induced obese Swiss (DIO) mice after acute exercise. The ob/ob and DIO mice swam for four 30 min periods, with 5 min rest intervals for a total swimming time of 2h. Eight hours after the acute exercise protocol, the mice were submitted to an insulin tolerance test (ITT) and determination of biochemical and molecular parameters. Acute exercise improved insulin signalling, increasing insulin-stimulated Akt and Foxo1 phosphorylation and decreasing HNF-4alpha protein levels in the liver of DIO and ob/ob mice under fasting conditions. These phenomena were accompanied by a reduction in the expression of gluconeogenesis genes, such as PEPCK and G6Pase. Importantly, the PI3K inhibitor LY292004 reversed the acute effect of exercise on fasting hyperglycaemia, confirming the involvement of the PI3K pathway. The present study shows that exercise acutely improves the action of insulin in the liver of animal models of obesity and diabetes, resulting in increased phosphorylation and nuclear exclusion of Foxo1, and a reduction in the Foxo1/HNF-4alpha pathway. Since nuclear localization and the association of these proteins is involved in the activation of PEPCK and G6Pase, we believe that the regulation of Foxo1

  19. [Plasma hormone concentrations in induced abortion with local prostaglandin administration in the 1st trimester].

    Science.gov (United States)

    Rath, W; König, A; Ulbrich, R; Hilgers, R; Kuske, R; Kuhn, W

    1983-01-01

    Abortion was performed by curettage on 71 women with pregnancies between the 7th and the 13th week of gestation seven to eight hours after intracervical application of a tylose gel containing 3mg prostaglandin F2 alpha. Prior to the application of the prostaglandin and immediately before the surgical intervention a sonographic examination for determining the vitality of the pregnancy was carried out.--Plasma progesteron, estradiol and HPL levels were determined radioimmunologically prior to the application of prostaglandin, at four-hour intervals on the day of intervention, and 24, 48 and 72 hours after the intervention. In 22 women a complete or an incomplete abortion occurred; in two cases a blighted ovum was observed; 47 pregnancies, according to sonographic examination, remained intact until curettage. After seven to eight hours duration of the effect of the prostaglandin gel, progesterone levels were found to be reduced to 60.5 per cent and 17-beta-estradiol to 31.4 per cent of the initial values, whereas the HPL values fell below the specificity of the testing procedure (12.5 ng/ml). Comparative investigations of the pregnancies which, according to sonographic findings, remained intact until curettage and those which were aborted after the application of prostaglandin did not, in spite of low plasma progesterone and estradiol levels in the abortive group, reveal any statistically significant differences. The abortive effect--even with local application--of the prostaglandins was confirmed. Conclusions regarding the effective mechanism of the prostaglandins upon the fetoplacental unit and the function of the corpus luteum remain subject to speculation.

  20. Inhibition of prolyl oligopeptidase increases the survival of alpha-synuclein overexpressing cells after rotenone exposure by reducing alpha-synuclein oligomers.

    Science.gov (United States)

    Dokleja, Lana; Hannula, Mirva J; Myöhänen, Timo T

    2014-11-07

    α-Synuclein (aSyn) aggregation, mitochondrial dysfunction and oxidative damage has been shown to be related to the death of dopaminergic neurons in Parkinson's disease (PD). Prolyl oligopeptidase (PREP) is proposed to increase aSyn aggregation, and PREP inhibition has been shown to inhibit the aggregation process in vitro and in vivo. In this study, we investigated the effects of a specific PREP inhibitor, KYP-2047, on rotenone induced aSyn aggregation and increased the production of reactive oxygen species (ROS) in cells overexpressing A53T mutation of aSyn. Rotenone, a mitochondrial toxin that induces oxidative damage and aSyn aggregation, associated with PD pathology, was selected as a model for this study. The results showed that rotenone induced the formation of high-molecular-weight aSyn oligomers, and this was countered by simultaneous incubation with KYP-2047. Inhibition of PREP also decreased the production of ROS in [A53T]aSyn overexpressing cells, leading to improved cell viability.

  1. PPAR{alpha} agonist fenofibrate protects the kidney from hypertensive injury in spontaneously hypertensive rats via inhibition of oxidative stress and MAPK activity

    Energy Technology Data Exchange (ETDEWEB)

    Hou, Xiaoyang [Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education and Chinese Ministry of Health, Shandong University Qilu Hospital, 250012 Jinan, Shandong (China); Division of Cardiothoracic Surgery, The Michael E. DeBakey Department of Surgery, Baylor College of Medicine, BCM 390, One Baylor Plaza, Houston, TX 77030 (United States); Shen, Ying H. [Division of Cardiothoracic Surgery, The Michael E. DeBakey Department of Surgery, Baylor College of Medicine, BCM 390, One Baylor Plaza, Houston, TX 77030 (United States); Li, Chuanbao; Wang, Fei; Zhang, Cheng [Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education and Chinese Ministry of Health, Shandong University Qilu Hospital, 250012 Jinan, Shandong (China); Bu, Peili, E-mail: peilibu6320@hotmail.com [Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education and Chinese Ministry of Health, Shandong University Qilu Hospital, 250012 Jinan, Shandong (China); Zhang, Yun [Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education and Chinese Ministry of Health, Shandong University Qilu Hospital, 250012 Jinan, Shandong (China)

    2010-04-09

    Oxidative stress has been shown to play an important role in the development of hypertensive renal injury. Peroxisome proliferator-activated receptors {alpha} (PPAR{alpha}) has antioxidant effect. In this study, we demonstrated that fenofibrate significantly reduced proteinuria, inflammatory cell recruitment and extracellular matrix (ECM) proteins deposition in the kidney of SHRs without apparent effect on blood pressure. To investigate the mechanisms involved, we found that fenofibrate treatment markedly reduced oxidative stress accompanied by reduced activity of renal NAD(P)H oxidase, increased activity of Cu/Zn SOD, and decreased phosphorylation of p38MAPK and JNK in the kidney of SHRs. Taken together, fenofibrate treatment can protect against hypertensive renal injury without affecting blood pressure by inhibiting inflammation and fibrosis via suppression of oxidative stress and MAPK activity.

  2. Inhibition of Prostaglandin Reductase 2, a Putative Oncogene Overexpressed in Human Pancreatic Adenocarcinoma, Induces Oxidative Stress-Mediated Cell Death Involving xCT and CTH Gene Expressions through 15-Keto-PGE2.

    Directory of Open Access Journals (Sweden)

    Emily Yun-Chia Chang

    Full Text Available Prostaglandin reductase 2 (PTGR2 is the enzyme that catalyzes 15-keto-PGE2, an endogenous PPARγ ligand, into 13,14-dihydro-15-keto-PGE2. Previously, we have reported a novel oncogenic role of PTGR2 in gastric cancer, where PTGR2 was discovered to modulate ROS-mediated cell death and tumor transformation. In the present study, we demonstrated the oncogenic potency of PTGR2 in pancreatic cancer. First, we observed that the majority of the human pancreatic ductal adenocarcinoma tissues was stained positive for PTGR2 expression but not in the adjacent normal parts. In vitro analyses showed that silencing of PTGR2 expression enhanced ROS production, suppressed pancreatic cell proliferation, and promoted cell death through increasing 15-keto-PGE2. Mechanistically, silencing of PTGR2 or addition of 15-keto-PGE2 suppressed the expressions of solute carrier family 7 member 11 (xCT and cystathionine gamma-lyase (CTH, two important providers of intracellular cysteine for the generation of glutathione (GSH, which is widely accepted as the first-line antioxidative defense. The oxidative stress-mediated cell death after silencing of PTGR2 or addition of 15-keto-PGE2 was further abolished after restoring intracellular GSH concentrations and cysteine supply by N-acetyl-L-cysteine and 2-Mercaptomethanol. Our data highlight the therapeutic potential of targeting PTGR2/15-keto-PGE2 for pancreatic cancer.

  3. The mouse prostaglandin E receptor EP2 subtype: cloning, expression, and northern blot analysis.

    Science.gov (United States)

    Katsuyama, M; Nishigaki, N; Sugimoto, Y; Morimoto, K; Negishi, M; Narumiya, S; Ichikawa, A

    1995-09-25

    A functional cDNA clone for the mouse prostaglandin (PG) E receptor EP2 subtype was isolated from a mouse cDNA library. The mouse EP2 receptor consists of 362 amino acid residues with seven putative transmembrane domains. [3H]PGE2 bound specifically to the membrane of Chinese hamster ovary cells stably expressing the cloned receptor. This binding was displaced by unlabeled prostanoids in the order of PGE2 = PGE1 > iloprost, a stable PGI2 agonist > PGF2 alpha > PGD2. Binding was also inhibited by butaprost (an EP2 agonist) and to a lesser extent by M&B 28767 (an EP3 agonist), but not by sulprostone (an EP1 and EP3 agonist) or SC-19220 (an EP1 antagonist). PGE2 and butaprost increased the cAMP level in the Chinese hamster ovary cells in a concentration-dependent manner. Northern blot analysis revealed that EP2 mRNA is expressed most abundantly in the uterus, followed by the spleen, lung, thymus, ileum, liver, and stomach.

  4. Cloning and expression of a cDNA for mouse prostaglandin E receptor EP2 subtype.

    Science.gov (United States)

    Honda, A; Sugimoto, Y; Namba, T; Watabe, A; Irie, A; Negishi, M; Narumiya, S; Ichikawa, A

    1993-04-15

    A functional cDNA clone encoding mouse EP2 subtype of prostaglandin (PG) E receptor was isolated from a mouse cDNA library by cross-hybridization with the mouse EP3 subtype PGE receptor cDNA. The mouse EP2 receptor consists of 513 amino acid residues with putative seven-transmembrane domains. In contrast to EP3 receptor, this receptor possesses long third intracellular loop and carboxyl-terminal tail. [3H] PGE2 specifically bound to the membrane of mammalian COS cells transfected with the cDNA. The binding to the membrane was displaced with unlabeled PG in the order of PGE2 = PGE1 > iloprost > or = PGF2 alpha > or = PGD2. The binding was also inhibited by misoprostol, an EP2 and EP3 agonist, but not by sulprostone, an EP1 and EP3 agonist, and SC-19220, an EP1 antagonist. PGE2 markedly increased cAMP level in COS cells transfected with the cDNA. These results suggest that this receptor is EP2 subtype. Northern blot analysis demonstrated that the EP2 mRNA is widely expressed in various tissues, the abundant expression being observed in ileum, thymus, and mastocytoma P-815 cells.

  5. Inflammation-induced anorexia and fever are elicited by distinct prostaglandin dependent mechanisms, whereas conditioned taste aversion is prostaglandin independent.

    Science.gov (United States)

    Nilsson, Anna; Wilhelms, Daniel Björk; Mirrasekhian, Elahe; Jaarola, Maarit; Blomqvist, Anders; Engblom, David

    2017-03-01

    Systemic inflammation evokes an array of brain-mediated responses including fever, anorexia and taste aversion. Both fever and anorexia are prostaglandin dependent but it has been unclear if the cell-type that synthesizes the critical prostaglandins is the same. Here we show that pharmacological inhibition or genetic deletion of cyclooxygenase (COX)-2, but not of COX-1, attenuates inflammation-induced anorexia. Mice with deletions of COX-2 selectively in brain endothelial cells displayed attenuated fever, as demonstrated previously, but intact anorexia in response to peripherally injected lipopolysaccharide (10μg/kg). Whereas intracerebroventricular injection of a cyclooxygenase inhibitor markedly reduced anorexia, deletion of COX-2 selectively in neural cells, in myeloid cells or in both brain endothelial and neural cells had no effect on LPS-induced anorexia. In addition, COX-2 in myeloid and neural cells was dispensable for the fever response. Inflammation-induced conditioned taste aversion did not involve prostaglandin signaling at all. These findings collectively show that anorexia, fever and taste aversion are triggered by distinct routes of immune-to-brain signaling.

  6. The interferon-gamma-induced GTPase, mGBP-2, inhibits tumor necrosis factor alpha (TNF-alpha) induction of matrix metalloproteinase-9 (MMP-9) by inhibiting NF-kappaB and Rac protein.

    Science.gov (United States)

    Balasubramanian, Sujata; Fan, Meiyun; Messmer-Blust, Angela F; Yang, Chuan H; Trendel, Jill A; Jeyaratnam, Jonathan A; Pfeffer, Lawrence M; Vestal, Deborah J

    2011-06-03

    Matrix metalloproteinase-9 (MMP-9) is important in numerous normal and pathological processes, including the angiogenic switch during tumor development and tumor metastasis. Whereas TNF-α and other cytokines up-regulate MMP-9 expression, interferons (IFNs) inhibit MMP-9 expression. We found that IFN-γ treatment or forced expression of the IFN-induced GTPase, mGBP-2, inhibit TNF-α-induced MMP-9 expression in NIH 3T3 fibroblasts, by inhibiting MMP-9 transcription. The NF-κB transcription factor is required for full induction of MMP-9 by TNF-α. Both IFN-γ and mGBP-2 inhibit the transcription of a NF-κB-dependent reporter construct, suggesting that mGBP-2 inhibits MMP-9 induction via inhibition of NF-κB-mediated transcription. Interestingly, mGBP-2 does not inhibit TNF-α-induced degradation of IκBα or p65/RelA translocation into the nucleus. However, mGBP-2 inhibits p65 binding to a κB oligonucleotide probe in gel shift assays and to the MMP-9 promoter in chromatin immunoprecipitation assays. In addition, TNF-α activation of NF-κB in NIH 3T3 cells is dependent on Rac activation, as evidenced by the inhibition of TNF-α induction of NF-κB-mediated transcription by a dominant inhibitory form of Rac1. A role for Rac in the inhibitory action of mGBP-2 on NF-κB is further shown by the findings that mGBP-2 inhibits TNF-α activation of endogenous Rac and constitutively activate Rac can restore NF-κB transcription in the presence of mGBP-2. This is a novel mechanism by which IFNs can inhibit the cytokine induction of MMP-9 expression.

  7. Pharmacogenomics of Prostaglandin and Leukotriene Receptors

    Science.gov (United States)

    Cornejo-García, José A.; Perkins, James R.; Jurado-Escobar, Raquel; García-Martín, Elena; Agúndez, José A.; Viguera, Enrique; Pérez-Sánchez, Natalia; Blanca-López, Natalia

    2016-01-01

    Individual genetic background together with environmental effects are thought to be behind many human complex diseases. A number of genetic variants, mainly single nucleotide polymorphisms (SNPs), have been shown to be associated with various pathological and inflammatory conditions, representing potential therapeutic targets. Prostaglandins (PTGs) and leukotrienes (LTs) are eicosanoids derived from arachidonic acid and related polyunsaturated fatty acids that participate in both normal homeostasis and inflammatory conditions. These bioactive lipid mediators are synthesized through two major multistep enzymatic pathways: PTGs by cyclooxygenase and LTs by 5-lipoxygenase. The main physiological effects of PTGs include vasodilation and vascular leakage (PTGE2); mast cell maturation, eosinophil recruitment, and allergic responses (PTGD2); vascular and respiratory smooth muscle contraction (PTGF2), and inhibition of platelet aggregation (PTGI2). LTB4 is mainly involved in neutrophil recruitment, vascular leakage, and epithelial barrier function, whereas cysteinyl LTs (CysLTs) (LTC4, LTD4, and LTE4) induce bronchoconstriction and neutrophil extravasation, and also participate in vascular leakage. PTGs and LTs exert their biological functions by binding to cognate receptors, which belong to the seven transmembrane, G protein-coupled receptor superfamily. SNPs in genes encoding these receptors may influence their functionality and have a role in disease susceptibility and drug treatment response. In this review we summarize SNPs in PTGs and LTs receptors and their relevance in human diseases. We also provide information on gene expression. Finally, we speculate on future directions for this topic. PMID:27708579

  8. PHARMACOGENOMICS OF PROSTAGLANDIN AND LEUKOTRIENE RECEPTORS

    Directory of Open Access Journals (Sweden)

    José Antonio Cornejo-García

    2016-09-01

    Full Text Available Individual genetic background together with environmental effects are thought to be behind many human complex diseases. A number of genetic variants, mainly single nucleotide polymorphisms (SNPs, have been shown to be associated with various pathological and inflammatory conditions, representing potential therapeutic targets. Prostaglandins (PTGs and leukotrienes (LTs are eicosanoids derived from arachidonic acid and related polyunsaturated fatty acids that participate in both normal homeostasis and inflammatory conditions. These bioactive lipid mediators are synthesised through two major multistep enzymatic pathways: PTGs by cyclooxygenase and LTs by 5-lipoxygenase. The main physiological effects of PTGs include vasodilation and vascular leakage (PTGE2; mast cell maturation, eosinophil recruitment and allergic responses (PTGD2; vascular and respiratory smooth muscle contraction (PTGF2, and inhibition of platelet aggregation (PTGI2. LTB4 is mainly involved in neutrophil recruitment, vascular leakage, and epithelial barrier function, whereas cysteinyl LTs (CysLTs (LTC4, LTD4 and LTE4 induce bronchoconstriction and neutrophil extravasation, and also participate in vascular leakage. PTGs and LTs exert their biological functions by binding to cognate receptors, which belong to the seven transmembrane, G protein-coupled receptor superfamily. SNPs in genes encoding these receptors may influence their functionality and have a role in disease susceptibility and drug treatment response. In this review we summarize SNPs in PTGs and LTs receptors and their relevance in human diseases. We also provide information on gene expression. Finally, we speculate on future directions for this topic.

  9. Amitriptyline may have a supportive role in cancer treatment by inhibiting glutathione S-transferase pi (GST-π) and alpha (GST-α).

    Science.gov (United States)

    Kulaksiz-Erkmen, Gulnihal; Dalmizrak, Ozlem; Dincsoy-Tuna, Gamze; Dogan, Arın; Ogus, I Hamdi; Ozer, Nazmi

    2013-02-01

    A tricyclic anti-depressant, amitriptyline, is a highly prescribed drug for cancer patients for mood elevation but there are limited studies about the interaction of amitriptyline with glutathione S-transferases pi (GST-π) and glutathione S-transferases alpha (GST-α). GST isozymes have been implicated in chemotherapeutic drug resistance. We demonstrated that the concentration dependent inhibition of GST-π and GST-α by amitriptyline followed inverse hyperbolic inhibition curves with IC(50) values of 5.54 and 8.32 mM, respectively. When the varied substrate was GSH, amitriptyline inhibited both isozymes competitively and similar K(i) values were found for GST-π (K(i) = 1.61 ± 0.17 mM) and GST-α (K(i) = 1.45 ± 0.20 mM). On the other hand, when the varied substrate was CDNB, the inhibition types were non-competitive for GST-π (K(i) = 1.98 ± 0.31 mM) and competitive for GST-α (K(i) = 1.57 ± 0.16 mM). Amitriptyline, in addition to its antidepressant effect, might also have a minor supportive role on the effectiveness of the anticancer drugs by decreasing their elimination through inhibiting GST-π and GST-α.

  10. Maternal serum alpha-fetoprotein levels are normal in Fanconi anemia: Can it be a lack of postnatal inhibition of AFP gene resulting in the elevation?

    Science.gov (United States)

    Aslan, Deniz; Karabacak, Recep Onur; Aslan, Oner Deniz

    2017-04-01

    We investigated the feasibility of using serum alpha-fetoprotein (AFP) levels as a screening test for prenatal diagnosis of Fanconi anemia (FA). Serial measurements in maternal serum were recorded. Parents, both heterozygous for FA, had declined prenatal molecular testing. The infant was born with no somatic abnormalities, and FA was confirmed by postnatal molecular analysis. Maternal serum AFP levels during each trimester of pregnancy were normal indicating that these levels cannot be used as a screening test in prenatal diagnosis. Three-year follow-up after birth showed constantly elevated serum levels in the patient from the start, suggesting a lack of postnatal inhibition on AFP gene.

  11. R-alpha-methylhistamine-induced inhibition of gastric acid secretion in pylorus-ligated rats via central histamine H3 receptors.

    OpenAIRE

    Barocelli, E; Ballabeni, V.; Chiavarini, M.; Impicciatore, M

    1995-01-01

    1. The effect of central H3 histamine receptor activation on gastric acid and pepsin production has been investigated in pylorus-ligated rats. 2. Intracerebroventricular injections (i.c.v.) of the selective H3 agonist, R-alpha-methylhistamine (0.5-50 nmol per rat) caused a dose-dependent inhibition of gastric acid secretion while intravenous administration (5-500 nmol per rat) was completely ineffective. 3. I.c.v. microinjections of mepyramine, tiotidine and thioperamide (51 nmol per rat), se...

  12. Indomethacin and paracetamol : Interaction with prostaglandin synthesis in the rat stomach

    NARCIS (Netherlands)

    Kolfschoten, A.A. van; Hagelen, F.; Noordwijk, J. van

    1982-01-01

    Using ex vivo incubation of mucosal strips the production of prostaglandins (I2- and E-like PGs) in the rat stomach was demonstrated by bioassay. Indomethacin inhibited this PG synthesis 1 and 4 h after oral drug administration. Paracetamol stimulated the production of PGs when given by itself but c

  13. Interactions of prostaglandin A2 with the glutathione-mediated biotransformation system

    NARCIS (Netherlands)

    Iersel, M.L.P.S. van; Cnubben, N.H.P.; Smink, N.; Koeman, J.H.; Bladeren, P.J. van

    1999-01-01

    The cyclopentenone prostaglandin A2 (PGA2) is known to inhibit cell proliferation, and metabolism of this compound thus might be important in controlling its ultimate function. The glutathione-related metabolism of PGA2 was therefore investigated both with purified glutathione S-transferase P1-1 (GS

  14. Role of pathogen-derived cell wall carbohydrates and prostaglandin E2 in immune response and suppression of fish immunity by the oomycete Saprolegnia parasitica.

    Science.gov (United States)

    Belmonte, Rodrigo; Wang, Tiehui; Duncan, Gary J; Skaar, Ida; Mélida, Hugo; Bulone, Vincent; van West, Pieter; Secombes, Christopher J

    2014-11-01

    Saprolegnia parasitica is a freshwater oomycete that is capable of infecting several species of fin fish. Saprolegniosis, the disease caused by this microbe, has a substantial impact on Atlantic salmon aquaculture. No sustainable treatment against saprolegniosis is available, and little is known regarding the host response. In this study, we examined the immune response of Atlantic salmon to S. parasitica infection and to its cell wall carbohydrates. Saprolegnia triggers a strong inflammatory response in its host (i.e., induction of interleukin-1β1 [IL-1β1], IL-6, and tumor necrosis factor alpha), while severely suppressing the expression of genes associated with adaptive immunity in fish, through downregulation of T-helper cell cytokines, antigen presentation machinery, and immunoglobulins. Oomycete cell wall carbohydrates were recognized by fish leukocytes, triggering upregulation of genes involved in the inflammatory response, similar to what is observed during infection. Our data suggest that S. parasitica is capable of producing prostaglandin [corrected] E2 (PGE2) in vitro, a metabolite not previously shown to be produced by oomycetes, and two proteins with homology to vertebrate enzymes known to play a role in prostaglandin biosynthesis have been identified in the oomycete genome. Exogenous PGE2 was shown to increase the inflammatory response in fish leukocytes incubated with cell wall carbohydrates while suppressing genes involved in cellular immunity (gamma interferon [IFN-γ] and the IFN-γ-inducible protein [γ-IP]). Inhibition of S. parasitica zoospore germination and mycelial growth by two cyclooxygenase inhibitors (aspirin and indomethacin) also suggests that prostaglandins may be involved in oomycete development.

  15. Structural and mutational analyses of the interaction between the barley alpha-amylase/subtilisin inhibitor and the subtilisin savinase reveal a novel mode of inhibition.

    Science.gov (United States)

    Micheelsen, Pernille Ollendorff; Vévodová, Jitka; De Maria, Leonardo; Ostergaard, Peter Rahbek; Friis, Esben Peter; Wilson, Keith; Skjøt, Michael

    2008-07-18

    Subtilisins represent a large class of microbial serine proteases. To date, there are three-dimensional structures of proteinaceous inhibitors from three families in complex with subtilisins in the Protein Data Bank. All interact with subtilisin via an exposed loop covering six interacting residues. Here we present the crystal structure of the complex between the Bacillus lentus subtilisin Savinase and the barley alpha-amylase/subtilisin inhibitor (BASI). This is the first reported structure of a cereal Kunitz-P family inhibitor in complex with a subtilisin. Structural analysis revealed that BASI inhibits Savinase in a novel way, as the interacting loop is shorter than loops previously reported. Mutational analysis showed that Thr88 is crucial for the inhibition, as it stabilises the interacting loop through intramolecular interactions with the BASI backbone.

  16. The novel hypoxic cytotoxin, TX-2098 has antitumor effect in pancreatic cancer; possible mechanism through inhibiting VEGF and hypoxia inducible factor-1{alpha} targeted gene expression

    Energy Technology Data Exchange (ETDEWEB)

    Miyake, Kotaro, E-mail: hif.panc@gmail.com [Department of Surgery, Institute of Health Biosciences, The University of Tokushima Graduate School, Tokushima 770-8503 (Japan); Nishioka, Masanori; Imura, Satoru; Batmunkh, Erdenebulgan [Department of Surgery, Institute of Health Biosciences, The University of Tokushima Graduate School, Tokushima 770-8503 (Japan); Uto, Yoshihiro [Department of Biological Science and Technology, Institute of Socio Technosciences, The University of Tokushima Graduate School, Tokushima 770-8503 (Japan); Nagasawa, Hideko [Laboratory of Pharmaceutical and Medicinal Chemistry, Gifu Pharmaceutical University, Gifu 501-1196 (Japan); Hori, Hitoshi [Department of Biological Science and Technology, Institute of Socio Technosciences, The University of Tokushima Graduate School, Tokushima 770-8503 (Japan); Shimada, Mitsuo [Department of Surgery, Institute of Health Biosciences, The University of Tokushima Graduate School, Tokushima 770-8503 (Japan)

    2012-08-01

    Tumor hypoxia has been considered to be a potential therapeutic target, because hypoxia is a common feature of solid tumors and is associated with their malignant phenotype. In the present study, we investigated the antitumor effect of a novel hypoxic cytotoxin, 3-[2-hydroxyethyl(methyl)amino]-2-quinoxalinecarbonitrile 1,4-dioxide (TX-2098) in inhibiting the expression of hypoxia inducible factor-1{alpha} (HIF-1{alpha}), and consequently vascular endothelial cell growth factor (VEGF) expression in pancreatic cancer. The antitumor effects of TX-2098 under hypoxia were tested against various human pancreatic cancer cell lines using WST-8 assay. VEGF protein induced pancreatic cancer was determined on cell-free supernatant by ELISA. Moreover, nude mice bearing subcutaneously (s.c.) or orthotopically implanted human SUIT-2 were treated with TX-2098. Tumor volume, survival and expression of HIF-1 and associated molecules were evaluated in treatment versus control groups. In vitro, TX-2098 inhibited the proliferation of various pancreatic cancer cell lines. In s.c model, tumors from nude mice injected with pancreatic cancer cells and treated with TX-2098 showed significant reductions in volume (P < 0.01 versus control). Quantitative real-time reverse transcription-PCR analysis revealed that TX-2098 significantly inhibited mRNA expression of the HIF-1 associated molecules, VEGF, glucose transporter 1 and Aldolase A (P < 0.01 versus control). These treatments also prolong the survival in orthotopic models. These results suggest that the effect of TX-2098 in pancreatic cancer might be correlated with the expression of VEGF and HIF-1 targeted molecules. -- Highlights: Black-Right-Pointing-Pointer We designed and synthesized novel hypoxic cytoxin, TX-2098. Black-Right-Pointing-Pointer TX-2098 inhibited the proliferation of human pancreatic cancer cells than TPZ. Black-Right-Pointing-Pointer TX-2098 reduced VEGF protein level than TPZ. Black-Right-Pointing-Pointer TX-2098

  17. In vitro alpha glucosidase inhibition and free-radical scavenging activity of propolis from Thai stingless bees in mangosteen orchard

    Directory of Open Access Journals (Sweden)

    Boonyadist Vongsak

    2015-10-01

    Full Text Available ABSTRACTThe chemical component and biological activity of propolis depend on flora area of bee collection and bee species. In the study, the propolis from three stingless bee species, Lepidotrigona ventralis Smith, Lepidotrigona terminata Smith, and Tetragonula pagdeni Schwarz, was collected in the same region of mangosteen garden from Thailand. Total phenolic content, alpha glucosidase inhibitory effect, and free-radical scavenging activity using FRAP, ABTS, DPPH assays were determined. The most potent activity of propolis extract was investigated for bioactive compounds and their quantity. The ethanol extract of T. pagdeni propolis had the highest total phenolic content 12.83 ± 0.72 g of gallic acid equivalents in 100 g of the extract, and the strongest alpha glucosidase inhibitory effect with the IC50 of 70.79 ± 6.44 µg/ml. The free-radical scavenging activity evaluated by FRAP, ABTS, DPPH assays showed the FRAP value of 279.70 ± 20.55 µmol FeSO4 equivalent/g extract and the IC50 of 59.52 ± 10.76 and 122.71 ± 11.76 µg/ml, respectively. Gamma- and alpha-mangostin from T. pagdeni propolis extract were isolated and determined for the biological activity. Gamma-mangostin exhibited the strongest activity for both alpha glucosidase inhibitory effect and free-radical scavenging activity. Using HPLC quantitative analysis method, the content of gamma- and alpha-mangostin in the extract was found to be 0.94 ± 0.01 and 2.77 ± 0.08% (w/w, respectively. These findings suggested that T. pagdeni propolis may be used as a more suitable raw material for nutraceutical and pharmaceutical products and these mangostin derivatives as markers.

  18. Photochemically enhanced binding of small molecules to the tumor necrosis factor receptor-1 inhibits the binding of TNF-[alpha

    Energy Technology Data Exchange (ETDEWEB)

    Carter, Percy H.; Scherle, Peggy A.; Muckelbauer, Jodi K.; Voss, Matthew E.; Liu, Rui-qin; Thompson III, Lorin A.; Xu, Meizhong; Lo, Yvonne C.; Li, Zhong; Strzemienski, Paul; Yang, Gengjie; Falahatpishen, Nikoo; Farrow, Neil A.; Tebben, Andrew J.; Underwood, Denis; Trzaskos, James M.; Friedman, Steven M.; Newton, Robert C.; Decicco, Carl P. (DuPont)

    2010-03-05

    The binding of tumor necrosis factor alpha (TNF-{alpha}) to the type-1 TNF receptor (TNFRc1) plays an important role in inflammation. Despite the clinical success of biologics (antibodies, soluble receptors) for treating TNF-based autoimmune conditions, no potent small molecule antagonists have been developed. Our screening of chemical libraries revealed that N-alkyl 5-arylidene-2-thioxo-1,3-thiazolidin-4-ones were antagonists of this protein-protein interaction. After chemical optimization, we discovered IW927, which potently disrupted the binding of TNF-{alpha} to TNFRc1 (IC{sub 50} = 50 nM) and also blocked TNF-stimulated phosphorylation of I{kappa}-B in Ramos cells (IC{sub 50} = 600 nM). This compound did not bind detectably to the related cytokine receptors TNFRc2 or CD40, and did not display any cytotoxicity at concentrations as high as 100 {micro}M. Detailed evaluation of this and related molecules revealed that compounds in this class are 'photochemically enhanced' inhibitors, in that they bind reversibly to the TNFRc1 with weak affinity (ca. 40-100 mM) and then covalently modify the receptor via a photochemical reaction. We obtained a crystal structure of IV703 (a close analog of IW927) bound to the TNFRc1. This structure clearly revealed that one of the aromatic rings of the inhibitor was covalently linked to the receptor through the main-chain nitrogen of Ala-62, a residue that has already been implicated in the binding of TNF-{alpha} to the TNFRc1. When combined with the fact that our inhibitors are reversible binders in light-excluded conditions, the results of the crystallography provide the basis for the rational design of nonphotoreactive inhibitors of the TNF-{alpha}-TNFRc1 interaction.

  19. Photochemically enhanced binding of small molecules to the tumor necrosis factor receptor-1 inhibits the binding of TNF-alpha.

    Science.gov (United States)

    Carter, P H; Scherle, P A; Muckelbauer, J K; Voss, M E; Liu, R Q; Thompson, L A; Tebben, A J; Solomon, K A; Lo, Y C; Li, Z; Strzemienski, P; Yang, G; Falahatpisheh, N; Xu, M; Wu, Z; Farrow, N A; Ramnarayan, K; Wang, J; Rideout, D; Yalamoori, V; Domaille, P; Underwood, D J; Trzaskos, J M; Friedman, S M; Newton, R C; Decicco, C P; Muckelbauer, J A

    2001-10-09

    The binding of tumor necrosis factor alpha (TNF-alpha) to the type-1 TNF receptor (TNFRc1) plays an important role in inflammation. Despite the clinical success of biologics (antibodies, soluble receptors) for treating TNF-based autoimmune conditions, no potent small molecule antagonists have been developed. Our screening of chemical libraries revealed that N-alkyl 5-arylidene-2-thioxo-1,3-thiazolidin-4-ones were antagonists of this protein-protein interaction. After chemical optimization, we discovered IW927, which potently disrupted the binding of TNF-alpha to TNFRc1 (IC(50) = 50 nM) and also blocked TNF-stimulated phosphorylation of Ikappa-B in Ramos cells (IC(50) = 600 nM). This compound did not bind detectably to the related cytokine receptors TNFRc2 or CD40, and did not display any cytotoxicity at concentrations as high as 100 microM. Detailed evaluation of this and related molecules revealed that compounds in this class are "photochemically enhanced" inhibitors, in that they bind reversibly to the TNFRc1 with weak affinity (ca. 40-100 microM) and then covalently modify the receptor via a photochemical reaction. We obtained a crystal structure of IV703 (a close analog of IW927) bound to the TNFRc1. This structure clearly revealed that one of the aromatic rings of the inhibitor was covalently linked to the receptor through the main-chain nitrogen of Ala-62, a residue that has already been implicated in the binding of TNF-alpha to the TNFRc1. When combined with the fact that our inhibitors are reversible binders in light-excluded conditions, the results of the crystallography provide the basis for the rational design of nonphotoreactive inhibitors of the TNF-alpha-TNFRc1 interaction.

  20. 6-Gingerol inhibits ROS and iNOS through the suppression of PKC-{alpha} and NF-{kappa}B pathways in lipopolysaccharide-stimulated mouse macrophages

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Tzung-Yan, E-mail: joyamen@mail.cgu.edu.tw [Graduate Institute of Traditional Chinese Medicine, Chang Gung University, No. 259, Wen-Hwa 1st Road, Kwei-Shan Tao-Yuan 333, Taiwan (China); Lee, Ko-Chen [School of Traditional Chinese Medicine, Chang Gung University, Taiwan (China); Center for Traditional Chinese Medicine, Chang Gung Memorial Hospital, Taoyuan, Taiwan (China); Chen, Shih-Yuan [Graduate Institute of Traditional Chinese Medicine, Chang Gung University, No. 259, Wen-Hwa 1st Road, Kwei-Shan Tao-Yuan 333, Taiwan (China); Chang, Hen-Hong [Graduate Institute of Traditional Chinese Medicine, Chang Gung University, No. 259, Wen-Hwa 1st Road, Kwei-Shan Tao-Yuan 333, Taiwan (China); Center for Traditional Chinese Medicine, Chang Gung Memorial Hospital, Taoyuan, Taiwan (China)

    2009-04-24

    Inflammation is involved in numerous diseases, including chronic inflammatory diseases and the development of cancer. Many plants possess a variety of biological activities, including antifungal, antibacterial and anti-inflammatory activities. However, our understanding of the anti-inflammatory effects of 6-gingerol is very limited. We used lipopolysaccharide (LPS)-stimulated macrophages as a model of inflammation to investigate the anti-inflammatory effects of 6-gingerol, which contains phenolic structure. We found that 6-gingerol exhibited an anti-inflammatory effect. 6-Gingerol could decrease inducible nitric oxide synthase and TNF-{alpha} expression through suppression of I-{kappa}B{alpha} phosphorylation, NF-{kappa}B nuclear activation and PKC-{alpha} translocation, which in turn inhibits Ca{sup 2+} mobilization and disruption of mitochondrial membrane potential in LPS-stimulated macrophages. Here, we demonstrate that 6-gingerol acts as an anti-inflammatory agent by blocking NF-{kappa}B and PKC signaling, and may be developed as a useful agent for the chemoprevention of cancer or inflammatory diseases.

  1. A pseudopterane diterpene isolated from the octocoral Pseudopterogorgia acerosa inhibits the inflammatory response mediated by TLR-ligands and TNF-alpha in macrophages.

    Science.gov (United States)

    González, Yisett; Doens, Deborah; Santamaría, Ricardo; Ramos, Marla; Restrepo, Carlos M; Barros de Arruda, Luciana; Lleonart, Ricardo; Gutiérrez, Marcelino; Fernández, Patricia L

    2013-01-01

    Several diterpenoids isolated from terrestrial and marine environments have been identified as important anti-inflammatory agents. Although considerable progress has been made in the area of anti-inflammatory treatment, the search for more effective and safer compounds is a very active field of research. In this study we investigated the anti-inflammatory effects of a known pseudopterane diterpene (referred here as compound 1) isolated from the octocoral Pseudopterogorgia acerosa on the tumor necrosis factor- alpha (TNF-α) and TLRs- induced response in macrophages. Compound 1 inhibited the expression and secretion of the inflammatory mediators TNF-α, interleukin (IL)-6, IL-1β, nitric oxide (NO), interferon gamma-induced protein 10 (IP-10), ciclooxygenase (COX)-2, inducible nitric oxide synthase (iNOS) and monocyte chemoattractant protein-1 (MCP-1) induced by LPS in primary murine macrophages. This effect was associated with the inhibition of IκBα degradation and subsequent activation of NFκB. Compound 1 also inhibited the expression of the co-stimulatory molecules CD80 and CD86, which is a hallmark of macrophage activation and consequent initiation of an adaptive immune response. The anti-inflammatory effect was not exclusive to LPS because compound 1 also inhibited the response of macrophages to TNF-α and TLR2 and TLR3 ligands. Taken together, these results indicate that compound 1 is an anti-inflammatory molecule, which modulates a variety of processes occurring in macrophage activation.

  2. A pseudopterane diterpene isolated from the octocoral Pseudopterogorgia acerosa inhibits the inflammatory response mediated by TLR-ligands and TNF-alpha in macrophages.

    Directory of Open Access Journals (Sweden)

    Yisett González

    Full Text Available Several diterpenoids isolated from terrestrial and marine environments have been identified as important anti-inflammatory agents. Although considerable progress has been made in the area of anti-inflammatory treatment, the search for more effective and safer compounds is a very active field of research. In this study we investigated the anti-inflammatory effects of a known pseudopterane diterpene (referred here as compound 1 isolated from the octocoral Pseudopterogorgia acerosa on the tumor necrosis factor- alpha (TNF-α and TLRs- induced response in macrophages. Compound 1 inhibited the expression and secretion of the inflammatory mediators TNF-α, interleukin (IL-6, IL-1β, nitric oxide (NO, interferon gamma-induced protein 10 (IP-10, ciclooxygenase (COX-2, inducible nitric oxide synthase (iNOS and monocyte chemoattractant protein-1 (MCP-1 induced by LPS in primary murine macrophages. This effect was associated with the inhibition of IκBα degradation and subsequent activation of NFκB. Compound 1 also inhibited the expression of the co-stimulatory molecules CD80 and CD86, which is a hallmark of macrophage activation and consequent initiation of an adaptive immune response. The anti-inflammatory effect was not exclusive to LPS because compound 1 also inhibited the response of macrophages to TNF-α and TLR2 and TLR3 ligands. Taken together, these results indicate that compound 1 is an anti-inflammatory molecule, which modulates a variety of processes occurring in macrophage activation.

  3. A Pseudopterane Diterpene Isolated From the Octocoral Pseudopterogorgia acerosa Inhibits the Inflammatory Response Mediated by TLR-Ligands and TNF-Alpha in Macrophages

    Science.gov (United States)

    González, Yisett; Doens, Deborah; Santamaría, Ricardo; Ramos, Marla; Restrepo, Carlos M.; Barros de Arruda, Luciana; Lleonart, Ricardo; Gutiérrez, Marcelino; Fernández, Patricia L.

    2013-01-01

    Several diterpenoids isolated from terrestrial and marine environments have been identified as important anti-inflammatory agents. Although considerable progress has been made in the area of anti-inflammatory treatment, the search for more effective and safer compounds is a very active field of research. In this study we investigated the anti-inflammatory effects of a known pseudopterane diterpene (referred here as compound 1) isolated from the octocoral Pseudopterogorgia acerosa on the tumor necrosis factor- alpha (TNF-α) and TLRs- induced response in macrophages. Compound 1 inhibited the expression and secretion of the inflammatory mediators TNF-α, interleukin (IL)-6, IL-1β, nitric oxide (NO), interferon gamma-induced protein 10 (IP-10), ciclooxygenase (COX)-2, inducible nitric oxide synthase (iNOS) and monocyte chemoattractant protein-1 (MCP-1) induced by LPS in primary murine macrophages. This effect was associated with the inhibition of IκBα degradation and subsequent activation of NFκB. Compound 1 also inhibited the expression of the co-stimulatory molecules CD80 and CD86, which is a hallmark of macrophage activation and consequent initiation of an adaptive immune response. The anti-inflammatory effect was not exclusive to LPS because compound 1 also inhibited the response of macrophages to TNF-α and TLR2 and TLR3 ligands. Taken together, these results indicate that compound 1 is an anti-inflammatory molecule, which modulates a variety of processes occurring in macrophage activation. PMID:24358331

  4. Interaction of berberine with human platelet. alpha. sub 2 adrenoceptors

    Energy Technology Data Exchange (ETDEWEB)

    Hui, Ka Kit; Yu, Jun Liang; Chan, Wai Fong A.; Tse, E. (UCLA School of Medicine, (USA))

    1991-01-01

    Berberine was found to inhibit competitively the specific binding of ({sup 3}H)-yohimbine. The displacement curve was parallel to those of clonidine, epinephrine, norepinephrine, with the rank order of potency (IC{sub 50}) being clonidine {gt} epinephrine {gt} norepinephrine (14.5 {mu}M) = berberine. Increasing concentrations of berberine from 0.1 {mu}M to 10 {mu}M inhibited ({sup 3}H)-yohimbine binding, shifting the saturation binding curve to the right without decreasing the maximum binding capacity. In platelet cyclic AMP accumulation experiments, berberine at concentrations of 0.1 {mu}M to 0.1 mM inhibited the cAMP accumulation induced by 10 {mu}M prostaglandin E{sub 1} in a dose dependent manner, acting as an {alpha}{sub 2} adrenoceptor agonist. In the presence of L-epinephrine, berberine blocked the inhibitory effect of L-epinephrine behaving as an {alpha}{sub 2} adrenoceptor antagonist.

  5. Suppressor of cytokine signalling-3 inhibits Tumor necrosis factor-alpha induced apoptosis and signalling in beta cells

    DEFF Research Database (Denmark)

    Bruun, Christine; Heding, Peter E; Rønn, Sif G

    2009-01-01

    Tumor necrosis factor-alpha (TNFalpha) is a pro-inflammatory cytokine involved in the pathogenesis of several diseases including type 1 diabetes mellitus (T1DM). TNFalpha in combination with interleukin-1-beta (IL-1beta) and/or interferon-gamma (IFNgamma) induces specific destruction of the pancr......Tumor necrosis factor-alpha (TNFalpha) is a pro-inflammatory cytokine involved in the pathogenesis of several diseases including type 1 diabetes mellitus (T1DM). TNFalpha in combination with interleukin-1-beta (IL-1beta) and/or interferon-gamma (IFNgamma) induces specific destruction...... in INSr3#2 cells and in primary rat islets. Furthermore, SOCS-3 repressed TNFalpha-induced degradation of IkappaB, NFkappaB DNA binding and transcription of the NFkappaB-dependent MnSOD promoter. Finally, expression of Socs-3 mRNA was induced by TNFalpha in rat islets in a transient manner with maximum...

  6. The whipworm (Trichuris suis) secretes prostaglandin E2 to suppress proinflammatory properties in human dendritic cells

    DEFF Research Database (Denmark)

    Laan, Lisa C; Williams, Andrew R; Stavenhagen, Kathrin;

    2017-01-01

    /mg protein) within their excretory/secretory products but few related lipid mediators as established by metabololipidomic analysis. Culture of T. suis with several cyclooxygenase (COX) inhibitors that inhibit mammalian prostaglandin synthesis affected the worm's motility but did not inhibit PGE2 secretion...

  7. In vitro antibacterial, alpha-amylase inhibition potential of three nudibranchs extracts from South East coast of India

    Institute of Scientific and Technical Information of China (English)

    Giji Sadhasivam; Arumugam Muthuvel; Wanjale Mrunal Vitthal; Abirami Pachaiyappan; Mohan Kumar; Balasubramanian Thangavel

    2013-01-01

    Objective: To study the antibacterial and antiamylase properties of methanol and acetone extracts of nudibranchs including Bursatella leachii (B. leachii), Kalinga ornata (K. ornata),Aplysia sp. Methods: Crude methanol and acetone extracts of sea slugs were tested for inhibition of fish bacterial pathogens' growth through disc diffusion method. The activity was measured based on the formation of inhibition zone around the disc impregnated with crude extracts. The α-amylase inhibitory effect was also measured calorimetrically. The chemical fingerprinting of the extract was recorded with HPTLC and GC-MS. Results: The solvent extracts of all the three sea slugs showed antibacterial property. The maximum zone of inhibition (>15-20 mm) was recorded for methanol and acetone extracts of K.ornata. The methanol extract of Aplysia sp. exhibited 93% inhibition against α-amylase, following by B. leachii (methanol) 70.6% and K. ornata (methanol) 49.03% inhibition respectively. The acetone extracts didn' t show any notable inhibition. The presence of free amino acids like lysine, aspartic acid, glutamic acid, arginine etc., terpenoids and pigents were confirmed through HPTLC analysis. The presence of siloxanes and propanoic acid were also revealed through GC-MS. Conclusions: This study suggests that further scrutinisation of the B. leachii, K. ornata and Aplysia sp. will pave the way for development of antibacterial and α-amylase inhibitory agent for therapeutic application.

  8. In vitro antibacterial, alpha-amylase inhibition potential of three nudibranchs extracts from South East coast of India

    Directory of Open Access Journals (Sweden)

    Giji Sadhasivam

    2013-10-01

    Full Text Available Objective: To study the antibacterial and antiamylase properties of methanol and acetone extracts of nudibranchs including Bursatella leachii (B. leachii, Kalinga ornata (K. ornata, Aplysia sp. Methods: Crude methanol and acetone extracts of sea slugs were tested for inhibition of fish bacterial pathogens' growth through disc diffusion method. The activity was measured based on the formation of inhibition zone around the disc impregnated with crude extracts. The α-amylase inhibitory effect was also measured calorimetrically. The chemical fingerprinting of the extract was recorded with HPTLC and GC-MS. Results: The solvent extracts of all the three sea slugs showed antibacterial property. The maximum zone of inhibition (>15-20 mm was recorded for methanol and acetone extracts of K. ornata. The methanol extract of Aplysia sp. exhibited 93% inhibition against α-amylase, following by B. leachii (methanol 70.6% and K. ornata (methanol 49.03% inhibition respectively. The acetone extracts didn' t show any notable inhibition. The presence of free amino acids like lysine, aspartic acid, glutamic acid, arginine etc., terpenoids and pigents were confirmed through HPTLC analysis. The presence of siloxanes and propanoic acid were also revealed through GC-MS. Conclusions: This study suggests that further scrutinisation of the B. leachii, K. ornata and Aplysia sp. will pave the way for development of antibacterial and α-amylase inhibitory agent for therapeutic application.

  9. Influence of different prostaglandin applications on cervical rheology.

    Science.gov (United States)

    Spätling, L; Neuman, M R; Huch, R; Huch, A

    1985-10-01

    The softening effect of prostaglandin (PG) on cervical tissue prior to elective pregnancy termination is quantified by a new technique for the measurement of the elastance and relaxation of the cervix. The method is based on the pressure-volume relation of a compliant balloon placed in the cervical canal. These properties have been measured before and after different applications of prostaglandins in 58 patients electively terminating pregnancy. Application techniques used included high pressure jet application of PGE2 into the tissue of the portio uteri and the internal cervical os (120 micrograms), PGE2 and PGF2 alpha in Tylose gel (100 micrograms/0.5 ml); PGE2 as an intracervical tablet (150 micrograms) and PGE2 oral tablets placed into the posterior fornix of the vagina. Significant changes in cervical elastance were seen with the intracervically applied PGE2 in Tylose gel and the vaginally applied PGE2 tablets. The intracervically applied PGE2 gel also gave significant changes in cervical relaxation. No side effects other than mild cramping (2 patients) were seen with any of the applications in this study.

  10. Requirement of cyclooxygenase-2 expression and prostaglandins for human prostate cancer cell invasion.

    Science.gov (United States)

    Nithipatikom, Kasem; Isbell, Marilyn A; Lindholm, Paul F; Kajdacsy-Balla, Andre; Kaul, Sushma; Campell, William B

    2002-01-01

    The PC-3 Low Invasive cells and the PC-3 High Invasive cells were used to investigate the correlation of the COX-2 expression and its arachidonic acid metabolites, prostaglandins, with their invasiveness through Matrigel using a Boyden chamber assay. The COX-2 expression in PC-3 High Invasive cells was approximately 3-fold higher than in PC-3 Low Invasive cells while the COX-1 expression was similar in both cell sublines. When incubated with arachidonic acid, PGE2 was the major prostaglandin produced by these cells. PC-3 High Invasive cells produced PGE2 approximately 2.5-fold higher than PC-3 Low Invasive cells. PGD2 was the second most abundant prostaglandin produced by these cells. Both indomethacin (a nonspecific COX inhibitor) and NS-398 (a specific COX-2 inhibitor) inhibited the production of prostaglandins and the cell invasion. PGE2 alone did not induce the cell invasion of PC-3 Low Invasive cells. However, PGE2 reversed the inhibition of cell invasion by NS-398 and enhanced the cell invasion of the PC-3 High Invasive cells. In contrast, PGD2 slightly inhibited the cell invasion. These results suggest that in the PC-3 Low Invasive cells, COX-2-derived PGE2 may not be sufficient to induce cell invasion while in the PC-3 High Invasive cells, PGE2 may be sufficient to act as an enhancer for the cell invasion. Further, PGD2 may represent a weak inhibitor and counteracts the effect of PGE2 in the cell invasion.

  11. Prostaglandin cyclooxygenase products but not thromboxane A2 are involved in the pathogenesis of ewthromelalgia in thrombocythaemia

    Directory of Open Access Journals (Sweden)

    J. J. Michiels

    1993-01-01

    Full Text Available Fluid of artificial blisters from erythromelalgic skin areas in primary thrombocythaemia contained a high amount of prostaglandin-E-like activity. Dazoxiben did not alleviate the erythromelalgia in patients with primary thrombocythaemia despite complete inhibition of platelet malondialdehyde and thromboxane B2 synthesis and no inhibition of prostaglandin-E-like material. During a 10-day dazoxiben treatment period, persistent erythromelalgia was associated with a significant shortened mean platelet life span of 3.2 days. During subsequent treatment with low dose acetylsalicylic acid daily complete relief of erythromelalgia was associated with inhibition of platelet prostaglandin endoperoxide production and correction of platelet mean life span to normal, 7.9 days. These observations indicate that prostaglandin E2, or another prostaglandin endoperoxide metabolite, is involved in the pathogenesisof erythromelalgia. The presented study does not give one single clue as to the origin (platelet, vessel wall or other of the prostanoid, but very likely originates from platelets because a very low dose of acetylsalicylic acid (250 to 500 mg every other day, which irreversibly inhibits platelet cyclooxygenase, is highly effective in the prevention of erythromelalgia in thrombocythaemia.

  12. Bone formation induced in an infant by systemic prostaglandin-E2 administration

    DEFF Research Database (Denmark)

    Jørgensen, H R; Svanholm, H; Høst, A

    1988-01-01

    We report a case of long-term systemic administration of prostaglandin E2 (PGE2) to a newborn infant with ductus-dependent congenital heart disease. After 46 days of treatment, radiography showed cortical hyperostosis of the long bones. The child died 62 days after discontinuation of prostaglandin...

  13. Biosynthesis of prostaglandins in gingiva of patients with chronic periodontitis

    Energy Technology Data Exchange (ETDEWEB)

    Mendieta, C.F.; Reeve, C.M.; Romero, J.C.

    1985-01-01

    This study was undertaken to determine the ability of inflamed and normal gingival tissues to synthesize prostaglandins (PGs) from the precursor arachidonic acid. Thirteen samples of inflamed human gingival tissue and six samples of normal human gingival tissue were studied. The inflammation was characterized histologically. After incubation of the tissue with (/sup 14/C)arachidonate, PG metabolites were separated by thin-layer chromatography and identified by comparison with co-chromatographed standards. Inflamed gingival tissue synthesized significantly larger amounts, compared to normal tissue, of 6-keto-PGF1 alpha (P less than 0.05), thromboxane B2, PGD2, and PGA2. Some unidentified metabolites, possibly lipoxygenase products were detected in significantly larger amounts in inflamed than in normal tissue.

  14. Regulation of metalloproteinases and NF-kappaB activation in rabbit synovial fibroblasts via E prostaglandins and Erk: contrasting effects of nabumetone and 6MNA.

    Science.gov (United States)

    Pillinger, Michael H; Dinsell, Victoria; Apsel, Beth; Tolani, Sonia N; Marjanovic, Nada; Chan, Edwin S L; Gomez, Paul; Clancy, Robert; Chang, Lih-Fan; Abramson, Steven B

    2004-07-01

    1 Nabumetone is a prodrug that is converted in vivo into 6-methoxy-2-naphthylacetic acid (6MNA), a cyclooxygenase inhibitor with anti-inflammatory properties. We tested the effects of nabumetone and 6MNA on the inflammatory responses of synovial fibroblasts (SFs). 2 Brief exposures to 6MNA (50-150 microm) had no effect on IL-1beta/TNF-alpha (each 20 ng ml(-1))-stimulated Erk activation. Longer exposures depleted prostaglandin E1 (PGE1) as much as 70%, and stimulated Erk as much as 300%. Nabumetone (150 microm) inhibited Erk activation by 60-80%. 6MNA (50-150 microm) stimulated (approximately 200%) and nabumetone (150 microm) inhibited (approximately 50%) matrix metalloproteinase (MMP)-1, but not MMP-13 secretion from SFs. 3 6MNA stimulation of MMP-1 secretion was inhibited approximately 30% by PGE1 (1 microm) and approximately 80% by the Erk pathway inhibitor UO126 (10 microm), confirming that PGE depletion and Erk activation mediate MMP-1 secretion by 6MNA. 4 Consistent with its role as an Erk inhibitor, nabumetone (150 microm) abrogated 6MNA enhancement of MMP-1 secretion. 5 UO126 (10 microm) and nabumetone (150 microm) inhibited (approximately 70 and 40%, respectively), but 6MNA (150 microm) enhanced (approximately 40%), NF-kappaB activation. 6 Our data indicate that 6MNA shares with other COX inhibitors several proinflammatory effects on synovial fibroblasts. In contrast, nabumetone demonstrates anti-inflammatory and potentially arthroprotective effects that have not been previously appreciated.

  15. Preintegration HIV-1 inhibition by a combination lentiviral vector containing a chimeric TRIM5 alpha protein, a CCR5 shRNA, and a TAR decoy.

    Science.gov (United States)

    Anderson, Joseph S; Javien, John; Nolta, Jan A; Bauer, Gerhard

    2009-12-01

    Human immunodeficiency virus (HIV) gene therapy offers a promising alternative approach to current antiretroviral treatments to inhibit HIV-1 infection. Various stages of the HIV life cycle including pre-entry, preintegration, and postintegration can be targeted by gene therapy to block viral infection and replication. By combining multiple highly potent anti-HIV transgenes in a single gene therapy vector, HIV-1 resistance can be achieved in transduced cells while prohibiting the generation of escape mutants. Here, we describe a combination lentiviral vector that encodes three highly effective anti-HIV genes functioning at separate stages of the viral life cycle including a CCR5 short hairpin RNA (shRNA) (pre-entry), a human/rhesus macaque chimeric TRIM5 alpha (postentry/preintegration), and a transactivation response element (TAR) decoy (postintegration). The major focus on designing this anti-HIV vector was to block productive infection of HIV-1 and to inhibit any formation of provirus that would maintain the viral reservoir. Upon viral challenge, potent preintegration inhibition of HIV-1 infection was achieved in combination vector-transduced cells in both cultured and primary CD34(+) hematopoietic progenitor cell (HPC)-derived macrophages. The generation of escape mutants was also blocked as evaluated by long-term culture of challenged cells. The ability of this combination anti-HIV lentiviral vector to prevent HIV-1 infection, in vitro, warrants further evaluation of its in vivo efficacy.

  16. Madecassoside Inhibits Melanin Synthesis by Blocking Ultraviolet-Induced Inflammation

    Directory of Open Access Journals (Sweden)

    Eunsun Jung

    2013-12-01

    Full Text Available Madecassoside (MA, a pentacyclic triterpene isolated from Centella asitica (L., is used as a therapeutic agent in wound healing and also as an anti-inflammatory and anti-aging agent. However, the involvement of MA in skin-pigmentation has not been reported. This study was conducted to investigate the effects of MA on ultraviolet (UV-induced melanogenesis and mechanisms in a co-culture system of keratinocytes and melanocytes. MA significantly inhibited UVR-induced melanin synthesis and melanosome transfer in the co-culture system. These effects were further demonstrated by the MA-induced inhibition of protease-activated receptor-2 expression and its signaling pathway, cyclooxygenase-2, prostaglandin E2 and prostaglandin F2 alpha in keratinocytes. The clinical efficacy of MA was confirmed on artificially tanned human skin. MA significantly reduced UV-induced melanin index at 8 weeks after topical application. Overall, the study demonstrated significant benefits of MA use in the inhibition of hyperpigmentation caused by UV irradiation.

  17. Comparative Analysis of Ocimum basilicum and Ocimum sanctum: Extraction Techniques and Urease and alpha-Amylase inhibition

    Directory of Open Access Journals (Sweden)

    *S. Khair-ul-Bariyah

    2012-09-01

    Full Text Available In the present work, two important medicinal plants of genus Ocimum, O. basilicum and O.sanctum have been compared in a number of phytochemical parameters. Effect of extraction techniques, solvent extraction, Soxhlet extraction and hydro-distillation, on the yield in different solvents have been investigated. Hydro-distillation gave a better yield of more volatile components than hexane fraction of the other two techniques. Both the plants showed good urease inhibitory activity. Hydro-distillate was stronger inhibitor than hexane or methanolic extracts of solvent or Soxhlet extractions. The extracts of O. basilicumshowed a greater urease activity than extracts of O. sanctum.Alpha-amylase inhibitory activity of O. basilicum was also higher than that of O. sanctum. Notably, the synergistic effect of the extracts of the two plants was much higher than their individual efficacy against alpha-amylase. The activity decreased with decrease in concentration. Both the species had almost equal air pollution tolerance index (APTI with O. basilicum(10.558 having slightly higher value than O. sanctum (9.202.Both plants contained alkaloids and phenolics. Both the plants also had almost same nutritional values.

  18. Acrolein with an alpha, beta-unsaturated Carbonyl Group Inhibits LPS-induced Homodimerization of Toll-like Receptor 4

    Science.gov (United States)

    Acrolein is a highly electrophilic a,ß-unsaturated aldehyde present in a number of environmental sources, especially cigarette smoke. It reacts strongly with the thiol groups of cysteine residues by Michael addition and has been reported to inhibit nuclear factor-kB (NF-kB) activation by lipopolysac...

  19. Anti-inflammatory activity of Chios mastic gum is associated with inhibition of TNF-alpha induced oxidative stress

    Directory of Open Access Journals (Sweden)

    Lerakis Stamatios

    2011-06-01

    Full Text Available Abstract Background Gum of Chios mastic (Pistacia lentiscus var. chia is a natural antimicrobial agent that has found extensive use in pharmaceutical products and as a nutritional supplement. The molecular mechanisms of its anti-inflammatory activity, however, are not clear. In this work, the potential role of antioxidant activity of Chios mastic gum has been evaluated. Methods Scavenging of superoxide radical was investigated by electron spin resonance and spin trapping technique using EMPO spin trap in xanthine oxidase system. Superoxide production in endothelial and smooth muscle cells stimulated with TNF-α or angiotensin II and treated with vehicle (DMSO or mastic gum (0.1-10 μg/ml was measured by DHE and HPLC. Cellular H2O2 was measured by Amplex Red. Inhibition of protein kinase C (PKC with mastic gum was determined by the decrease of purified PKC activity, by inhibition of PKC activity in cellular homogenate and by attenuation of superoxide production in cells treated with PKC activator phorbol 12-myristate 13-acetate (PMA. Results Spin trapping study did not show significant scavenging of superoxide by mastic gum itself. However, mastic gum inhibited cellular production of superoxide and H2O2 in dose dependent manner in TNF-α treated rat aortic smooth muscle cells but did not affect unstimulated cells. TNF-α significantly increased the cellular superoxide production by NADPH oxidase, while mastic gum completely abolished this stimulation. Mastic gum inhibited the activity of purified PKC, decreased PKC activity in cell homogenate, and attenuated superoxide production in cells stimulated with PKC activator PMA and PKC-dependent angiotensin II in endothelial cells. Conclusion We suggest that mastic gum inhibits PKC which attenuates production of superoxide and H2O2 by NADPH oxidases. This antioxidant property may have direct implication to the anti-inflammatory activity of the Chios mastic gum.

  20. Pro-cognitive and antipsychotic efficacy of the alpha7 nicotinic partial agonist SSR180711 in pharmacological and neurodevelopmental latent inhibition models of schizophrenia.

    Science.gov (United States)

    Barak, Segev; Arad, Michal; De Levie, Amaya; Black, Mark D; Griebel, Guy; Weiner, Ina

    2009-06-01

    Schizophrenia symptoms can be segregated into positive, negative and cognitive, which exhibit differential sensitivity to drug treatments. Accumulating evidence points to efficacy of alpha7 nicotinic receptor (nAChR) agonists for cognitive deficits in schizophrenia but their activity against positive symptoms is thought to be minimal. The present study examined potential pro-cognitive and antipsychotic activity of the novel selective alpha7 nAChR partial agonist SSR180711 using the latent inhibition (LI) model. LI is the reduced efficacy of a previously non-reinforced stimulus to gain behavioral control when paired with reinforcement, compared with a novel stimulus. Here, no-drug controls displayed LI if non-reinforced pre-exposure to a tone was followed by weak but not strong conditioning (2 vs 5 tone-shock pairings). MK801 (0.05 mg/kg, i.p.) -treated rats as well as rats neonatally treated with nitric oxide synthase inhibitor L-NoArg (10 mg/kg, s.c.) on postnatal days 4-5, persisted in displaying LI with strong conditioning, whereas amphetamine (1 mg/kg) -treated rats failed to show LI with weak conditioning. SSR180711 (0.3, 1, 3 mg/kg, i.p.) was able to alleviate abnormally persistent LI produced by acute MK801 and neonatal L-NoArg; these models are believed to model cognitive aspects of schizophrenia and activity here was consistent with previous findings with alpha7-nAChR agonists. In addition, unexpectedly, SSR180711 (1, 3 mg/kg, i.p.) potentiated LI with strong conditioning in no-drug controls and reversed amphetamine-induced LI disruption, two effects considered predictive of activity against positive symptoms of schizophrenia. These findings suggest that SSR180711 may be beneficial not only for the treatment of cognitive symptoms in schizophrenia, as reported multiple times previously, but also positive symptoms.

  1. Role of prostaglandins in development of porcine blastocysts.

    Science.gov (United States)

    Geisert, R D; Rasby, R J; Minton, J E; Wetteman, R P

    1986-02-01

    Rapid elongation of porcine blastocysts between Days 11 to 12 of pregnancy coincides with an increase in uterine luminal content of prostaglandins. The present study evaluated the effect of two prostaglandin synthesis inhibitors (indomethacin and flunixin meglumine) on elongation of porcine blastocysts from spherical to filamentous forms between Day 11 to 12 of pregnancy. Gilts were hemi-hysterectomized on Day 11 of pregnancy. The excised uterine horn was flushed with 0.9% saline and diameter of blastocysts recovered were measured. Immediately following surgery, pregnant gilts were assigned to receive either: 1) vehicle every 4 h, 2) flunixin meglumine (banamine) every 4 h, or 3) indomethacin every 12 h. The remaining uterine horn was removed and flushed after the time of blastocyst elongation estimated for each gilt on basis of blastocyst development in the first horn. Uterine flushings were analyzed for total calcium, protein, acid phosphatase activity, estrone, estradiol-17 beta and prostaglandin F. Pretreatment blastocyst diameter was similar for all groups and ranged from 1 mm to 20 mm. Treatment of gilts with either banamine or indomethacin effectively inhibited (P less than 0.001) the increase in uterine luminal content of PGF. Total calcium, estrone and estradiol-17 beta were not influenced by treatment. Total uterine luminal protein and acid phosphatase activity were reduced (P less than 0.05) in banamine treated gilts compared to those receiving vehicle or indomethacin treatments. Although total PGF recovered in uterine flushings was reduced during the period of blastocyst elongation, treatment with PGF synthetase inhibitors failed to block rapid elongation of blastocysts from the spherical to filamentous forms.

  2. Preparation for induction of labour of the unfavourable cervix with Foley catheter compared with vaginal prostaglandin.

    Science.gov (United States)

    Thomas, I L; Chenoweth, J N; Tronc, G N; Johnson, I R

    1986-02-01

    Ripening of the unfavourable cervix prior to induction of labour using traction on a Foley catheter (32 patients) was compared with 40 mg of prostaglandin F2 alpha in Tylose gel applied to the external cervical os and held in place for 12 hours with a vaginal diaphragm (25 patients). Each patient in the above groups had a modified Bishop score of 0-3 and was randomly allocated to one or other group. Comparison was made with a further 25 patients in whom the cervical score was 4-6. Timing of amniotomy and commencement of Syntocinon infusion were equivalent for all patients. Prostaglandins conferred no advantage over Foley catheter in terms of amniotomy-delivery interval, operative delivery rate, and condition of the baby one minute after birth. The disadvantages of prostaglandins for cervical ripening are a longer preparation-delivery interval, and cost ($77 versus $4.75 for the Foley catheter). Currently, prostaglandins are not officially approved for use in Australia for induction of labour. It is suggested, therefore, that the Foley catheter is preferable for ripening the unfavourable cervix as a prelude to amniotomy.

  3. R-alpha-methylhistamine-induced inhibition of gastric acid secretion in pylorus-ligated rats via central histamine H3 receptors.

    Science.gov (United States)

    Barocelli, E; Ballabeni, V; Chiavarini, M; Impicciatore, M

    1995-08-01

    1. The effect of central H3 histamine receptor activation on gastric acid and pepsin production has been investigated in pylorus-ligated rats. 2. Intracerebroventricular injections (i.c.v.) of the selective H3 agonist, R-alpha-methylhistamine (0.5-50 nmol per rat) caused a dose-dependent inhibition of gastric acid secretion while intravenous administration (5-500 nmol per rat) was completely ineffective. 3. I.c.v. microinjections of mepyramine, tiotidine and thioperamide (51 nmol per rat), selective antagonists at H1-, H2- and H3-sites respectively, failed to modify the acid secretory response to pylorus ligation. 4. The antisecretory effect of R-alpha-methylhistamine (5 nmol per rat, i.c.v.) was selectively prevented by the H3-blocker, thioperamide (51 nmol per rat, i.c.v.), mepyramine and tiotidine pretreatment being completely inactive. 5. Unlike acid secretion, pepsin production was not significantly affected by all the tested compounds. 6. These findings provide the first pharmacological evidence that the activation of central H3 histamine receptors exerts a negative control in the regulation of gastric acid secretion in conscious pylorus-ligated rats.

  4. Lateralisation effect in comprehension of emotional facial expression: a comparison between EEG alpha band power and behavioural inhibition (BIS) and activation (BAS) systems.

    Science.gov (United States)

    Balconi, Michela; Mazza, Guido

    2010-05-01

    Asymmetry in comprehension of facial expression of emotions was explored in the present study by analysing alpha band variation within the right and left cortical sides. Second, the behavioural activation system (BAS) and behavioural inhibition system (BIS) were considered as an explicative factor to verify the effect of a motivational/emotional variable on alpha activity. A total of 19 participants looked at an ample range of facial expressions of emotions (anger, fear, surprise, disgust, happiness, sadness, and neutral) in random order. The results demonstrated that anterior frontal sites were more active than central and parietal sites in response to facial stimuli. Moreover, right and left side responses varied as a function of emotional types, with an increased right frontal activity for negative, aversive emotions vs an increased left response for positive emotion. Finally, whereas higher BIS participants generated more right hemisphere activation for some negative emotions (such as fear, anger, surprise, and disgust), BAS participants were more responsive to positive emotion (happiness) within the left hemisphere. Motivational significance of facial expressions was considered to elucidate cortical differences in participants' responses to emotional types.

  5. Yohimbine increases submaxillary kallikrein release into the saliva in dogs: evidence for alpha 2-adrenoceptor-mediated inhibition of cholinergic pathways.

    Science.gov (United States)

    Girolami, J. P.; Bascands, J. L.; Pécher, C.; Berlan, M.; Montastruc, J. L.; Montastruc, P.

    1991-01-01

    1. The effects of the alpha 2-adrenoceptor antagonist, yohimbine (0.5 mg kg-1, i.v.) on basal, sympathetic and parasympathetic stimulation-induced submaxillary kallikrein release were investigated in the anaesthetized dog. Kallikrein was measured by its kininogenase activity before and after trypsin activation which also allowed a study of the proportion of active to total enzyme. 2. Yohimbine induced a rapid, three fold increase in basal kallikrein release correlated with an increase in salivary flow rate which lasted for 60 min following injection. 3. Sectioning the chorda tympani did not affect basal kallikrein release but abolished yohimbine-induced rise in salivary kallikrein secretion. 4. Parasympathetic stimulation alone induced a 3 to 4 fold increase in basal kallikrein release correlated with an increase in salivary flow rate. Yohimbine induced a significant additional increase in parasympathetic-stimulated kallikrein release. 5. When the cervical sympathetic nerve was sectioned the basal kallikrein release decreased by 30 to 40%. 6. Sympathetic stimulation alone also induced a 3 to 4 fold increase in basal kallikrein. This was not correlated with the salivary flow and unaffected by yohimbine. 7. The results indicate that yohimbine increases submaxillary kallikrein release into the saliva by inhibition of presynaptic alpha 2-adrenoceptors located on the chorda tympani nerve endings. PMID:1849766

  6. alpha-Lipoic acid supplementation inhibits oxidative damage, accelerating chronic wound healing in patients undergoing hyperbaric oxygen therapy.

    Science.gov (United States)

    Alleva, Renata; Nasole, Emanuele; Di Donato, Ferruccio; Borghi, Battista; Neuzil, Jiri; Tomasetti, Marco

    2005-07-29

    Hyperbaric oxygen (HBO) therapy is successfully used for the treatment of a variety of conditions. However, prolonged exposure to high concentrations of oxygen induces production of reactive oxygen species, causing damage to the cells. Thus, antioxidant supplementation has been proposed as an adjuvant to attenuate such deleterious secondary effects. We evaluated the effects of alpha-lipoic acid (LA) in patients affected by chronic wounds undergoing HBO treatment. LA supplementation efficiently reduces both the lipid and DNA oxidation induced by oxygen exposure. LA exerted its antioxidant activity by directly interacting with free radicals or by recycling vitamin E. An inhibitory effect of LA on the pro-inflammatory cytokine interleukin-6 was observed. Taken together, we demonstrated an adjuvant effect of LA in HBO therapy used for impaired wound healing treatment. We propose that LA may be used to further promote the beneficial effects of HBO therapy.

  7. Preferential binding of growth inhibitory prostaglandins by the target protein of a carcinogen

    Energy Technology Data Exchange (ETDEWEB)

    Khan, S.H.; Sorof, S. (Fox Chase Cancer Center, Philadelphia, PA (United States))

    1990-12-01

    Liver fatty acid binding protein (L-FABP) is the principal target protein of the hepatic carcinogen N-(2-fluorenyl)acetamide (2-acetylaminofluorene) in rat liver. In addition, the cyclopentenone prostaglandins (PG), PGA, PGJ{sub 2}, and {Delta}{sup 12}-PGJ{sub 2}, inhibit the growth of many cell types in vitro. This report describes the preferential binding of the growth inhibitory prostaglandins by L-FABP and the reversible inhibition of thymidine incorporation into DNA by PGA{sub 2} and {Delta}{sup 12}-PGJ{sub 2} in primary cultures of purified rat hepatocytes. As a model ligand, ({sup 3}H)PGA{sub 1} bound to L-FABP specifically, reversibly, rapidly, and with high affinity. Its dissociation constants were 134 nM (high affinity) and 3.6 {mu}M (low affinity). The high-affinity finding of ({sup 3}H)PGA{sup 1} correlated with their growth inhibitory activities reported previously and here. The in vitro actions of L-FABP are compatible with those of a specific and dissociable carrier of growth inhibitory prostaglandins in rat hepatocytes and suggest that the carcinogen may usurp the cellular machinery of the growth inhibitory prostaglandins.

  8. Inhibition of the alpha- and beta-carbonic anhydrases from the gastric pathogen Helycobacter pylori with anions.

    Science.gov (United States)

    Maresca, Alfonso; Vullo, Daniela; Scozzafava, Andrea; Supuran, Claudiu T

    2013-04-01

    The gastric pathogen Helicobacter pylori encodes two carbonic anhydrases (CAs, EC 4.2.1.1), an α- and a β-class one, hpαCA and hpβCA, crucial for its survival in the acidic environment from the stomach. Sulfonamides, strong inhibitors of these enzymes, block the growth of the pathogen, in vitro and in vivo. Here we report the inhibition of the two H. pylori CAs with inorganic and complex anions and other molecules interacting with zinc proteins. hpαCA was inhibited in the low micromolar range by diethyldithiocarbamate, sulfamide, sulfamic acid, phenylboronic acid, and in the submillimolar one by cyanide, cyanate, hydrogen sulfide, divanadate, tellurate, perruthenate, selenocyanide, trithiocarbonate, iminodisulfonate. hpβCA generally showed a stronger inhibition with most of these anions, with several low micromolar and many submillimolar inhibitors detected. These inhibitors may be used as leads for developing anti-H. pylori agents with a diverse mechanism of action compared to clinically used antibiotics.

  9. Growth Inhibition and Apoptosis Induced by Retinoic Acid Combined with Interferon Alpha-2a on Transitional Cell Carcinoma of Bladder

    Institute of Scientific and Technical Information of China (English)

    QIANLi-xin; LIUXun-liang; ZHOUJian-wei; MonicaLiebert; ZOUChang-chun; ZOUChang-ping

    2004-01-01

    To identify new favorable agents and develop novel approaches for the chemoprevention and treatment of superficial bladder cancer and invesligate the effects of combination of relinoids and interferon α-2a on growth inhibition and apoptosis induction in bladder cancer cell lines. Methods: Four bladder cancer cell lines, grade 1 to 3,and two retinoids, all-trans-retinoic acid(ATRA) ,9.cis retinoic acid(9cRA) ,combined with inteferon α-2a(INF),were used in the study.We compared the competence of these agents to inhibit growth, induce apoptosis, affect the exptession of nuclear retinoid receptors, and modulate STAT1 protein. Resu/ts: Most of the bladder cancer cell lines were resistant to the effect of ATRA and 9cRA on growth inhibition and apoptosis induction, even at higher concentration (10-5M).The effects of ATRA and 9c RA on cell growth and apoptosis were enhanced by INF α-2a.Combination of ATRA and IFNa-2a induced ~ and Slat 1 expression in three bladder cancer cell lines, ~: The results demonstrated that INFw2a synergize with the inhibitory effect of ATRA and 9c RA on the growth intn'bition and apoptosis of bladder cancer cells in vitro, which suggested that it has a potenlJal intexest for the trealment of transitimml cell carcinmna of bladder.

  10. Hispolon inhibits the growth of estrogen receptor positive human breast cancer cells through modulation of estrogen receptor alpha

    Energy Technology Data Exchange (ETDEWEB)

    Jang, Eun Hyang; Jang, Soon Young; Cho, In-Hye [Department of Pharmacy, Graduate School, Kyung Hee University, 26 Kyungheedae-ro, Dongdaemun-gu, Seoul 130-701 (Korea, Republic of); Hong, Darong [Department of Life and Nanopharmaceutical Science, Graduate School, Kyung Hee University, 26 Kyungheedae-ro, Dongdaemun-gu, Seoul 130-701 (Korea, Republic of); Jung, Bom; Park, Min-Ju [Department of Pharmacy, Graduate School, Kyung Hee University, 26 Kyungheedae-ro, Dongdaemun-gu, Seoul 130-701 (Korea, Republic of); Kim, Jong-Ho, E-mail: jonghokim@khu.ac.kr [Department of Pharmacy, Graduate School, Kyung Hee University, 26 Kyungheedae-ro, Dongdaemun-gu, Seoul 130-701 (Korea, Republic of)

    2015-08-07

    Human estrogen receptor α (ERα) is a nuclear transcription factor that is a major therapeutic target in breast cancer. The transcriptional activity of ERα is regulated by certain estrogen-receptor modulators. Hispolon, isolated from Phellinus linteus, a traditional medicinal mushroom called Sanghwang in Korea, has been used to treat various pathologies, such as inflammation, gastroenteric disorders, lymphatic diseases, and cancers. In this latter context, Hispolon has been reported to exhibit therapeutic efficacy against various cancer cells, including melanoma, leukemia, hepatocarcinoma, bladder cancer, and gastric cancer cells. However, ERα regulation by Hispolon has not been reported. In this study, we investigated the effects of Hispolon on the growth of breast cancer cells. We found that Hispolon decreased expression of ERα at both mRNA and the protein levels in MCF7 and T47D human breast cancer cells. Luciferase reporter assays showed that Hispolon decreased the transcriptional activity of ERα. Hispolon treatment also inhibited expression of the ERα target gene pS2. We propose that Hispolon, an anticancer drug extracted from natural sources, inhibits cell growth through modulation of ERα in estrogen-positive breast cancer cells and is a candidate for use in human breast cancer chemotherapy. - Highlights: • Hispolon decreased ERα expression at both mRNA and protein levels. • Hispolon decreased ERα transcriptional activity. • Hispolon treatment inhibited expression of ERα target gene pS2. • Shikonin is a candidate chemotherapeutic target in the treatment of human breast cancer.

  11. p-Benzoquinone, a reactive metabolite of benzene, prevents the processing of pre-interleukins-1{alpha} and -1{beta} to active cytokines by inhibition of the processing enzymes, calpain, and interleukin-1{beta} converting enzyme

    Energy Technology Data Exchange (ETDEWEB)

    Kalf, G.F.; Renz, J.F.; Niculescu, R. [Thomas Jefferson Univ., Philadelphia, PA (United States)

    1996-12-01

    Chronic exposure of humans to benzene affects hematopoietic stem and progenitor cells and leads to aplastic anemia. The stromal macrophage, a target of benzene toxicity, secretes interieukin-1 (IL-1), which induces the stromal fibroblast to synthesize hematopoietic colony-stimulating factors. In a mouse model, benzene causes an acute marrow hypocellularity that can be prevented by the concomitant administration of IL-1{alpha}. The ability of benzene to interfere with the production and secretion of IL-1{alpha} was tested. Stromal macrophages from benzene-treated mice were capable of the transcription of the IL-1{alpha} gene and the translation of the message but showed an inability to process the 34-kDa pre-IL-1{alpha} precursor to the 17-kDa biologically active cytokine. Treatment of normal murine stromal macrophages in culture with hydroquinone (HQ) also showed an inhibition in processing of pre-IL-1{alpha}. Hydroquinone is oxidized by a peroxidase-mediated reaction in the stromal macrophage to p-benzoquinone, which interacts with the sulfhydryl (SH) groups of proteins and was shown to completely inhibit the activity of calpain, the SH-dependent protease that cleaves pre-IL-1{alpha}. In a similar manner, HQ, via peroxidase oxidation to p-benzoquinone, was capable of preventing the IL-1{beta} autocrine stimulation of growth of human B1 myeloid tumor cells by preventing the processing of pre-IL-1{beta} to mature cytokine. Benzoquinone was also shown to completely inhibit the ability of the SH-dependent IL-1{beta} converting enzyme. Thus benzene-induced bone marrow hypocellularity may result from apoptosis of hematopoietic progenitor cells brought about by lack of essential cylokines and deficient IL-1{alpha} production subsequent to the inhibition of calpain by p-benzoquinone and the prevention of pre-IL-1 processing. 34 refs., 8 figs.

  12. Antioxidant rich grape pomace extract suppresses postprandial hyperglycemia in diabetic mice by specifically inhibiting alpha-glucosidase

    Directory of Open Access Journals (Sweden)

    Hogan Shelly

    2010-08-01

    Full Text Available Abstract Background Postprandial hyperglycemia is an early defect of type 2 diabetes and one of primary anti-diabetic targets. Treatment of postprandial hyperglycemia can be achieved by inhibiting intestinal α-glucosidase, the key enzyme for oligosaccharide digestion and further glucose absorption. Grape pomace is winemaking byproduct rich in bioactive food compounds such as phenolic antioxidants. This study evaluated the anti-diabetic potential of two specific grape pomace extracts by determining their antioxidant and anti-postprandial hyperglycemic activities in vitro and in vivo. Methods The extracts of red wine grape pomace (Cabernet Franc and white wine grape pomace (Chardonnay were prepared in 80% ethanol. An extract of red apple pomace was included as a comparison. The radical scavenging activities and phenolic profiles of the pomace extracts were determined through the measurement of oxygen radical absorbance capacity, DPPH radical scavenging activity, total phenolic content and flavonoids. The inhibitory effects of the pomace extracts on yeast and rat intestinal α-glucosidases were determined. Male 6-week old C57BLKS/6NCr mice were treated with streptozocin to induce diabetes. The diabetic mice were then treated with vehicle or the grape pomace extract to determine whether the oral intake of the extract can suppress postprandial hyperglycemia through the inhibition of intestinal α-glucosidases. Results The red grape pomace extract contained significantly higher amounts of flavonoids and phenolic compounds and exerted stronger oxygen radical absorbance capacity than the red apple pomace extract. Both the grape pomace extracts but not the apple pomace extract exerted significant inhibition on intestinal α-glucosidases and the inhibition appears to be specific. In the animal study, the oral intake of the grape pomace extract (400 mg/kg body weight significantly suppressed the postprandial hyperglycemia by 35% in streptozocin

  13. Alpha Interferon Inhibits Human Herpesvirus 8 (HHV-8) Reactivation in Primary Effusion Lymphoma Cells and Reduces HHV-8 Load in Cultured Peripheral Blood Mononuclear Cells

    Science.gov (United States)

    Monini, Paolo; Carlini, Francesca; Stürzl, Michael; Rimessi, Paola; Superti, Fabiana; Franco, Marina; Melucci-Vigo, Gianna; Cafaro, Aurelio; Goletti, Delia; Sgadari, Cecilia; Butto’, Stefano; Leone, Patrizia; Leone, Pasqualina; Chiozzini, Chiara; Barresi, Caterina; Tinari, Antonella; Bonaccorsi, Angela; Capobianchi, Maria R.; Giuliani, Massimo; di Carlo, Aldo; Andreoni, Massimo; Rezza, Giovanni; Ensoli, Barbara

    1999-01-01

    Infection by human herpesvirus 8 (HHV-8) is associated with the development of Kaposi’s sarcoma (KS). Since regression of KS can be achieved by treatment of the patients with alpha interferon (IFN-α), we analyzed the effects of IFN-α or anti-IFN-α antibodies (Ab) on HHV-8 latently infected primary effusion lymphoma-derived cell lines (BCBL-1 and BC-1) and on peripheral blood mononuclear cells (PBMC) from patients with all forms of KS and from at-risk subjects. IFN-α inhibited in a dose-dependent manner the amplification of HHV-8 DNA in BCBL-1 cells induced to lytic infection with tetradecanoyl phorbol acetate (TPA). This effect was associated with the inhibition of the expression of HHV-8 nut-1 and kaposin genes that are induced early and several hours, respectively, after TPA treatment. In addition, IFN-α inhibited virus production and/or release from BCBL-1 cells. Inhibition of nut-1 and kaposin genes by IFN-α was also observed in BC-1 cells induced with n-butyrate. Conversely, the addition of anti-IFN-α Ab to TPA-induced BCBL-1 cells resulted in a larger number of mature enveloped particles and in a more extensive cytopathic effect due to the neutralization of the endogenous IFN produced by these cells. IFN was also produced by cultured PBMC from HHV-8-infected individuals, and this was associated with a loss of viral DNA during culture. However, the addition of anti-IFN-α Ab or anti-type I IFN receptor Ab promoted the maintenance of HHV-8 DNA in these cells that was associated with the detection of the latency-associated kaposin RNA. Finally, the addition of IFN-α reduced the HHV-8 load in PBMC. Thus, IFN-α appears to have inhibitory effects on HHV-8 persistent infection of PBMC. These results suggest that, in addition to inhibiting the expression of angiogenic factors that are key to KS development, IFN-α may induce KS regression by reducing the HHV-8 load and/or inhibiting virus reactivation. PMID:10196299

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

    Science.gov (United States)

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

    2009-05-01

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

  15. Anti IL-17A therapy inhibits bone loss in TNF-alpha-mediated murine arthritis by modulation of the T-cell balance.

    NARCIS (Netherlands)

    Zwerina, K.; Koenders, M.I.; Hueber, A.; Marijnissen, R.J.; Baum, W.; Heiland, G.R.; Zaiss, M.; McLnnes, I.; Joosten, L.A.B.; Berg, W.B. van den; Zwerina, J.; Schett, G.

    2012-01-01

    Tumour necrosis factor alpha (TNF-alpha) is a major inducer for inflammation and bone loss. Here, we investigated whether interleukin (IL)-17 plays a role in TNF-alpha-mediated inflammation and bone resorption. Human TNF-alpha transgenic (hTNFtg) mice were treated with a neutralizing anti-IL-17A ant

  16. Inhibition of TNF alpha during maturation of dendritic cells results in the development of semi-mature cells: a potential mechanism for the beneficial effects of TNF alpha blockade in rheumatoid arthritis.

    NARCIS (Netherlands)

    Lieshout, A.W.T. van; Barrera Rico, P.; Smeets, R.L.L.; Pesman, G.J.; Riel, P.L.C.M. van; Berg, W.B. van den; Radstake, T.R.D.J.

    2005-01-01

    BACKGROUND: Dendritic cells orchestrate pivotal immunological processes mediated by the production of cytokines and chemokines. OBJECTIVE: To assess whether neutralisation of tumour necrosis factor alpha (TNF alpha) during maturation of dendritic cells affects their phenotype and behaviour, which mi

  17. The role of prostaglandins in diabetes insipidus produced by desoxycorticosterone in the dog.

    Science.gov (United States)

    Düsing, R; Gill, J R; Güllner, H G; Bartter, F C

    1982-02-01

    To determine the role of renal prostaglandins (PGs) in the renal response to desoxycorticosterone acetate (DOCA), dogs were studied on a constant diet in which sodium intake was restricted (2.5 meq/day) or high (115 meq/day). On the restricted sodium intake, DOCA (25 mg/day im for 6 days) did not affect urinary volume, sodium, potassium, PGE2, or PGF2 alpha. On the high sodium intake, DOCA produced sodium retention for 1 day and a sustained increase in urinary potassium with a fall in serum potassium to 3.1 meq/liter. Urine volume increased from 574 +/- 50 to 1726 +/- 177 ml/day (P less than 0.001) with a fall in urinary osmolality from 1545 +/- 122 to 495 +/- 55 mosmol/ liter (P less than 0.001) as serum sodium increased from 149.0 +/- 1.0 to 152.5 +/- 0.3 meq/liter (P less than 0.025) by the sixth day of DOCA. Urinary PGE2 and PGF2 alpha were unchanged during the first 2 days of DOCA, then increased progressively from control values of 261 +/- 60 and 1143 +/- 144 ng/day ng/day, respectively, to 730 +/- 62 (P less than 0.005) and 3013 +/- 479 ng/day (P less than 0.01), respectively. Potassium repletion during continued DOCA treatment restored urinary volume, osmolality, PGE2 and PGF2 alpha, and serum sodium to control values. Treatment with indomethacin during DOCA-induced hypokalemia, polyuria, hypernatremia, and increased urinary PG, restored urinary PGs to control values, and corrected the polyuria and hypernatremia without a change in serum potassium. Thus, DOCA produced potassium depletion, polyuria, increased urinary PGs, and hypernatremia in dogs on a high sodium intake but not in those on a restricted sodium intake. As polyuria and hypernatremia were corrected either by potassium repletion, which corrected the supranormal renal synthesis of PGs, or by indomethacin, which inhibited their synthesis, renal water loss was presumably the result of an increase in renal PG synthesis, probably stimulated by potassium depletion.

  18. Role of renal prostaglandins in the modulation of cisplatinum nephrotoxicity

    Energy Technology Data Exchange (ETDEWEB)

    Noordewier, B.; Danielson, P.W.; Noordewier, E.R.; Bredehoeft, S.J.

    1986-03-01

    Indomethacin (I) inhibition of renal prostaglandin (PG) synthesis potentiates the nephorotoxic effects of cis-dichlorodiamine platinum (Cis-Pt). The purpose of this study was to determine if this potentiation was unique to I or was shared by other inhibitors of PG synthesis. Male Fischer 344 rats were fed a purified diet replete (Repl) or deplete (Depl) in sodium. After 5 days on this diet, the rats were given saline or cis-Pt (10 mg/kg, iv) with or without tolmetin (Tol) (2 x 10 mg/kg, ip then iv). Toxicity was assessed 2 days after the injections. Cis-Pt given alone increased BUN and plasma creatinine (Cr) in both Depl (BUN = 43 mg/dl, Cr = 1.3 mg/dl) and Repl (BUN = 45, Cr = 1.3) groups. Tol produced a moderate increase in cis-Pt toxicity in Repl rats (BUN = 62, Cr = 1.5) and a marked increase in Depl rats (BUN = 138, Cr = 2.6). These biochemical changes were accompanied by concurrent changes in renal histology. Rats given cis-Pt alone had focal areas of toxicity marked by evidence of necrosis and vacuolation. Tol enhancement of toxicity was characterized by an increased extent of damage with the appearance of tubular protein and some mineralization. The effects of Tol mimic those of I indicating a role for renal prostaglandins in the renal toxicity of Cis-Pt.

  19. Expression of the prostaglandin F synthase AKR1B1 and the prostaglandin transporter SLCO2A1 in human fetal membranes in relation to spontaneous term and preterm labour

    Directory of Open Access Journals (Sweden)

    Hana A Alzamil

    2014-07-01

    Full Text Available Background: Human labour is a complex series of cellular and molecular events that occur at the materno-fetal and uterine levels. Many hypotheses have been proposed for the initiation of human labour, one hypothesis suggests that maturation of the fetus releases a signal in the amniotic fluid that will be transmitted to myometrium via the fetal membranes and initiate uterine contractions. There is strong evidence that prostaglandins (PGs play a central role in initiation and progression of human labour. Objectives: In this study we intended to investigate the expression of prostaglandin F synthase and the prostaglandin transporter in the human fetal membranes and to explore the relationship between cytokines and PGs in the mechanism of human labour. Methods: We used fetal membranes obtained before labour at term and after spontaneous labour at term or preterm to identify the changes in prostaglandin F synthase (AKR1B1 and human prostaglandin transporter (SLCO2A1 proteins in relation to parturition. Using fetal membranes explants we tested the effect of cytokines (interleukin-1 and tumour necrosis factor alpha on PG production and the concomitant changes in cyclooxygenase-2 (PTGS2, AKR1B1 and SLCO2A1 expression. Results: Expression of PTGS2 and AKR1B1 was upregulated in the fetal membranes in association with term labour while SLCO2A1 was downregulated with advancing gestation and during term labour. Before labour, IL-1 increased the expression of PTGS2, however during labour TNF upregulated PTGS2 and AKR1B1 proteins. Conclusions: The prostaglandin F synthase AKR1B1 is upregulated while prostaglandin transporter is downregulated during term labour. The amnion is more responsive than choriodecidua to stimulation with pro-inflammatory cytokines. The mechanisms of term and preterm labour are different.

  20. Human sputum cathepsin B degrades proteoglycan, is inhibited by alpha 2-macroglobulin and is modulated by neutrophil elastase cleavage of cathepsin B precursor and cystatin C.

    Science.gov (United States)

    Buttle, D J; Abrahamson, M; Burnett, D; Mort, J S; Barrett, A J; Dando, P M; Hill, S L

    1991-01-01

    The high-Mr alkali-stable form of cathepsin B was purified from purulent human sputum. It was shown to solubilize proteoglycan monomer entrapped in polyacrylamide at a rate comparable with that of human lysosomal cathepsin B. Like the enzyme from lysosomes, sputum cathepsin B was bound by human alpha 2-macroglobulin, which inhibited its action on proteoglycan. Cystatin C in purulent sputum was shown to be the N-terminally truncated form generated by neutrophil elastase cleavage, and sputum cathepsin B was only weakly inhibited by recombinant cystatin C that had been cleaved by neutrophil elastase in vitro. Addition of neutrophil elastase to mucoid sputum led to a 5-fold increase in cathepsin B activity concomitant with a lowering in Mr of the cysteine proteinase from 40,000 to 37,000, i.e. the size of the active enzyme purified from purulent sputum. It is concluded that the high-Mr form of cathepsin B present in purulent sputum is a functional proteinase, unlike similar forms of the enzyme secreted by mammary gland in organ culture. The activity of cathepsin B in sputum is modulated by neutrophil elastase, by a combination of inhibitor inactivation and zymogen activation. Images Fig. 3. Fig. 4. Fig. 5. PMID:1710889

  1. Potentiation of excitatory transmission in substantia gelatinosa neurons of rat spinal cord by inhibition of estrogen receptor alpha

    Directory of Open Access Journals (Sweden)

    Li Kai-Cheng

    2010-12-01

    Full Text Available Abstract Background It has been shown that estrogen is synthesized in the spinal dorsal horn and plays a role in modulating pain transmission. One of the estrogen receptor (ER subtypes, estrogen receptor alpha (ERα, is expressed in the spinal laminae I-V, including substantia gelatinosa (SG, lamina II. However, it is unclear how ERs are involved in the modulation of nociceptive transmission. Results In the present study, a selective ERα antagonist, methyl-piperidino-pyrazole (MPP, was used to test the potential functional roles of spinal ERα in the nociceptive transmission. Using the whole-cell patch-clamp technique, we examined the effects of MPP on SG neurons in the dorsal root-attached spinal cord slice prepared from adult rats. We found that MPP increased glutamatergic excitatory postsynaptic currents (EPSCs evoked by the stimulation of either Aδ- or C-afferent fibers. Further studies showed that MPP treatment dose-dependently increased spontaneous EPSCs frequency in SG neurons, while not affecting the amplitude. In addition, the PKC was involved in the MPP-induced enhancement of synaptic transmission. Conclusions These results suggest that the selective ERα antagonist MPP pre-synaptically facilitates the excitatory synaptic transmission to SG neurons. The nociceptive transmission evoked by Aδ- and C-fiber stimulation could be potentiated by blocking ERα in the spinal neurons. Thus, the spinal estrogen may negatively regulate the nociceptive transmission through the activation of ERα.

  2. Soluble amyloid precursor protein alpha (sAPPα) inhibits tau phosphorylation through modulation of GSK3β signaling pathway

    Science.gov (United States)

    Deng, Juan; Habib, Ahsan; Obregon, Demian F.; Barger, Steven W.; Giunta, Brian; Wang, Yan-Jiang; Hou, Huayan; Sawmiller, Darrell; Tan, Jun

    2015-01-01

    We recently found that sAPPα decreases Aβ generation by directly associating with β-site amyloid precursor protein (APP) converting enzyme 1 (BACE1), thereby modulating APP processing. Because inhibition of BACE1 decreases GSK3β-mediated Alzheimer’s disease (AD)-like tau phosphorylation in AD patient-derived neurons, we determined whether sAPPα also reduces GSK3β-mediated tau phosphorylation. We initially found increased levels of inhibitory phosphorylation of GSK3β in primary neurons from sAPPα over-expressing mice. Further, recombinant human sAPPα evoked the same phenomenon in SH-SY5Y cells. Further, in SH-SY5Y cells overexpressing BACE1, and HeLa cells overexpressing human tau, sAPPα reduced GSK3β activity and tau phosphorylation. Importantly, the reductions in GSK3β activity and tau phosphorylation elicited by sAPPα were prevented by BACE1 but not γ-secretase inhibition. In accord, AD mice overexpressing human sAPPα had less GSK3β activity and tau phosphorylation compared with controls. These results implicate a direct relationship between APP β-processing and GSK3β-mediated tau phosphorylation and further define the central role of sAPPα in APP autoregulation and AD pathogenesis. PMID:26342176

  3. The relationship between factor inhibiting HIF-1-alpha (HIF1AN( expression and vascular invasion in colon cancer

    Directory of Open Access Journals (Sweden)

    Reza Najafipour

    2016-10-01

    Full Text Available Background: Hypoxia is a common phenomenon in human solid tumors which by increasing in angiogenesis induction cause tumor growth survival and metastasis. Inhibitory factor hypoxia regulatory factor (HIF1AN by binding to transcription co activators CBP/P300(, inhibits hypoxia inducible factor (HIF1α. Objective: The relationship between HIF1AN expression and vascular invasion in colon tumors. Methods: The study included 101 patients with colon adenocarcinoma which were divided to vascular invasion and non-vascular invasion groups. Tumor paraffin blocks were immunohistochemistry stained for HIF1AN and were assessed for intensity and extent of positivity. Statistical relation of marker expression and clinic pathologic findings were assessed. Data were analyzed by SPSS 21 software and logistic regression and chi-square test. Findings: Nuclear immunoreactivity of HIF1AN was different between two groups. Statistical relation between low HIF1AN expression and tumor vascular invasion were seen (P=0.01. No relation was found between tumor differentiation, depth and HIF1AN. Conclusion: Evidence showed that the low expression or incorrect position of HIF1AN in nucleus of tumor cells was effective on HIF1α inhibition failure and factors associated angiogenesis increased. The HIF1AN played an tumor suppressor gene (TSG( role in colon tumors and decreased protein in the nucleus of colon cancer cells increased the expression of angiogenesis factors and vascular invasion.

  4. Suppressive effects of antimycotics on tumor necrosis factor-alpha-induced CCL27, CCL2, and CCL5 production in human keratinocytes.

    Science.gov (United States)

    Kanda, Naoko; Watanabe, Shinichi

    2006-08-14

    Antimycotic agents are reported to improve cutaneous symptoms of atopic dermatitis or psoriasis vulgaris. Keratinocytes in these lesions excessively produce chemokines, CCL27, CCL2, or CCL5 which trigger inflammatory infiltrates. Tumor necrosis factor-alpha (TNF-alpha) induces production of these chemokines via activating nuclear factor-kappaB (NF-kappaB). We examined in vitro effects of antimycotics on TNF-alpha-induced CCL27, CCL2, and CCL5 production in human keratinocytes. Antimycotics ketoconazole and terbinafine hydrochloride suppressed TNF-alpha-induced CCL27, CCL2, and CCL5 secretion and mRNA expression in keratinocytes in parallel to the inhibition of NF-kappaB activity while fluconazole was ineffective. Anti-prostaglandin E2 (PGE2) antiserum or antisense oligonucleotides against PGE2 receptor EP2 or EP3 abrogated inhibitory effects of ketoconazole and terbinafine hydrochloride on TNF-alpha-induced NF-kappaB activity and CCL27, CCL2, and CCL5 production, indicating the involvement of endogenous PGE2 in the inhibitory effects. Prostaglandin H2, a precursor of PGE2 can be converted to thromboxane A2. Ketoconazole, terbinafine hydrochloride and thromboxane A2 synthase (EC 5.3.99.5) inhibitor, carboxyheptyl imidazole increased PGE2 release from keratinocytes and reduced that of thromboxane B2, a stable metabolite of thromboxane A2. Carboxyheptyl imidazole also suppressed TNF-alpha-induced NF-kappaB activity and CCL27, CCL2, and CCL5 production. These results suggest that ketoconazole and terbinafine hydrochloride may suppress TNF-alpha-induced NF-kappaB activity and CCL27, CCL2, and CCL5 production by increasing PGE2 release from keratinocytes. These antimycotics may suppress thromboxane A2 synthesis and redirect the conversion of PGH2 toward PGE2. These antimycotics may alleviate inflammatory infiltration in atopic dermatitis or psoriasis vulgaris by suppressing chemokine production.

  5. Characterizing alpha helical properties of Ebola viral proteins as potential targets for inhibition of alpha-helix mediated protein-protein interactions [v3; ref status: indexed, http://f1000r.es/50u

    Directory of Open Access Journals (Sweden)

    Sandeep Chakraborty

    2015-01-01

    Full Text Available Ebola, considered till recently as a rare and endemic disease, has dramatically transformed into a potentially global humanitarian crisis. The genome of Ebola, a member of the Filoviridae family, encodes seven proteins. Based on the recently implemented software (PAGAL for analyzing the hydrophobicity and amphipathicity properties of alpha helices (AH in proteins, we characterize the helices in the Ebola proteome. We demonstrate that AHs with characteristically unique features are involved in critical interactions with the host proteins. For example, the Ebola virus membrane fusion subunit, GP2, from the envelope glycoprotein ectodomain has an AH with a large hydrophobic moment. The neutralizing antibody (KZ52 derived from a human survivor of the 1995 Kikwit outbreak recognizes a protein epitope on this AH, emphasizing the critical nature of this secondary structure in the virulence of the Ebola virus. Our method ensures a comprehensive list of such `hotspots'. These helices probably are or can be the target of molecules designed to inhibit AH mediated protein-protein interactions. Further, by comparing the AHs in proteins of the related Marburg viruses, we are able to elicit subtle changes in the proteins that might render them ineffective to previously successful drugs. Such differences are difficult to identify by a simple sequence or structural alignment. Thus, analyzing AHs in the small Ebola proteome can aid rational design aimed at countering the `largest Ebola epidemic, affecting multiple countries in West Africa' (http://www.cdc.gov/vhf/ebola/outbreaks/2014-west-africa/index.html.

  6. Functional interaction of hepatic nuclear factor-4 and peroxisome proliferator-activated receptor-gamma coactivator 1alpha in CYP7A1 regulation is inhibited by a key lipogenic activator, sterol regulatory element-binding protein-1c.

    Science.gov (United States)

    Ponugoti, Bhaskar; Fang, Sungsoon; Kemper, Jongsook Kim

    2007-11-01

    Insulin inhibits transcription of cholesterol 7alpha-hydroxylase (Cyp7a1), a key gene in bile acid synthesis, and the hepatic nuclear factor-4 (HNF-4) site in the promoter was identified as a negative insulin response sequence. Using a fasting/feeding protocol in mice and insulin treatment in HepG2 cells, we explored the inhibition mechanisms. Expression of sterol regulatory element-binding protein-1c (SREBP-1c), an insulin-induced lipogenic factor, inversely correlated with Cyp7a1 expression in mouse liver. Interaction of HNF-4 with its coactivator, peroxisome proliferator-activated receptor-gamma coactivator 1alpha (PGC-1alpha), was observed in livers of fasted mice and was reduced after feeding. Conversely, HNF-4 interaction with SREBP-1c was increased after feeding. In vitro studies suggested that SREBP-1c competed with PGC-1alpha for direct interaction with the AF2 domain of HNF-4. Reporter assays showed that SREBP-1c, but not of a SREBP-1c mutant lacking the HNF-4 interacting domain, inhibited HNF-4/PGC-1alpha transactivation of Cyp7a1. SREBP-1c also inhibited PGC-1alpha-coactivation of estrogen receptor, constitutive androstane receptor, pregnane X receptor, and farnesoid X receptor, implying inhibition of HNF-4 by SREBP-1c could extend to other nuclear receptors. In chromatin immunoprecipitation studies, HNF-4 binding to the promoter was not altered, but PGC-1alpha was dissociated, SREBP-1c and histone deacetylase-2 (HDAC2) were recruited, and acetylation of histone H3 was decreased upon feeding. Adenovirus-mediated expression of a SREBP-1c dominant-negative mutant, which blocks the interaction of SREBP-1c and HNF-4, partially but significantly reversed the inhibition of Cyp7a1 after feeding. Our data show that SREBP-1c functions as a non-DNA-binding inhibitor and mediates, in part, suppression of Cyp7a1 by blocking functional interaction of HNF-4 and PGC-1alpha. This mechanism may be relevant to known repression of many other HNF-4 target genes upon

  7. Depletion of OLFM4 gene inhibits cell growth and increases sensitization to hydrogen peroxide and tumor necrosis factor-alpha induced-apoptosis in gastric cancer cells

    Directory of Open Access Journals (Sweden)

    Liu Rui-hua

    2012-04-01

    Full Text Available Abstract Background Human olfactomedin 4 (OLFM4 gene is a secreted glycoprotein more commonly known as the anti-apoptotic molecule GW112. OLFM4 is found to be frequently up-regulated in many types of human tumors including gastric cancer and it was believed to play significant role in the progression of gastric cancer. Although the function of OLFM4 has been indicated in many studies, recent evidence strongly suggests a cell or tissue type-dependent role of OLFM4 in cell growth and apoptosis. The aim of this study is to examine the role of gastric cancer-specific expression of OLFM4 in cell growth and apoptosis resistance. Methods OLFM4 expression was eliminated by RNA interference in SGC-7901 and MKN45 cells. Cell proliferation, anchorage-independent growth, cell cycle and apoptosis were characterized in vitro. Tumorigenicity was analyzed in vivo. The apoptosis and caspase-3 activation in response to hydrogen peroxide (H2O2 or tumor necrosis factor-alpha (TNF α were assessed in the presence or absence of caspase inhibitor Z-VAD-fmk. Results The elimination of OLFM4 protein by RNA interference in SGC-7901 and MKN45 cells significantly inhibits tumorigenicity both in vitro and in vivo by induction of cell G1 arrest (all P 2O2 or TNF α-induced apoptosis and caspase-3 activity (all P 2O2 or TNF α-induced apoptosis in OLFM4 knockdown cells (all P Conclusion Our study suggests that depletion of OLFM4 significantly inhibits tumorigenicity of the gastric cancer SGC-7901 and MKN45 cells. Blocking OLFM4 expression can sensitize gastric cancer cells to H2O2 or TNF α treatment by increasing caspase-3 dependent apoptosis. A combination strategy based on OLFM4 inhibition and anticancer drugs treatment may provide therapeutic potential in gastric cancer intervention.

  8. In vitro inhibition of enterobacteria-reactive CD4+Tumor necrosis factor-alpha binding capacity and anti-infliximab antibodies measured by fluid-phase radioimmunoassays as predictors of clinical efficacy of infliximab in Crohn's disease

    DEFF Research Database (Denmark)

    Mangano, K.; Sardesai, N.; D'Alcamo, M.;

    2008-01-01

    VGX-1027 is an isozaxoline compound that has recently been found to primarily target the function of murine macrophages but not of T cells, inhibiting secretion of tumor necrosis factor (TNF)-alpha in response to different Toll-like receptor agonists in vitro and in vivo. The well-defined role...

  9. N-Acetylcysteine enhances the action of anti-inflammatory drugs as suppressors of prostaglandin production in monocytes

    Directory of Open Access Journals (Sweden)

    Erica Hoffer

    2002-01-01

    Full Text Available The anti-inflammatory effect of non-steroidal anti-inflammatory drugs (NSAIDs is associated with inhibition of cyclooxygenase (COX, the rate-limiting enzyme responsible for the synthesis of prostaglandins. Since oxygen free radicals can act as second cellular messengers, especially to modulate the metabolism of arachidonic acid and the prostaglandin tract, it seems plausible that antioxidants might affect the production of prostaglandin by activated cells. This research is focused on the effect of the antioxidant N-acetylcysteine (NAC on the inhibition of prostaglandin E2 formation in activated monocytes by specific and non-specific COX inhibitors. We found that lipopolysaccharide-induced prostaglandin E2 formation was significantly reduced by rofecoxib and by diclofenac, two NSAIDs. Addition of NAC to each of these drugs enhanced the effect of the NSAIDs. These results suggest that one might expect either a potentiation of the anti-inflammatory effect of COX inhibitors by their simultaneous administration with NAC, or obtaining the same anti-inflammatory at lower drug levels.

  10. Effect of estrus induction on prostaglandin content and prostaglandin synthesis enzyme expression in the uterus of early pregnant pigs.

    Science.gov (United States)

    Blitek, A; Waclawik, A; Kaczmarek, M M; Kiewisz, J; Ziecik, A J

    2010-06-01

    Prostaglandins (PGs) play a pivotal role in maternal recognition of pregnancy and implantation in pigs. In the present study, PGE(2), PGF(2alpha), and PGFM (PGF(2alpha) metabolite) content, as well as PGE(2) synthase (mPGES-1) and PGF(2alpha) synthase (PGFS) expression was investigated in early pregnant gilts with natural (n=21) and PMSG/hCG-stimulated (n=19) estrus. Endometrial tissue samples, uterine luminal flushings (ULFs), and blood serum were collected on days 10-11, 12, and 15 after insemination. Additionally, day 15 conceptuses were collected for mPGES-1 and PGFS protein expression. Effect of estrus induction was observed on day 15 of pregnancy, when the content of PGE(2) in the uterine lumen was fourfold lower in gonadotropin-stimulated gilts in comparison to controls (P<0.001). Decreased PGE(2) content in ULFs of gonadotropin-treated pigs was preceded by lower endometrial mPGES-1 gene expression in hormonally-stimulated animals in comparison to control gilts (P<0.01). On the other hand, estrus induction with PMSG/hCG resulted in higher PGE(2) accumulation in the endometrial tissue on day 15 of pregnancy (P<0.01). Furthermore, PGF(2alpha) content in the endometrium and PGFM levels in blood serum were lower in gonadotropin-treated gilts, especially on day 12 after insemination when compared to control gilts (P<0.01). Finally, PGFS expression in day 15 conceptuses was decreased in animals with hormonally-induced estrus. We conclude that PMSG/hCG stimulation of prepubertal gilts to induce estrus results in changes of PG production and secretion during early pregnancy, which, in turn, may affect conceptus development, implantation, and the course of pregnancy.

  11. Genomic amplification upregulates estrogen-related receptor alpha and its depletion inhibits oral squamous cell carcinoma tumors in vivo.

    Science.gov (United States)

    Tiwari, Ankana; Swamy, Shivananda; Gopinath, Kodaganur S; Kumar, Arun

    2015-12-07

    The ESRRA gene encodes a transcription factor and regulates several genes, such as WNT11 and OPN, involved in tumorigenesis. It is upregulated in several cancers, including OSCC. We have previously shown that the tumor suppressor miR-125a targets ESRRA, and its downregulation causes upregulation of ESRRA in OSCC. Upregulation of ESRRA in the absence of downregulation of miR-125a in a subset of OSCC samples suggests the involvement of an alternative mechanism. Using TaqMan(®) copy number assay, here we report for the first time that the genomic amplification of ESRRA causes its upregulation in a subset of OSCC samples. Ectopic overexpression of ESRRA led to accelerated cell proliferation, anchorage-independent cell growth and invasion, and inhibited apoptosis. Whereas, knockdown of ESRRA expression by siRNA led to reduced cell proliferation, anchorage-independent cell growth and invasion, and accelerated apoptosis. Furthermore, the delivery of a synthetic biostable ESRRA siRNA to OSCC cells resulted in regression of xenografts in nude mice. Thus, the genomic amplification of ESRRA is another novel mechanism for its upregulation in OSCC. Based on our in vitro and in vivo experiments, we suggest that targeting ESRRA by siRNA could be a novel therapeutic strategy for OSCC and other cancers.

  12. Prostaglandin E2 As a Modulator of Viral Infections

    Science.gov (United States)

    Sander, Willem J.; O'Neill, Hester G.; Pohl, Carolina H.

    2017-01-01

    Viral infections are a major cause of infectious diseases worldwide. Inflammation and the immune system are the major host defenses against these viral infection. Prostaglandin E2 (PGE2), an eicosanoid generated by cyclooxygenases, has been shown to modulate inflammation and the immune system by regulating the expression/concentration of cytokines. The effect of PGE2 on viral infection and replication is cell type- and virus-family-dependent. The host immune system can be modulated by PGE2, with regards to immunosuppression, inhibition of nitrogen oxide (NO) production, inhibition of interferon (IFN) and apoptotic pathways, and inhibition of viral receptor expression. Furthermore, PGE2 can play a role in viral infection directly by increasing the production and release of virions, inhibiting viral binding and replication, and/or stimulating viral gene expression. PGE2 may also have a regulatory role in the induction of autoimmunity and in signaling via Toll-like receptors. In this review the known effects of PGE2 on the pathogenesis of various infections caused by herpes simplex virus, rotavirus, influenza A virus and human immunodeficiency virus as well the therapeutic potential of PGE2 are discussed. PMID:28261111

  13. A Single-Domain Llama Antibody Potently Inhibits the Enzymatic Activity of Botulinum Neurotoxin by Binding to the Non-Catalytic [alpha]-Exosite Binding Region

    Energy Technology Data Exchange (ETDEWEB)

    Dong, Jianbo; Thompson, Aaron A.; Fan, Yongfeng; Lou, Jianlong; Conrad, Fraser; Ho, Mengfei; Pires-Alves, Melissa; Wilson, Brenda A.; Stevens, Raymond C.; Marks, James D. (UIUC); (Scripps); (UCSF)

    2010-08-13

    Ingestion or inhalation of botulinum neurotoxin (BoNT) results in botulism, a severe and frequently fatal disease. Current treatments rely on antitoxins, which, while effective, cannot reverse symptoms once BoNT has entered the neuron. For treatments that can reverse intoxication, interest has focused on developing inhibitors of the enzymatic BoNT light chain (BoNT Lc). Such inhibitors typically mimic substrate and bind in or around the substrate cleavage pocket. To explore the full range of binding sites for serotype A light chain (BoNT/A Lc) inhibitors, we created a library of non-immune llama single-domain VHH (camelid heavy-chain variable region derived from heavy-chain-only antibody) antibodies displayed on the surface of the yeast Saccharomyces cerevisiae. Library selection on BoNT/A Lc yielded 15 yeast-displayed VHH with equilibrium dissociation constants (K{sub d}) from 230 to 0.03 nM measured by flow cytometry. Eight of 15 VHH inhibited the cleavage of substrate SNAP25 (synaptosome-associated protein of 25,000 Da) by BoNT/A Lc. The most potent VHH (Aa1) had a solution K{sub d} for BoNT/A Lc of 1.47 x 10{sup -10} M and an IC{sub 50} (50% inhibitory concentration) of 4.7 x 10{sup -10} M and was resistant to heat denaturation and reducing conditions. To understand the mechanism by which Aa1 inhibited catalysis, we solved the X-ray crystal structure of the BoNT/A Lc-Aa1 VHH complex at 2.6 {angstrom} resolution. The structure reveals that the Aa1 VHH binds in the {alpha}-exosite of the BoNT/A Lc, far from the active site for catalysis. The study validates the utility of non-immune llama VHH libraries as a source of enzyme inhibitors and identifies the BoNT/A Lc {alpha}-exosite as a target for inhibitor development.

  14. Study of RNA interference inhibiting rat ovarian androgen biosynthesis by depressing 17alpha-hydroxylase/17, 20-lyase activity in vivo

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    Yang Xing

    2009-07-01

    Full Text Available Abstract Background 17alpha-hydroxylase/17, 20-lyase encoded by CYP17 is the key enzyme in androgen biosynthesis pathway. Previous studies demonstrated the accentuation of the enzyme in patients with polycystic ovary syndrome (PCOS was the most important mechanism of androgen excess. We chose CYP17 as the therapeutic target, trying to suppress the activity of 17alpha-hydroxylase/17, 20-lyase and inhibit androgen biosynthesis by silencing the expression of CYP17 in the rat ovary. Methods Three CYP17-targeting and one negative control oligonucleotides were designed and used in the present study. The silence efficiency of lentivirus shRNA was assessed by qRT-PCR, Western blotting and hormone assay. After subcapsular injection of lentivirus shRNA in rat ovary, the delivery efficiency was evaluated by GFP fluorescence and qPCR. Total RNA was extracted from rat ovary for CYP17 mRNA determination and rat serum was collected for hormone measurement. Results In total, three CYP17-targeting lentivirus shRNAs were synthesized. The results showed that all of them had a silencing effect on CYP17 mRNA and protein. Moreover, androstenedione secreted by rat theca interstitial cells (TIC in the RNAi group declined significantly compared with that in the control group. Two weeks after rat ovarian subcapsular injection of chosen CYP17 shRNA, the GFP fluorescence of frozen ovarian sections could be seen clearly under fluorescence microscope. It also showed that the GFP DNA level increased significantly, and its relative expression level was 7.42 times higher than that in the control group. Simultaneously, shRNA treatment significantly decreased CYP17 mRNA and protein levels at 61% and 54%, respectively. Hormone assay showed that all the levels of androstenedione, 17-hydroxyprogesterone and testosterone declined to a certain degree, but progesterone levels declined significantly. Conclusion The present study proves for the first time that ovarian androgen

  15. Migraine: possible role of platelet insensitivity to prostaglandin E1 (PGE1).

    Science.gov (United States)

    Cerneca, F; de Luyk, S; Radillo, O; Simeone, R; Mangiarotti, M

    1993-01-01

    Platelet aggregation inhibition, induced by prostaglandin E1 (PGE1), was evaluated in 38 patients affected by migraine. Our data indicate a complete insensitivity to PGE1 in these subjects. The insensitivity to PGE1 leads to decreased cyclic-AMP (cAMP) levels, determining an imbalance in the inhibitory mechanism. From this observation we can suppose that the decreased affinity of PGE1-receptors, causing decreased cAMP levels, may be involved in pathogenesis of migraine.

  16. Moxibustion inhibits interleukin-12 and tumor necrosis factor alpha and modulates intestinal flora in rat with ulcerative colitis

    Institute of Scientific and Technical Information of China (English)

    Xiao-Mei Wang; Yuan Lu; Lu-Yi Wu; Shu-Guang Yu; Bai-Xiao Zhao; Hong-Yi Hu; Huan-Gan Wu

    2012-01-01

    AIM:To investigate the effect of moxibustion on intestinal flora and release of interleukin-12 (IL-12) and tumor necrosis factor-α (TNF-α) from the colon in rat with ulcerative colitis (UC).METHODS:A rat model of UC was established by local stimulation of the intestine with supernatant from colonic contents harvested from human UC patients.A total of 40 male Sprague-Dawley rats were randomly divided into the following groups:normal (sham),model (UC),herb-partition moxibustion (HPM-treated),and positive control sulfasalazine (SA-treated).Rats treated with HPM received HPM at acupuncture points ST25 and RN6,once a day for 15 min,for a total of 8 d.Rats in the SA group were perfused with SA twice a day for 8 d.The colonic histopathology was observed by hematoxylin-eosin.The levels of intestinal flora,including Bifidobacterium,Lactobacillus,Escherichia coli (E.coli),and Bacteroides fragilis (B.fragilis),were tested by real-time quantitative polymerase chain reaction to detect bacterial 16S rRNA/DNA in order to determine DNA copy numbers of each specific species.Immunohistochemical assays were used to observe the expression of TNF-α and IL-12 in the rat colons.RESULTS:HPM treatment inhibited immunopathology in colonic tissues of UC rats; the general morphological score and the immunopathological score were significantly decreased in the HPM and SA groups compared with the model group [3.5 (2.0-4.0),3.0 (1.5-3.5) vs 6.0 (5.5-7.0),P < 0.05 for the general morphological score,and 3.00 (2.00-3.50),3.00 (2.50-3.50) vs 5.00 (4.50-5.50),P < 0.01 for the immunopathological score].As measured by DNA copy number,we found that Bilidobacterium and Lactobacillus,which are associated with a healthy colon,were significantly higher in the HPM and SA groups than in the model group (1.395± 1.339,1.461 ± 1.152 vs 0.045 ± 0.036,P < 0.01 for Bifidobacterium,and 0.395 ± 0.325,0.851 ± 0.651 vs 0.0015 ± 0.0014,P < 0.01 for Lactobacillus).On the other hand,E.coli and B

  17. EWS-FLI1 inhibits TNF{alpha}-induced NF{kappa}B-dependent transcription in Ewing sarcoma cells

    Energy Technology Data Exchange (ETDEWEB)

    Lagirand-Cantaloube, Julie, E-mail: julie.cantaloube@crbm.cnrs.fr [UMR8113 CNRS, LBPA, Ecole Normale Superieure, Cachan (France); Laud, Karine, E-mail: karine.laud@curie.fr [U830 INSERM, Institut Curie, Paris (France); Institut Curie, Genetique et biologie des cancers, Paris (France); Lilienbaum, Alain, E-mail: alain.lilienbaum@univ-paris-diderot.fr [EA300 Universite Paris 7, Stress et pathologies du cytosquelette, Paris (France); Tirode, Franck, E-mail: franck.tirode@curie.fr [U830 INSERM, Institut Curie, Paris (France); Institut Curie, Genetique et biologie des cancers, Paris (France); Delattre, Olivier, E-mail: olivier.delattre@curie.fr [U830 INSERM, Institut Curie, Paris (France); Institut Curie, Genetique et biologie des cancers, Paris (France); Auclair, Christian, E-mail: auclair@lbpa.ens-cachan.fr [UMR8113 CNRS, LBPA, Ecole Normale Superieure, Cachan (France); Kryszke, Marie-Helene, E-mail: kryszke@lbpa.ens-cachan.fr [UMR8113 CNRS, LBPA, Ecole Normale Superieure, Cachan (France)

    2010-09-03

    Research highlights: {yields} EWS-FLI1 interferes with TNF-induced activation of NF{kappa}B in Ewing sarcoma cells. {yields} EWS-FLI1 knockdown in Ewing sarcoma cells increases TNF-induced NF{kappa}B binding to DNA. {yields} EWS-FLI1 reduces TNF-stimulated NF{kappa}B-dependent transcriptional activation. {yields} Constitutive NF{kappa}B activity is not affected by EWS-FLI1. {yields} EWS-FLI1 physically interacts with NF{kappa}B p65 in vivo. -- Abstract: Ewing sarcoma is primarily caused by a t(11;22) chromosomal translocation encoding the EWS-FLI1 fusion protein. To exert its oncogenic function, EWS-FLI1 acts as an aberrant transcription factor, broadly altering the gene expression profile of tumor cells. Nuclear factor-kappaB (NF{kappa}B) is a tightly regulated transcription factor controlling cell survival, proliferation and differentiation, as well as tumorigenesis. NF{kappa}B activity is very low in unstimulated Ewing sarcoma cells, but can be induced in response to tumor necrosis factor (TNF). We wondered whether NF{kappa}B activity could be modulated by EWS-FLI1 in Ewing sarcoma. Using a knockdown approach in Ewing sarcoma cells, we demonstrated that EWS-FLI1 has no influence on NF{kappa}B basal activity, but impairs TNF-induced NF{kappa}B-driven transcription, at least in part through inhibition of NF{kappa}B binding to DNA. We detected an in vivo physical interaction between the fusion protein and NF{kappa}B p65, which could mediate these effects. Our findings suggest that, besides directly controlling the activity of its primary target promoters, EWS-FLI1 can also indirectly influence gene expression in tumor cells by modulating the activity of key transcription factors such as NF{kappa}B.

  18. Inhibition of tumor necrosis factor-alpha by sodium ferulate in protecting neurons from beta-amyloid induced damage

    Institute of Scientific and Technical Information of China (English)

    Suyan Yao; Deyu Zheng; Zhuo Liu; Ying Jin

    2006-01-01

    BACKGROUND: Sodium ferulate (SF) has an effect of anti-inflammation; however, whether it can inhibit beta-amyloid (Aβ) induced damage or not should be further studied.OBJECTIVE: To investigate the effects of SF on neurotoxicity mediated by Aβ-induced macrophage activation via inhibiting tumor necrosis factor-α (TNF-α) in vitro.DESTGN: A contrast experiment based on cells.SETTrNG: Departments of Pathophysiology, Pharmacology and Anatomy, Liaoning Medical College.MATERTALS: A total of 36 Kunming mice aged 8-10 weeks and some SD rats aged 2-3 days of both genders were selected in this study. Main reagents were detailed as follows: Aβ peptide (Sigma Company); SF (purity >99%, Suzhou Changtong Chemical Co., Ltd.); lactate dehydrogenase (LDH) assay kit (Bangding Biological Engineering Co., Beijing, China); microtubule-associated protein 2 (MAP-2) monoclonal antibodies and TNF-αmonoclonal antibodies (Boster Biological Engineering Co., Wuhan, China).METHODS: The experiment was carried out in Laboratories of Pharmacology and Anatomy, Liaoning Medical College from May to December 2004. Cerebellum was obtained from rats under sterile condition to culture neurons and macrophages taken from mice abdominal cavity. Later, two parallel experiments were performed as follows: ① Macrophages culture groups: In normal control group, macrophages were cultured in DMEM after being seeded. In Aβ group, neurotoxic form of Aβ was added into DMEM media with final concentration of 10 μmol/L after macrophages were seeded for 24 hours. In Aβ+SF group, ten minutes after Aβ treatment, for 10, 100, 500 μmol/L and 1 mmol/L of SF were added to the media of the macrophages culture. ②Macrophages-neurons co-cultured groups: Control macrophages-neurons were co-cultured. Aβ group:Neurotoxic form of Aβ was added into the media with concentration of 10 iμmol/L after macrophages were seeded in the neurons cultured wells for 24 hours. Aβ±SF group: Ten minutes after Aβ treatment, 10

  19. A novel peptide (GX1 homing to gastric cancer vasculature inhibits angiogenesis and cooperates with TNF alpha in anti-tumor therapy

    Directory of Open Access Journals (Sweden)

    Wang Li

    2009-09-01

    Full Text Available Abstract Background The discovery of the importance of angiogenesis in tumor growth has emphasized the need to find specific vascular targets for tumor-targeted therapies. Previously, using phage display technology, we identified the peptide GX1 as having the ability to target the gastric cancer vasculature. The present study investigated the bioactivities of GX1, as well as its potential ability to cooperate with recombinant mutant human tumor necrosis factor alpha (rmhTNFα, in gastric cancer therapy. Results Tetrazolium salt (MTT assay showed that GX1 could inhibit cell proliferation of both human umbilical vein endothelial cells (HUVEC (44% and HUVEC with tumor endothelium characteristics, generated by culturing in tumor-conditioned medium (co-HUVEC (62%. Flow-cytometry (FCM and western blot assays showed that GX1 increased the rate of apoptosis from 11% to 31% (p in vivo, with the microvessel count decreasing from 21 to 11 (p In vitro MTT and FCM assays showed that, compared to rmhTNFα alone, GX1-rmhTNFα was more effective at suppressing co-HUVEC proliferation (45% vs. 61%, p p 3 vs. 134 mm3, p p Conclusion GX1 had both homing activity and the ability to inhibit vascular endothelial cell proliferation in vitro and neovascularization in vivo. Furthermore, when GX1 was conjugated to rmhTNFα, the fusion protein was selectively delivered to targeted tumor sites, significantly improving the anti-tumor activity of rmhTNFα and decreasing systemic toxicity. These results demonstrate the potential of GX1 as a homing peptide in vascular targeted therapy for gastric cancer.

  20. Berberine and a Berberis lycium extract inactivate Cdc25A and induce {alpha}-tubulin acetylation that correlate with HL-60 cell cycle inhibition and apoptosis

    Energy Technology Data Exchange (ETDEWEB)

    Khan, Musa [Department of Plant Sciences, Quaid-i-Azam University Islamabad (Pakistan); Institute of Clinical Pathology, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria); Department of Pharmacognosy, Faculty of Life Sciences, University of Vienna, Althanstrasse 14 (Austria); Giessrigl, Benedikt; Vonach, Caroline; Madlener, Sibylle [Institute of Clinical Pathology, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria); Prinz, Sonja [Department of Pharmacognosy, Faculty of Life Sciences, University of Vienna, Althanstrasse 14 (Austria); Herbaceck, Irene; Hoelzl, Christine [Department of Medicine I, Institute of Cancer Research, Medical University of Vienna, Borschkegasse 8a (Austria); Bauer, Sabine; Viola, Katharina [Institute of Clinical Pathology, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria); Mikulits, Wolfgang [Department of Medicine I, Institute of Cancer Research, Medical University of Vienna, Borschkegasse 8a (Austria); Quereshi, Rizwana Aleem [Department of Plant Sciences, Quaid-i-Azam University Islamabad (Pakistan); Knasmueller, Siegfried; Grusch, Michael [Department of Medicine I, Institute of Cancer Research, Medical University of Vienna, Borschkegasse 8a (Austria); Kopp, Brigitte [Department of Pharmacognosy, Faculty of Life Sciences, University of Vienna, Althanstrasse 14 (Austria); Krupitza, Georg, E-mail: georg.krupitza@meduniwien.ac.at [Institute of Clinical Pathology, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria)

    2010-01-05

    Berberis lycium Royle (Berberidacea) from Pakistan and its alkaloids berberine and palmatine have been reported to possess beneficial pharmacological properties. In the present study, the anti-neoplastic activities of different B. lycium root extracts and the major constituting alkaloids, berberine and palmatine were investigated in p53-deficient HL-60 cells. The strongest growth inhibitory and pro-apoptotic effects were found in the n-butanol (BuOH) extract followed by the ethyl acetate (EtOAc)-, and the water (H{sub 2}O) extract. The chemical composition of the BuOH extract was analyzed by TLC and quantified by HPLC. 11.1 {mu}g BuOH extract (that was gained from 1 mg dried root) contained 2.0 {mu}g berberine and 0.3 {mu}g/ml palmatine. 1.2 {mu}g/ml berberine inhibited cell proliferation significantly, while 0.5 {mu}g/ml palmatine had no effect. Berberine and the BuOH extract caused accumulation of HL-60 cells in S-phase. This was preceded by a strong activation of Chk2, phosphorylation and degradation of Cdc25A, and the subsequent inactivation of Cdc2 (CDK1). Furthermore, berberine and the extract inhibited the expression of the proto-oncogene cyclin D1. Berberine and the BuOH extract induced the acetylation of {alpha}-tubulin and this correlated with the induction of apoptosis. The data demonstrate that berberine is a potent anti-neoplastic compound that acts via anti-proliferative and pro-apoptotic mechanisms independent of genotoxicity.

  1. Inhibition of protein kinase C delta attenuates allergic airway inflammation through suppression of PI3K/Akt/mTOR/HIF-1 alpha/VEGF pathway.

    Directory of Open Access Journals (Sweden)

    Yun Ho Choi

    Full Text Available Vascular endothelial growth factor (VEGF is supposed to contribute to the pathogenesis of allergic airway disease. VEGF expression is regulated by a variety of stimuli such as nitric oxide, growth factors, and hypoxia-inducible factor-1 alpha (HIF-1α. Recently, inhibition of the mammalian target of rapamycin (mTOR has been shown to alleviate cardinal asthmatic features, including airway hyperresponsiveness, eosinophilic inflammation, and increased vascular permeability in asthma models. Based on these observations, we have investigated whether mTOR is associated with HIF-1α-mediated VEGF expression in allergic asthma. In studies with the mTOR inhibitor rapamycin, we have elucidated the stimulatory role of a mTOR-HIF-1α-VEGF axis in allergic response. Next, the mechanisms by which mTOR is activated to modulate this response have been evaluated. mTOR is known to be regulated by phosphoinositide 3-kinase (PI3K/Akt or protein kinase C-delta (PKC δ in various cell types. Consistent with these, our results have revealed that suppression of PKC δ by rottlerin leads to the inhibition of PI3K/Akt activity and the subsequent blockade of a mTOR-HIF-1α-VEGF module, thereby attenuating typical asthmatic attack in a murine model. Thus, the present data indicate that PKC δ is necessary for the modulation of the PI3K/Akt/mTOR signaling cascade, resulting in a tight regulation of HIF-1α activity and VEGF expression. In conclusion, PKC δ may represent a valuable target for innovative therapeutic treatment of allergic airway disease.

  2. Rapid component I(Kr) of cardiac delayed rectifier potassium currents in guinea-pig is inhibited by alpha(1)-adrenoreceptor activation via protein kinase A and protein kinase C-dependent pathways.

    Science.gov (United States)

    Wang, Sen; Xu, Dong-Jie; Cai, Jing-Bo; Huang, Yuan-Zhu; Zou, Jian-Gang; Cao, Ke-Jiang

    2009-04-17

    Ventricular tachyarrhythmias are often precipitated by physical or emotional stress, indicating a link between increased adrenergic stimulation and cardiac ion channel activity. Human ether-a-go-go related gene (hERG) potassium channels conduct the rapid component of delayed rectifier potassium current, I(kr), a crucial component for action potential repolarization. To evaluate the correlation between increased alpha(1)-adrenergic activity and the rapid component of cardiac I(kr), whole-cell patch-clamp recording was performed in isolated guinea-pig ventricular myocytes. Stimulation of alpha(1)-adrenoceptors using phenylephrine (0.1 nM-100 microM) reduced I(kr) current in a dose-dependent manner at 37 degrees C. Phenylephrine (0.1 microM) reduced I(kr) current to 66.83+/-3.16%. Chelerythrine (1 microM), a specific inhibitor of protein kinase C (PKC) completely inhibited the changes in I(kr) trigged by 0.1 microM phenylephrine. KT5720 (2.5 microM), a specific inhibitor of protein kinase A (PKA) partially inhibited the current decrease induced by 0.1 microM phenylephrine. Both chelerythrine and KT5720 drastically reduced the phenylephrine-induced effects, indicating possible involvement of PKC and PKA in the alpha(1)-adrenergic inhibition of I(kr). Our data suggest a link between I(kr) and the alpha(1)-adrenoceptor, involving activation of PKC and PKA in arrhythmogenesis.

  3. Dopamine Cytotoxicity Involves Both Oxidative and Nonoxidative Pathways in SH-SY5Y Cells: Potential Role of Alpha-Synuclein Overexpression and Proteasomal Inhibition in the Etiopathogenesis of Parkinson's Disease

    Directory of Open Access Journals (Sweden)

    Kalpita Banerjee

    2014-01-01

    Full Text Available Background. The cytotoxic effects of dopamine (DA on several catecholaminergic cell lines involve DA oxidation products like reactive oxygen species (ROS and toxic quinones and have implications in the pathogenesis of sporadic Parkinson's disease (PD. However, many molecular details are yet to be elucidated, and the possible nonoxidative mechanism of dopamine cytotoxicity has not been studied in great detail. Results. Cultured SH-SY5Y cells treated with DA (up to 400 μM or lactacystin (5 μM or DA (400 μM plus N-acetylcysteine (NAC, 2.5 mM for 24 h are processed accordingly to observe the cell viability, mitochondrial dysfunctions, oxidative stress parameters, proteasomal activity, expression of alpha-synuclein gene, and intracellular accumulation of the protein. DA causes mitochondrial dysfunction and extensive loss of cell viability partially inhibited by NAC, potent inhibition of proteasomal activity marginally prevented by NAC, and overexpression with accumulation of intracellular alpha-synuclein partially preventable by NAC. Under similar conditions of incubation, NAC completely prevents enhanced production of ROS and increased formation of quinoprotein adducts in DA-treated SH-SY5Y cells. Separately, proteasomal inhibitor lactacystin causes accumulation of alpha-synuclein as well as mitochondrial dysfunction and cell death. Conclusions. DA cytotoxicity includes both oxidative and nonoxidative modes and may involve overexpression and accumulation of alpha-synuclein as well as proteasomal inhibition.

  4. Inhibition of ileal and colonic ornithine decarboxylase activity by alpha-difluoromethylornithine in rats: transient atrophic changes and loss of postresectional adaptive growth.

    Science.gov (United States)

    Kingsnorth, A N; Abu-Khalaf, M; LaMuraglia, G M; McCann, P P; Diekema, K A; Ross, J S; Malt, R A

    1986-06-01

    To determine the role of putrescine synthesis in adaptive hyperplasia of the ileum and colon, DL-alpha-difluoromethylornithine (DFMO), an enzyme-activated, irreversible inhibitor of ornithine decarboxylase (ODC), the enzyme controlling putrescine biosynthesis, was fed to rats after excision of the proximal half of the small bowel. A rise in ODC activity (280% in the proximal ileum, 62% in the proximal colon) and a rise in putrescine content (220% in the proximal ileum, 250% in the proximal colon) normally accompanied characteristic cytochemical adaptive increases in the ileum and colon at day 6. Inclusion of 1% DFMO (2.1 gm/kg/day) in drinking water for 12 hours before operation and for 14 days thereafter decreased ODC activity by 85% to 96%, reduced levels of putrescine and spermidine and measurements of the adaptive response by 50% in the ileum, and abolished the adaptive response in the colon. During the first 10 days of DFMO feeding, villous atrophy and other hypoplastic changes occurred in control rats, but by 14 days of DFMO feeding atrophy and hypoplasia were no longer present. Although DFMO inhibits adaptive hyperplasia occurring in the ileum and colon of rats after resection of the proximal half of the small bowel, spontaneous recovery of villous atrophy occurs during further DFMO feeding and may protect the host during chemotherapy.

  5. Enzyme-assisted extraction of phenolics from winemaking by-products: Antioxidant potential and inhibition of alpha-glucosidase and lipase activities.

    Science.gov (United States)

    de Camargo, Adriano Costa; Regitano-d'Arce, Marisa Aparecida Bismara; Biasoto, Aline Camarão Telles; Shahidi, Fereidoon

    2016-12-01

    Phenolics in food and agricultural processing by-products exist in the soluble and insoluble-bound forms. The ability of selected enzymes in improving the extraction of insoluble-bound phenolics from the starting material (experiment I) or the residues containing insoluble-bound phenolics (experiment II) were evaluated. Pronase and Viscozyme improved the extraction of insoluble-bound phenolics as evaluated by total phenolic content, antioxidant potential as determined by ABTS and DPPH assays, and hydroxyl radical scavenging capacity, reducing power as well as evaluation of inhibition of alpha-glucosidase and lipase activities. Viscozyme released higher amounts of gallic acid, catechin, and prodelphinidin dimer A compared to Pronase treatment. Furthermore, p-coumaric and caffeic acids, as well as procyanidin dimer B, were extracted with Viscozyme but not with Pronase treatment. Solubility plays an important role in the bioavailability of phenolic compounds, hence this study may assist in better exploitation of phenolics from winemaking by-products as functional food ingredients and/or supplements.

  6. Venlafaxine inhibits the upregulation of plasma tumor necrosis factor-alpha (TNF-α) in the Chinese patients with major depressive disorder: a prospective longitudinal study.

    Science.gov (United States)

    Li, Zezhi; Qi, Dake; Chen, Jun; Zhang, Chen; Yi, Zhenghui; Yuan, Chengmei; Wang, Zuowei; Hong, Wu; Yu, Shunying; Cui, Donghong; Fang, Yiru

    2013-01-01

    Although tumor necrosis factor-alpha (TNF-α) has been recognized to be involved in the pathogenesis of major depressive disorder (MDD) for a long time, only few studies so far investigated the effects of antidepressant, venlafaxine on TNF-α and the results are inconsistent. Moreover, the association between plasma TNF-α levels and suicide accompanied with MDD is entirely unknown. To elucidate these relationships, in the present study, 64 first-episode drug-naïve MDD patients and 64 matched healthy controls were recruited. Total 61 MDD patients received 8-week venlafaxine treatment and they were divided into responders and non-responders according to the reduction rate of HRSD-17. Prior to venlafaxine treatment, both responders and non-responders shared a similar plasma TNF-α (p=0.33), which was significantly decreased following venlafaxine treatment (pTNF-α (p=0.01), which was associated with the greater reduction rate of HRSD-17 (B=1.02, p=0.01). In addition, the plasma TNF-α levels were equally higher in both suicidal and non-suicidal MDD patients (p=0.84) compared to the healthy controls on admission (p=0.001, p=0.03, respectively). Together, our data suggest that MDD per se rather than suicide is associated with the elevated plasma TNF-α, which can be inhibited with venlfaxine monotherapy. The extent of TNF-α reduction may be associated with the efficiency of venlafaxine.

  7. Effect of resveratrol and beta-sitosterol in combination on reactive oxygen species and prostaglandin release by PC-3 cells.

    Science.gov (United States)

    Awad, Atif B; Burr, Andrew T; Fink, Carol S

    2005-03-01

    The objective of this project was to identify some possible mechanisms by which two common phytochemicals, resveratrol and beta-sitosterol, inhibit the growth of human prostate cancer PC-3 cells. These mechanisms include the effect of the phytochemicals on apoptosis, cell cycle progression, prostaglandin synthesis and the production of reactive oxygen species (ROS). Prostaglandins have been known to play a role in regulating cell growth and apoptosis. PC-3 cells were supplemented with 50 microM resveratrol or 16 microM beta-sitosterol alone or in combination for up to 5 days. Phytochemical supplementation resulted in inhibition in cell growth. beta-Sitosterol was more potent than resveratrol and the combination of the two resulted in greater inhibition than supplementation with either alone. Long-term supplementation with resveratrol or beta-sitosterol elevated basal prostaglandin release but beta-sitosterol was much more potent than resveratrol in this regard. beta-Sitosterol was more effective than resveratrol in inducing apoptosis and the combination had an intermediate effect after 1 day of supplementation. Cells supplemented with resveratrol were arrested at the G1 phase and at the G2/M phase in the case of beta-sitosterol while the combination resulted in cell arrest at the two phases of the cell cycle. beta-Sitosterol increased ROS production while resveratrol decreased ROS production. The combination of the two phytochemicals resulted in an intermediate level of ROS. The observed changes in prostaglandin levels and ROS production by these two phytochemicals may suggest their mediation in the growth inhibition. The reduction in ROS level and increase by resveratrol supplementation in PC-3 cells reflects the antioxidant properties of resveratrol. It was concluded that these phytochemicals may induce the inhibition of tumor growth by stimulating apoptosis and arresting cells at different locations in the cell cycle and the mechanism may involve alterations in

  8. Impact of prostaglandin glaucoma drops on platelet-activating factor action: an in vitro study

    Directory of Open Access Journals (Sweden)

    Moschos MM

    2016-12-01

    Full Text Available Marilita M Moschos,1 Eirini Nitoda,1 Irini P Chatziralli,1 Georgios D Panos,2 Constantinos A Demopoulos3 11st Department of Ophthalmology, Medical School, National and Kapodistrian University of Athens, Athens, Greece; 2Department of Ophthalmology, Geneva University Hospitals (HUG, University of Geneva, Geneva, Switzerland; 3Laboratory of Biochemistry, National and Kapodistrian University of Athens, Athens, Greece Aim: The aim of this study was to investigate the effect of different prostaglandin analogs on platelet-activating factor (PAF levels.Methods: Three prostaglandin analogs were selected: bimatoprost 0.3 mg/mL, latanoprost 50 µg/mL, and tafluprost 15 µg/mL. Each drug sample was tested for its ability to cause platelet aggregation, which was measured as PAF-induced aggregation, before and after the addition of various concentrations of the examined sample, creating a linear curve of percentage inhibition (ranging from 0% to 100% versus different concentrations of the sample. The concentration of the sample that inhibited 50% PAF-induced aggregation was calculated based on this curve, and this value was defined as IC50. In addition, the effect of eye drops on PAF metabolism was examined, through an in vitro analysis on PAF basic metabolic enzymes (PAF-cholinephosphotransferase, PAF-acetyl-CoA:1-O-alkyl-sn-glycero-3-phosphocholine acetyltransferase, and PAF-acetylhydrolase.Results: The IC50 values for Lumigan UD® (bimatoprost 0.3 mg/mL, Monoprost® (latanoprost 50 µg/mL, and Saflutan (tafluprost 15 µg/mL were 8.7, 0.28, and 1.4 µg/mL, respectively.Discussion: All three prostaglandin analogs suspended PAF, but bimatoprost induced the most potent inhibition, compared to tafluprost and to the weak effect of latanoprost. Keywords: glaucoma, platelet-activating factor, prostaglandin analogs, treatment, platelet aggregation

  9. Muscularis mucosae contraction evokes colonic secretion via prostaglandin synthesis and nerve stimulation.

    Science.gov (United States)

    Percy, W H; Fromm, T H; Wangsness, C E

    2003-02-01

    This in vitro study tested the hypothesis that muscularis mucosae contractile activity contributes to rabbit colonic mucosal function by mechanisms other than simple mechanical deformation of the epithelium. Experiments were performed by using a technique that allows simultaneous recording of muscle activity and transmucosal potential difference, a measure of epithelial ion transport. ATP, bradykinin, histamine, PGE(2), PGF(1alpha), and PGF(2alpha) elicited muscularis mucosae contractions that were resistant to atropine and TTX. Only ATP-induced contractions were indomethacin sensitive, and only those to dimethylphenylpiperazinium iodide (DMPP) were reduced by atropine. All agonist-evoked increases in transmucosal potential difference were atropine resistant, and, with the exception of those to PGE(2), PGF(2alpha), and VIP, they were also TTX sensitive. Mucosal responses to ATP, bradykinin, and histamine were indomethacin sensitive, whereas those to DMPP, the prostaglandins, and VIP were not. When cyclooxygenase activity or the mucosal innervation was compromised, even maximal muscularis mucosae contractions did not produce large secretory responses. It is concluded that contraction-related prostaglandin synthesis and noncholinergic secretomotor neuron stimulation represent the physiological transduction mechanism through which muscularis mucosae motor activity is translated into mucosal secretion.

  10. Tritium labeled amino acid conjugates of prostaglandins and thromboxanes as labeled ligands in prostanoid radioimmunoassay

    Energy Technology Data Exchange (ETDEWEB)

    Sautebin, L.; Kindahl, H.; Kumlin, M.; Granstroem, E.

    1985-09-01

    Conjugates of prostaglandins and thromboxanes with tritium labeled amino acids were prepared and employed as labeled ligands in prostaglandin and thromboxane radioimmunoassays. Assays for PGF2 alpha, 15-keto-13, 14-dihydro-PGF2 alpha, TXB2 and 15-keto-13,14-dihydro-TXB2 were evaluated in comparative studies using either these heterologous ligands or the corresponding homologous tritiated eicosanoid as tracers. Binding properties for the respective antibodies were found to be similar using either tracer. Three biological studies were also conducted, viz. study of the release of TXB2 during collagen induced platelet aggregation, of 15-keto-13,14-dihydro-TXB2 during guinea pig pulmonary anaphylaxis, and of PGF2 alpha during bovine luteolysis. The analyses gave comparable results using either the heterologous or the homologous assay. Thus, this type of labeled prostanoid conjugates may serve as a convenient alternative to homologous tracers in radioimmunoassay. Heterologous tracers may even in certain cases provide the only simple solution to the problem of preparing a labeled ligand of high specific activity.

  11. Control of cell cycle by metabolites of prostaglandin D2 through a non-cAMP mediated mechanism

    Science.gov (United States)

    Hughes-Fulford, M.; Fukushima, M.

    1993-01-01

    The dehydration products of PGD2, 9-deoxy-9 prostaglandin D2(PGJ2), 9-deoxy-delta 9, delta 12, delta 13 dehydroprostaglandin D2 (delta 12 PGJ2), and PGA2 all contain an unsaturated cyclopentenone structure which is characteristic of prostaglandins which effectively inhibit cell growth. It has been suggested that the action of the inhibitory prostaglandins may be through a cAMP mechanism. In this study, we use S49 wild type (WT) and adenylate cyclase variant (cyc-) cells to show that PGD2 and PGJ2 are not acting via a cyclic AMP mechanism. First, the increase in cyclic AMP in wild type S-49 cells is not proportional to its effects on DNA synthesis. More importantly, when S-49 cyc- cells were exposed to PGJ2, the adenylate cyclase (cyc-) mutant had decreased DNA synthesis with no change in its nominal cAMP content. Short-term (2 hours or less) exposure of the cyc- cells to prostaglandin J2 caused an inhibition of DNA synthesis. PGJ2 caused cytolysis at high concentrations. Long-term exposure (>14 hrs) of the cells to PGJ2, delta 12PGJ2 or delta 12, delta 14PGJ2 caused a cell cycle arrest in G1 demonstrating a cell cycle specific mechanism of action for growth inhibition by naturally occurring biological products independent of cAMP.

  12. Alpha Thalassemia

    Science.gov (United States)

    Alpha Thalassemia Physicians often mistake alpha thalassemia trait for iron deficiency anemia and incorrectly prescribe iron supplements that have no effect 1 on the anemia. αα αα Normal alpha ...

  13. Chronic stimulation of uterine prostaglandin synthesis during cervical ripening before the onset of labor.

    Science.gov (United States)

    Keirse, M J; Thiery, M; Parewijck, W; Mitchell, M D

    1983-05-01

    Concentrations of 13,14-dihydro-15-keto-PGF2 alpha (PGFM) were measured in plasma of six carefully selected primigravid women with an unripe cervix at term before and at various intervals after extra-amniotic insertion of a Foley catheter with or without methylhydroxyethylcellulose (Tylose) gel. The procedure caused an acute elevation of PGFM levels within 5 min (P less than 0.025), which was maintained for at least 6 hours in the absence of uterine activation at 179 +/- 32% of the initial values (P less than 0.01). Extra-amniotic administration of Tylose gel caused an increase in PGFM levels which was both higher and more prolonged (greater than 12 hours) than insertion of a Foley catheter alone. The observations indicate that cervical ripening without concomitant uterine activation is associated with an increase in PGFM levels. They also demonstrate that prolonged activation of (intra) uterine prostaglandin synthesis may occur several hours before the onset of labor-like uterine activity. A chance finding further suggests that spontaneous rupture of the membranes too may be preceeded by an increase in (intra) uterine prostaglandin synthesis. In their totality these observations lend strong support to the proposition that an increase in (intra) uterine prostaglandin production is a prerequisite to rather than a consequence of the initiation of labor.

  14. Antifibrotic effects of noscapine through activation of prostaglandin E2 receptors and protein kinase A.

    Science.gov (United States)

    Kach, Jacob; Sandbo, Nathan; La, Jennifer; Denner, Darcy; Reed, Eleanor B; Akimova, Olga; Koltsova, Svetlana; Orlov, Sergei N; Dulin, Nickolai O

    2014-03-14

    Myofibroblast differentiation is a key process in the pathogenesis of fibrotic disease. We have shown previously that differentiation of myofibroblasts is regulated by microtubule polymerization state. In this work, we examined the potential antifibrotic effects of the antitussive drug, noscapine, recently found to bind microtubules and affect microtubule dynamics. Noscapine inhibited TGF-β-induced differentiation of cultured human lung fibroblasts (HLFs). Therapeutic noscapine treatment resulted in a significant attenuation of pulmonary fibrosis in the bleomycin model of the disease. Noscapine did not affect gross microtubule content in HLFs, but inhibited TGF-β-induced stress fiber formation and activation of serum response factor without affecting Smad signaling. Furthermore, noscapine stimulated a rapid and profound activation of protein kinase A (PKA), which mediated the antifibrotic effect of noscapine in HLFs, as assessed with the PKA inhibitor, PKI. In contrast, noscapine did not activate PKA in human bronchial or alveolar epithelial cells. Finally, activation of PKA and the antifibrotic effect of noscapine in HLFs were blocked by the EP2 prostaglandin E2 receptor antagonist, PF-04418948, but not by the antagonists of EP4, prostaglandin D2, or prostacyclin receptors. Together, we demonstrate for the first time the antifibrotic effect of noscapine in vitro and in vivo, and we describe a novel mechanism of noscapine action through EP2 prostaglandin E2 receptor-mediated activation of PKA in pulmonary fibroblasts.

  15. 2,3-Dihydro-1-benzofuran-5-ols as analogues of alpha-tocopherol that inhibit in vitro and ex vivo lipid autoxidation and protect mice against central nervous system trauma.

    Science.gov (United States)

    Grisar, J M; Bolkenius, F N; Petty, M A; Verne, J

    1995-02-03

    A series of alpha-tocopherol analogues was synthesized with potential therapeutic value for such pathological conditions as stroke and trauma. A set of criteria such as the inhibition of in vitro lipid peroxidation, superoxyl radical scavenging, and brain penetration, as measured by ex vivo inhibition of lipid peroxidation, was applied to select the most effective compound. 2,3-Dihydro-2,2,4,6,7-pentamethyl-3-[(4-methylpiperazino)methyl]-1 - benzofuran-5-ol dihydrochloride (22) was selected because of its superior antioxidant properties and better brain penetration. This compound also protected mice against the effects of head injury. The criteria thus turned out to be useful for the characterization of a neuroprotective analogue of alpha-tocopherol.

  16. Role of Prostaglandins in Neuroinflammatory and Neurodegenerative Diseases

    Science.gov (United States)

    Lima, Isabel Vieira de Assis; Bastos, Leandro Francisco Silva; Limborço-Filho, Marcelo; Fiebich, Bernd L.; de Oliveira, Antonio Carlos Pinheiro

    2012-01-01

    Increasing data demonstrates that inflammation participates in the pathophysiology of neurodegenerative diseases. Among the different inflammatory mediators involved, prostaglandins play an important role. The effects induced by prostaglandins might be mediated by activation of their known receptors or by nonclassical mechanisms. In the present paper, we discuss the evidences that link prostaglandins, as well as the enzymes that produce them, to some neurological diseases. PMID:22778499

  17. Extra-amniotic prostaglandin E2 and the unfavourable cervix.

    Science.gov (United States)

    Shepherd, J; Sims, C; Craft, I

    1976-10-02

    A small dose of prostaglandin E2 suspended in a viscous medium was instilled as a single application into the extra-amniotic space of patients with unfavourable induction features the day before planned induction in an attempt to improve the condition of the cervix. Two groups of 15 patients were studied, one receiving prostaglandin E2 250 mug suspended in methyl ethyl cellulose ('Tylose') 6% solution, and the other tylose alone. Cervical status did not change in those receiving tylose alone, whereas a significant improvement occurred in 14 out of 15 patients receiving the prostaglandin. Labour began before formal induction in 1 patient receiving tylose and in 8 receiving prostaglandin.

  18. Does prostaglandin D2 hold the cure to male pattern baldness?

    Science.gov (United States)

    Nieves, Ashley; Garza, Luis A

    2014-04-01

    Lipids in the skin are the most diverse in the entire human body. Their bioactivity in health and disease is underexplored. Prostaglandin D2 has recently been identified as a factor which is elevated in the bald scalp of men with androgenetic alopecia (AGA) and has the capacity to decrease hair lengthening. An enzyme which synthesizes it, prostaglandin D2 synthase (PTGDS or lipocalin-PGDS), is hormone responsive in multiple other organs. PGD2 has two known receptors, GPR44 and PTGDR. GPR44 was found to be necessary for the decrease in hair growth by PGD2 . This creates an exciting opportunity to perhaps create novel treatments for AGA, which inhibit the activity of PTGDS, PGD2 or GPR44. This review discusses the current knowledge surrounding PGD2 , and future steps needed to translate these findings into novel therapies for patients with AGA.

  19. Alpha lipoic acid protects lens from H2O2-induced cataract by inhibiting apoptosis of lens epithelial cells and inducing activation of anti-oxidative enzymes

    Institute of Scientific and Technical Information of China (English)

    Yun Li; Ya-Zhen Liu; Jing-Ming Shi; Song-Bai Jia

    2013-01-01

    Objective: To determine whether alpha lipoic acid (LA) can effectively protect lenses from hydrogen peroxide (H2O2)-induced cataract. Methods: Lens from adult Sprague-Dawley rats were cultured in 24-well plates and treated without or with 0.2 mM of H2O2, 0.2 mM of H2O2 plus 0.5 mM, 1.0 mM, or 2.0 mM of LA for 24 h. Cataract was assessed using cross line grey scale measurement. Superoxide dismutase (SOD), glutathione (GSH-Px), lactate dehydrogenase (LDH), and malondialdehyde (MDA) activity or level in lens homogenates was measured. Apoptosis of lens epithelial cells in each group were detected by Terminal Deoxynucleotidyl Transferase dUTP Nick End Labeling (TUNEL) Assay. Results: A total of 0.2 mM of H2O2 induced obvious cataract formation and apoptosis in lens’ epithelial cells, but 0.5-2.0 mM of LA could block the effect of 0.2 mM H2O2 in inducing cataract and apoptosis. Furthermore, 0.2 mM of H2O2 significantly decreased SOD, GSH-Px, and LDH activity and significant increased MDA level in the lens, but 0.5-2.0 mM of LA blocked the effect of 0.2 mM H2O2. One mM of LA was found to be the most effective. Conclusions: LA can protect lens from H2O2-induced cataract. LA exerts protective effects through inhibition of lens’ epithelial cell apoptosis and activation of anti-oxidative enzymes.

  20. Identification of a novel compound that inhibits iNOS and COX-2 expression in LPS-stimulated macrophages from Schisandra chinensis

    Energy Technology Data Exchange (ETDEWEB)

    Lee, You Jin [Department of Horticultural Bioscience, Pusan National University, Miryang 627-706 (Korea, Republic of); Park, Sun Young [Korea BIO-IT Foundry Center, Pusan National University, Busan 609-735 (Korea, Republic of); Kim, Sun Gun; Park, Da Jung; Kang, Jum Soon [Department of Horticultural Bioscience, Pusan National University, Miryang 627-706 (Korea, Republic of); Lee, Sang Joon [Department of Microbiology, Pusan National University, Busan 609-735 (Korea, Republic of); Yoon, Sik [Department of Anatomy, School of Medicine, Pusan National University, Yangsan 626-770 (Korea, Republic of); Medical Research Center for Ischemic Tissue Regeneration, School of Medicine, Pusan National University, Yangsan 626-770 (Korea, Republic of); Kim, Young Hun [Korea BIO-IT Foundry Center, Pusan National University, Busan 609-735 (Korea, Republic of); Bae, Yoe-Sik, E-mail: yoesik@dau.ac.kr [Department of Biochemistry, College of Medicine, Dong-A University, Busan 602-714 (Korea, Republic of); Choi, Young-Whan, E-mail: ywchoi@pusan.ac.kr [Department of Horticultural Bioscience, Pusan National University, Miryang 627-706 (Korea, Republic of)

    2010-01-22

    A novel {alpha}-iso-cubebenol, which has anti-inflammatory effects in lipopolysaccharide (LPS)-treated RAW 264.7 macrophages, was isolated from the fruits of Schisandra chinensis. {alpha}-iso-cubebenol inhibited LPS-induced nitric oxide (NO) and prostaglandin E{sub 2} (PGE{sub 2}) production. Consistent with these findings, {alpha}-iso-cubebenol also reduced the LPS-induced expression of inducible nitric oxide synthase and cyclooxygenase-2 at the protein and mRNA levels in a concentration-dependent manner. {alpha}-iso-cubebenol also inhibited LPS-induced nuclear translocation of the NF-{kappa}B p65 subunit. Furthermore, {alpha}-iso-cubebenol suppressed the phosphorylation of ERK, JNK, and p38 kinase induced by LPS. Since the novel {alpha}-iso-cubebenol blocked the production of several pro-inflammatory mediators induced by LPS in macrophages, the molecule can be useful material for the development of anti-inflammatory agents against bacterial infections or endotoxin.

  1. beta-oxidation modulates metabolic competition between eicosapentaenoic acid and arachidonic acid regulating prostaglandin E(2) synthesis in rat hepatocytes-Kupffer cells

    DEFF Research Database (Denmark)

    Du, Zhen-Yu; Ma, Tao; Winterthun, Synnøve;

    2010-01-01

    The ability of n-3 PUFA to competitively inhibit the use of arachidonic acid (AA) for membrane phospholipid synthesis and prostaglandin E(2) (PGE(2)) production has been well demonstrated in single cell models. In the present study, we investigated the metabolic competition between AA and eicosap......The ability of n-3 PUFA to competitively inhibit the use of arachidonic acid (AA) for membrane phospholipid synthesis and prostaglandin E(2) (PGE(2)) production has been well demonstrated in single cell models. In the present study, we investigated the metabolic competition between AA...

  2. Putative role of prostaglandin receptor in intracerebral hemorrhage

    Directory of Open Access Journals (Sweden)

    Shekher eMohan

    2012-10-01

    Full Text Available Each year, approximately 795,000 people experience a new or recurrent stroke. Of all strokes, 84% are ischemic, 13% are intracerebral hemorrhage (ICH strokes and 3% are subarachnoid hemorrhage (SAH strokes. Despite the decreased incidence of ischemic stroke, there has been no change in the incidence of hemorrhagic stroke in the last decade. ICH is a devastating disease 37-38% of patients between the ages of 45-64 die within 30 days. In an effort to prevent ischemic and hemorrhagic strokes we and others have been studying the role of prostaglandins and their receptors. Prostaglandins are bioactive lipids derived from the metabolism of arachidonic acid. They sustain homeostatic functions and mediate pathogenic mechanisms, including the inflammatory response. Most prostaglandins are produced from specific enzymes and act upon cells via distinct G-protein coupled receptors. The presence of multiple prostaglandin receptor’s cross-reactivity and coupling to different signal transduction pathways allow differentiated cells to respond to prostaglandins in a unique manner. Due to the number of prostaglandin receptors, prostaglandin-dependent signaling can function either to promote neuronal survival or injury following acute excitotoxicity, hypoxia, and stress induced by ICH. To better understand the mechanisms of neuronal survival and neurotoxicity mediated by prostaglandin receptors, it is essential to understand downstream signaling. Several groups including ours have discovered unique roles for prostaglandin receptors in rodent models of ischemic stroke, excitotoxicity, and Alzheimer disease, highlighting the emerging role of prostaglandin receptor signaling in hemorrhagic stroke with a focus on cyclic-adenosine monophosphate (cAMP and calcium (Ca2+ signaling. We review current ICH data and discuss future directions notably on prostaglandin receptors, which may lead to the development of unique therapeutic targets against hemorrhagic stroke and

  3. Effect of forskolin on alterations of vascular permeability induced with bradykinin, prostaglandin E1, adenosine, histamine and carrageenin in rats.

    Science.gov (United States)

    Sugio, K; Daly, J W

    1983-07-01

    The effect of the diterpene forskolin on vascular permeability alone and in combination with bradykinin, prostaglandin E1, adenosine or histamine has been investigated in rats. Vascular permeability in rat skin was measured using [125I]-labelled bovine serum albumin ([125I]BSA) as a tracer. In addition, the effect of forskolin on footpad edema induced by the injection of a mixture of 2% carrageenin was determined. Forskolin caused a marked potentiation of the increase in vascular permeability in rat skin elicited by the intradermal injection of histamine or bradykinin. However, forskolin caused a significant suppression of the prostaglandin E1-induced vascular permeability response and at a low concentration suppressed the response to adenosine. Forskolin greatly potentiated the footpad edema induced with carrageenin in rats. Intravenous administration of the enzyme bromelain, which reduces plasma kininogen levels, inhibited the footpad edema induced with carrageenin or with a mixture of carrageenin and forskolin. Parenteral administration of a prostaglandin synthetase inhibitor, indomethacin, suppressed the footpad edema induced with carrageenin, but did not inhibit the footpad edema induced with a mixture of carrageenin and forskolin. An antihistamine, cyproheptadine, had no effect on carrageenin-induced footpad edema either in the presence or absence of forskolin. These results suggest that both bradykinin and prostaglandins are essential for the development of carrageenin-induced footpad edema and that bradykinin plays an important role in the potentiative effect of forskolin on footpad edema induced with carrageenin in rats.

  4. Synergistic inhibitory effect of ascorbic acid and acetylsalicylic acid on prostaglandin E2 release in primary rat microglia.

    Science.gov (United States)

    Fiebich, Bernd L; Lieb, Klaus; Kammerer, Norbert; Hüll, Michael

    2003-07-01

    Ascorbic acid (vitamin C) has been suggested to protect cerebral tissue in a variety of pathophysiological situations such as head trauma, ischemia or Alzheimer's disease. Most of these protective actions have been attributed to the antioxidative capacity of ascorbic acid. Besides the presence of elevated levels of oxygen radicals, prostaglandins produced by neurones and microglial cells seem to play an important role in prolonged tissue damage. We investigated whether ascorbic acid alone inhibits prostaglandin E2 (PGE2) synthesis and may augment the inhibitory effect of acetylsalicylic acid on prostaglandin synthesis. Ascorbic acid dose-dependently inhibited PGE2 synthesis in lipopolysaccharide-treated primary rat microglial cells (IC50 = 3.70 micro m). In combination with acetylsalicylic acid (IC50 = 1.85 micro m), ascorbic acid augmented the inhibitory effect of acetylsalicylic acid on PGE2 synthesis (IC50 = 0.25 micro m in combination with 100 micro m ascorbic acid). Ascorbic acid alone or in combination with acetylsalicylic acid did not inhibit cyclooxygenase-2 (COX-2) protein synthesis but inhibited COX-2 enzyme activity. Our results show that ascorbic acid and acetylsalicylic acid act synergistically in inhibiting PGE2 synthesis, which may help to explain a possible protective effect of ascorbic acid in various brain diseases.

  5. Strong inhibition of TNF-alpha production and inhibition of IL-8 and COX-2 mRNA expression in monocyte-derived macrophages by RWJ 67657, a p38 mitogen-activated protein kinase (MAPK) inhibitor

    NARCIS (Netherlands)

    Westra, J; Doornbos-van der Meer, B; de Boer, Peter; van Leeuwen, MA; van Rijswijk, Martin; Limburg, PC

    2004-01-01

    In inflammatory processes, the p38 mitogen-activated protein kinase ( MAPK) signal transduction route regulates production and expression of cytokines and other inflammatory mediators. Tumor necrosis factor alpha (TNF-alpha) is a pivotal cytokine in rheumatoid arthritis and its production in macroph

  6. Prostaglandin modulation of mouse and human sperm capacitation.

    Science.gov (United States)

    Herrero, M B; Viggiano, J M; Boquet, M; Gimeno, M A

    1997-09-01

    To determine whether prostaglandins produce a capacitation and/or acrosome reaction, the effect of prostaglandins on capacitated mouse spermatozoa and the effect of prostaglandin pre-incubation on human and mouse spermatozoa were studied. Prostaglandins did not induce an acrosome reaction in capacitated mouse sperm. PGE1 pre-incubation in a protein-free medium enhanced acrosome loss of mouse sperm challenged with A-23187 or solubilized mouse zona pellucida. Human sperm were pre-incubated in media containing prostaglandins, and an acrosome reaction was induced with calcium ionophore or human follicular fluid. PGE1 pre-incubation enhanced acrosome loss by human sperm when the action was induced with calcium ionophore, but had no effect on follicular fluid induction. We conclude that PGE1 acts as a capacitating factor in vitro for mouse spermatozoa, and enhances acrosome-reaction induction with calcium ionophore in human spermatozoa.

  7. Ketamine inhibits tumor necrosis factor-alpha and interleukin-6 gene expressions in lipopolysaccharide-stimulated macrophages through suppression of toll-like receptor 4-mediated c-Jun N-terminal kinase phosphorylation and activator protein-1 activation.

    Science.gov (United States)

    Wu, Gone-Jhe; Chen, Ta-Liang; Ueng, Yune-Fang; Chen, Ruei-Ming

    2008-04-01

    Our previous study showed that ketamine, an intravenous anesthetic agent, has anti-inflammatory effects. In this study, we further evaluated the effects of ketamine on the regulation of tumor necrosis factor-alpha (TNF-alpha) and interlukin-6 (IL-6) gene expressions and its possible signal-transducing mechanisms in lipopolysaccharide (LPS)-activated macrophages. Exposure of macrophages to 1, 10, and 100 microM ketamine, 100 ng/ml LPS, or a combination of ketamine and LPS for 1, 6, and 24 h was not cytotoxic to macrophages. A concentration of 1000 microM of ketamine alone or in combined treatment with LPS caused significant cell death. Administration of LPS increased cellular TNF-alpha and IL-6 protein levels in concentration- and time-dependent manners. Meanwhile, treatment with ketamine concentration- and time-dependently alleviated the enhanced effects. LPS induced TNF-alpha and IL-6 mRNA syntheses. Administration of ketamine at a therapeutic concentration (100 microM) significantly inhibited LPS-induced TNF-alpha and IL-6 mRNA expressions. Application of toll-like receptor 4 (TLR4) small interfering (si)RNA into macrophages decreased cellular TLR4 levels. Co-treatment of macrophages with ketamine and TLR4 siRNA decreased the LPS-induced TNF-alpha and IL-6 productions more than alone administration of TLR4 siRNA. LPS stimulated phosphorylation of c-Jun N-terminal kinase and translocation of c-Jun and c-Fos from the cytoplasm to nuclei. However, administration of ketamine significantly decreased LPS-induced activation of c-Jun N-terminal kinase and translocation of c-Jun and c-Fos. LPS increased the binding of nuclear extracts to activator protein-1 consensus DNA oligonucleotides. Administration of ketamine significantly ameliorated LPS-induced DNA binding activity of activator protein-1. Therefore, a clinically relevant concentration of ketamine can inhibit TNF-alpha and IL-6 gene expressions in LPS-activated macrophages. The suppressive mechanisms occur through

  8. Interactions between ADH and prostaglandins in isolated erythrocyte-perfused rat kidney

    Energy Technology Data Exchange (ETDEWEB)

    Lieberthal, W.; Vasilevsky, M.L.; Valeri, C.R.; Levinsky, N.G.

    1987-02-01

    Interactions between antidiuretic hormone (ADH) and renal prostaglandins in the regulation of sodium reabsorption and urinary concentrating ability were studied in isolated erythrocyte-perfused rat kidneys (IEPK). In this model, hemodynamic characteristics are comparable to those found in vivo, and tubular morphology is preserved throughout the period of perfusion. (Deamino)-D-arginine vasopressin (dDAVP) markedly reduced fractional sodium excretion (FE/sub Na/) in the IEPK. After indomethacin, FE/sub Na/ fell still further. In the absence of dDAVP indomethacin had no effect on sodium excretion. dDAVP increased urine osmolality in the IEPK. When prostaglandin synthesis was blocked with indomethacin, urinary osmolality increased further. In isolated kidneys perfused without erythrocytes (IPK), dDAVP decreased FE/sub Na/ from 14.5 +/- 1.8% to 9.6 +/- 1.2%. dDAVP increased urine osmolality only modestly in the IPK and indomethacin did not increase concentrating ability further. Thus the IEPK (unlike the IPK) can excrete markedly hypertonic urine in response to ADH. ADH also enhances tubular reabsorption of sodium in the IEPK. Prostaglandins inhibit both these actions of ADH but do not directly affect sodium excretion in the absence of the hormone. Prostaglandius were measured by radioimmunoassay.

  9. Prostaglandin-E-2 enhances EPO-mediated STAT5 transcriptional activity by serine phosphorylation of CREB

    NARCIS (Netherlands)

    Boer, AK; Drayer, AL; Rui, H; Vellenga, E

    2002-01-01

    Erythroid colony formation in response to erythropoietin (EPO) stimulation is enhanced by costimulating the cells with prostaglandin-E-2 (PGE(2)). The present study further analyzed the underlying mechanisms and demonstrated that EPO-mediated STAT5 transactivation in the erythroid AS-E-2 cell line w

  10. Complete inhibition of the tentoxin-resistant F1-ATPase from Escherichia coli by the phytopathogenic inhibitor tentoxin after substitution of critical residues in the alpha - and beta -subunit.

    Science.gov (United States)

    Schnick, Claudia; Körtgen, Nicole; Groth, Georg

    2002-12-27

    Substitution of critical residues in the alpha- and beta-subunit can turn the typically resistant ATP synthase from the bacterium Escherichia coli into an enzyme showing high sensitivity to the phytopathogenic inhibitor tentoxin, which usually affects only certain sensitive plant species. In contrast to recent results obtained with the thermophilic F(1) (Groth, G., Hisabori, T., Lill, H., and Bald, D. (2002) J. Biol. Chem. 277, 20117-20119), substitution of a critical serine in the beta-subunit (betaSer(59)), which is supposed to provide an important intermolecular hydrogen bond in the binding site, was not sufficient on its own for conferring tentoxin sensitivity to the E. coli F(1) complex. Superimposition of the chloroplast F(1)-tentoxin inhibitor complex on a homology model of the E. coli F(1) complex provided detailed information on the critical residues in the alpha-subunit of the binding cleft and allowed us to model the binding site according to the steric requirements of the inhibitor. Substitution of the highly conserved residue alphaLeu(64) seems to be most important for allowing access of the inhibitor to the binding site. Combining this substitution with either additional replacements in the alpha-subunit (Q49A, L95A, E96Q, I273M) or the replacement of Ser(59) in the beta-subunit enhanced the sensitivity to the inhibitor and resulted in a complete inhibition of the E. coli F(1)-ATPase by the plant-specific inhibitor tentoxin.

  11. Proteinaceous alpha-araylase inhibitors

    DEFF Research Database (Denmark)

    Svensson, Birte; Fukuda, Kenji; Nielsen, P.K.;

    2004-01-01

    Proteins that inhibit alpha-amylases have been isolated from plants and microorganisms. These inhibitors can have natural roles in the control of endogenous a-amylase activity or in defence against pathogens and pests; certain inhibitors are reported to be antinutritional factors. The alpha-amylase...... inhibitors belong to seven different protein structural families, most of which also contain evolutionary related proteins without inhibitory activity. Two families include bifunctional inhibitors acting both on alpha-amylases and proteases. High-resolution structures are available of target alpha-amylases...... in complex with inhibitors from five families. These structures indicate major diversity but also some similarity in the structural basis of alpha-amylase inhibition. Mutational analysis of the mechanism of inhibition was performed in a few cases and various protein engineering and biotechnological...

  12. Prostaglandin-E2 Mediated Increase in Calcium and Phosphate Excretion in a Mouse Model of Distal Nephron Salt Wasting.

    Directory of Open Access Journals (Sweden)

    Manoocher Soleimani

    Full Text Available Contribution of salt wasting and volume depletion to the pathogenesis of hypercalciuria and hyperphosphaturia is poorly understood. Pendrin/NCC double KO (pendrin/NCC-dKO mice display severe salt wasting under basal conditions and develop profound volume depletion, prerenal renal failure, and metabolic alkalosis and are growth retarded. Microscopic examination of the kidneys of pendrin/NCC-dKO mice revealed the presence of calcium phosphate deposits in the medullary collecting ducts, along with increased urinary calcium and phosphate excretion. Confirmatory studies revealed decreases in the expression levels of sodium phosphate transporter-2 isoforms a and c, increases in the expression of cytochrome p450 family 4a isotypes 12 a and b, as well as prostaglandin E synthase 1, and cyclooxygenases 1 and 2. Pendrin/NCC-dKO animals also had a significant increase in urinary prostaglandin E2 (PGE-2 and renal content of 20-hydroxyeicosatetraenoic acid (20-HETE levels. Pendrin/NCC-dKO animals exhibit reduced expression levels of the sodium/potassium/2chloride co-transporter 2 (NKCC2 in their medullary thick ascending limb. Further assessment of the renal expression of NKCC2 isoforms by quantitative real time PCR (qRT-PCR reveled that compared to WT mice, the expression of NKCC2 isotype F was significantly reduced in pendrin/NCC-dKO mice. Provision of a high salt diet to rectify volume depletion or inhibition of PGE-2 synthesis by indomethacin, but not inhibition of 20-HETE generation by HET0016, significantly improved hypercalciuria and salt wasting in pendrin/NCC dKO mice. Both high salt diet and indomethacin treatment also corrected the alterations in NKCC2 isotype expression in pendrin/NCC-dKO mice. We propose that severe salt wasting and volume depletion, irrespective of the primary originating nephron segment, can secondarily impair the reabsorption of salt and calcium in the thick ascending limb of Henle and/or proximal tubule, and reabsorption of

  13. Ethylacetate extract from Draconis Resina inhibits LPS-induced inflammatory responses in vascular smooth muscle cells and macrophages via suppression of ROS production.

    Science.gov (United States)

    Heo, Sook-Kyoung; Yi, Hyo-Seung; Yun, Hyun-Jeong; Ko, Chang-Hyun; Choi, Jae-Woo; Park, Sun-Dong

    2010-05-01

    Draconis Resina (DR) is a type of dragon's blood resin obtained from Daemomorops draco BL. (Palmae). DR has long been used as a traditional Korean herbal medicine, and is currently used in traditional clinics to treat wounds, tumors, diarrhea, and rheumatism, insect bites and other conditions. In this study, we evaluated fractionated extracts of DR to determine if they inhibited the production of interleukin-1beta (IL-1beta) and the expression of cyclooxygenase (COX)-2. The results of this analysis revealed that the ethylacetate extract of Draconis Resina (DREA) was more potent than that of other extracts. Moreover, DREA inhibited the production of nitric oxide (NO), reactive oxygen species (ROS), prostaglandin E(2) (PGE(2)), tumor necrosis factor-alpha (TNF-alpha), IL-8 and IL-6 in lipopolysaccharide (LPS)-treated human aortic smooth muscle cells (HASMC) and RAW 264.7 macrophages. Furthermore, treatment with an NADPH oxidase assembly inhibitor, AEBSF, efficiently blocked LPS-induced mitogen-activated protein kinases (MAPKs) activation, as did DREA. These findings indicate that DREA inhibits the production of NO, PGE(2), TNF-alpha, IL-8, and IL-6 by LPS via the inhibition of ROS production, which demonstrates that DREA inhibits LPS-induced inflammatory responses via the suppression of ROS production. Taken together, these results indicate that DREA has the potential for use as an anti-atherosclerosis agent.

  14. Effects of renin inhibition in systemic hypertension.

    Science.gov (United States)

    Anderson, P W; Do, Y S; Schambelan, M; Horton, R; Boger, R S; Luther, R R; Hsueh, W A

    1990-12-01

    The effect of the direct renin inhibitor enalkiren (Abbott Laboratories) was examined in 8 healthy patients with essential hypertension. With an unrestricted sodium diet, plasma renin concentration was inhibited within 10 minutes by intravenous enalkiren and remained essentially undetectable for greater than or equal to 6 hours (11.9 +/- 4 to 1.0 +/- 0.6 ng angiotensin I/ml/hour, p less than 0.05). Mean arterial blood pressure declined gradually (108 +/- 5 to 84 +/- 4 mm Hg, p = 0.02), as did plasma aldosterone concentration (14.4 +/- 3.8 to 4.4 +/- 0.8 ng/dl, p = 0.03), whereas plasma immunoreactive active renin concentration increased progressively (35 +/- 14 to 160 +/- 60 pg/ml, p greater than 0.05). Urinary excretion of the stable metabolite of prostacyclin (6-keto-prostaglandin F1 alpha) decreased slightly, but not significantly (42 +/- 10 to 33 +/- 11 ng/g creatinine, p = 0.13). The addition of a diuretic decreased baseline blood pressure and increased baseline plasma renin and aldosterone values. Blood pressure responses to enalkiren were slightly (though not significantly) greater than those observed before diuretic administration. We conclude that enalkiren is effective in decreasing blood pressure and in inhibiting the renin system, without significantly altering urinary prostacyclin excretion, in patients with essential hypertension. These results suggest that the renin system contributes to the maintenance of elevated blood pressure in some patients with essential hypertension.

  15. The prostaglandin E2 receptor EP4 is integral to a positive feedback loop for prostaglandin E2 production in human macrophages infected with Mycobacterium tuberculosis.

    Science.gov (United States)

    Nishimura, Tomoyasu; Zhao, Xiaomin; Gan, Huixian; Koyasu, Shigeo; Remold, Heinz G

    2013-09-01

    Prostaglandin E2 (PGE2) is an important biological mediator involved in the defense against Mycobacterium tuberculosis (Mtb) infection. Previously, we reported that in macrophages (Mϕs), infection with avirulent Mtb H37Ra resulted in inhibition of necrosis by an inhibitory effect on mitochondrial permeability transition via the PGE2 receptor EP2. However, human Mϕs also express EP4, a PGE2 receptor functionally closely related to EP2 that also couples to stimulatory guanine nucleotide binding protein, but the functional differences between EP2 and EP4 in Mtb-infected Mϕs have been unclear. EP4 antagonist addition to H37Ra-infected Mϕs inhibited the expression of cyclooxygenase 2 (COX2) and microsomal prostaglandin E synthase-1 (mPGES-1), which are involved in PGE2 production. Moreover, H37Ra infection induced PGE2 production through the Toll-like receptor (TLR) 2/p38 mitogen-activated protein kinase (MAPK) signaling pathway. Induction of COX2 and mPGES-1 expression by TLR2 stimulation or Mtb infection was increased after additional stimulation with EP4 agonist. Hence, in Mtb-infected Mϕs, PGE2 production induced by pathogen recognition receptors/p38 MAPK signaling is up-regulated by EP4-triggered signaling to maintain an effective PGE2 concentration.

  16. Cadmium-induced calcium release and prostaglandin E[sub 2] production in neonatal mouse calvaria are dependent on cox-2 induction and protein kinase C activation

    Energy Technology Data Exchange (ETDEWEB)

    Romare, A. (Department of Pharmacology, Faculty of Health Sciences, Univ. of Linkoeping (Sweden)); Lundholm, C.E. (Department of Pharmacology, Univ. of Linkoeping (Sweden) Astra Haessle AB, Regulatory Affairs, Moendal (Sweden))

    The mechanisms by which cadmium (Cd) causes skeletal impairment have not been fully clarified. Release of calcium from neonatal mouse calvaria in organ culture is stimulated by submicromolar concentrations of Cd, an effect that is associated with increased production of prostaglandin E[sub 2] (PGE[sub 2]). The prostaglandin-synthesising enzyme cyclooxygenase (cox) exists in two forms, one constitutive (cox-1) and the other inducible (cox-2). Cox-2 can be induced by mitogenic stimuli and inflammatory cytokines, such as parathyroid hormone (PTH), interleukin-1[alpha] and tumour necrosis factor-[alpha]. Cd potently activates protein kinase C (PKC), which in turn induces cox-2 production in several cell types. Our aim was to determine whether Cd-induced Ca release and PGE[sub 2] production in neonatal mouse calvaria involve induction of cox-2 and, if so, to ascertain whether that effect is mediated by activation of PKC. Cd dose-dependently stimulated Ca release from cultured neonatal mouse calvaria, with a maximal effect at 0.4-0.8 [mu]M. Different sensitivity was observed to Cd-induced Ca release between two breeds of mice suggesting that the susceptibility to Cd may be genetically determined. Dexamethasone (10 [mu]M) added to the culture medium abolished the Ca releasing effect of Cd, an effect not overcome by addition of arachidonic acid (10 [mu]M). The cox-2-selective inhibitors NS-398 and DFU and the less selective inhibitor meloxicam, potently impeded Cd-induced Ca release (IC[sub 50] of 1 nM, 41 nM and 7 nM, respectively) and calvarial production of PGE[sub 2]. Cd-induced and phorbol 12-myristate 13-acetate (PMA; 20 nM)-induced Ca release was inhibited by the PKC inhibitor calphostin C (0.5 [mu]M) and by NS-398. The effects of PMA and Cd on Ca release were not additive, suggesting that both operated via the PKC pathway. We suggest that Cd-induced Ca release from neonatal mouse calvaria in culture depends on induction of cox-2 that occurs via the PKC signalling

  17. Cadmium-induced calcium release and prostaglandin E{sub 2} production in neonatal mouse calvaria are dependent on cox-2 induction and protein kinase C activation

    Energy Technology Data Exchange (ETDEWEB)

    Romare, A. [Department of Pharmacology, Faculty of Health Sciences, Univ. of Linkoeping (Sweden); Lundholm, C.E. [Department of Pharmacology, Univ. of Linkoeping (Sweden)]|[Astra Haessle AB, Regulatory Affairs, Moendal (Sweden)

    1999-06-01

    The mechanisms by which cadmium (Cd) causes skeletal impairment have not been fully clarified. Release of calcium from neonatal mouse calvaria in organ culture is stimulated by submicromolar concentrations of Cd, an effect that is associated with increased production of prostaglandin E{sub 2} (PGE{sub 2}). The prostaglandin-synthesising enzyme cyclooxygenase (cox) exists in two forms, one constitutive (cox-1) and the other inducible (cox-2). Cox-2 can be induced by mitogenic stimuli and inflammatory cytokines, such as parathyroid hormone (PTH), interleukin-1{alpha} and tumour necrosis factor-{alpha}. Cd potently activates protein kinase C (PKC), which in turn induces cox-2 production in several cell types. Our aim was to determine whether Cd-induced Ca release and PGE{sub 2} production in neonatal mouse calvaria involve induction of cox-2 and, if so, to ascertain whether that effect is mediated by activation of PKC. Cd dose-dependently stimulated Ca release from cultured neonatal mouse calvaria, with a maximal effect at 0.4-0.8 {mu}M. Different sensitivity was observed to Cd-induced Ca release between two breeds of mice suggesting that the susceptibility to Cd may be genetically determined. Dexamethasone (10 {mu}M) added to the culture medium abolished the Ca releasing effect of Cd, an effect not overcome by addition of arachidonic acid (10 {mu}M). The cox-2-selective inhibitors NS-398 and DFU and the less selective inhibitor meloxicam, potently impeded Cd-induced Ca release (IC{sub 50} of 1 nM, 41 nM and 7 nM, respectively) and calvarial production of PGE{sub 2}. Cd-induced and phorbol 12-myristate 13-acetate (PMA; 20 nM)-induced Ca release was inhibited by the PKC inhibitor calphostin C (0.5 {mu}M) and by NS-398. The effects of PMA and Cd on Ca release were not additive, suggesting that both operated via the PKC pathway. We suggest that Cd-induced Ca release from neonatal mouse calvaria in culture depends on induction of cox-2 that occurs via the PKC signalling

  18. Identification and characterization of a putative human platelet thromboxane A/sub 2//prostaglandin H/sub 2/ receptor

    Energy Technology Data Exchange (ETDEWEB)

    Saussy, D.L. Jr.

    1986-01-01

    The thromboxane A/sub 2/ (TXA/sub 2/) analog, 9,11-dimethylmethano-11,12-methano-16-(3-iodo-4-hydroxyphenyl)-13,14-dihydro-13-aza-15..cap alpha beta..-omega-tetranor TXA/sub 2/ (I-PTA-OH) was characterized as a competitive antagonist of TXA/sub 2/ mimetic-induced platelet aggregation, with a K/sub d/ of 190 nM in platelet rich plasma. This antagonism was specific for the putative thromboxane A/sub 2//prostaglandin H/sub 2/ (TXA/sub 2//PGH/sub 2/) receptor, since I-PTA-OH had no inhibitory effects on platelet aggregation stimulated by agonists which act independently of TXA/sub 2//PGH/sub 2/, and did not inhibit platelet TXA/sub 2/ synthesis. (/sup 125/I)-PTA-OH binding to a particulate fraction from human platelets was saturable, displaceable, and linear with protein concentration. Scatchard analysis of equilibrium binding revealed a single class of high affinity binding sites, with a K/sub d/ of 30 +/- 4 nM and a B/sub max/ of 1.8 +/- 0.3 pmol/mg protein. Kinetic analysis yielded a k/sub 1/ of 1.35 x 10/sup 6/ M/sup -1/ x min/sup -1/ and a k..sqrt../sub 1/ of 0.032 min/sup -1/, K/sub d/ = k..sqrt../sub 1//k/sub 1/ = 24 nM. The subcellular localization of the putative TXA/sub 2//PGH/sub 2/ receptor was determined using (/sup 125/I)-PTA-OH binding as a marker for the receptor. (/sup 125/I)-PTA-OH binding as a marker for the receptor. (/sup 125/I)-PTA-OH binding, was coenriched with markers for plasma membranes and dense tubular system; but not with markers for cytoplasmic constituents, mitochondria, or granules.

  19. Prostaglandin potentiates 5-HT responses in stomach and ileum innervating visceral afferent sensory neurons

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sojin; Jin, Zhenhua; Lee, Goeun [Department of Physiology, School of Medicine, Kyung Hee University, Seoul 130-701 (Korea, Republic of); Park, Yong Seek; Park, Cheung-Seog [Department of Microbiology, School of Medicine, Kyung Hee University, Seoul 130-701 (Korea, Republic of); Jin, Young-Ho, E-mail: jinyh@khu.ac.kr [Department of Physiology, School of Medicine, Kyung Hee University, Seoul 130-701 (Korea, Republic of)

    2015-01-02

    Highlights: • Prostaglandin E2 (PGE{sub 2}) effect was tested on visceral afferent neurons. • PGE{sub 2} did not evoke response but potentiated serotonin (5-HT) currents up to 167%. • PGE{sub 2}-induced potentiation was blocked by E-prostanoid type 4 receptors antagonist. • PGE{sub 2} effect on 5-HT response was also blocked by protein kinase A inhibitor KT5720. • Thus, PGE{sub 2} modulate visceral afferent neurons via synergistic signaling with 5-HT. - Abstract: Gastrointestinal disorder is a common symptom induced by diverse pathophysiological conditions that include food tolerance, chemotherapy, and irradiation for therapy. Prostaglandin E{sub 2} (PGE{sub 2}) level increase was often reported during gastrointestinal disorder and prostaglandin synthetase inhibitors has been used for ameliorate the symptoms. Exogenous administration of PGE{sub 2} induces gastrointestinal disorder, however, the mechanism of action is not known. Therefore, we tested PGE{sub 2} effect on visceral afferent sensory neurons of the rat. Interestingly, PGE{sub 2} itself did not evoked any response but enhanced serotonin (5-HT)-evoked currents up to 167% of the control level. The augmented 5-HT responses were completely inhibited by a 5-HT type 3 receptor antagonist, ondansetron. The PGE{sub 2}-induced potentiation were blocked by a selective E-prostanoid type4 (EP{sub 4}) receptors antagonist, L-161,982, but type1 and 2 receptor antagonist AH6809 has no effect. A membrane permeable protein kinase A (PKA) inhibitor, KT5720 also inhibited PGE{sub 2} effects. PGE{sub 2} induced 5-HT current augmentation was observed on 15% and 21% of the stomach and ileum projecting neurons, respectively. Current results suggest a synergistic signaling in visceral afferent neurons underlying gastrointestinal disorder involving PGE{sub 2} potentiation of 5-HT currents. Our findings may open a possibility for screen a new type drugs with lower side effects than currently using steroidal prostaglandin

  20. Effects of zinc acexamate on gastric mucosal production of prostaglandin E2 in normal and stressed rats.

    Science.gov (United States)

    Navarro, C; Escolar, G; Baños, J E; Casanovas, L I; Bulbena, O

    1988-07-01

    Changes in PGE2 levels induced by zinc acexamate (ZAC) at gastricmucosal level were assessed in a rat model. Experiments were performed in normal rats and rats subjected to cold-restraint stress and in experimental conditions in which prostaglandins (PGs) synthesis was inhibited by prior administration of indomethacin. Gastric injuries after different treatments were quantified macro and microscopically. Total amount of PGE2 and mucus material recovered from gastric mucosa were increased after ZAC treatment. Indomethacin aggravated gastric damage secondary to stress and inhibited PGE2 and mucus increase appearing after ZAC treatment. These data confirm the relation between PGE2, mucus production and gastric protection. ZAC 200 mg/kg was able to reduce the gastric damage induced by stress. This decrease was also evident in the group receiving indomethacin before ZAC administration. These experiments indicate that ZAC exhibits its antiulcer action by increasing prostaglandins but other mechanisms independent of PGs synthesis are also involved.

  1. Prostaglandin signaling suppresses beneficial microglial function in Alzheimer's disease models.

    Science.gov (United States)

    Johansson, Jenny U; Woodling, Nathaniel S; Wang, Qian; Panchal, Maharshi; Liang, Xibin; Trueba-Saiz, Angel; Brown, Holden D; Mhatre, Siddhita D; Loui, Taylor; Andreasson, Katrin I

    2015-01-01

    Microglia, the innate immune cells of the CNS, perform critical inflammatory and noninflammatory functions that maintain normal neural function. For example, microglia clear misfolded proteins, elaborate trophic factors, and regulate and terminate toxic inflammation. In Alzheimer's disease (AD), however, beneficial microglial functions become impaired, accelerating synaptic and neuronal loss. Better understanding of the molecular mechanisms that contribute to microglial dysfunction is an important objective for identifying potential strategies to delay progression to AD. The inflammatory cyclooxygenase/prostaglandin E2 (COX/PGE2) pathway has been implicated in preclinical AD development, both in human epidemiology studies and in transgenic rodent models of AD. Here, we evaluated murine models that recapitulate microglial responses to Aβ peptides and determined that microglia-specific deletion of the gene encoding the PGE2 receptor EP2 restores microglial chemotaxis and Aβ clearance, suppresses toxic inflammation, increases cytoprotective insulin-like growth factor 1 (IGF1) signaling, and prevents synaptic injury and memory deficits. Our findings indicate that EP2 signaling suppresses beneficial microglia functions that falter during AD development and suggest that inhibition of the COX/PGE2/EP2 immune pathway has potential as a strategy to restore healthy microglial function and prevent progression to AD.

  2. Prostaglandins temporally regulate cytoplasmic actin bundle formation during Drosophila oogenesis.

    Science.gov (United States)

    Spracklen, Andrew J; Kelpsch, Daniel J; Chen, Xiang; Spracklen, Cassandra N; Tootle, Tina L

    2014-02-01

    Prostaglandins (PGs)--lipid signals produced downstream of cyclooxygenase (COX) enzymes--regulate actin dynamics in cell culture and platelets, but their roles during development are largely unknown. Here we define a new role for Pxt, the Drosophila COX-like enzyme, in regulating the actin cytoskeleton--temporal restriction of actin remodeling during oogenesis. PGs are required for actin filament bundle formation during stage 10B (S10B). In addition, loss of Pxt results in extensive early actin remodeling, including actin filaments and aggregates, within the posterior nurse cells of S9 follicles; wild-type follicles exhibit similar structures at a low frequency. Hu li tai shao (Hts-RC) and Villin (Quail), an actin bundler, localize to all early actin structures, whereas Enabled (Ena), an actin elongation factor, preferentially localizes to those in pxt mutants. Reduced Ena levels strongly suppress early actin remodeling in pxt mutants. Furthermore, loss of Pxt results in reduced Ena localization to the sites of bundle formation during S10B. Together these data lead to a model in which PGs temporally regulate actin remodeling during Drosophila oogenesis by controlling Ena localization/activity, such that in S9, PG signaling inhibits, whereas at S10B, it promotes Ena-dependent actin remodeling.

  3. Prostacyclin analogs suppress the synthesis of tumor necrosis factor-alpha in LPS-stimulated human peripheral blood mononuclear cells

    NARCIS (Netherlands)

    Eisenhut, T; Sinha, B; Gröttrup-Wolfers, E; Semmler, J; Siess, W; Endres, S

    1993-01-01

    Recent reports have shown that prostaglandin E2 (PGE2) is able to suppress lipopolysaccharide (LPS)-stimulated production of tumor necrosis factor-alpha (TNF-alpha). In the present study we compared PGE2 with prostacyclin (PGI2) analogs in their potency to influence LPS-stimulated production of inte

  4. Alpha1 and Alpha2 Integrins Mediate Invasive Activity of Mouse Mammary Carcinoma Cells through Regulation of Stromelysin-1 Expression

    Energy Technology Data Exchange (ETDEWEB)

    Lochter, Andre; Navre, Marc; Werb, Zena; Bissell, Mina J

    1998-06-29

    Tumor cell invasion relies on cell migration and extracellular matrix proteolysis. We investigated the contribution of different integrins to the invasive activity of mouse mammary carcinoma cells. Antibodies against integrin subunits {alpha}6 and {beta}1, but not against {alpha}1 and {alpha}2, inhibited cell locomotion on a reconstituted basement membrane in two-dimensional cell migration assays, whereas antibodies against {beta}1, but not against a6 or {alpha}2, interfered with cell adhesion to basement membrane constituents. Blocking antibodies against {alpha}1 integrins impaired only cell adhesion to type IV collagen. Antibodies against {alpha}1, {alpha}2, {alpha}6, and {beta}1, but not {alpha}5, integrin subunits reduced invasion of a reconstituted basement membrane. Integrins {alpha}1 and {alpha}2, which contributed only marginally to motility and adhesion, regulated proteinase production. Antibodies against {alpha}1 and {alpha}2, but not {alpha}6 and {beta}1, integrin subunits inhibited both transcription and protein expression of the matrix metalloproteinase stromelysin-1. Inhibition of tumor cell invasion by antibodies against {alpha}1 and {alpha}2 was reversed by addition of recombinant stromelysin-1. In contrast, stromelysin-1 could not rescue invasion inhibited by anti-{alpha}6 antibodies. Our data indicate that {alpha}1 and {alpha}2 integrins confer invasive behavior by regulating stromelysin-1 expression, whereas {alpha}6 integrins regulate cell motility. These results provide new insights into the specific functions of integrins during tumor cell invasion.

  5. Prostaglandines per tractar l'asma

    OpenAIRE

    Herrerias, Aida; Departament de Farmacologia, de Terapèutica i de Toxicologia

    2009-01-01

    Aproximadament 150 milions de persones arreu del món pateixen asma, sent a les societats més avançades on la incidència és més elevada. I no s’atura. Dades que s’han de tenir molt presents, donat que actualment manquem d’un fàrmac curatiu. A més, si no és correctament avaluada i tractada, aquesta malaltia pot mermar considerablement la qualitat de vida de les persones afectades. En la recerca de nous camins terapèutics, les prostaglandines (PG) han aparegut a escena. Mol·lècules en origen, co...

  6. Quantitative characterization of prostaglandins in the uterus of early pregnant cattle.

    Science.gov (United States)

    Ulbrich, S E; Schulke, K; Groebner, A E; Reichenbach, H D; Angioni, C; Geisslinger, G; Meyer, H H D

    2009-08-01

    Prostaglandins (PGs) are important regulators of reproductive processes including early embryonic development. We analyzed the most relevant PG in bovine uteri at different preimplantation pregnancy stages when compared with non-pregnant controls. Additionally, endometrium and trophoblast tissues were examined regarding specific enzymes and receptors involved in PG generation and function. Simmental heifers were artificially inseminated or received seminal plasma only. At days 12, 15, or 18, post-estrus uteri were flushed for PG determination by liquid chromatography-tandem mass spectrometry. Endometrium and trophoblast tissues were sampled for RNA extraction and quantitative real-time PCR analysis. At all days and points of time examined, the concentration of 6-keto PGF(1alpha) (stable metabolite of PGI(2)) was predominant followed by PGF(2alpha)>PGE(2)>PGD(2) approximately TXB(2) (stable metabolite of TXA(2)). At days 15 and 18, PG increased from overall low levels at day 12, with a much more pronounced increase during pregnancy. The PGF(2alpha)/PGE(2) ratio was not influenced by status. The highest PG concentration was measured at day 15 with 6-keto PGF(1alpha) (6.4 ng/ml) followed by PGF(2alpha) (1.1 ng/ml) and PGE(2) (0.3 ng/ml). Minor changes in endometrial PG biosynthesis enzymes occurred due to pregnancy. Trophoblasts revealed high transcript abundance of general and specific PG synthases contributing to uterine PG. As PGI(2) and PGF(2alpha) receptors were abundantly expressed by the trophoblast, abundant amounts of PGI(2) and PGF(2alpha) in the uterine lumen point towards an essential role of PG for the developing embryo. High amounts of PG other than PGE(2) in the preimplantation uterus may be essential rather than detrimental for successful reproduction.

  7. Interleukin-2 deficit in hemodialysis patients. Role of prostaglandins.

    Science.gov (United States)

    Glez-Gutiérrez, M; de Francisco, A L; Sanz de Castro, S; Ruiz, J C; Prieto, M; García Fuentes, M; Arias, M

    1992-01-01

    Uremic patients suffer from various immunological alterations, whose pathogenesis is still unknown. Here, we studied 37 hemodialysis patients in order to investigate the role of prostaglandins (PGs) in uremic immunological deficiency, specifically in relation to interleukin-2 (IL-2) synthesis. We confirmed previous published data on deficient response to PHA in chronic renal failure patients (cpm, mean +/- SEM: 15,400 +/- 2,100 in uremics vs. 29,500 +/- 3,380 in controls, p < 0.04) and established a correlation between this deficiency and diminished IL-2 synthesis (r = 0.619, p < 0.05). The direct measurement of PGs in lymphocyte cultures showed greatly increased concentrations in the presence of uremic serum (US). We found that PGs synthesis can be inhibited by up to 80% if cultures are supplemented with indomethacin (IND--a cyclooxigenase inhibitor) or by removal of monocytes (producers of PGs). Both methods situated the uremic proliferative response within the normal range in cultures with FCS, and close to the normal range in cultures with US. We observed a deficit of IL-2 in hemodialysis patients (means +/- SD: 8,940 +/- 6,420 in uremics vs. 16,900 +/- 3,890 in controls). Addition of exogenous IL-2 normalized lymphocyte response even in US cultures, with no additive effect between PGs inhibition and exogenous IL-2 except in US cultures. It is suggested that IL-2 deficit of uremics depends, at least in part, on an increase in PGs synthesis induced by US.(ABSTRACT TRUNCATED AT 250 WORDS)

  8. Prostaglandin release from rat femurs after implantation of hydroxylapatite and aluminium oxide ceramics.

    Science.gov (United States)

    Wittenberg, J M; Wittenberg, R H; Osborn, J F

    1995-12-01

    The bony reaction after implantation of uncemented ceramics is of special interest. Therefore porous and dense hydroxylapatite and aluminium oxide ceramics were implanted in rat femurs. One group received no surgical manipulation and another with a sham procedure where no ceramics were implanted served as controls. After 6 and 10 days the rat femurs were harvested and the release of PGE2 and 6-keto-PGF1 alpha was measured with specific radioimmunoassays. Decrease in the release of PGE2 from day 6 to day 10 was present in all three implants. In contrast, 6-keto-PGF1 alpha increased from day 6 to day 10. Comparing the ceramic types an increase in 6-keto-PGF1 alpha release was seen in the porous hydroxylapatite group. These prostaglandin (PG) release patterns after ceramic implantation are similar to those of fracture healing, but aluminium oxide seems to be inert, while hydroxylapatite, especially the porous type, stimulates 6-keto-PGF1 alpha release.

  9. Gamma-type gliadins cause secretion of prostaglandin E2 in patients with coeliac disease.

    Science.gov (United States)

    Friis, S; Anthonsen, D; Norén, O; Sjöström, H

    1994-12-16

    Coeliac disease is induced by polypeptides in the prolamin fraction of wheat, termed gliadin. It has previously been demonstrated that the alpha-, the beta- and the gamma-gliadin fractions contain toxic components and it has furthermore been strongly indicated that alpha-type gliadins are toxic. Due to insufficient protein separation methods there has been no information as to whether also the gamma-type gliadins are injurious in coeliac disease. We have therefore purified one alpha-type (alpha-39) and two gamma-type gliadins (gamma-36 and gamma-47) in a preparative scale by a combination of different ion exchange chromatographies. The purity was analyzed by high performance liquid chromatography and by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulphate, while the typing was based on determination of N-terminal amino acid sequence. Six patients with coeliac disease in remission were included in the study. Each of the purified gliadins was given by an intestinal perfusion technique to two patients. The perfusion fluid was collected and analyzed for the concentration of prostaglandin E2 (PGE2) as a marker for a toxic effect. All patients reacted with increased PGE2 secretion. For the first time it is clearly demonstrated that gamma-type gliadins are active in coeliac disease.

  10. The role of the active site Zn in the catalytic mechanism of the GH38 Golgi alpha-mannosidase II: Implications from noeuromycin inhibition

    DEFF Research Database (Denmark)

    Bols, Mikael; Kuntz, Douglas A.; Rose, David R.

    2006-01-01

    Golgi alpha-mannosidase II (GMII) is a Family 38 glycosyl hydrolase involved in the eukaryotic N-glycosylation pathway in protein synthesis. Understanding of its catalytic mechanism has been of interest for the development of specific inhibitors that could lead to novel anti-metastatic or anti...

  11. RELEVANCE OF CLASSIC ANTINEUTROPHIL CYTOPLASMIC AUTOANTIBODY (C-ANCA)-MEDIATED INHIBITION OF PROTEINASE 3-ALPHA-1-ANTITRYPSIN COMPLEXATION TO DISEASE-ACTIVITY IN WEGENER-GRANULOMATOSIS

    NARCIS (Netherlands)

    DOLMAN, KM; STEGEMAN, CA; VANDEWIEL, BA; HACK, CE; BORNE, AEGKV; KALLENBERG, CGM; GOLDSCHMEDING, R

    1993-01-01

    In the sera of patients with Wegener's granulomatosis (WG), C-ANCA can be detected that are directed against proteinase 3 (PR3). We have previously observed that C-ANCA interfere with PR3 proteolytic activity and with complexation of PR3 with its major physiologic inhibitor, alpha1-antitrypsin (alph

  12. Effect of Recombinant alpha1-Antitrypsin Fc-Fused (AAT-Fc)Protein on the Inhibition of Inflammatory Cytokine Production and Streptozotocin-Induced Diabetes

    NARCIS (Netherlands)

    Lee, S.; Lee, Y.; Hong, K.; Hong, J.; Bae, S.; Choi, J.; Jhun, H.; Kwak, A.; Kim, E.; Jo, S.; Dinarello, C.A.; Kim, S.

    2013-01-01

    alpha1-Antitrypsin (AAT) is a member of the serine proteinase inhibitor family that impedes the enzymatic activity of serine proteinases, including human neutrophil elastase, cathepsin G and neutrophil proteinase 3. Here, we expressed recombinant AAT by fusing the intact AAT gene to the constant reg

  13. ONO 3403, a synthetic serine protease inhibitor, inhibits lipopolysaccharide-induced tumor necrosis factor-alpha and nitric oxide production and protects mice from lethal endotoxic shock

    NARCIS (Netherlands)

    Tumurkhuu, Gantsetseg; Koide, Naoki; Hiwasa, Takaki; Ookoshi, Motohiro; Dagvadorj, Jargalsaikhan; Noman, Abu Shadat Mohammod; Iftakhar-E-Khuda, Imtiaz; Naiki, Yoshikazu; Komatsu, Takayuki; Yoshida, Tomoaki; Yokochi, Takashi

    2011-01-01

    ONO 3403, a new synthetic serine protease inhibitor, is a derivative of camostat mesilate and has a higher protease-inhibitory activity. The effect of ONO 3403 on lipopolysaccharide (LPS)-induced tumor necrosis factor (TNF)-alpha and nitric oxide (NO) production in RAW 264.7 macrophage-like cells wa

  14. Aqueous Extract of Paris polyphylla (AEPP Inhibits Ovarian Cancer via Suppression of Peroxisome Proliferator-Activated Receptor-Gamma Coactivator (PGC-1alpha

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    Chia-Woei Wang

    2016-06-01

    Full Text Available Chemotherapy, a major approach was used in carcinoma treatment, always involves the development of drug resistance as well as side-effects that affect the quality of patients’ lives. An association between epithelial-mesenchymal transition (EMT and chemotherapy resistance was established recently. We demonstrate in this paper that the aqueous extract of Paris polyphylla (AEPP—a traditional Chinese medicine—can be used in various cancer types for suppression of carcinogenesis. We evaluated the suppressions of EMT and mitochondrial activity by AEPP treatment in a high-glucose (HG induced-human ovarian carcinoma cell line (OVCAR-3 cells. The mitochondrial morphology was investigated using MitoTracker Deep Red FM staining. Our results indicated that AEPP reduced the viability of OVCAR-3 cells considerably through induction of apoptosis. However, this inhibitory potential of AEPP was attenuated by HG induction in OVCAR-3 cells. The levels of estrogen-related receptor (ERR-alpha activator and peroxisome proliferator-activated receptor-gamma coactivator (PGC-1alpha were elevated by HG induction, but were suppressed by AEPP treatment. Down-regulations of cell survival and EMT were oberved in OVCAR-3 cells through suppression of PGC-1alpha by AEPP treatment. These results were confirmed through PGC-1alpha knockdown and overexpression in OVCAR-3 cells. Thus, AEPP can be beneficial for treating ovarian cancer and has potential for development of an integrative cancer therapy against ovarian cancer proliferation, metastasis, and migration.

  15. Salvianolic Acid B inhibits platelet adhesion under conditions of flow by a mechanism involving the collagen receptor alpha 2 beta 1

    NARCIS (Netherlands)

    Wu, Ya Ping; Zhao, Xiao Min; Pan, Shao Dong; Guo, De An; Wei, Ran; Han, Ji Ju; Kainoh, Mie; Xia, Zuo Li; de Groot, Philip G.; Lisman, Ton

    2008-01-01

    Salvianolic acid B (SAB) is a component of Danshen, a herb widely used in Chinese medicine, and was previously shown to exert a number of biological activities including inhibition of platelet function, but the exact mechanisms involved are unclear. SAB dose-dependently inhibited platelet deposition

  16. Acute macular edema following intracorporeal prostaglandin injection for erectile dysfunction

    Directory of Open Access Journals (Sweden)

    Asahi MG

    2015-07-01

    Full Text Available Masumi G Asahi, Calvin Chou, Ron P Gallemore Retina Macula Institute, Torrance, CA, USA Purpose: We aimed to describe the first case of macular edema following intracorporeal injection of alprostadil, a prostaglandin E1. Methods: This was a retrospective case report followed with optical coherence tomography, fundus photos, and fluorescein angiography images. Results: A patient developed bilateral cystoid macular edema following intracorporeal injection of alprostadil, a prostaglandin E1 for treatment of erectile dysfunction. The edema resolved following treatment with nonsteroidal anti-inflammatory drugs (NSAIDs and corticosteroids, with subsequent recovery in visual acuity. Discussion: Systemic prostaglandin administration can cause macular edema and vision loss, indicating that elevated systemic prostaglandin levels may affect visual function. This has potential implications for other systemic disorders and treatments that could affect macular function. Keywords: alprostadil, inflammation

  17. Role of nitric oxide and prostaglandin in the maintenance of cortical and renal medullary blood flow

    Directory of Open Access Journals (Sweden)

    S.I Gomez

    2008-02-01

    Full Text Available This study was undertaken in anesthetized dogs to evaluate the relative participation of prostaglandins (PGs and nitric oxide (NO in the maintenance of total renal blood flow (TRBF, and renal medullary blood flow (RMBF. It was hypothesized that the inhibition of NO should impair cortical and medullary circulation because of the synthesis of this compound in the endothelial cells of these two territories. In contrast, under normal conditions of perfusion pressure PG synthesis is confined to the renal medulla. Hence PG inhibition should predominantly impair the medullary circulation. The initial administration of 25 µM kg-1 min-1 NG-nitro-L-arginine methyl ester produced a significant 26% decrease in TRBF and a concomitant 34% fall in RMBF, while the subsequent inhibition of PGs with 5 mg/kg meclofenamate further reduced TRBF by 33% and RMBF by 89%. In contrast, the initial administration of meclofenamate failed to change TRBF, while decreasing RMBF by 49%. The subsequent blockade of NO decreased TRBF by 35% without further altering RMBF. These results indicate that initial PG synthesis inhibition predominantly alters the medullary circulation, whereas NO inhibition decreases both cortical and medullary flow. This latter change induced by NO renders cortical and RMBF susceptible to a further decrease by PG inhibition. However, the decrease in medullary circulation produced by NO inhibition is not further enhanced by subsequent PG inhibition.

  18. Prostaglandins in Cancer Cell Adhesion, Migration, and Invasion

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    David G. Menter

    2012-01-01

    Full Text Available Prostaglandins exert a profound influence over the adhesive, migratory, and invasive behavior of cells during the development and progression of cancer. Cyclooxygenase-2 (COX-2 and microsomal prostaglandin E2 synthase-1 (mPGES-1 are upregulated in inflammation and cancer. This results in the production of prostaglandin E2 (PGE2, which binds to and activates G-protein-coupled prostaglandin E1-4 receptors (EP1-4. Selectively targeting the COX-2/mPGES-1/PGE2/EP1-4 axis of the prostaglandin pathway can reduce the adhesion, migration, invasion, and angiogenesis. Once stimulated by prostaglandins, cadherin adhesive connections between epithelial or endothelial cells are lost. This enables cells to invade through the underlying basement membrane and extracellular matrix (ECM. Interactions with the ECM are mediated by cell surface integrins by “outside-in signaling” through Src and focal adhesion kinase (FAK and/or “inside-out signaling” through talins and kindlins. Combining the use of COX-2/mPGES-1/PGE2/EP1-4 axis-targeted molecules with those targeting cell surface adhesion receptors or their downstream signaling molecules may enhance cancer therapy.

  19. [The antagonistic effect of aspirin on the expression of prostaglandin participation in the antihypertensive activity of ACE inhibitors].

    Science.gov (United States)

    Alimento, M; Campodonico, J; Santambrogio, G; Rossi, M; Trabattoni, D; Celeste, F; Guazzi, M

    1997-06-01

    ACE-inhibitors antagonize both angiotensin production and bradykinin breakdown, resulting in enhancement of vasodilating prostaglandin release. This provides an explanation for the experimental observation that cycloxygenase blockers (such as aspirin or indomethacin) may counteract the antihypertensive efficacy of the ACE-inhibitors; it may be also possible that hypertensive patients taking aspirin as an antiplatelet agent may fail to benefit from ACE-inhibition. This study was aimed at: evaluating the magnitude and incidence of the inhibitory phenomenon; defining the minimal aspirin dosage that produces an antagonistic effect, as well as the possible reasons for a different individual susceptibility. We have studied untreated patients with mild (10 cases, Group 1), moderate (16 cases, Group 2) or severe (26 cases, Group 3) hypertension. The ACE-inhibitor enalapril was used at doses of 10 mg bid (groups 1 and 2) or 20 mg bid (Group 3). Active drug treatment periods had a 5-day duration. A daily dose of aspirin of 100 mg had no effect on the antihypertensive efficacy of enalapril. On the contrary, when a dose of 300 mg was used, 60, 57 and 50% of patients in Group 1, 2 and 3, respectively, showed a > 20% restraint of the mean arterial pressure fall with enalapril (20% was the lower arbitrary limit for defining antagonism). Inhibition was independent of the sequence of drug administration. In these patients counteraction averaged 60, 70 and 90%, respectively. In them, and not in the remaining patients in each group, aspirin substantially attenuated the renin rise elicited by ACE-inhibition. These data suggest that: a dosage of 100 mg aspirin is devoid of any inhibitory effect; more that 50% of ACE inhibited patients are, at least in the short term, susceptible to the action of 300 mg aspirin, regardless of the severity of hypertension; counteraction is seemingly mediated through a prostaglandin inhibition and depends on the individual predominance of prostaglandin

  20. Rescue of amyloid-Beta-induced inhibition of nicotinic acetylcholine receptors by a peptide homologous to the nicotine binding domain of the alpha 7 subtype.

    Directory of Open Access Journals (Sweden)

    Arthur A Nery

    Full Text Available Alzheimer's disease (AD is characterized by brain accumulation of the neurotoxic amyloid-β peptide (Aβ and by loss of cholinergic neurons and nicotinic acetylcholine receptors (nAChRs. Recent evidence indicates that memory loss and cognitive decline in AD correlate better with the amount of soluble Aβ than with the extent of amyloid plaque deposits in affected brains. Inhibition of nAChRs by soluble Aβ40 is suggested to contribute to early cholinergic dysfunction in AD. Using phage display screening, we have previously identified a heptapeptide, termed IQ, homologous to most nAChR subtypes, binding with nanomolar affinity to soluble Aβ40 and blocking Aβ-induced inhibition of carbamylcholine-induced currents in PC12 cells expressing α7 nAChRs. Using alanine scanning mutagenesis and whole-cell current recording, we have now defined the amino acids in IQ essential for reversal of Aβ40 inhibition of carbamylcholine-induced responses in PC12 cells, mediated by α7 subtypes and other endogenously expressed nAChRs. We further investigated the effects of soluble Aβ, IQ and analogues of IQ on α3β4 nAChRs recombinantly expressed in HEK293 cells. Results show that nanomolar concentrations of soluble Aβ40 potently inhibit the function of α3β4 nAChRs, and that subsequent addition of IQ or its analogues does not reverse this effect. However, co-application of IQ makes the inhibition of α3β4 nAChRs by Aβ40 reversible. These findings indicate that Aβ40 inhibits different subtypes of nAChRs by interacting with specific receptor domains homologous to the IQ peptide, suggesting that IQ may be a lead for novel drugs to block the inhibition of cholinergic function in AD.

  1. Immunolocalization of a microsomal prostaglandin E synthase in rabbit kidney.

    Science.gov (United States)

    Fuson, Amanda L; Komlosi, Peter; Unlap, Tino M; Bell, P Darwin; Peti-Peterdi, János

    2003-09-01

    PGE2, the major cyclooxygenase (COX) metabolite of arachidonic acid, is an important paracrine regulator of numerous tubular and vascular functions in the kidney. To date, COX activity has been considered the key step in prostaglandin synthesis and is well characterized. However, much less is known about the recently cloned microsomal PGE2 synthase (mPGES), the terminal enzyme of PGE2 synthesis, which converts COX-derived PGH2 to the biologically important PGE2. Present studies provide the detailed localization of mPGES protein in the rabbit kidney using immunohistochemistry. In the cortex, strong mPGES labeling was found in the macula densa (MD) and principal cells of the connecting segment and cortical collecting tubule but not in intercalated cells. The medulla was abundant in mPGES-positive structures, with heavy labeling in the collecting duct system. In descending thin limbs and renal medullary interstitial cells, mPGES expression was less intense, and it was below the limits of detection in the vasa recta. Expression of MD mPGES, similarly to COX-2, was greatly increased in response to low-salt diet and angiotensin I-converting enzyme inhibition by captopril. These findings suggest autocrine regulation of renal salt and water transport by PGE2 in descending thin limb and collecting tubule and a paracrine effect of PGE2 on the glomerular and medullary vasculature. Similar to other organs, mPGES in the kidney is an inducible enzyme and may be similarly regulated and acts in concert with COX-2.

  2. Presynaptic. cap alpha. -adrenoceptors and opiate receptors: inhibition of (/sup 3/H)noradrenaline release from rat cerebral cortex slices by different mechanisms

    Energy Technology Data Exchange (ETDEWEB)

    Schoffelmeer, A.N.M.; Mulder, A.H. (Vrije Univ., Amsterdam (Netherlands))

    1982-04-23

    The inhibitory effects of morphine and Cd/sup 2 +/ on electrically evoked (/sup 3/H)noradrenaline release from superfused brain slices were unaffected when release was enhanced by increasing the pulse duration, while the inhibitory effect of noradrenaline and the enhancing effect of phentolamine were diminished. A similar enhancement of (/sup 3/H)noradrenaline release by 4-aminopyridine reduced the modulatory effects of all drugs examined. Therefore there seem to be different mechanisms for the effect of presynaptic ..cap alpha..-adrenoceptors and opiate receptors on the availability of Ca/sup 2 +/ for the stimulus-secretion coupling process in noradrenergic nerve terminals.

  3. SA13353 (1-[2-(1-Adamantyl)ethyl]-1-pentyl-3-[3-(4-pyridyl)propyl]urea) inhibits TNF-alpha production through the activation of capsaicin-sensitive afferent neurons mediated via transient receptor potential vanilloid 1 in vivo.

    Science.gov (United States)

    Murai, Masaaki; Tsuji, Fumio; Nose, Masafumi; Seki, Iwao; Oki, Kenji; Setoguchi, Chikako; Suhara, Hiroshi; Sasano, Minoru; Aono, Hiroyuki

    2008-07-07

    Tumor necrosis factor-alpha (TNF-alpha) is known to play a crucial role in the pathogenesis of rheumatoid arthritis. In the present study, we demonstrate the effects of SA13353 (1-[2-(1-Adamantyl)ethyl]-1-pentyl-3-[3-(4-pyridyl)propyl]urea), a novel orally active inhibitor of TNF-alpha production, in animal models, and its mechanism of action on TNF-alpha production. SA13353 significantly inhibited lipopolysaccharide (LPS)-induced TNF-alpha production in a dose-dependent manner in rats. Moreover, SA13353 exhibited a binding affinity for the rat vanilloid receptor and increased neuropeptide release from the rat dorsal root ganglion neurons. However, its effects were blocked by pretreatment with the transient receptor potential vanilloid 1 (TRPV1) antagonist capsazepine. The ability of SA13353 and capsaicin to inhibit LPS-induced TNF-alpha production was eliminated by sensory denervation or capsazepine pretreatment in vivo. Although they inhibited LPS-induced TNF-alpha production in mice, these effects were not observed in TRPV1 knockout mice. SA13353 provoked the release of neuropeptides without nerve inactivation, even when chronically administered to rats. These results suggest that SA13353 inhibits TNF-alpha production through activation of capsaicin-sensitive afferent neurons mediated via TRPV1 in vivo. Post-onset treatment of SA13353 strongly reduced the hindpaw swelling and joint destruction associated with collagen-induced arthritis in rats. Thus, SA13353 is expected to be a novel anti-arthritic agent with a unique mechanism of action.

  4. Spironolactone inhibits production of proinflammatory cytokines, including tumour necrosis factor-alpha and interferon-gamma, and has potential in the treatment of arthritis

    DEFF Research Database (Denmark)

    Bendtzen, K; Hansen, P R; Rieneck, K

    2003-01-01

    for up to 22 months with 1-3 mg/kg/day. Spironolactone, at in vivo attainable doses, markedly suppressed transcription of several proinflammatory cytokines and, accordingly, inhibited release of tumour necrosis factor, lymphotoxin, interferon-gamma, granulocyte-macrophage colony-stimulating factor....... In conclusion, spironolactone inhibits production of several proinflammatory cytokines considered to be of pathogenic importance in many immunoinflammatory diseases and shows positive effect in patients with chronic arthritis. Its effect as an anti-inflammatory drug should be explored, because prolonged...... and interleukin 6 (70-90% inhibition). Release of these cytokines was also suppressed when testing whole blood from RA patients receiving 50 mg spironolactone twice daily, indicating that pharmaceutical use of the drug may suppress the release of inflammatory cytokines. Spironolactone therapy was generally well...

  5. Effect of ozone exposure on lung functions and plasma prostaglandin and thromboxane concentrations in guinea pigs

    Energy Technology Data Exchange (ETDEWEB)

    Miller, P.D.; Ainsworth, D.; Lam, H.F.; Amdur, M.O.

    1987-03-30

    Male Hartley guinea pigs were exposed either to filtered air or to 1 ppm ozone (O/sub 3/) for 1 hr. At 2, 8, 24, or 48 hr after exposure we measured ventilation, respiratory mechanics, lung volumes, diffusing capacity for carbon monoxide (DLCO), and alveolar volume (VA) in anesthetized, tracheotomized animals. Respiratory frequency and tidal volume were unchanged in all groups. Pulmonary resistance was increased 2 hr after O/sub 3/ but returned to control at 8 hr and thereafter. Prolonged reductions in lung volumes (total lung capacity, vital capacity, functional residual capacity, and residual volume) as well as in DLCO and VA occurred after O/sub 3/, with maximum decreases at 8 and 24 hr postexposure. Increased ratios of wet lung weight to body weight were seen at 2, 8, and 24 hr. In separate groups of animals, also exposed either to filtered air or to 1 ppm O/sub 3/, plasma eicosanoid (EC) concentrations were measured at 2, 8, 24, 48, or 72 hr after exposure. Significant increases in thromboxane B2 concentrations were seen at 2, 24, and 48 hr after exposure. Plasma concentrations of 6-keto prostaglandin F1 alpha (PGF1 alpha) and prostaglandin E1 (PGE1) were increased at 24 hr and at 24, 48, and 72 hr, respectively. The nature of this long-term pulmonary response to a short-term exposure to O/sub 3/ suggests alveolar involvement, including probable alveolar duct constriction and localized pulmonary edema. Although changes in plasma EC concentrations were observed concurrent with impaired lung functions, no simple causal relationship was apparent from these studies.

  6. Prostaglandins in the perilymph of guinea pig with type II collagen induced ear diseases

    Energy Technology Data Exchange (ETDEWEB)

    Takeda, T.; Chiang, T.; Kitano, H.; Sudo, N.; Kim, S.Y.; Ha, S.; Woo, V.; Wolf, B.; Floyd, R.; Yoo, T.J.

    1986-03-01

    The authors have studied the prostaglandins (PGs) in the perilymph from guinea pig with type II collagen induced autoimmune ear disease. Hartly guinea pigs were immunized with type II collagen in CFA and auditory brain stem responses (ABR) were measured at 2, 3, 4, and 6 months after initial immunization perilymph was obtained and the levels of PGE2 and 6 keto-PGFl..cap alpha.. were measured by radioimmunoassays. Temporal bones were examined for the histopathologic changes. Immunized guinea pigs showed the evidence of hearing loss by ABR. The temporal bones showed the following changes: spiral ganglia degeneration, mild to moderate degree of degeneration in organ of Corti, infrequent very mild endolymphatic hydrops and labrynthitis. The perilymph from immunized animals contained about 5 times more PGE2 and about 3 times more 6 keto-PGFl..cap alpha.. than control animals. However, between these two groups, there was no difference in the CSF and sera levels of PGE2 and 6 keto-PGFl..cap alpha... Thus, this study suggests that these inflammatory mediators might be involved in the pathogenesis of collagen induced autoimmune inner ear disease.

  7. Phytoestrogens modulate prostaglandin production in bovine endometrium: cell type specificity and intracellular mechanisms.

    Science.gov (United States)

    Woclawek-Potocka, Izabela; Acosta, Tomas J; Korzekwa, Anna; Bah, Mamadou M; Shibaya, Masami; Okuda, Kiyoshi; Skarzynski, Dariusz J

    2005-05-01

    Prostaglandins (PGs) are known to modulate the proper cyclicity of bovine reproductive organs. The main luteolytic agent in ruminants is PGF2alpha, whereas PGE2 has luteotropic actions. Estradiol 17beta (E2) regulates uterus function by influencing PG synthesis. Phytoestrogens structurally resemble E2 and possess estrogenic activity; therefore, they may mimic the effects of E2 on PG synthesis and influence the reproductive system. Using a cell-culture system of bovine epithelial and stromal cells, we determined cell-specific effects of phytoestrogens (i.e., daidzein, genistein), their metabolites (i.e., equol and para-ethyl-phenol, respectively), and E2 on PGF2alpha and PGE2 synthesis and examined the intracellular mechanisms of their actions. Both PGs produced by stromal and epithelial cells were significantly stimulated by phytoestrogens and their metabolites. However, PGF2alpha synthesis by both kinds of cells was greater stimulated than PGE2 synthesis. Moreover, epithelial cells treated with phytoestrogens synthesized more PGF2alpha than stromal cells, increasing the PGF2alpha to PGE2 ratio. The epithelial and stromal cells were preincubated with an estrogen-receptor (ER) antagonist (i.e., ICI), a translation inhibitor (i.e., actinomycin D), a protein kinase A inhibitor (i.e., staurosporin), and a phospholipase C inhibitor (i.e., U73122) for 0.5 hrs and then stimulated with equol, para-ethyl-phenol, or E2. Although the action of E2 on PGF2alpha synthesis was blocked by all reagents, the stimulatory effect of phytoestrogens was blocked only by ICI and actinomycin D in both cell types. Moreover, in contrast to E2 action, phytoestrogens did not cause intracellular calcium mobilization in either epithelial or stromal cells. Phytoestrogens stimulate both PGF2alpha and PGE2 in both cell types of bovine endometrium via an ER-dependent genomic pathway. However, because phytoestrogens preferentially stimulated PGF2alpha synthesis in epithelial cells of bovine

  8. Lipopolysaccharide (LPS) and tumor necrosis factor alpha (TNFα) blunt the response of Neuropeptide Y/Agouti-related peptide (NPY/AgRP) glucose inhibited (GI) neurons to decreased glucose.

    Science.gov (United States)

    Hao, Lihong; Sheng, Zhenyu; Potian, Joseph; Deak, Adam; Rohowsky-Kochan, Christine; Routh, Vanessa H

    2016-10-01

    A population of Neuropeptide Y (NPY) neurons which co-express Agouti-related peptide (AgRP) in the arcuate nucleus of the hypothalamus (ARC) are inhibited at physiological levels of brain glucose and activated when glucose levels decline (e.g. glucose-inhibited or GI neurons). Fasting enhances the activation of NPY/AgRP-GI neurons by low glucose. In the present study we tested the hypothesis that lipopolysaccharide (LPS) inhibits the enhanced activation of NPY/AgRP-GI neurons by low glucose following a fast. Mice which express green fluorescent protein (GFP) on their NPY promoter were used to identify NPY/AgRP neurons. Fasting for 24h and LPS injection decreased blood glucose levels. As we have found previously, fasting increased c-fos expression in NPY/AgRP neurons and increased the activation of NPY/AgRP-GI neurons by decreased glucose. As we predicted, LPS blunted these effects of fasting at the 24h time point. Moreover, the inflammatory cytokine tumor necrosis factor alpha (TNFα) blocked the activation of NPY/AgRP-GI neurons by decreased glucose. These data suggest that LPS and TNFα may alter glucose and energy homeostasis, in part, due to changes in the glucose sensitivity of NPY/AgRP neurons. Interestingly, our findings also suggest that NPY/AgRP-GI neurons use a distinct mechanism to sense changes in extracellular glucose as compared to our previous studies of GI neurons in the adjacent ventromedial hypothalamic nucleus.

  9. Ionic radiocontrast inhibits endothelium-dependent vasodilation of the canine renal artery in vitro: possible mechanism of renal failure following contrast medium infusion

    Directory of Open Access Journals (Sweden)

    B. Discigil

    2004-02-01

    Full Text Available To determine if radiocontrast impairs vascular relaxation of the renal artery, segments (4-5 mm in length of canine renal artery were suspended in vitro in organ chambers to measure isometric force (95% O2/5% CO2, at 37ºC. Arterial segments with and without endothelium were placed at the optimal point of their length-tension relation and incubated with 10 µM indomethacin to prevent synthesis of endogenous prostanoids. The presence of nonionic radiocontrast (iohexol, Omnipaque 350, 1 ml in 25 ml control solution, 4% (v/v did not alter endothelium-dependent relaxation to acetylcholine in rings precontracted with both norepinephrine and prostaglandin F2alpha (N = 6. When the rings were precontracted with prostaglandin F2alpha, the presence of ionic contrast did not inhibit the relaxation of the arteries. However, in canine renal arteries contracted with norepinephrine, the presence of ionic radiocontrast (diatrizoate meglumine and diatrizoate sodium, MD-76, 1 ml in 25 ml control solution, 4% (v/v inhibited relaxation in response to acetylcholine, sodium nitroprusside (N = 6 in each group, and isoproterenol (N = 5; P < 0.05. Rings were relaxed less than 50% of norepinephrine contraction. Following removal of the contrast, vascular relaxation in response to the agonists returned to normal. These results indicate that ionic radiocontrast nonspecifically inhibits vasodilation (both cAMP-mediated and cGMP-mediated of canine renal arteries contracted with norepinephrine. This reversible impairment of vasodilation could inhibit normal renal perfusion and act as a mechanism of renal failure following radiocontrast infusion. In the adopted experimental protocol the isoproterenol-induced relaxation of renal arteries precontracted with norepinephrine was more affected, suggesting a pivotal role of the cAMP system.

  10. Regulation of prostaglandin metabolism by calcitriol attenuates growth stimulation in prostate cancer cells.

    Science.gov (United States)

    Moreno, Jacqueline; Krishnan, Aruna V; Swami, Srilatha; Nonn, Larisa; Peehl, Donna M; Feldman, David

    2005-09-01

    Calcitriol exhibits antiproliferative and pro-differentiation effects in prostate cancer. Our goal is to further define the mechanisms underlying these actions. We studied established human prostate cancer cell lines and primary prostatic epithelial cells and showed that calcitriol regulated the expression of genes involved in the metabolism of prostaglandins (PGs), known stimulators of prostate cell growth. Calcitriol significantly repressed the mRNA and protein expression of prostaglandin endoperoxide synthase/cyclooxygenase-2 (COX-2), the key PG synthesis enzyme. Calcitriol also up-regulated the expression of 15-hydroxyprostaglandin dehydrogenase, the enzyme initiating PG catabolism. This dual action was associated with decreased prostaglandin E2 secretion into the conditioned media of prostate cancer cells exposed to calcitriol. Calcitriol also repressed the mRNA expression of the PG receptors EP2 and FP, providing a potential additional mechanism of suppression of the biological activity of PGs. Calcitriol treatment attenuated PG-mediated functional responses, including the stimulation of prostate cancer cell growth. The combination of calcitriol with nonsteroidal anti-inflammatory drugs (NSAIDs) synergistically acted to achieve significant prostate cancer cell growth inhibition at approximately 2 to 10 times lower concentrations of the drugs than when used alone. In conclusion, the regulation of PG metabolism and biological actions constitutes a novel pathway of calcitriol action that may contribute to its antiproliferative effects in prostate cells. We propose that a combination of calcitriol and nonselective NSAIDs might be a useful chemopreventive and/or therapeutic strategy in men with prostate cancer, as it would allow the use of lower concentrations of both drugs, thereby reducing their toxic side effects.

  11. TNF alpha inhibits myogenic differentiation of C2C12 cells through NF-κB activation and impairment of IGF-1 signaling pathway.

    Science.gov (United States)

    Zhao, Q; Yang, S T; Wang, J J; Zhou, J; Xing, S S; Shen, C C; Wang, X X; Yue, Y X; Song, J; Chen, M; Wei, Y Y; Zhou, Q P; Dai, T; Song, Y H

    2015-03-20

    Cachexia or muscle wasting is a common condition that occurs in many chronic diseases. The wasting conditions are characterized by increased levels of TNF-α which was also known as cachectin in the past. But how TNF-α exerts its cachetic effects remains controversial. To clarify this issue, we investigated the impact of TNF-α on C2C12 cell myogenic differentiation. Our results demonstrate that myotube formation was completely inhibited by TNF-α when added to differentiating C2C12 myoblasts. The inhibitory effect of TNF-α on differentiation was accompanied by activation of NF-κB and down regulation of myogenin and Akt. Importantly, TNF-α's effect on differentiation was abolished when IGF-1 was added to the culture. IGF-1 treatment also inhibited NF-κB reporter activity and restored Akt levels. Our data suggest that TNF-α inhibits myogenic differentiation through NF-κB activation and impairment of IGF-1 signaling pathway. The reversal of TNF-α induced inhibition of myogenesis by IGF-1 may have significant therapeutic potential.

  12. Prostaglandins and their receptors in insect biology

    Directory of Open Access Journals (Sweden)

    David eStanley

    2011-12-01

    Full Text Available We treat the biological significance of prostaglandins (PGs and their known receptors in insect biology. PGs and related eicosanoids are oxygenated derivatives of arachidonic acid (AA and two other C20 polyunsaturated fatty acids. PGs are mostly appreciated in the context of biomedicine, but a growing body of literature indicates the biological significance of these compounds extends throughout the animal kingdom, and possibly beyond. PGs act in several crucial areas of insect biology. In reproduction, a specific PG, PGE2, releases oviposition behavior in most crickets and a few other insect species; PGs also mediate events in egg development in some species, which may represent all insects. PGs play major roles in modulating fluid secretion in Malpighian tubules, rectum and salivary glands, although, again, this has been studied in only a few insect species that may represent the Class. Insect immunity is a very complex defense system. PGs and other eicosanoids mediate a large number of immune reactions to infection and invasion. The actions of most PGs are mediated by specific receptors. Biomedical research has discovered a great deal of knowledge about PG receptors in mammals, including their structures, pharmacology, molecular biology and cellular locations. Studies of PG receptors in insects lag behind the biomedical background, however, recent results hold the promise of accelerated research in this area. A PG receptor has been identified in a class of lepidopteran hemocytes and experimentally linked to the release of prophenoloxidase. We conclude that research into PGs and their receptors in insects will lead to important advances in our understanding of insect biology.

  13. PGF2alpha induced differential expression of genes involved in turnover of extracellular matrix in rat decidual cells

    Directory of Open Access Journals (Sweden)

    Callegari Eduardo A

    2005-01-01

    Full Text Available Abstract In the rat, the decidual tissue is an important component for maternal recognition of pregnancy. Decidualization can be induced by either the implantation of the blastocyst or by artificial stimuli. The process of decidua formation or decidualization, is characterized by growth and differentiation of endometrial stromal cells. Prostaglandin F2alpha (PGF2α has been shown to be involved in inhibition of implantation, alteration of embryo development, induction of luteal regression, and the mediation of pregnancy loss induced by microorganism infections. In order to establish a direct role for PGF2α in decidual function, we have evaluated its effects on the expression of an extensive array of genes using primary decidual cell culture. Upon treatment with PGF2α sixty genes were significantly down-regulated whereas only six genes were up-regulated (from a total of 1176 genes studied. Interestingly, the majority of the genes inhibited by PGF2α are either directly or indirectly involved in the turnover of the extracellular matrix (ECM. Genes such as gelatinase A (MMP2, cathepsin L, tissue inhibitor metalloproteinases 2 (TIMP2 and 3 (TIMP3, plasminogen activator inhibitor1 (PAI1, tissue type plasminogen activator (tPA, urokinase plasminogen activator (tPA, endothelin 1, calponin, carboxypeptidase D and calponin acidic were down regulated. The opposite effect was observed for prostromelysin 53 kDa (proMMP3, plasma proteinase I alpha and alpha 1 antiproteinase, all of which were significantly up-regulated by PGF2α. The results strongly suggest that the abortificient role of elevated levels of PGF2α after implantation is due, in large part, to inhibition of genes involved in the normal turnover of the extracellular matrix necessary for decidual formation.

  14. Alpha fetoprotein

    Science.gov (United States)

    Fetal alpha globulin; AFP ... Greater than normal levels of AFP may be due to: Cancer in testes , ovaries, biliary (liver secretion) tract, stomach, or pancreas Cirrhosis of the liver Liver cancer ...

  15. Involvement of serotoninergic 5-HT1A/2A, alpha-adrenergic and dopaminergic D1 receptors in St. John's wort-induced prepulse inhibition deficit: a possible role of hyperforin.

    Science.gov (United States)

    Tadros, Mariane G; Mohamed, Mohamed R; Youssef, Amal M; Sabry, Gilane M; Sabry, Nagwa A; Khalifa, Amani E

    2009-05-16

    Prepulse inhibition (PPI) of acoustic startle response is a valuable paradigm for sensorimotor gating processes. Previous research showed that acute administration of St. John's wort extract (500 mg/kg, p.o.) to rats caused significant disruption of PPI while elevating monoamines levels in some brain areas. The cause-effect relationship between extract-induced PPI disruption and augmented monoaminergic transmission was studied using different serotoninergic, adrenergic and dopaminergic antagonists. The effects of hypericin and hyperforin, as the main active constituents of the extract, on PPI response were also tested. PPI disruption was prevented after blocking the serotoninergic 5-HT1A and 5-HT2A, alpha-adrenergic and dopaminergic D1 receptors. Results also demonstrated a significant PPI deficit after acute treatment of rats with hyperforin, and not hypericin. In some conditions manifesting disrupted PPI response, apoptosis coexists. Electrophoresis of DNA isolated from brains of hyperforin-treated animals revealed absence of any abnormal DNA fragmentation patterns. It is concluded that serotoninergic 5-HT1A and 5-HT2A, alpha-adrenergic and dopaminergic D1 receptors are involved in the disruptive effect of St. John's wort extract on PPI response in rats. We can also conclude that hyperforin, and not hypericin, is one of the active ingredients responsible for St. John's wort-induced PPI disruption with no relation to apoptotic processes.

  16. 24R,25-dihydroxyvitamin D3 [24R,25(OH)2D3] controls growth plate development by inhibiting apoptosis in the reserve zone and stimulating response to 1alpha,25(OH)2D3 in hypertrophic cells.

    Science.gov (United States)

    Boyan, B D; Hurst-Kennedy, J; Denison, T A; Schwartz, Z

    2010-07-01

    Previously we showed that costochondral growth plate resting zone (RC) chondrocytes response primarily to 24R,25(OH)2D3 whereas prehypertrophic and hypertrophic (GC) cells respond to 1alpha,25(OH)2D3. 24R,25(OH)2D3 increases RC cell proliferation and inhibits activity of matrix processing enzymes, suggesting it stabilizes cells in the reserve zone, possibly by inhibiting the matrix degradation characteristic of apoptotic hypertrophic GC cells. To test this, apoptosis was induced in rat RC cells by treatment with exogenous inorganic phosphate (Pi). 24R,25(OH)2D3 blocked apoptotic effects in a dose-dependent manner. Similarly, apoptosis was induced in ATDC5 cell cultures and 24R,25(OH)2D3 blocked this effect. Further studies indicated that 24R,25(OH)2D3 acts via at least two independent pathways. 24R,25(OH)2D3 increases LPA receptor-1 (LPA R1) expression and production of lysophosphatidic acid (LPA), and subsequent LPA R1/3-dependent signaling, thereby decreasing p53 abundance. LPA also increases the Bcl-2/Bax ratio. In addition, 24R,25(OH)2D3 acts by increasing PKC activity. 24R,25(OH)2D3 stimulates 1-hydroxylase activity, resulting in increased levels of 1,25(OH)2D3, and it increases levels of phospholipase A2 activating protein, which is required for rapid 1alpha,25(OH)2D3-dependent activation of PKC in GC cells. These results suggest that 24R,25(OH)2D3 modulates growth plate development by controlling the rate and extent of RC chondrocyte transition to a GC chondrocyte phenotype.

  17. Prostaglandin E2 release from dermis regulates sodium permeability of frog skin epithelium

    DEFF Research Database (Denmark)

    Rytved, Klaus A.; Brodin, Birger; Nielsen, Robert

    1995-01-01

    Arachidonic acid, cAMP, epithelium, frog skin, intracellular calcium, prostaglandin E*U2, sodium transport, tight epithelium.......Arachidonic acid, cAMP, epithelium, frog skin, intracellular calcium, prostaglandin E*U2, sodium transport, tight epithelium....

  18. 芹菜素对鼠肠α-葡萄糖苷酶的抑制活性研究%Apigenin inhibition on alpha glucosidase in mice intestinal

    Institute of Scientific and Technical Information of China (English)

    刘春颖; 蒋淼; 屠洁; 刘冠卉

    2013-01-01

    目的:明确芹菜素对鼠肠α-葡萄糖苷酶的抑制活性.方法:建立体外α-葡萄糖苷酶抑制模型,测定芹菜素对α-葡萄糖苷酶、麦芽糖酶和蔗糖酶的抑制活性.进一步利用Lineweaver-Burk作图法,测定芹菜素对麦芽糖酶和蔗糖酶的抑制类型以及抑制常数.采用离体鼠肠进行体外模拟实验,考察芹菜素对麦芽糖酶和蔗糖酶抑制作用的稳定性.实验结果显示,芹菜素对鼠肠α-葡萄糖苷酶具有较好的抑制活性,半抑制浓度为14.475 μg/mL.芹菜素对鼠肠麦芽糖酶和蔗糖酶的半抑制浓度分别为165.35μg/mL和149.57 μg/mL,抑制类型均为竞争性抑制,抑制常数分别为32.14μg/mL和40μg/mL.在60min内,芹菜素对离体鼠肠体系中蔗糖酶和麦芽糖酶的抑制作用稳定.结论:芹菜素可竞争性抑制鼠肠麦芽糖酶和蔗糖酶的活性,可用于降低糖尿病患者的餐后血糖.%Objective:To evaluate the inhibition activities of apigenin (AP) on mice intestinal α-glucosidase.Methods:In vitro α-glucosidase inhibitory model was established to determine the inhibition activities on α-glucosidase,maltose and sucrose by AP.Furthermore,Lineweaver-Burk mapping method was adopted to determine the type of inhibition of AP.,andThe isolated mice intestine in vitro experiment was used to understand the stability of inhibition on maltose and sucrose.Results:The IC50 of AP on α-glucosidase,maltose and sucrose were 14.475μg/mL,165.35μg/mL and 149.57μg/mL,respectively.Maltose and sucrose were inhibited by AP via reversible competitiveness,and the constant of inhibition (Ki) were 32.14μg/mL and 40μg/mL,respectively.In the isolated mice intestinal system,the inhibition of AP were steady-going during 60min.Conclusions:AP can competitively inhibit mice intestinal maltase and sucrose in mice intestinal.,tTherefore,it Can bemay be used to reduce the postprandial blood glucose in diabetes patients with diabetes mellitus.

  19. Spironolactone inhibits production of proinflammatory cytokines, including tumour necrosis factor-alpha and interferon-gamma, and has potential in the treatment of arthritis

    DEFF Research Database (Denmark)

    Bendtzen, K; Hansen, P R; Rieneck, K

    2003-01-01

    ,000 genes) and enzyme immunoassay for quantitating secreted pro- and anti-inflammatory cytokines. Furthermore, to evaluate the safety and efficacy of spironolactone as an anti-inflammatory drug 21 patients with rheumatoid arthritis (RA), juvenile idiopathic arthritis (JIA) or other arthritides were treated...... for up to 22 months with 1-3 mg/kg/day. Spironolactone, at in vivo attainable doses, markedly suppressed transcription of several proinflammatory cytokines and, accordingly, inhibited release of tumour necrosis factor, lymphotoxin, interferon-gamma, granulocyte-macrophage colony-stimulating factor...... and interleukin 6 (70-90% inhibition). Release of these cytokines was also suppressed when testing whole blood from RA patients receiving 50 mg spironolactone twice daily, indicating that pharmaceutical use of the drug may suppress the release of inflammatory cytokines. Spironolactone therapy was generally well...

  20. Discrepancy between strong cephalic arterial dilatation and mild headache caused by prostaglandin D₂ (PGD₂)

    DEFF Research Database (Denmark)

    Wienecke, Troels; Olesen, Jes; Ashina, Messoud

    2011-01-01

    Prostaglandins (PGs) are involved in nociception and mast cell degranulation. Prostaglandin D₂ (PGD₂) is a vasodilatator released during mast cell degranulation. The headache-eliciting effect of PGD₂ has not been studied in man.......Prostaglandins (PGs) are involved in nociception and mast cell degranulation. Prostaglandin D₂ (PGD₂) is a vasodilatator released during mast cell degranulation. The headache-eliciting effect of PGD₂ has not been studied in man....

  1. Prostaglandin E2-induced colonic secretion in patients with and without colorectal neoplasia

    Directory of Open Access Journals (Sweden)

    Poulsen Steen S

    2010-01-01

    Full Text Available Abstract Background The pathogenesis for colorectal cancer remains unresolved. A growing body of evidence suggests a direct correlation between cyclooxygenase enzyme expression, prostaglandin E2 metabolism and neoplastic development. Thus further understanding of the regulation of epithelial functions by prostaglandin E2 is needed. We hypothesized that patients with colonic neoplasia have altered colonic epithelial ion transport and express functionally different prostanoid receptor levels in this respect. Methods Patients referred for colonoscopy were included and grouped into patients with and without colorectal neoplasia. Patients without endoscopic findings of neoplasia served as controls. Biopsy specimens were obtained from normally appearing mucosa in the sigmoid part of colon. Biopsies were mounted in miniaturized modified Ussing air-suction chambers. Indomethacin (10 μM, various stimulators and inhibitors of prostanoid receptors and ion transport were subsequently added to the chamber solutions. Electrogenic ion transport parameters (short circuit current and slope conductance were recorded. Tissue pathology and tissue damage before and after experiments was assessed by histology. Results Baseline short circuit current and slope conductance did not differ between the two groups. Patients with neoplasia were significantly more sensitive to indomethacin with a decrease in short circuit current of 15.1 ± 2.6 μA·cm-2 compared to controls, who showed a decrease of 10.5 ± 2.1 μA·cm-2 (p = 0.027. Stimulation or inhibition with theophylline, ouabain, bumetanide, forskolin or the EP receptor agonists prostaglandin E2, butaprost, sulprostone and prostaglandin E1 (OH did not differ significantly between the two groups. Histology was with normal findings in both groups. Conclusions Epithelial electrogenic transport is more sensitive to indomethacin in normal colonic mucosa from patients with previous or present colorectal neoplasia compared

  2. Pyometra in Bitches Induces Elevated Plasma Endotoxin and Prostaglandin F2α Metabolite Levels

    Science.gov (United States)

    Hagman, R; Kindahl, H; Lagerstedt, A-S

    2006-01-01

    Endotoxemia in bitches with pyometra can cause severe systemic effects directly or via the release of inflammatory mediators. Plasma endotoxin concentrations were measured in ten bitches suffering from pyometra with moderately to severely deteriorated general condition, and in nine bitches admitted to surgery for non-infectious reasons. Endotoxin samples were taken on five occasions before, during and after surgery. In addition, urine and uterine bacteriology was performed and hematological, blood biochemical parameters, prostaglandin F2α metabolite 15-ketodihydro-PGF2α (PG-metabolite), progesterone and oestradiol (E2-17β) levels were analysed. The results confirm significantly increased plasma levels of endotoxin in bitches with pyometra and support previous reports of endotoxin involvement in the pathogenesis of the disease. Plasma concentrations of PG-metabolite were elevated in pyometra bitches and provide a good indicator of endotoxin release since the concentrations were significantly correlated to the endotoxin levels and many other hematological and chemistry parameters. The γ-globulin serum protein electrophoresis fraction and analysis of PG-metabolite can be valuable in the diagnosis of endotoxin involvement if a reliable, rapid and cost-effective test for PG-metabolite analysis becomes readily available in the future. Treatment inhibiting prostaglandin biosynthesis and related compounds could be beneficial for bitches suffering from pyometra. PMID:16722306

  3. Pyometra in Bitches Induces Elevated Plasma Endotoxin and Prostaglandin F2α Metabolite Levels

    Directory of Open Access Journals (Sweden)

    Hagman R

    2006-03-01

    Full Text Available Endotoxemia in bitches with pyometra can cause severe systemic effects directly or via the release of inflammatory mediators. Plasma endotoxin concentrations were measured in ten bitches suffering from pyometra with moderately to severely deteriorated general condition, and in nine bitches admitted to surgery for non-infectious reasons. Endotoxin samples were taken on five occasions before, during and after surgery. In addition, urine and uterine bacteriology was performed and hematological, blood biochemical parameters, prostaglandin F2α metabolite 15-ketodihydro-PGF2α (PG-metabolite, progesterone and oestradiol (E2-17β levels were analysed. The results confirm significantly increased plasma levels of endotoxin in bitches with pyometra and support previous reports of endotoxin involvement in the pathogenesis of the disease. Plasma concentrations of PG-metabolite were elevated in pyometra bitches and provide a good indicator of endotoxin release since the concentrations were significantly correlated to the endotoxin levels and many other hematological and chemistry parameters. The γ-globulin serum protein electrophoresis fraction and analysis of PG-metabolite can be valuable in the diagnosis of endotoxin involvement if a reliable, rapid and cost-effective test for PG-metabolite analysis becomes readily available in the future. Treatment inhibiting prostaglandin biosynthesis and related compounds could be beneficial for bitches suffering from pyometra.

  4. Conceptus elongation in ruminants: roles of progesterone, prostaglandin, interferon tau and cortisol.

    Science.gov (United States)

    Brooks, Kelsey; Burns, Greg; Spencer, Thomas E

    2014-01-01

    The majority of pregnancy loss in ruminants occurs during the first three weeks after conception, particularly during the period of conceptus elongation that occurs prior to pregnancy recognition and implantation. This review integrates established and new information on the biological role of ovarian progesterone (P4), prostaglandins (PGs), interferon tau (IFNT) and cortisol in endometrial function and conceptus elongation. Progesterone is secreted by the ovarian corpus luteum (CL) and is the unequivocal hormone of pregnancy. Prostaglandins (PGs) and cortisol are produced by both the epithelial cells of the endometrium and the trophectoderm of the elongating conceptus. In contrast, IFNT is produced solely by the conceptus trophectoderm and is the maternal recognition of pregnancy signal that inhibits production of luteolytic pulses of PGF2α by the endometrium to maintain the CL and thus production of P4. Available results in sheep support the idea that the individual, interactive, and coordinated actions of P4, PGs, IFNT and cortisol regulate conceptus elongation and implantation by controlling expression of genes in the endometrium and/or trophectoderm. An increased knowledge of conceptus-endometrial interactions during early pregnancy in ruminants is necessary to understand and elucidate the causes of infertility and recurrent early pregnancy loss and provide new strategies to improve fertility and thus reproductive efficiency.

  5. A Novel Selective Prostaglandin E2 Synthesis Inhibitor Relieves Pyrexia and Chronic Inflammation in Rats.

    Science.gov (United States)

    Sugita, Ryusuke; Kuwabara, Harumi; Sugimoto, Kotaro; Kubota, Kazufumi; Imamura, Yuichiro; Kiho, Toshihiro; Tengeiji, Atsushi; Kawakami, Katsuhiro; Shimada, Kohei

    2016-04-01

    Prostaglandin E2 (PGE2) is a terminal prostaglandin in the cyclooxygenase (COX) pathway. Inhibition of PGE2 production may relieve inflammatory symptoms such as fever, arthritis, and inflammatory pain. We report here the profile of a novel selective PGE2 synthesis inhibitor, compound A [N-[(1S,3S)-3-carbamoylcyclohexyl]-1-(6-methyl-3-phenylquinolin-2-yl)piperidine-4-carboxamide], in animal models of pyrexia and inflammation. The compound selectively suppressed the synthesis of PGE2 in human alveolar adenocarcinoma cell line A549 cells and rat macrophages. In the lipopolysaccharide-induced pyrexia model, this compound selectively reduced PGE2 production in cerebrospinal fluid and showed an anti-pyretic effect. In the adjuvant-induced arthritis model, compound A therapeutically decreased foot swelling in the established arthritis. Our data demonstrates that selective suppression of PGE2 synthesis shows anti-pyretic and anti-inflammatory effects, suggesting that selective PGE2 synthesis inhibitors can be applied as an alternative treatment to nonsteroidal, anti-inflammatory drugs (NSAIDs) or COX-2-selective inhibitors.

  6. Decreased RORC-dependent silencing of prostaglandin receptor EP2 induces autoimmune Th17 cells.

    Science.gov (United States)

    Kofler, David M; Marson, Alexander; Dominguez-Villar, Margarita; Xiao, Sheng; Kuchroo, Vijay K; Hafler, David A

    2014-06-01

    Prostaglandin E2 (PGE2) promotes Th17 expansion while otherwise inhibiting other CD4+ T cell subsets. Here, we identified a PGE2-dependent pathway that induces pathogenic Th17 cells in autoimmune disease and is regulated by the transcription factor RORC. Compared with other CD4+ cell types from healthy subjects, there is a surprising lack of the prostaglandin receptor EP2 on Th17 cells; therefore, we examined the hypothesis that RORγt, which is highly expressed in Th17 cells, mediates EP2 downregulation. Chromatin immunoprecipitation followed by DNA sequencing revealed that RORγt binds directly to Ptger2 (the gene encoding EP2 receptor) in Th17 cells isolated from WT mice. In Th17 cells isolated from humans, RORC repressed EP2 by directly silencing PTGER2 transcription, and knock down of RORC restored EP2 expression in Th17 cells. Compared with Th17 cells from healthy individuals, Th17 cells from patients with MS exhibited reduced RORC binding to the PTGER2 promoter region, resulting in higher EP2 levels and increased expression of IFN-γ and GM-CSF. Finally, overexpression of EP2 in Th17 cells from healthy individuals induced a specific program of inflammatory gene transcription that produced a pathogenic Th17 cell phenotype. These findings reveal that RORC directly regulates the effects of PGE2 on Th17 cells, and dysfunction of this pathway induces a pathogenic Th17 cell phenotype.

  7. [Receptors involved in the mechanism of action of topical prostaglandines].

    Science.gov (United States)

    Neacsu, Alina Mihaela

    2009-01-01

    Hypotensive effect to prostaglandins analogs (latanoprost, travoprost, tafluprost) means to increase uveoscleral outflow by action to FP receptors who generated extracellular matrix changes and intermuscular spaces changes. Syntetic prostamides analogs (bimatoprost) have a particulary action with a receptors most and intensive studied. The bimatoprost effect is the consequences to preferated stimulations on the specific receptors who have action only the tissue with prostaglandins activity is important to specify what the bimatoprost have dual effect: to uveoscleral outflow and classic outflow by increase hidraulic conductivity.

  8. A20 overexpression under control of mouse osteocalcin promoter in MC3T3-E1 cells inhibited tumor necrosis factor-alpha-induced apoptosis

    Institute of Scientific and Technical Information of China (English)

    Yue-juan QIN; Zhen-lin ZHANG; Lu-yang YU; Jin-wei HE; Ya-nan HOU; Tian-jin LIU; Jia-cai WU; Song-hua WU; Li-he GUO

    2006-01-01

    Aim: To construct an A20 expression vector under the control of mouse osteocalcin promoter (OC-A20), and investigate osteoblastic MC3T3-E1 cell line, which stably overexpresses A20 protein prevented tumor necrosis factor (TNF)-alpha-induced apoptosis. Methods: OC-A20 vector was constructed by fusing a fragment of the mouse osteocalcin gene-2 promoter with human A20 complementary DNA. Then the mouse MC3T3-E1 cell line,