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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

    Directory of Open Access Journals (Sweden)

    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. Arecoline inhibits interleukin-2 secretion in Jurkat cells by decreasing the expression of alpha7-nicotinic acetylcholine receptors and prostaglandin E2.

    Science.gov (United States)

    Hwang, G S; Hu, S; Lin, Y H; Chen, S T; Tang, T K; Wang, P S; Wang, S W

    2013-10-01

    The purpose of the present study was to explore the effect of arecoline on phytohemagglutinin (PHA)-stimulated interleukin-2 (IL-2) secretion, the expression of alpha7-nicotinic acetylcholine receptors (α7-nAChRs), prostaglandin E2(PGE2) protein, and IL-2 mRNA in human lymphocyte cells (Jurkat cell line). The IL-2 and PGE2 were determined by enzyme-linked immunosorbent assay (ELISA). The expressions of phosphorylated extracellular signal-regulated kinase (ERK) and α7-nAChRs were determined by Western blotting. The level of IL-2 mRNA was determined by reverse-transcriptase polymerase chain reaction (RT-PCR). Arecoline, in a dose-dependent manner, significantly decreased IL-2 and PGE2 secretion by Jurkat cells incubated with 0 or 5 μg/ml 5 μg/ml PHA. PGE2 also significantly inhibited IL-2 secretion by Jurkat cells in a dose-dependent manner. In addition, reduced expression of PHA-induced ERK phosphorylation was observed in Jurkat cells treated with arecoline. PHA-enhanced IL-2 mRNA expression was also inhibited by arecoline. These results imply that arecoline inhibits the release of PGE2 and PHA-induced IL-2 secretion by Jurkat cells and that these effects seem to occur, at least in part, either through the attenuation of ERK in conjunction with a decrease of PHA-induced IL-2 mRNA expression. These results imply that arecoline inhibits the protein expression of α7-nAChRs , the release of PGE2 and PHA-induced IL-2 secretion by Jurkat cells.

  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.

    Science.gov (United States)

    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. 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...

  5. The effect of prostaglandins E1, E2 and F2 alpha and indomethacin on the sensitivity of glycolysis and glycogen synthesis to insulin in stripped soleus muscles of the rat.

    Science.gov (United States)

    Leighton, B; Budohoski, L; Lozeman, F J; Challiss, R A; Newsholme, E A

    1985-01-01

    Prostaglandins E1 and E2 increased the sensitivity of glycolysis to insulin in the isolated stripped soleus muscle of the rat, but prostaglandin F2 alpha had no effect. Indomethacin, which inhibits prostaglandin formation, markedly decreased the sensitivity of glycolysis to insulin. These findings suggest that prostaglandins of the E series increase the sensitivity of muscle glycolysis to insulin in vivo. PMID:3888199

  6. Inhibition of peristalsis in guinea-pig isolated ileum and colon by drugs that block prostaglandin synthesis.

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    Bennett, A; Eley, K G; Stockley, H L

    1976-01-01

    1 Methods of analysing peristaltic activity have been evaluated by the use of recordings of longitudinal and circular muscle activity and of propulsion in whole segments of guinea-pig ileum and colon. 2 Some prostaglandin synthesis inhibitors, and antagonists of prostaglandin action were tested for their suitability for studying the role of prostaglandins in peristalsis. Aspirin was suitable; at 10-200 mug/ml it had little effect on responses of longitudinal muscle strips of the guinea-pig ileum to acetylcholine (ACh), histamine, nicotine or prostaglandin E2. Indomethacin (1-4 mug/ml) reduced responses to nicotine and prostaglandin E2. The prostaglandin antagonists polyphloretin phosphate and SC-19220 reduced contractions of ileal longitudinal muscle caused by nerve excitation with either nicotine or transmural stimulation. 3 Aspirin (20-100 mug/ml) or indomethacin (1-4 mug/ml) applied serosally greatly inhibited all aspects of peristalsis in guinea-pig ileum and colon. Inhibition of peristalsis of the ileum by aspirin was antagonized by prostaglandin E2 and that by indomethacin was removed by prostaglandin F2alpha or ACh. Inhibition of colonic peristalsis by aspirin was antagonized by prostaglandin E2 but rarely by ACh, and that by indomethacin by prostaglandin E1 or E2. Mucosal application of aspirin had little effect on either ileum or colon but indomethacin caused some inhibition. 4 These results support the supposition that prostaglandins contribute to peristaltic activity. PMID:823997

  7. 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...... that exhibit mild polyuria and polydipsia. Atherogenesis is retarded by deletion of the FP, despite the absence of detectable receptor expression in aorta or in atherosclerotic lesions in Ldlr KOs. Although vascular TNF(alpha), inducible nitric oxide enzyme and TGF(beta) are reduced and lesional macrophages...... are depleted in the FP/Ldlr double KOs, this result reflects the reduction in lesion burden, as the FP is not expressed on macrophages and its deletion does not alter macrophage cytokine generation. Blockade of the FP offers an approach to the treatment of hypertension and its attendant systemic vascular...

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

    DEFF Research Database (Denmark)

    Lerche, A; Bisgaard, H; Kassis, V

    1989-01-01

    Ten nickel-allergic patients and 5 healthy control subjects participated in a study of the kinetics of the flux and concentration of migrated leukocytes and extracellular PGE1 and PGF2 alpha during a 48 h period, using a skin chamber technique. The patients were provided with two skin chambers, one...... 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...

  9. Anti-inflammatory effects of the butanolic fraction of Byrsonima verbascifolia leaves: Mechanisms involving inhibition of tumor necrosis factor alpha, prostaglandin E(2) production and migration of polymorphonuclear leucocyte in vivo experimentation.

    Science.gov (United States)

    Saldanha, Aline Aparecida; de Siqueira, João Máximo; Castro, Ana Hortência Fonsêca; de Azambuja Ribeiro, Rosy Iara Maciel; de Oliveira, Flávio Martins; de Oliveira Lopes, Débora; Pinto, Flávia Carmo Horta; Silva, Denise Brentan; Soares, Adriana Cristina

    2016-02-01

    The leaves of Byrsonima verbascifolia (Malpighiaceae) are traditionally used to treat various diseases including inflammatory conditions. The main goal of this study was to evaluate the in vivo anti-inflammatory activity of the polar constituents from the butanolic fraction of B. verbascifolia leaves (BvBF), as well as to investigate the mechanisms involved in the anti-inflammatory activity. The polar constituents were identified by liquid chromatography coupled to diode array detector and mass spectrometry (LC-DAD–MS) and matrix-assisted laser desorption/ionization – time-of-flight mass spectrometry (MALDI-TOF MS) to obtain a complete chemical profile of the fraction. Forty-five compounds were detected in the BvBF by LC-DAD–MS/MS, including condensed tannins, phenolic acids, flavonoids (flavones and flavonols) and other compounds. In addition, several condensed tannins were identified by MALDI-MS/MS, which are composed predominantly by procyanidin units (PCY) and up to six flavan-3-ol units. The BvBF exhibited significant antioxidant and anti-inflammatory activities. The BvBF inhibited paw edema and polymorphonuclear (PMN) leukocyte migration to the footpad and pleural cavity induced by carrageenan. Furthermore, a minor dose (12.50 mg/kg) of BvBF effectively decreased tumor necrosis factor alpha (TNF-α) and prostaglandin E2 (PGE2) levels in the footpad. These findings suggest that the mechanism of the anti-inflammatory action in the BvBF is linked to the inhibition of the production of inflammatory mediators such as TNF-α and PGE2 and the PMN cell migration.

  10. Inhibition of Nitric Oxide and Prostaglandin E 2 Expression by ...

    African Journals Online (AJOL)

    Inhibition of Nitric Oxide and Prostaglandin E2 Expression by Methanol Extract of Polyopes affinis in Lipopolysaccharide-stimulated BV2 Microglial Cells through Suppression of Akt-dependent NF-kB Activity and MAPK Pathway. RGPT Jayasooriya, Y-J Jang, C-H Kang, MG Dilshara, D-O Moon, T-J Nam, YH Choi, G-Y Kim ...

  11. Studies on prostaglandin F2 alpha formation caused by pentametylenetetrazol-induced convulsions in rat brain.

    Science.gov (United States)

    Seregi, A; Folly, G; Antal, M; Serfözö, P; Schaefer, A

    1981-02-01

    Prostaglandin F2 alpha formation caused by pentametylenetetrazol convulsions was studied as a function of the duration, the doses of the convulsant and the intensity of the seizures. It was shown by the statistical analysis of the results in the case of clonic convulsions that the amount of synthetized PGF2 alpha did not depend on the doses of convulsant, while close relation existed between the duration and the PGF2 alpha production. At the same time, during tonic convulsions lasting longer than 50 sec, no more increase in the PGF2 alpha content of the brain was observed. An experimental model is suggested to study in vivo the mechanisms regulating the brain's prostaglandin biosynthesis. Pretreatment of the animals with reserpine did not affect the rate of convulsion-induced PGF2 alpha-formation.

  12. Prostaglandin E and F2 alpha receptors in human myometrium during the menstrual cycle and in pregnancy and labor

    International Nuclear Information System (INIS)

    Giannopoulos, G.; Jackson, K.; Kredentser, J.; Tulchinsky, D.

    1985-01-01

    The binding of prostaglandins E1 and F2 alpha has been studied in the human myometrium and cervix during the menstrual cycle and in the myometrium of pregnant patients at term before and during labor. Tritium-labeled prostaglandin E1 and F2 alpha binding was saturable and reversible. Scatchard analysis of tritium-labeled prostaglandin E1 binding was linear, which suggests a single class of high-affinity binding sites with an estimated apparent equilibrium dissociation constant of 2.5 to 5.4 nmol/L and inhibitor affinities of 0.9, 273, 273, and 217 nmol/L for prostaglandins E2, A1, B1, and F2 alpha, respectively. Scatchard analysis of tritium-labeled prostaglandin F2 alpha, binding was also linear, but the affinity of these binding sites was much lower, with an average dissociation constant of 50 nmol/L and inhibitor affinities of 1.6, 2.2, and 11.2 nmol/L for prostaglandins E1, E2, and A1, respectively. In nonpregnant patients, the concentrations and affinities of tritium-labeled prostaglandin E1 binding sites were similar in the myometrium during the proliferative and secretory phases of the menstrual cycle, but the concentration of these sites was much lower in the cervix. The concentration of the tritium-labeled prostaglandin E1 binding sites was significantly lower in the myometrium of pregnant patients at term than in the myometrium of nonpregnant patients. The concentrations and affinities of tritium-labeled prostaglandin E1 binding sites were not significantly different in the upper and lower myometrium of pregnant patients at term or in the myometrium of such patients before and during labor. The concentrations of the tritium-labeled prostaglandin F2 alpha binding sites during the menstrual cycle and in pregnancy at term were similar to those of tritium-labeled prostaglandin E1 binding sites

  13. Prostaglandin E and F2 alpha receptors in human myometrium during the menstrual cycle and in pregnancy and labor

    Energy Technology Data Exchange (ETDEWEB)

    Giannopoulos, G.; Jackson, K.; Kredentser, J.; Tulchinsky, D.

    1985-12-15

    The binding of prostaglandins E1 and F2 alpha has been studied in the human myometrium and cervix during the menstrual cycle and in the myometrium of pregnant patients at term before and during labor. Tritium-labeled prostaglandin E1 and F2 alpha binding was saturable and reversible. Scatchard analysis of tritium-labeled prostaglandin E1 binding was linear, which suggests a single class of high-affinity binding sites with an estimated apparent equilibrium dissociation constant of 2.5 to 5.4 nmol/L and inhibitor affinities of 0.9, 273, 273, and 217 nmol/L for prostaglandins E2, A1, B1, and F2 alpha, respectively. Scatchard analysis of tritium-labeled prostaglandin F2 alpha, binding was also linear, but the affinity of these binding sites was much lower, with an average dissociation constant of 50 nmol/L and inhibitor affinities of 1.6, 2.2, and 11.2 nmol/L for prostaglandins E1, E2, and A1, respectively. In nonpregnant patients, the concentrations and affinities of tritium-labeled prostaglandin E1 binding sites were similar in the myometrium during the proliferative and secretory phases of the menstrual cycle, but the concentration of these sites was much lower in the cervix. The concentration of the tritium-labeled prostaglandin E1 binding sites was significantly lower in the myometrium of pregnant patients at term than in the myometrium of nonpregnant patients. The concentrations and affinities of tritium-labeled prostaglandin E1 binding sites were not significantly different in the upper and lower myometrium of pregnant patients at term or in the myometrium of such patients before and during labor. The concentrations of the tritium-labeled prostaglandin F2 alpha binding sites during the menstrual cycle and in pregnancy at term were similar to those of tritium-labeled prostaglandin E1 binding sites.

  14. The formation and regional distribution of prostaglandins D2 and F2 alpha in the brain of spontaneously convulsing gerbils.

    Science.gov (United States)

    Seregi, A; Förstermann, U; Heldt, R; Hertting, G

    1985-06-24

    The distribution of the two major cyclooxygenase products prostaglandin D2 (PGD2) and prostaglandin F2 alpha (PGF2 alpha) in 7 different regions of the brain (medulla, cerebellum, hypothalamus, striatum, midbrain, hippocampus and cerebral cortex) was studied. Basal levels were highest in hypothalamus and cortex. Following convulsions elicited by environmental stress prostaglandin concentrations increased in all areas, with largest increases (10-20-fold) in hippocampus and cortex, reaching 70 ng/g PGD2 in hippocampus and 115 ng/g PGD2 in cortex. These results demonstrate that, during spontaneous seizures, there is a greater increase in prostanoid production in those areas involved in the convulsive process.

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

    DEFF Research Database (Denmark)

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

    1988-01-01

    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......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...... chain (n-3)-fatty acids. We have hypothesized that a high intake of long chain (n-3)-fatty acids prolongs gestation in humans by interfering with uterine prostaglandin formation, possibly by inhibiting formation of prostaglandin F2 alpha and prostaglandin E2. Preliminary results of an epidemiological...

  16. Prostaglandins E1 and E2 inhibit lipopolysaccharide-induced interleukin-18 production in monocytes.

    Science.gov (United States)

    Takahashi, Hideo K; Iwagaki, Hiromi; Mori, Shuji; Yoshino, Tadashi; Tanaka, Noriaki; Nishibori, Masahiro

    2005-07-11

    The purpose of this present study was to explore the therapeutic potential of prostaglandins E1 and E2 on the systemic inflammatory response evoked by endotoxin. Since interleukin-18, a monocyte-derived cytokine, is increased during sepsis, decreasing the production of interleukin-18 is important in treating this condition. Prostaglandin E1 and E2 inhibited interleukin-18 production in human monocytes treated with lipopolysaccharide and prostanoid IP-, EP2- and EP4-receptor agonists mimicked the effects of prostaglandins E1 and E2. Therefore, prostanoid IP, EP2- and EP4-receptors might be involved in the decrease in interleukin-18 production during sepsis.

  17. The effect of prostaglandin inhibition on the development of pulmonary pathology associated with dead Dirofilaria immitis.

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    Tarish, J H; Atwell, R B

    1993-09-01

    Flunixin meglumine was used to examine the effect of prostaglandin inhibition on the pathogenesis of Dirofilaria immitis in the pulmonary arteries of dogs. Immunopathological reactions to dead filariae were monitored by light and transmission electron microscopy and serology. Lung lesions in prostaglandin-inhibited dogs exposed to dead filariae were enhanced compared to control dogs. This was associated with the persistence of parasitic antigen in lung tissue and in the blood. Serology demonstrated that after insertion of D. immitis in treated dogs, antibody levels did not change, while immune complex and antigen levels increased. These results indicate that prostaglandin may have a protective effect on the way the lung reacts to dead D. immitis, and that altered dynamics of the antigen processing may well contribute to the associated lung lesions.

  18. 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...

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

    Directory of Open Access Journals (Sweden)

    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.

  20. Prostaglandin F2 alpha and progesterone profiles in post-partum cows with short luteal phases.

    Science.gov (United States)

    Bekana, M

    1997-01-01

    Sequential blood samples were collected at 3 h interval from 3 Swedish dairy cows starting from the day of first post-partum ovulation for 10 consecutive days to describe short luteal phases. All plasma samples were analysed for the concentrations of the main PGF2 alpha metabolite, 15-ketodihydro-PGF2 alpha, whereas levels of progesterone were monitored from all morning samples. The day of ovulation was judged when the largest follicle, being monitored by a real-time B mode ultrasound scanner, could not be detected at the next examination. A sustained rise above 0.5 nmol/l of progesterone level was taken as a clear-cut value between non-luteal and luteal phases. Luteal phases of less than 8 days were registered as a short luteal phase during which the cows showed a total of 8 to 11 significantly elevated levels of the prostaglandin metabolite. The number of the significant increases of the metabolite was calculated using a skewness method. Analysis of these significant increases showed the first 1 to 4 episodes without altering the concentrations of progesterone. This would suggest that the developing corpus luteum is refractory in the beginning and thus, to induce luteolysis several PGF 2 alpha releases are required. The magnitude of progesterone concentrations during the short luteal phase is lower than the following phases.

  1. Loss of platelet alpha 2-adrenergic receptors during simulated extracorporeal circulation: prevention with prostaglandin E1

    Energy Technology Data Exchange (ETDEWEB)

    Wachtogel, Y.T.; Musial, J.; Jenkin, B.; Niewiarowski, S.; Edmunds, L.H. Jr.; Colman, R.W.

    1985-05-01

    Cardiopulmonary bypass prolongs bleeding time and increases postoperative blood loss. During in vitro recirculation in an extracorporeal circuit containing a membrane oxygenator and primed with fresh heparinized human blood, the authors previously observed thrombocytopenia, impaired platelet aggregation, and depletion of granular contents, all of which were prevented with prostaglandin E1 (PGE1). To investigate these changes further, they studied the number and affinity of platelet alpha 2-adrenergic receptors by measuring the binding of /sup 3/H-yohimbine. Before recirculation, they found 235 alpha 2-adrenergic receptors per platelet, a Kd of 3.37 nmol/L, complete aggregation with 1.04 mumol/L epinephrine, and a platelet count of 281,000 microliters/sup -1/. After 2 minutes of recirculation, 9.44 mumol/L epinephrine was required to produce complete aggregation, and the platelet count was 104,000 microliters-1 (44% of control). After 2 hours of recirculation, the platelet count had increased to 123,000 microliters/sup -1/. However, epinephrine did not induce platelet aggregation even at 100 mumol/L. Moreover, alpha 2-adrenergic binding sites were not detectable, and affinity for yohimbine could not be calculated. Two minutes after PGE1 0.3 mumol/L was added to the circuit, platelet numbers, response to epinephrine, alpha 2-adrenergic binding sites per platelet, and affinity for yohimbine were not significantly different from control values. At 2 hours, the number of alpha 2-adrenergic sites was not significantly changed from control, but the affinity of yohimbine for platelets was significantly decreased 2.5-fold.

  2. Loss of platelet alpha 2-adrenergic receptors during simulated extracorporeal circulation: prevention with prostaglandin E1

    International Nuclear Information System (INIS)

    Wachtogel, Y.T.; Musial, J.; Jenkin, B.; Niewiarowski, S.; Edmunds, L.H. Jr.; Colman, R.W.

    1985-01-01

    Cardiopulmonary bypass prolongs bleeding time and increases postoperative blood loss. During in vitro recirculation in an extracorporeal circuit containing a membrane oxygenator and primed with fresh heparinized human blood, the authors previously observed thrombocytopenia, impaired platelet aggregation, and depletion of granular contents, all of which were prevented with prostaglandin E1 (PGE1). To investigate these changes further, they studied the number and affinity of platelet alpha 2-adrenergic receptors by measuring the binding of 3 H-yohimbine. Before recirculation, they found 235 alpha 2-adrenergic receptors per platelet, a Kd of 3.37 nmol/L, complete aggregation with 1.04 mumol/L epinephrine, and a platelet count of 281,000 microliters -1 . After 2 minutes of recirculation, 9.44 mumol/L epinephrine was required to produce complete aggregation, and the platelet count was 104,000 microliters-1 (44% of control). After 2 hours of recirculation, the platelet count had increased to 123,000 microliters -1 . However, epinephrine did not induce platelet aggregation even at 100 mumol/L. Moreover, alpha 2-adrenergic binding sites were not detectable, and affinity for yohimbine could not be calculated. Two minutes after PGE1 0.3 mumol/L was added to the circuit, platelet numbers, response to epinephrine, alpha 2-adrenergic binding sites per platelet, and affinity for yohimbine were not significantly different from control values. At 2 hours, the number of alpha 2-adrenergic sites was not significantly changed from control, but the affinity of yohimbine for platelets was significantly decreased 2.5-fold

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

    International Nuclear Information System (INIS)

    Collins, D.A.; Chambers, T.J.

    1991-01-01

    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 - 6 -10 - 9 M) and PGE1 (10 - 6 - 10 - 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 - 7 M PGE2 and 10 - 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

  4. Prostaglandin F2alpha differentially affects mRNA expression relating to angiogenesis, vasoactivation and prostaglandins in the early and mid corpus luteum in the cow.

    Science.gov (United States)

    Shirasuna, Koumei; Sasahara, Kiemi; Matsui, Motozumi; Shimizu, Takashi; Miyamoto, Akio

    2010-08-01

    Administration of prostaglandin (PG) F(2alpha) in cattle during the mid-luteal phase (Days 8-12 of the estrous cycle) drastically reduces the plasma progesterone concentrations and the volume of the corpus luteum (CL). However, PGF(2alpha) does not induce luteolysis during the early luteal phase (up to Day 5 of the estrous cycle). To characterize the possible distinct difference in acute response to a luteolytic dose of PGF(2alpha) administration, we determined various mRNA expressions in the early and mid CL relating to angiogenesis, vasoactivation and PG-related factors at 30 min after PGF(2alpha) injection in cyclic cows. The experiments were conducted on Day 4 (early CL) and Days 10-12 (mid CL). Cows were either injected with 500 microg PGF(2alpha) analogue or saline as the control (early CL control, n=5; early CL PGF(2alpha) treated, n=5; mid CL control, n=5; mid CL PGF(2alpha) treated, n=7). Thirty min after injection of PGF(2alpha) or saline, the cows were ovariectomized transvaginally, and the CL tissues were collected from regions designated as the periphery and center of the CL. Administration of PGF(2alpha) up-regulated the mRNA expressions of angiogenic-related factors such as vascular endothelial growth factors, vasohibin, fibroblast growth factor 2 and insulin-like growth factor-II in the early CL, whereas PGF(2alpha) down-regulated these mRNA expressions in the mid CL. In the vasoactive factors, PGF(2alpha) stimulated the mRNA expressions of endothelin-1, angiotensin converting enzyme, endothelial nitric oxide synthase (NOS) and inducible NOS in the periphery area of the mid CL, but not in the early CL. However, PGF(2alpha) drastically down-regulated PGF(2alpha) receptor mRNA expression in both regions of the early and mid CL. The results indicated a clear difference in the acute action of PGF(2alpha) depending not only on the luteal phase (immature vs. mature) but also the region (periphery vs. center) within the CL at 30 min after PGF(2alpha

  5. 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.

  6. 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....

  7. Prostaglandin F2 alpha stimulates phosphatidylinositol 4,5-bisphosphate hydrolysis and mobilizes intracellular Ca2+ in bovine luteal cells

    International Nuclear Information System (INIS)

    Davis, J.S.; Weakland, L.L.; Weiland, D.A.; Farese, R.V.; West, L.A.

    1987-01-01

    The present studies were conducted to determine whether prostaglandin F2 alpha (PGF2 alpha) stimulates the production of ''second messengers'' derived from inositol phospholipid hydrolysis and increases intracellular free Ca2+ ([Ca2+]i) in isolated bovine luteal cells. PGF2 alpha provoked rapid (10 sec) and sustained (up to 60 min) increases in the levels of inositol mono-, bis-, and trisphosphates (InsP, InsP2, and InsP3, respectively). InsP3 was formed more rapidly than InsP2 or InsP after PGF2 alpha treatment. In addition, PGF2 alpha increased inositol phospholipid turnover, as evidenced by increased 32 PO 4 incorporation into phosphatidic acid and phosphatidylinositol. LiCl (1-20 mM) enhanced inositol phosphate accumulation in response to PGF2 alpha. Maximal increases in InsP3 occurred at 1 microM PGF2 alpha, with half-maximal stimulation occurring at 36 nM. The acute effects of PGF2 alpha on InsP3 levels were independent of reductions in extracellular calcium. Prostaglandins E1 and E2 also stimulated increases in inositol phosphate levels, albeit to a lesser extent. PGF2 alpha also induced rapid and concentration-dependent increases in [Ca2+]i as measured by quin-2 fluorescence. The PGF2 alpha-induced increases in [Ca2+]i were maximal within 30 sec (approximately 2- to 3-fold), and [Ca2+]i remained elevated for 8-10 min. The PGF2 alpha-induced increases in [Ca2+]i were also independent of extracellular calcium. These findings demonstrate that the action of PGF2 alpha is coupled to the phospholipase C-InsP3 and diacylglycerol second messenger system in the corpus luteum

  8. Prostaglandin F2 alpha stimulates phosphatidylinositol 4,5-bisphosphate hydrolysis and mobilizes intracellular Ca2+ in bovine luteal cells

    Energy Technology Data Exchange (ETDEWEB)

    Davis, J.S.; Weakland, L.L.; Weiland, D.A.; Farese, R.V.; West, L.A.

    1987-06-01

    The present studies were conducted to determine whether prostaglandin F2 alpha (PGF2 alpha) stimulates the production of ''second messengers'' derived from inositol phospholipid hydrolysis and increases intracellular free Ca2+ ((Ca2+)i) in isolated bovine luteal cells. PGF2 alpha provoked rapid (10 sec) and sustained (up to 60 min) increases in the levels of inositol mono-, bis-, and trisphosphates (InsP, InsP2, and InsP3, respectively). InsP3 was formed more rapidly than InsP2 or InsP after PGF2 alpha treatment. In addition, PGF2 alpha increased inositol phospholipid turnover, as evidenced by increased /sup 32/PO/sub 4/ incorporation into phosphatidic acid and phosphatidylinositol. LiCl (1-20 mM) enhanced inositol phosphate accumulation in response to PGF2 alpha. Maximal increases in InsP3 occurred at 1 microM PGF2 alpha, with half-maximal stimulation occurring at 36 nM. The acute effects of PGF2 alpha on InsP3 levels were independent of reductions in extracellular calcium. Prostaglandins E1 and E2 also stimulated increases in inositol phosphate levels, albeit to a lesser extent. PGF2 alpha also induced rapid and concentration-dependent increases in (Ca2+)i as measured by quin-2 fluorescence. The PGF2 alpha-induced increases in (Ca2+)i were maximal within 30 sec (approximately 2- to 3-fold), and (Ca2+)i remained elevated for 8-10 min. The PGF2 alpha-induced increases in (Ca2+)i were also independent of extracellular calcium. These findings demonstrate that the action of PGF2 alpha is coupled to the phospholipase C-InsP3 and diacylglycerol second messenger system in the corpus luteum.

  9. Prostaglandin E1 inhibits endocytosis in the β-cell endocytosis.

    Science.gov (United States)

    Zhao, Ying; Fang, Qinghua; Straub, Susanne G; Lindau, Manfred; Sharp, Geoffrey W G

    2016-06-01

    Prostaglandins inhibit insulin secretion in a manner similar to that of norepinephrine (NE) and somatostatin. As NE inhibits endocytosis as well as exocytosis, we have now examined the modulation of endocytosis by prostaglandin E1 (PGE1). Endocytosis following exocytosis was recorded by whole-cell patch clamp capacitance measurements in INS-832/13 cells. Prolonged depolarizing pulses producing a high level of Ca(2+) influx were used to stimulate maximal exocytosis and to deplete the readily releasable pool (RRP) of granules. This high Ca(2+) influx eliminates the inhibitory effect of PGE1 on exocytosis and allows specific characterization of the inhibitory effect of PGE1 on the subsequent compensatory endocytosis. After stimulating exocytosis, endocytosis was apparent under control conditions but was inhibited by PGE1 in a Pertussis toxin-sensitive (PTX)-insensitive manner. Dialyzing a synthetic peptide mimicking the C-terminus of the α-subunit of the heterotrimeric G-protein Gz into the cells blocked the inhibition of endocytosis by PGE1, whereas a control-randomized peptide was without effect. These results demonstrate that PGE1 inhibits endocytosis and Gz mediates the inhibition. © 2016 Society for Endocrinology.

  10. The human multidrug resistance protein MRP4 functions as a prostaglandin efflux transporter and is inhibited by nonsteroidal antiinflammatory drugs

    Science.gov (United States)

    Reid, Glen; Wielinga, Peter; Zelcer, Noam; van der Heijden, Ingrid; Kuil, Annemieke; de Haas, Marcel; Wijnholds, Jan; Borst, Piet

    2003-01-01

    Prostaglandins are involved in a wide variety of physiological and pathophysiological processes, but the mechanism of prostaglandin release from cells is not completely understood. Although poorly membrane permeable, prostaglandins are believed to exit cells by passive diffusion. We have investigated the interaction between prostaglandins and members of the ATP-binding cassette (ABC) transporter ABCC [multidrug resistance protein (MRP)] family of membrane export pumps. In inside-out membrane vesicles derived from insect cells or HEK293 cells, MRP4 catalyzed the time- and ATP-dependent uptake of prostaglandin E1 (PGE1) and PGE2. In contrast, MRP1, MRP2, MRP3, and MRP5 did not transport PGE1 or PGE2. The MRP4-mediated transport of PGE1 and PGE2 displayed saturation kinetics, with Km values of 2.1 and 3.4 μM, respectively. Further studies showed that PGF1α, PGF2α, PGA1, and thromboxane B2 were high-affinity inhibitors (and therefore presumably substrates) of MRP4. Furthermore, several nonsteroidal antiinflammatory drugs were potent inhibitors of MRP4 at concentrations that did not inhibit MRP1. In cells expressing the prostaglandin transporter PGT, the steady-state accumulation of PGE1 and PGE2 was reduced proportional to MRP4 expression. Inhibition of MRP4 by an MRP4-specific RNA interference construct or by indomethacin reversed this accumulation deficit. Together, these data suggest that MRP4 can release prostaglandins from cells, and that, in addition to inhibiting prostaglandin synthesis, some nonsteroidal antiinflammatory drugs might also act by inhibiting this release. PMID:12835412

  11. Novel contraceptive targets to inhibit ovulation: the prostaglandin E2 pathway

    Science.gov (United States)

    Duffy, Diane M.

    2015-01-01

    BACKGROUND Prostaglandin E2 (PGE2) is an essential intrafollicular regulator of ovulation. In contrast with the one-gene, one-protein concept for synthesis of peptide signaling molecules, production and metabolism of bioactive PGE2 requires controlled expression of many proteins, correct subcellular localization of enzymes, coordinated PGE2 synthesis and metabolism, and prostaglandin transport in and out of cells to facilitate PGE2 action and degradation. Elevated intrafollicular PGE2 is required for successful ovulation, so disruption of PGE2 synthesis, metabolism or transport may yield effective contraceptive strategies. METHODS This review summarizes case reports and studies on ovulation inhibition in women and macaques treated with cyclooxygenase inhibitors published from 1987 to 2014. These findings are discussed in the context of studies describing levels of mRNA, protein, and activity of prostaglandin synthesis and metabolic enzymes as well as prostaglandin transporters in ovarian cells. RESULTS The ovulatory surge of LH regulates the expression of each component of the PGE2 synthesis-metabolism-transport pathway within the ovulatory follicle. Data from primary ovarian cells and cancer cell lines suggest that enzymes and transporters can cooperate to optimize bioactive PGE2 levels. Elevated intrafollicular PGE2 mediates key ovulatory events including cumulus expansion, follicle rupture and oocyte release. Inhibitors of the prostaglandin-endoperoxide synthase 2 (PTGS2) enzyme (also known as cyclooxygenase-2 or COX2) reduce ovulation rates in women. Studies in macaques show that PTGS2 inhibitors can reduce the rates of cumulus expansion, oocyte release, follicle rupture, oocyte nuclear maturation and fertilization. A PTGS2 inhibitor reduced pregnancy rates in breeding macaques when administered to simulate emergency contraception. However, PTGS2 inhibition did not prevent pregnancy in monkeys when administered to simulate monthly contraceptive use. CONCLUSION

  12. Novel contraceptive targets to inhibit ovulation: the prostaglandin E2 pathway.

    Science.gov (United States)

    Duffy, Diane M

    2015-01-01

    Prostaglandin E2 (PGE2) is an essential intrafollicular regulator of ovulation. In contrast with the one-gene, one-protein concept for synthesis of peptide signaling molecules, production and metabolism of bioactive PGE2 requires controlled expression of many proteins, correct subcellular localization of enzymes, coordinated PGE2 synthesis and metabolism, and prostaglandin transport in and out of cells to facilitate PGE2 action and degradation. Elevated intrafollicular PGE2 is required for successful ovulation, so disruption of PGE2 synthesis, metabolism or transport may yield effective contraceptive strategies. This review summarizes case reports and studies on ovulation inhibition in women and macaques treated with cyclooxygenase inhibitors published from 1987 to 2014. These findings are discussed in the context of studies describing levels of mRNA, protein, and activity of prostaglandin synthesis and metabolic enzymes as well as prostaglandin transporters in ovarian cells. The ovulatory surge of LH regulates the expression of each component of the PGE2 synthesis-metabolism-transport pathway within the ovulatory follicle. Data from primary ovarian cells and cancer cell lines suggest that enzymes and transporters can cooperate to optimize bioactive PGE2 levels. Elevated intrafollicular PGE2 mediates key ovulatory events including cumulus expansion, follicle rupture and oocyte release. Inhibitors of the prostaglandin-endoperoxide synthase 2 (PTGS2) enzyme (also known as cyclooxygenase-2 or COX2) reduce ovulation rates in women. Studies in macaques show that PTGS2 inhibitors can reduce the rates of cumulus expansion, oocyte release, follicle rupture, oocyte nuclear maturation and fertilization. A PTGS2 inhibitor reduced pregnancy rates in breeding macaques when administered to simulate emergency contraception. However, PTGS2 inhibition did not prevent pregnancy in monkeys when administered to simulate monthly contraceptive use. PTGS2 inhibitors alone may be suitable

  13. 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......, respectively (P exercise in humans. These findings demonstrate an important synergistic role of NO and PG for skeletal muscle vasodilatation and hyperaemia during muscular contraction....... was quantified by near infrared spectroscopy and indocyanine green in six healthy humans during dynamic knee extension exercise with and without combined pharmacological inhibition of NO synthase (NOS) and PG by L-NAME and indomethacin, respectively. Microdialysis was applied to determine interstitial release...

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

    International Nuclear Information System (INIS)

    Wu, K.K.; Sanduja, R.; Tsai, A.L.; Ferhanoglu, B.; Loose-Mitchell, D.S.

    1991-01-01

    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-[ 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

  15. 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.

  16. Alpha-amylase inhibition kinetics by caulerpenyne

    Directory of Open Access Journals (Sweden)

    S. CENGIZ

    2010-03-01

    Full Text Available Many algae have important secretions which are generally used for defensive purposes. These secretions take attentions of a lot of researchers who are wondering if these metabolites can be used for medical researches or not. Among these metabolites, caulerpenyne (CYN which is the main metabolite of Caulerpa species, have had an important place in Caulerpa researches since the results related to its determined properties such as cytotoxic, antiviral, antiproliferative and apoptotic effects have been proven by many scientific reports. In the present study, the inhibitory effect of CYN isolated from C. prolifera on alpha-amylase was investigated. The inhibition experiments were done with CYN by spectrophotometric determination method. In order to evaluate the type of inhibition Lineweaver–Burk plot was produced. The results obtained from enzyme kinetic studies exhibited an un-competitive type of inhibition, which is characterized by the difference of Vmax and KM from those of the free enzyme, of alpha-amylase in the presence of CYN. The present study showed that Caulerpa species can be a potential target for producing diabetic drugs in the light of the results obtained for CYN.

  17. Inhibition of mouse osteoblast proliferation and prostaglandin E2 synthesis by Ulmus davidiana Planch (Ulmaceae).

    Science.gov (United States)

    Jin, Un-Ho; Suh, Seok-Jong; Park, Sang-Dong; Kim, Kap-Sung; Kwon, Dae Young; Kim, Cheorl-Ho

    2008-06-01

    Ulmus davidiana Planch (Ulmaceae) (UD) is a widely used Korean herbal medicine that has been used historically in anti-inflammatory and anticancer therapy. Since UD has been known to have anti-inflammatory and protective effects on damaged tissue, inflammation and bone among other functions, this study was undertaken to address whether the water extract of the bark of UD could modulate proliferation of mouse osteoblasts in vitro and to investigate its effect on cyclooxygenase-2 (COX-2), which converts arachidonic acid to prostaglandin E2 (PGE2). Mouse osteoblasts were tested in vitro for growth inhibition, proliferating cell nuclear antigen (PCNA) expression, and COX-2 activity and expression after treatment with UD extract. Its effects were compared with those of indomethacin (a nonselective COX inhibitor) and celecoxib (a selective COX-2 inhibitor). UD demonstrated a strong growth inhibition in tested mouse osteoblasts. The IC50s were 10microg/ml for UD, 6microM for celecoxib and 42microM for indomethacin. UD, as well as celecoxib and indomethacin, suppressed PCNA expression and PGE2 synthesis in osteoblasts. UD inhibited COX-2 expression, whereas celecoxib inhibited COX-2 activity directly. UD selectively and effectively inhibits osteoblasts cell growth in vitro. Inhibition of PGE2 synthesis via suppression of COX-2 expression may be responsible for its anti-inflammatory activity.

  18. Prostaglandin A1 metabolism and inhibition of cyclic AMP extrusion by avian erythrocytes

    International Nuclear Information System (INIS)

    Heasley, L.E.; Brunton, L.L.

    1985-01-01

    Prostaglandins (PG) inhibit active cyclic AMP export from pigeon red cells, PGA1 and PGA2 most potently. To probe the mechanism of this action of PGA1, the authors have studied the interaction of [ 3 H]PGA1 with suspensions of pigeon red cells. The interaction of PGA1 with pigeon red cells is a multistep process of uptake, metabolism, and secretion. [ 3 H] PGA1 rapidly enters red cells and is promptly metabolized to a compound(s) that remains in the aqueous layer after ethylacetate extraction. The glutathione-depleting agent, diamide, inhibits formation of the PGA1 metabolite. The red cells secrete the polar metabolite of PGA1 by a saturable mechanism that lowered temperatures inhibit. Because uptake and metabolism progress with much greater rates than metabolite secretion, red cells transiently concentrate the polar compound intracellularly. Onset and reversal of inhibition of cyclic AMP export by PGA1 coincide with accumulation and secretion of PGA1 metabolite, suggesting that the polar metabolite acts at an intracellular site to inhibit cyclic AMP efflux

  19. 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

  20. Inhibition of prostaglandin D₂ production by trihydroxy fatty acids isolated from Ulmus davidiana var. japonica.

    Science.gov (United States)

    Choi, Hyun Gyu; Park, Yu Mi; Lu, Yue; Chang, Hyeun Wook; Na, Minkyun; Lee, Seung Ho

    2013-09-01

    The stem and root barks of Ulmus davidiana var. japonica (Ulmaceae) have been used to treat inflammatory diseases including mastitis, rhinitis, sinusitis, and enteritis. In an ongoing study focused on the discovery of natural anti-inflammatory compounds from natural products, a methanol extract of the stem and root barks of U. davidiana var. japonica showed anti-inflammatory activities. Activity-guided fractionation of the methanol extract yielded a new trihydroxy fatty acid, 9,12,13-trihydroxyoctadeca-10(Z),15(Z)-dienoic acid (1), and a known compound, pinellic acid (2). These two trihydroxy fatty acids 1 and 2 inhibited prostaglandin D₂ production with IC₅₀ values of 25.8 and 40.8 μM, respectively. These results suggest that 9,12,13-trihydroxyoctadeca-10(Z),15(Z)-dienoic acid (1) and pinellic acid (2) are among the anti-inflammatory principles in this medicinal plant. Copyright © 2012 John Wiley & Sons, Ltd.

  1. Export of cyclic AMP by avian red cells and inhibition by prostaglandin A1

    International Nuclear Information System (INIS)

    Heasley, L.E.

    1985-01-01

    The mechanism by which PGA 1 inhibits cAMP export by avian red cells was studied, to provide details on the molecular mechanism of a prostaglandin action and on the process of cAMP export itself. The interaction of PGA 1 with pigeon red cells is a multi-step process of uptake, metabolism and secretion. [ 3 H]PGA rapidly enters red cells and is promptly metabolized (V/sub max/ ≥ 1 nmol/min/10 7 cells) to a compound (5) that remains in the aqueous layer after ethyl acetate extraction. Chromatographic analyses, amino acid content and fast atom bombardment mass spectrometry reveal that the polar metabolite is conjugated with glutathione (PGA 1 -GSH) at C-11 via a thioether bond and is largely (80%) reduced to the C-9 hydroxyl derivative

  2. Effects of prostaglandin F2alpha treatment on the behavior of pseudopregnant pigs in an extensive environment.

    Science.gov (United States)

    Gilbert, C L; Murfitt, P J; Boulton, M I; Pain, J; Burne, T H

    2000-05-01

    In seminatural environments, prepartum sows leave the herd and construct a maternal nest (a dug out hollow lined with vegetation) prior to the birth of their piglets. The endocrine drives motivating this behavior are not understood, but may involve prostaglandin (PG) F2alpha. This study examined the effect of PGF2alpha treatment on the behavior of pseudopregnant gifts housed in a large enclosure. Pseudopregnancy was induced using 5 mg/ml estradiol valerate/day im from days 11 to 15 of the estrous cycle (first day of estrus = day 0). The gifts' behavior was recorded on a control day, during which no treatment was given, and a test day (= 45.9 +/- 0.42 days of pseudopregnancy) when gilts received either 15 mg PGF2alpha (dinoprost: Lutalyse, Upjohn, Crawley, UK, n = 11) or 0.9% saline (n = 10) im at 11.00 h. PGF2alpha-treated gilts traveled further and were more frequently >10 m from the nearest pig than saline-treated animals. In the hour following injection, PGF2alpha-treated animals also showed increased frequencies of rooting and pawing the ground and stood for longer than saline-treated animals. However, gathering and carrying nest materials were not increased. These results suggest that PGF2alpha, given as a single dose to extensively housed gilts, initiated many, but not all, of the behaviors characteristic of prepartum nest building. The dose and duration of PGF2alpha treatment may have limited the observed behaviors. In addition, environmental feedback is likely to affect the degree to which some nest building behaviors are expressed.

  3. Canine placental prostaglandin E2 synthase: expression, localization, and biological functions in providing substrates for prepartum PGF2alpha synthesis.

    Science.gov (United States)

    Gram, Aykut; Fox, Barbara; Büchler, Urs; Boos, Alois; Hoffmann, Bernd; Kowalewski, Mariusz P

    2014-12-01

    The prepartum output of PGF2alpha in the bitch is associated with increased placental PGE2-synthase (PTGES) mRNA levels. Contrasting with this is a decreased expression of PGF2alpha-synthase (PGFS/AKR1C3) in uteroplacental compartments during prepartum luteolysis, suggesting an involvement of alternative synthetic pathways in PGF2alpha synthesis, for example, conversion of PGE2 to PGF2alpha. However, because the expression and possible functions of the respective PTGES proteins remained unknown, no further conclusion could be drawn. Therefore, a canine-specific PTGES antibody was generated and used to investigate the expression, cellular localization, and biochemical activities of canine uteroplacental PTGES throughout pregnancy and at prepartum luteolysis. Additionally, the biochemical activities of these tissues involved in the conversion of PGE2 to PGF2alpha were investigated. The endometrial PTGES was localized in the uterine surface epithelium at preimplantation and in superficial and deep uterine glands, endothelial cells, and myometrium throughout pregnancy and at parturition. Placental signals were mostly in the trophoblast. The biochemical properties of recombinant PTGES protein were confirmed. Additionally, expression of two PGE2-receptors, PTGER2/EP2 and PTGER4/EP4, revealed their decreasing expression during luteolysis. In contrast, the uteroplacental expression of prostaglandin transporter (PGT) was strongly elevated prior to parturition. These localization patterns resembled that of PTGES. The increased expression of PTGES and PGT at parturition, together with the accompanying decreased levels of PGE2-receptors and the capability of canine uterine and placental homogenates to take part in the conversion of PGE2 to PGF2alpha, as found in this study, suggest that PGE2 could be used locally as a substrate for prepartum PGF2alpha synthesis in the dog. © 2014 by the Society for the Study of Reproduction, Inc.

  4. Inhibition by prostaglandin E1 of gastric secretion in the dog

    Science.gov (United States)

    Nezamis, James E.; Robert, André; Stowe, David F.

    1971-01-01

    1. The effect of prostaglandin E1 (PGE1) on gastric secretion was studied in dogs equipped with gastric fundic pouches, either innervated (Pavlov) or denervated (Heidenhain). 2. PGE1 inhibited gastric secretion (volume, acid concentration, acid output, pepsin output) when given either by constant intravenous infusion or by single intravenous injection. The degree of inhibition was dose dependent. 3. The antisecretory effect of PGE1 was demonstrated against gastric stimulants which operate through different mechanisms. Thus, PGE1 counteracted the secretogogue effect of: (a) histamine dihydrochloride; the ED50 was 0·5-1·0 μg/kg. min for a submaximal dose, and 1·0-1·5 μg/kg. min for a maximal dose; (b) pentagastrin; the ED50 was around 0·25 μg/kg. min; (c) food; the ED50 was 0·5 to 0·75 μg/kg. min; (d) 2-deoxyglucose; the ED50 was less than 0·1 μg/kg. min. 4. Although in some experiments, nausea and vomiting were observed during administration of PGE1, the antisecretory property of the substance is not related to a vomiting reflex, since (a) an antiemetic, such as atropine, prevented vomiting without interfering with the effect of PGE1, and (b) profuse vomiting elicited by apomorphine did not reduce gastric secretion stimulated by either histamine or pentagastrin. 5. The mechanism by which PGE1 inhibits gastric secretion is unknown. Studies by others have shown that the compound reduces gastric mucosal blood flow, inhibits acid formation from gastric mucosa when applied in vitro and may change the rate of formation of gastric cyclic AMP. It is likely that PGE1 interferes with biochemical processes, within parietal and chief cells, which lead to elaboration of gastric juice. 6. Unlike most gastric inhibitors, PGE1 appears to act as a protective shield against most, if not all, gastric stimulants. Since prostaglandins of the E series are naturally occurring substances and are normally present in the stomach, they may play a role in the regulation of gastric

  5. Transcriptomic and bioinformatics analysis of the early time-course of the response to prostaglandin F2 alpha in the bovine corpus luteum

    Science.gov (United States)

    RNA expression analysis was performed on the corpus luteum tissue at five time points after prostaglandin F2 alpha treatment of midcycle cows using an Affymetrix Bovine Gene v1 Array. The normalized linear microarray data was uploaded to the NCBI GEO repository (GSE94069). Subsequent statistical ana...

  6. 15-deoxy prostaglandin J2, the nonenzymatic metabolite of prostaglandin D2, induces apoptosis in keratinocytes of human hair follicles: a possible explanation for prostaglandin D2-mediated inhibition of hair growth.

    Science.gov (United States)

    Joo, Hyun Woo; Kang, Yoo Ri; Kwack, Mi Hee; Sung, Young Kwan

    2016-07-01

    Recent studies have shown that prostaglandin D2 (PGD2) and its nonenzymatic metabolite, 15-deoxy-Δ(12,14)-prostaglandin J2 (15-dPGJ2), inhibit in vitro growth of explanted human hair follicles and inhibit hair growth in mice through the GPR44 (DP2). However, the underlying mechanism is still unclear. In this study, we first investigated the expression of DP2 in human hair follicles and in cultured follicular cells. We found that DP2 is strongly expressed in the outer root sheath (ORS) cells and weakly expressed in the dermal papilla (DP) cells. We observed slight growth stimulation when ORS and DP cells were treated with PGD2. We also observed slight growth stimulation when DP and ORS cells were treated with low concentrations (0.5 and 1 μM) of 15-dPGJ2. However, 5 μM 15-dPGJ2 inhibited the viability and caused apoptosis of both cell types. Exposure of cultured human hair follicles to 15-dPGJ2 resulted in significant apoptosis in follicular keratinocytes. Altogether, our data provide an evidence that 15-dPGJ2 promotes apoptosis in follicular keratinocytes and provide rationale for developing remedies for the prevention and treatment of hair loss based on DP2 antagonism.

  7. Prostaglandin F2 alpha metabolite and progesterone profiles in post-partum cows with retained foetal membranes.

    Science.gov (United States)

    Bekana, M; Odensvik, K; Kindahl, H

    1996-01-01

    Post-partum prostaglandin release and resumption of cyclical ovarian activities were studied in 11 Swedish dairy cows with retained foetal membranes (RFM), leaving the RFM untreated. The main PGF2 alpha metabolite, 15-ketodihydro-PGF2 alpha, was measured in blood plasma collected twice daily during the first 50-60 days after delivery. Progesterone was monitored from all morning samples to evaluate the resumption of ovarian activity. The plasma levels of 15-ketodihydro-PGF2 alpha were arbitrarily considered to be significantly elevated between 6-24 days when they exceeded the mean basal value + 2 standard deviations. Comparison between this duration in days of the post-partum PGF2 alpha release and the time required for the completion of uterine involution, placental shedding and last day of post-partum clinical signs showed no significant relations. However, prior to a final decrease below a line of significance of 233-590 pmol/l, pronounced sustained and pulsatile release of PGF2 alpha occurred in relation to the increased frequency of the bacteriological findings. These additional periods of PGF2 alpha release were described as the "total" duration of post-partum release, and were found to be positively correlated with the time required for uterine involution from the stand point of rectal palpation (p < 0.05), while a tendency towards a positive relationship existed for the last day post-partum of clinical signs (p = 0.11). Progesterone analysis revealed resumption of ovarian activity and the first ovulation occurred between 19-29 days in 70% of the cows. The levels of the PGF2 alpha metabolite were again high at the time of luteolysis, thus terminating the luteal phase in the ovulating animals. Thus, it is seen that non-removal of the RFM or the resultant intrauterine infection do not prolong the duration of the immediate post-partum release of PGF2 alpha as compared to normal animals. However, a second release is associated with the increased frequency of

  8. 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).

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

    Directory of Open Access Journals (Sweden)

    Barbosa Joel Antonio

    1998-01-01

    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.

  10. 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...... blind, cross over design. In each subject misoprostol or placebo was instilled in randomised order into the stomach, which was subsequently perfused with isotonic mannitol. Misoprostol significantly decreased basal as well as acid stimulated output of PGE2 and TXB2, without affecting output of LTB4....... 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...

  11. Dual inhibition of nitric oxide and prostaglandin E-2 production by polysubstituted 2-aminopyrimidines

    Czech Academy of Sciences Publication Activity Database

    Zídek, Z.; Kverka, Miloslav; Dusilová, Adéla; Kmoníčková, E.; Jansa, P.

    2016-01-01

    Roč. 57, July 1 (2016), s. 48-56 ISSN 1089-8603 Institutional support: RVO:61388971 Keywords : Pyrimidines * Nitric oxide * Prostaglandin E-2 Subject RIV: EE - Microbiology, Virology Impact factor: 4.181, year: 2016

  12. Prostaglandin D2 inhibits hair growth and is elevated in bald scalp of men with androgenetic alopecia.

    Science.gov (United States)

    Garza, Luis A; Liu, Yaping; Yang, Zaixin; Alagesan, Brinda; Lawson, John A; Norberg, Scott M; Loy, Dorothy E; Zhao, Tailun; Blatt, Hanz B; Stanton, David C; Carrasco, Lee; Ahluwalia, Gurpreet; Fischer, Susan M; FitzGerald, Garret A; Cotsarelis, George

    2012-03-21

    Testosterone is necessary for the development of male pattern baldness, known as androgenetic alopecia (AGA); yet, the mechanisms for decreased hair growth in this disorder are unclear. We show that prostaglandin D(2) synthase (PTGDS) is elevated at the mRNA and protein levels in bald scalp compared to haired scalp of men with AGA. The product of PTGDS enzyme activity, prostaglandin D(2) (PGD(2)), is similarly elevated in bald scalp. During normal follicle cycling in mice, Ptgds and PGD(2) levels increase immediately preceding the regression phase, suggesting an inhibitory effect on hair growth. We show that PGD(2) inhibits hair growth in explanted human hair follicles and when applied topically to mice. Hair growth inhibition requires the PGD(2) receptor G protein (heterotrimeric guanine nucleotide)-coupled receptor 44 (GPR44), but not the PGD(2) receptor 1 (PTGDR). Furthermore, we find that a transgenic mouse, K14-Ptgs2, which targets prostaglandin-endoperoxide synthase 2 expression to the skin, demonstrates elevated levels of PGD(2) in the skin and develops alopecia, follicular miniaturization, and sebaceous gland hyperplasia, which are all hallmarks of human AGA. These results define PGD(2) as an inhibitor of hair growth in AGA and suggest the PGD(2)-GPR44 pathway as a potential target for treatment.

  13. Prostaglandin synthesis and catabolism in the gastric mucosa: studies in normal rabbits and rabbits immunized with prostaglandin E2

    International Nuclear Information System (INIS)

    Redfern, J.S.

    1988-01-01

    Antral and fundic mucosal homogenates obtained from prostaglandin E2-immunized rabbits converted 14C-arachidonic acid to prostaglandin E2, 6-keto prostaglandin F1 alpha, prostaglandin F2 alpha, and prostaglandin D2. Percentage conversion of 14C-arachidonic acid to these prostaglandin products was not significantly different in prostaglandin E2-immunized rabbits compared with control rabbits (thyroglobulin-immunized and unimmunized rabbits combined). Synthesis of 6-keto prostaglandin F1 alpha, prostaglandin E2 and 13,14-dihydro 15-keto prostaglandin E2 from endogenous arachidonic acid after vortex mixing fundic mucosal homogenates was similar in prostaglandin E2 immunized rabbits and control rabbits. Both in prostaglandin E2-immunized rabbits and controls, 3H-prostaglandin E2 was catabolized extensively by the fundic mucosa, whereas 3H-6-keto prostaglandin F1 alpha, 3H-prostaglandin F2 alpha, and 3H-prostaglandin D2 were not catabolized to any appreciable extent. The rate of catabolism of PGs was not significantly different in prostaglandin E2-immunized rabbits and control rabbits, with the exception of prostaglandin F2 alpha which was catabolized slightly more rapidly in prostaglandin E2-immunized rabbits. These results indicate that development of gastric ulcers in prostaglandin E2-immunized rabbits is not associated with an alteration in the capacity of the gastric mucosa to synthesize or catabolize prostaglandins

  14. The human multidrug resistance protein MRP4 functions as a prostaglandin efflux transporter and is inhibited by nonsteroidal antiinflammatory drugs

    NARCIS (Netherlands)

    Reid, Glen; Wielinga, Peter; Zelcer, Noam; van der Heijden, Ingrid; Kuil, Annemieke; de Haas, Marcel; Wijnholds, Jan; Borst, Piet

    2003-01-01

    Prostaglandins are involved in a wide variety of physiological and pathophysiological processes, but the mechanism of prostaglandin release from cells is not completely understood. Although poorly membrane permeable, prostaglandins are believed to exit cells by passive diffusion. We have

  15. 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......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......, respectively (P important synergistic role of NO and PG for skeletal muscle vasodilatation and hyperaemia during muscular contraction....

  16. Study of molecular mechanism of Prostaglandin E1 in inhibiting coronary heart disease.

    Science.gov (United States)

    Liu, H J; Ma, J W; Qiao, Z Y; Xu, B

    2013-12-01

    Prostaglandin E1 has been used clinically for improving heart diseases. In this study, we examined the effect of Prostaglandin E1 on blood lipid levels, heart protein and genes expression in coronary heart disease (CHD) rats. Female rats were fed either a control diet or hypercholesterolemic diet for 14 weeks. The feeding of a hypercholesterolemic diet (HCD) increased the serum TC, TG, and LDL-c levels, decreased the serum HDL-c, E2, P, FSH, LH and PRL levels in CHD rats. In addition, The feeding of a HCD diet markedly increased the content of serum TXA2, TXB2, and decreased the content of serum PGI2, and PGI2/TXA2, 6-Keto PGF1a. Furthermore, the feeding of a hypercholesterolemic diet markedly increased expression levels of myocardium Fas and Caspase-3 protein and mRNA levels, vascular endothelial growth factor and basic fibroblast growth factor mRNA, and decreased RyR2 mRNA in CHD rats. The feeding of Prostaglandin E1 for 14 weeks significantly reversed these abnormal biochemical indexes in rats. These findings suggest that Prostaglandin E1 play a obvious heart protective effect. The mechanisms may be related to restraining the excessive activation of Fas and Caspase-3 protein and modulating some gene expressions associated with CHD.

  17. Dual inhibition of nitric oxide and prostaglandin E2 production by polysubstituted 2-aminopyrimidines

    Czech Academy of Sciences Publication Activity Database

    Zídek, Zdeněk; Kverka, Miloslav; Dusilová, Adéla; Kmoníčková, Eva; Jansa, Petr

    2016-01-01

    Roč. 57, jul (2016), s. 48-56 ISSN 1089-8603 R&D Projects: GA ČR(CZ) GAP303/12/0172 Institutional support: RVO:68378041 ; RVO:61388963 Keywords : pyrimidines * nitric oxide * prostaglandin E-2 Subject RIV: FR - Pharmacology ; Medidal Chemistry; CC - Organic Chemistry (UOCHB-X) Impact factor: 4.181, year: 2016

  18. Evaluation of the possible role of prostaglandin F(2 alpha) in laminitis induced in horses by nasogastric administration of black walnut heartwood extract.

    Science.gov (United States)

    Noschka, Erik; Moore, James N; Peroni, John F; Lewis, Tristan H; Lewis, Stephen J; Robertson, Tom P

    2010-02-01

    To provide insights into the role of prostaglandin F(2 alpha) (PGF(2 alpha)) in the developmental stages of laminitis induced in horses by ingestion of black walnut heartwood extract (BWHE). 10 adult mixed-breed horses. Horses were separated into 2 groups and were euthanatized at 12 hours after placebo (water) administration (control horses) or after BWHE administration and development of Obel grade 1 laminitis. Blood samples were obtained to determine plasma PGF(2 alpha) concentrations hourly for the first 4 hours and subsequently every 2 hours after substance administration. Laminar arteries and veins were isolated, and responses to increasing concentrations of PGF(2 alpha) were measured before and after preincubation of blood vessels with prostanoid and thromboxane receptor antagonists SQ 29,548, SC-19220, and AH 6809. Plasma PGF(2 alpha) concentrations increased in horses given BWHE; the WBC count decreased concurrently. In control horses, PGF(2 alpha) was a potent contractile agonist for laminar veins but not for laminar arteries. In horses given BWHE, PGF(2 alpha) was similarly selective for laminar veins; however, the magnitude of PGF(2 alpha)-induced venoconstriction was less than that in control horses. After preincubation with SQ 29,548, laminar veins from control horses responded to PGF(2 alpha) with a small degree of dilation, whereas laminar veins from horses given BWHE did not. PGF(2 alpha) may play a role in the inflammatory and vascular dysfunction associated with the prodromal stages of laminitis. Prostanoids such as PGF(2 alpha) may be viable targets for the prevention of acute laminitis in horses.

  19. Cortical alpha oscillations as a tool for auditory selective inhibition

    Directory of Open Access Journals (Sweden)

    Antje eStrauß

    2014-05-01

    Full Text Available Listening to speech is often demanding because of signal degradations and the presence of distracting sounds (i.e., noise. The question how the brain achieves the task of extracting only relevant information from the mixture of sounds reaching the ear (i.e., cocktail party problem is still open. In analogy to recent findings in vision, we propose cortical alpha (~10 Hz oscillations measurable using M/EEG as a pivotal mechanism to selectively inhibit the processing of noise to improve auditory selective attention to task-relevant signals. We review initial evidence of enhanced alpha activity in selective listening tasks, suggesting a significant role of alpha-modulated noise suppression in speech. We discuss the importance of dissociating between noise interference in the auditory periphery (i.e., energetic masking and noise interference with more central cognitive aspects of speech processing (i.e., informational masking. Finally, we point out the adverse effects of age-related hearing loss and/or cognitive decline on auditory selective inhibition. With this perspective article, we set the stage for future studies on the inhibitory role of alpha oscillations for speech processing in challenging listening situations.

  20. Inhibition of platelet aggregation by prostaglandin E1 (PGE1) in diabetic patients during therapy with clopidogrel and aspirin.

    Science.gov (United States)

    Kreutz, Rolf P; Nystrom, Perry; Kreutz, Yvonne; Miao, Jia; Kovacs, Richard; Desta, Zeruesenay; Flockhart, David A; Jin, Yan

    2013-01-01

    Diabetes mellitus (DM) is associated with increased platelet activation and reduced platelet inhibition by clopidogrel. Prostaglandin E1 (PGE1) stimulates adenyl cyclase activity in platelets and increases cyclic AMP concentrations, which inhibit Ca(2+)release and platelet aggregation induced by P2Y1 receptor activation. PGE1 is included in the VerifyNow P2Y12 assay to suppress P2Y1 induced platelet aggregation. We hypothesized that diabetes mellitus may be associated with altered response to PGE1 in subjects treated with clopidogrel. Subjects with established coronary artery disease who were taking clopidogrel 75 mg daily and aspirin for >14 days were enrolled (n = 96). Diabetic (n = 34) were compared with non-diabetic subjects (n = 62). VerifyNow P2Y12 assay and light transmittance aggregometry (LTA) were performed using ADP as agonist with and without addition of PGE1. Genomic DNA was genotyped for common cytochrome P450 (CYP) 2C19 variants using Taqman assays. Residual on-treatment platelet aggregation induced by 20 µM ADP was not significantly different between subjects with and without DM. Addition of 22 nM and 88 nM PGE1 to 20 µM ADP resulted in a significant reduction of maximal platelet aggregation (MPA). Residual LTA platelet aggregation with PGE1 and VerifyNow P2Y12 platelet reactivity were significantly higher in subjects with DM than those without DM and in carriers of CYP 2C19*2 polymorphism. We conclude that an impaired inhibitory response to PGE1 may contribute to the high platelet reactivity phenotype in subjects with DM treated with clopidogrel. Addition of PGE1 to ADP agonist platelet assays may identify subjects with blunted inhibitory response to prostaglandins and result in a higher proportion of subjects with DM being classified as non-responders.

  1. Transcriptomic and bioinformatics analysis of the early time-course of the response to prostaglandin F2 alpha in the bovine corpus luteum

    Directory of Open Access Journals (Sweden)

    Heather Talbott

    2017-10-01

    Full Text Available RNA expression analysis was performed on the corpus luteum tissue at five time points after prostaglandin F2 alpha treatment of midcycle cows using an Affymetrix Bovine Gene v1 Array. The normalized linear microarray data was uploaded to the NCBI GEO repository (GSE94069. Subsequent statistical analysis determined differentially expressed transcripts ± 1.5-fold change from saline control with P ≤ 0.05. Gene ontology of differentially expressed transcripts was annotated by DAVID and Panther. Physiological characteristics of the study animals are presented in a figure. Bioinformatic analysis by Ingenuity Pathway Analysis was curated, compiled, and presented in tables. A dataset comparison with similar microarray analyses was performed and bioinformatics analysis by Ingenuity Pathway Analysis, DAVID, Panther, and String of differentially expressed genes from each dataset as well as the differentially expressed genes common to all three datasets were curated, compiled, and presented in tables. Finally, a table comparing four bioinformatics tools’ predictions of functions associated with genes common to all three datasets is presented. These data have been further analyzed and interpreted in the companion article “Early transcriptome responses of the bovine mid-cycle corpus luteum to prostaglandin F2 alpha includes cytokine signaling” [1].

  2. An indomethacin analogue, N-(4-chlorobenzoyl)-melatonin, is a selective inhibitor of aldo-keto reductase 1C3 (type 2 3alpha-HSD, type 5 17beta-HSD, and prostaglandin F synthase), a potential target for the treatment of hormone dependent and hormone independent malignancies.

    Science.gov (United States)

    Byrns, Michael C; Steckelbroeck, Stephan; Penning, Trevor M

    2008-01-15

    Aldo-keto reductase (AKR) 1C3 (type 2 3alpha-HSD, type 5 17beta-HSD, and prostaglandin F synthase) regulates ligand access to steroid hormone and prostaglandin receptors and may stimulate proliferation of prostate and breast cancer cells. NSAIDs are known inhibitors of AKR1C enzymes. An NSAID analogue that inhibits AKR1C3 but is inactive against the cyclooxygenases and the other AKR1C family members would provide an important tool to examine the role of AKR1C3 in proliferative signaling. We tested NSAIDs and NSAID analogues for inhibition of the reduction of 9,10-phenanthrenequinone (PQ) catalyzed by AKR1C3 and the closely related isoforms AKR1C1 and AKR1C2. Two of the compounds initially screened, indomethacin and its methyl ester, were specific for AKR1C3 versus the other AKR1C isoforms. Based on these results and the crystal structure of AKR1C3, we predicted that N-(4-chlorobenzoyl)-melatonin (CBM), an indomethacin analogue that does not inhibit the cyclooxygenases, would selectively inhibit AKR1C3. CBM inhibited the reduction of PQ by AKR1C3, but did not significantly inhibit AKR1C1 or AKR1C2. Indomethacin and CBM also inhibited the AKR1C3-catalyzed reduction of Delta(4)-androstene-3,17-dione but did not significantly inhibit the reduction of steroid hormones catalyzed by AKR1C1 or AKR1C2. The pattern of inhibition of AKR1C3 by indomethacin and CBM was uncompetitive versus PQ, but competitive versus Delta(4)-androstene-3,17-dione, indicating that two different inhibitory complexes form during the ordered bi bi reactions. The identification of CBM as a specific inhibitor of AKR1C3 will aid the investigation of its roles in steroid hormone and prostaglandin signaling and the resultant effects on cancer development.

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

    Directory of Open Access Journals (Sweden)

    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

  4. Dienogest inhibits aromatase and cyclooxygenase-2 expression and prostaglandin E₂ production in human endometriotic stromal cells in spheroid culture.

    Science.gov (United States)

    Yamanaka, Kaoruko; Xu, Bing; Suganuma, Izumi; Kusuki, Izumi; Mita, Shizuka; Shimizu, Yutaka; Mizuguchi, Kiyoshi; Kitawaki, Jo

    2012-02-01

    To determine the effect of dienogest (DNG) on the expression of aromatase and cyclooxygenase-2 (COX-2) and the production of prostaglandin E(2) (PGE(2)) in human endometriotic stromal cells (ESCs). Experimental study in vitro. University hospital. Seventeen patients with ovarian endometrioma. ESCs from chocolate cyst linings of ovaries were treated with DNG. Expression of aromatase and COX-2 evaluated in spheroid cultures of human ESCs by real-time quantitative polymerase chain-reaction and immunocytochemistry, production of PGE(2) quantified by enzyme-linked immunosorbent assay (ELISA), and nuclear factor kappa B (NF-κB) DNA-binding examined by ELISA and immunocytochemistry. The pharmaceutical actions of DNG on the expression of aromatase and COX-2 and the production of PGE(2) were examined using spheroid cultures of human ESCs. More aromatase, COX-2, and PGE(2) were expressed in spheroid cultures than in conventional ESCs monolayers. In the spheroid cultures, DNG (10(-7) M) and progesterone (10(-7) M) inhibited the expression of aromatase, COX-2, and PGE(2). DNG also inhibited NF-κB DNA-binding activity and reduced the immunocytochemical protein expression of aromatase, COX-2, and NF-κB p50 nuclear localization. Because DNG inhibits aromatase and COX-2 expression as well as PGE(2) production in ESCs, these pharmacologic features might contribute to a therapeutic effect of DNG on endometriosis. Copyright © 2012 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  5. A chemotactic role for prostaglandins released from polymorphonuclear leucocytes during phagocytosis.

    Science.gov (United States)

    Higgs, G A; McCall, E; Youlten, L J

    1975-01-01

    1. Prostaglandin E1 is chemotactic at concentrations down to 10 ng/ml for rabbit polymorphonuclear (PMN) leucocytes. Prostaglandins E2 and F2alpha have little or no chemotactic effect at concentrations up to 10 mug/ml. 2. Washed PMN leucocytes produced a chemotactic agent during phagocytosis, but not in the presence of indomethacin (28 muM). 3. Phagocytosing PMN leucocytes produce up to ten times as much prostaglandin as do resting cells. Some of this is prostaglandin E1 as judged by thin layer chromatography and differential bioassay. This prostaglandin production by PMN leucocytes is abolished by indomethacin (28 muM). 4. Ultrasonicated suspensions of PMN leucocytes produced prostaglandin from arachidonic aicd. This synthesis is inhibited by indomethacin. 5. Homogenates of PMN leucocytes which have been pre-incubated withe bacteria for 30 min show more prostaglandin synthetase activity than homogenates from PMN leucocytes which have not been exposed to bacteria. 6. It is concluded that in some forms of inflammation, prostaglandin E1 may play a controlling role in cellular migration. 7. PMN leucocytes may contribute to the generation of prostaglandins found in some inflammatory lesions. PMID:1148497

  6. Inhibition of HIF-2.alpha. heterodimerization with HIF1.beta. (ARNT)

    Energy Technology Data Exchange (ETDEWEB)

    Bruick, Richard K.; Caldwell, Charles G.; Frantz, Doug E.; Gardner, Kevin H.; MacMillan, John B.; Scheuermann, Thomas H.; Tambar, Uttam K.

    2017-09-12

    Provided is a method of inhibiting heterodimerization of HIF-2.alpha. to HIF1.beta. (ARNT) comprising binding certain small molecules to the HIF-2.alpha. PAS-B domain cavity but not to HIF1.alpha. and inhibiting HIF-2.alpha. heterodimerization to HIF1.beta. (ARNT) but not inhibiting HIF1.alpha. heterodimerization to HIF1.beta. (ARNT). Those certain small molecules are also referenced synonymously as HIF2-HDI and HIF2.alpha. heterodimerization inhibitors and also simply as certain small molecules.

  7. Echinacea Species and Alkamides Inhibit Prostaglandin E2 Production in RAW264.7 Mouse Macrophage Cells

    Science.gov (United States)

    LaLone, Carlie A.; Hammer, Kimberly D. P.; Wu, Lankun; Bae, Jaehoon; Leyva, Norma; Liu, Yi; Solco, Avery K. S.; Kraus, George A.; Murphy, Patricia A.; Wurtele, Eve S.; kim, Ok-Kyung; Seo, Kwon; Widrlechner, Mark P.; Birt, Diane F.

    2008-01-01

    Inhibition of prostaglandin E2 (PGE2) production in lipopolysaccharide-stimulated RAW264.7 mouse macrophage cells was assessed with an enzyme immunoassay following treatments with Echinacea extracts or synthesized alkamides. Results indicated that ethanol extracts diluted in media to a concentration of 15 μg/mL from E. angustifolia, E. pallida, E. simulata, and E. sanguinea significantly inhibited PGE2 production. In further studies, PGE2 production was significantly reduced by all synthesized alkamides assayed at 50 μM, by Bauer alkamides 8, 12A analogue, and 14, Chen alkamide 2, and Chen alkamide 2 analogue at 25 μM and by Bauer alkamide 14 at 10 μM. Cytotoxicity did not play a role in the noted reduction of PGE2 production in either the Echinacea extracts or synthesized alkamides. High-performance liquid chromatography analysis identified individual alkamides present at concentrations below 2.8 μM in the extracts from the six Echinacea species (15 μg/mL crude extract). Because active extracts contained Echinacea in a synergistic or additive manner. PMID:17696440

  8. Echinacea species and alkamides inhibit prostaglandin E(2) production in RAW264.7 mouse macrophage cells.

    Science.gov (United States)

    LaLone, Carlie A; Hammer, Kimberly D P; Wu, Lankun; Bae, Jaehoon; Leyva, Norma; Liu, Yi; Solco, Avery K S; Kraus, George A; Murphy, Patricia A; Wurtele, Eve S; Kim, Ok-Kyung; Seo, Kwon Ii; Widrlechner, Mark P; Birt, Diane F

    2007-09-05

    Inhibition of prostaglandin E(2) (PGE(2)) production in lipopolysaccharide-stimulated RAW264.7 mouse macrophage cells was assessed with an enzyme immunoassay following treatments with Echinacea extracts or synthesized alkamides. Results indicated that ethanol extracts diluted in media to a concentration of 15 microg/mL from E. angustifolia, E. pallida, E. simulata, and E. sanguinea significantly inhibited PGE2 production. In further studies, PGE2 production was significantly reduced by all synthesized alkamides assayed at 50 microM, by Bauer alkamides 8, 12A analogue, and 14, Chen alkamide 2, and Chen alkamide 2 analogue at 25 microM and by Bauer alkamide 14 at 10 microM. Cytotoxicity did not play a role in the noted reduction of PGE2 production in either the Echinacea extracts or synthesized alkamides. High-performance liquid chromatography analysis identified individual alkamides present at concentrations below 2.8 microM in the extracts from the six Echinacea species (15 microg/mL crude extract). Because active extracts contained Echinacea in a synergistic or additive manner.

  9. Prostaglandin E 2 (PgE 2 ) Inhibition By Crude Extracts Of Selected ...

    African Journals Online (AJOL)

    This study was undertaken to assess anti-inflammatory activity of crude extracts of Cassine transvaalensis Burtt-Davy, Clerodendrum uncinatum Schinz and Commiphora glandulosa Schinz using COX inhibition assay. Water extract of C. transvaalensis root bark (125mg/ml) exhibited a (90%) PGE2 inhibition in ...

  10. Differential effect of prostaglandins E1 and E2 on lipopolysaccharide-induced adhesion molecule expression on human monocytes.

    Science.gov (United States)

    Takahashi, Hideo K; Iwagaki, Hiromi; Tamura, Ryuji; Katsuno, Goutaro; Xue, Dong; Sugita, Sachi; Mori, Shuji; Yoshino, Tadashi; Tanaka, Noriaki; Nishibori, Masahiro

    2005-04-11

    The effect of prostaglandins E1 and E2 on the 1 ng/ml lipopolysaccharide-induced expression of intercellular adhesion molecule (ICAM)-1, B7.1, B7.2, CD40 and CD40 ligand (CD40L) on monocytes was examined. Prostaglandin E1 suppressed B7.1 and CD40 expression, but prostaglandin E2 did not effect on any type of adhesion molecule expression. Both prostaglandins inhibited tumor necrosis factor (TNF)-alpha production and T-cell proliferation of lipopolysaccharide-treated human peripheral blood mononuclear cells (PBMC). Among prostaglandin E1 receptors (IP/EP1/EP2/EP3/EP4) agonists, ONO-1301, a prostanoid IP-receptor agonist, prevented B7.1 and CD40 expression. ONO-AE1-259-01 a prostanoid EP2-receptor agonist, ONO-AE1-329, a prostanoid EP4-receptor agonist, and ONO-1301 inhibited TNF-alpha production and T-cell proliferation. Moreover, anti-B7.1 and anti-CD40 Abs prevented lipopolysaccharide-induced TNF-alpha production and T-cell proliferation. Therefore, the effect of prostaglandin E1 on TNF-alpha production and T-cell proliferation might depend on the inhibition of B7.1 and CD40 expression, but that of prostaglandin E2 might be independent of adhesion molecules expression. In conclusion, the mechanism responsible for the effect of prostaglandin E1 on lipopolysaccharide-induced responses is distinct from that of prostaglandin E2.

  11. Quercetin suppresses hypoxia-induced accumulation of hypoxia-inducible factor-1alpha (HIF-1alpha) through inhibiting protein synthesis.

    Science.gov (United States)

    Lee, Dae-Hee; Lee, Yong J

    2008-10-01

    Quercetin, a ubiquitous bioactive plant flavonoid, has been shown to inhibit the proliferation of cancer cells and induce the accumulation of hypoxia-inducible factor-1alpha (HIF-1alpha) in normoxia. In this study, under hypoxic conditions (1% O(2)), we examined the effect of quercetin on the intracellular level of HIF-1alpha and extracellular level of vascular endothelial growth factor (VEGF) in a variety of human cancer cell lines. Surprisingly, we observed that quercetin suppressed the HIF-1alpha accumulation during hypoxia in human prostate cancer LNCaP, colon cancer CX-1, and breast cancer SkBr3 cells. Quercetin treatment also significantly reduced hypoxia-induced secretion of VEGF. Suppression of HIF-1alpha accumulation during treatment with quercetin in hypoxia was not prevented by treatment with 26S proteasome inhibitor MG132 or PI3K inhibitor LY294002. Interestingly, hypoxia (1% O(2)) in the presence of 100 microM quercetin inhibited protein synthesis by 94% during incubation for 8 h. Significant quercetin concentration-dependent inhibition of protein synthesis and suppression of HIF-1alpha accumulation were observed under hypoxic conditions. Treatment with 100 microM cycloheximide, a protein synthesis inhibitor, replicated the effect of quercetin by inhibiting HIF-1alpha accumulation during hypoxia. These results suggest that suppression of HIF-1alpha accumulation during treatment with quercetin under hypoxic conditions is due to inhibition of protein synthesis. (c) 2008 Wiley-Liss, Inc.

  12. Synchronization of ovulation in crossbred dairy heifers using gonadotrophin-releasing hormone agonist, prostaglandin F2alpha and human chorionic gonadotrophin or estradiol benzoate.

    Science.gov (United States)

    Castilho, C; Gambini, A L; Fernandes, P; Trinca, L A; Teixeira, A B; Barros, C M

    2000-01-01

    Girolando (Gir x Holstein) is a very common dairy breed in Brazil because it combines the rusticity of Gir (Bos indicus) with the high milk yield of Holstein (Bos taurus). The ovarian follicular dynamics and hormonal treatments for synchronization of ovulation and timed artificial insemination were studied in Girolando heifers. The injection of a gonadotrophin-releasing hormone (GnRH) agonist was followed 6 or 7 days (d) later by prostaglandin F2alpha (PGF2alpha). Twenty-four hours after PGF2alpha injection either human chorionic gonadotropin (hCG, GPh-d6 and GPh-d7 groups) or estradiol benzoate (EB, GPE-d6 and GPE-d7 groups) was administered to synchronize ovulation and consequently allow timed artificial insemination (AI) 24 and 30 h after hCG and EB injection, respectively. Follicular dynamics in Girolando heifers was characterized by the predominance of three follicular waves (71.4%) with sizes of dominant follicles (10-13 mm) and corpus luteum (approximately 20 mm) similar to those for Bos indicus cattle. In the GnRH-PGF-hCG protocol, hCG administration induced earlier ovulation (67.4 h, PGirolando heifers was used to determine pregnancy rates in the present study, pregnancy rates should be confirmed with a larger number of animals.

  13. Resveratrol suppresses prostaglandin F(2α)-induced osteoprotegerin synthesis in osteoblasts: inhibition of the MAP kinase signaling.

    Science.gov (United States)

    Kuroyanagi, Gen; Tokuda, Haruhiko; Matsushima-Nishiwaki, Rie; Kondo, Akira; Mizutani, Jun; Kozawa, Osamu; Otsuka, Takanobu

    2014-01-15

    Resveratrol, a natural polyphenol abundantly found in grape skins and red wine, possesses various beneficial properties for human health. In the present study, we investigated the mechanism underlying the effects of prostaglandin F2α (PGF2α) on osteoprotegerin (OPG) synthesis and of resveratrol on the OPG synthesis in osteoblast-like MC3T3-E1 cells. PGF2α stimulated both the release of the OPG protein and the expression of OPG mRNA. Treatment with PD98059, SB203580 and SP600125, specific inhibitors of MEK1/2, p38 mitogen-activated protein (MAP) kinase and stress-activated protein kinase/c-jun N-terminal kinase (SAPK/JNK) all suppressed the OPG release induced by PGF2α. Resveratrol also significantly reduced the PGF2α-stimulated OPG release and the mRNA levels of OPG. Similarly, treatment with SRT1720, an activator of SIRT1, also suppressed the PGF2α-stimulated OPG release. Resveratrol and SRT1720 both attenuated the phosphorylation of p44/p42 MAP kinase, MEK1/2, Raf-1, p38 MAP kinase and SAPK/JNK induced by PGF2α. These findings strongly suggest that resveratrol suppresses PGF2α-stimulated OPG synthesis by inhibiting the MAP kinase pathways in osteoblasts, and that the effect is mediated via SIRT1 activation. Copyright © 2013 Elsevier Inc. All rights reserved.

  14. Flicker light-induced retinal vasodilation is unaffected by inhibition of epoxyeicosatrienoic acids and prostaglandins in humans.

    Science.gov (United States)

    Noonan, Jonathan E; Dusting, Gregory J; Nguyen, Thanh T; Jenkins, Alicia J; Man, Ryan E K; Best, William J; Dias, Daniel A; Jayasinghe, Nirupama S; Roessner, Ute; Lamoureux, Ecosse L

    2014-10-08

    To investigate the role of epoxyeicosatrienoic acids (EETs) and prostaglandins (PGs) in retinal blood vessel calibers and vasodilation during flicker light stimulation in humans. Twelve healthy nonsmokers participated in a balanced crossover study. Oral fluconazole 400 mg and dispersible aspirin 600 mg were used to inhibit production of EETs and PGs, respectively. Retinal imaging was performed 1 hour after drug ingestion with the Dynamic Vessel Analyzer. Resting calibers of selected vessel segments were recorded in measurement units (MU). Maximum percentage dilations during flicker stimulation were calculated from baseline calibers. We then studied six participants each after fluconazole and aspirin ingestions at 30-minute intervals for 2 hours. Within-subject differences were assessed by ANOVA and Dunnett-adjusted pairwise comparisons with significance taken at P flicker stimulation. Mean (SD) resting arteriole and venule calibers on no-drug visits were 119.6 (10.6) MU and 145.7 (17.0) MU, respectively. Fluconazole reduced mean (±95% CI) resting venule calibers by 5.1 (4.3) MU. In repeated measures participants, neither drug affected vasodilations, but fluconazole reduced resting venule calibers over 2 hours (P flicker light-induced retinal vasodilation in humans. However, EETs may play a role in the regulation of retinal vascular tone and blood flow under resting physiological conditions. Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.

  15. Prostaglandin D2 generation by rat peritoneal mast cells stimulated with Datura stramonium agglutinin and its inhibition by haptenic sugar and wheat germ agglutinin.

    Science.gov (United States)

    Suzuki-Nishimura, Tamiko; Uchida, Masaatsu K

    2002-09-01

    The production of prostaglandin D2 (PGD2) by rat peritoneal mast cells incubated with N-acetyl glucosamine (GlcNAc) oligomer-specific Datura stramonium agglutinin (DSA) for 10 min in the presence of 0.3 mM Ca2+ was examined. Previously, our group reported that the incubation of rat mast cells with DSA (5 - 100 microg/ml) under similar conditions resulted in a calcium influx and histamine release via a pertussis toxin-sensitive G-protein pathway of the mast cells, and the histamine release was inhibited by haptenic sugar chitooligosaccharides or GlcNAc-specific lectin wheat germ agglutinin (WGA) (K. Matsuda et al., Jpn J Pharmacol 66, 195 - 204 (1994)). DSA (5 - 100 microg/ml) dose-dependently stimulated the mast cells to generate PGD2. Chitooligosaccharides (1% w/v) and WGA (100 microg/ml) inhibited the production of PGD2 induced by 100 microg/ml of DSA, suggesting that the effect of DSA is sugar-specific. A prostaglandin G/H synthase inhibitor NS-398 (N-[cyclohexyloxy-4-nitrophenyl] methanesulfonamide) (10 microM) inhibited the formation of PGD2 induced by DSA (20 microg/ml). These results suggest that the binding of DSA to the corresponding sugar residues on the mast cell surface mediates the signaling of the prostaglandin G/H synthase pathway.

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

    International Nuclear Information System (INIS)

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

    1988-01-01

    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

  17. Prostaglandin synthesis can be inhibited locally by infusion of NSAIDS through microdialysis catheters in human skeletal muscle

    DEFF Research Database (Denmark)

    Mikkelsen, Ulla Ramer; Helmark, Ida Carøe; Kjaer, Michael

    2008-01-01

    of nonsteroidal anti-inflammatory drugs (NSAIDs). However, to study the local role of prostaglandins, the formation of prostaglandins within the tissue must be controlled. Microdialysis enables determination of local concentrations of water-soluble substances within the tissue. In the present study......, the microdialysis method was used to infuse NSAIDs locally into human skeletal muscles producing a local block of prostaglandin formation. In addition, the graded blockade at various distances from the infusion site within the muscle during rest, exercise and recovery was determined. Microdialysis was performed...... in thigh muscles (vastus lateralis muscle) in six healthy men. One of the microdialysis catheters was used to block prostaglandin synthesis by infusion of the NSAID indomethacin. Additional catheters were placed 1 and 4 cm away from the infusion and in the contralateral leg (working control). Following 2 h...

  18. 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

    International Nuclear Information System (INIS)

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

    1989-01-01

    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)

  19. Very low levels of 6-keto-prostaglandin F /sub 1//sub. cap alpha. / in human plasma

    Energy Technology Data Exchange (ETDEWEB)

    Siess, W.; Dray, F.

    1982-03-01

    Two stable derivatives of PGI/sub 2/, its nonenzymatic hydrolysis product (6-keto-PGF/sub 1//sub ..cap alpha../) and an enzymatic metabolite (6, 15-diketo-PGF/sub 1//sub ..cap alpha../) were determined in human plasma and urine. These compounds were measured by RIA after separation on rp-HPLC. Previous purification of the samples on rp=HPLC markedly enhanced the specificity of the RIA determinations of those compounds in plasma and urine. The PGI/sub 2/ derivative 6-keto-PGF/sub 1//sub ..cap alpha../ was detected in both plasma (4.7 +/- 3.2 pg/ml, mean +/- S.D., n = 34) and urine (166 +/- 61 pg/ml, n = 9). No gender differences of the plasma or urinary levels of 6-keto-PGF/sub 1//sub ..cap alpha../ were found. The PGI/sub 2/ metabolite 6, 15-diketo-PGF/sub 1//sub ..cap alpha../ was not measurable in plasma or urine (<1 and <10 pg/ml, respectively, n = 4). Thus this compound may not be a major endogenous metabolite of PGI/sub 2/ in man. When (/sup 3/H)PGI/sub 2/ was added to citrated blood immediately after venipuncture, it was recovered entirely as (/sup 3/H)6-keto-PGF/sub 1//sub ..cap alpha../ after rp-HPLC. Therefore any circulating PGI/sub 2/ would be measured as 6-keto-PGF/sub 1//sub ..cap alpha../ by our method. The results obtained suggest that PGI/sub 2/ could be present in human venous blood under physiological conditions, but only in very low concentrations.

  20. Dienogest, a synthetic progestin, inhibits prostaglandin E2 production and aromatase expression by human endometrial epithelial cells in a spheroid culture system.

    Science.gov (United States)

    Shimizu, Yutaka; Mita, Shizuka; Takeuchi, Takashi; Notsu, Tatsuto; Mizuguchi, Kiyoshi; Kyo, Satoru

    2011-01-01

    Prostaglandin E(2) (PGE(2)) is a major mediator in the pathophysiology, and pathogenesis of gynecological diseases associated with abnormal endometrial disease with proliferation and inflammation, such as endometriosis. In this study, we investigated the effect of dienogest, a selective progesterone receptor agonist, on PGE(2) production and the expression of aromatase, an estrogen synthase, in human immortalized endometrial epithelial cells. Compared with monolayer culture, the cells showed enhanced PGE(2) production and expression of the PGE(2) synthases cyclooxygenase-2 (COX-2), and microsomal prostaglandin E(2) synthase-1 (mPGES-1) in a spheroid culture system. Dienogest inhibited PGE(2) production and this effect was reversed by RU486, a progesterone receptor antagonist. Dienogest inhibited the PGE(2) synthases mRNA and protein expression, and the nuclear factor-κB activation. Moreover, the suppressive effect of dienogest on PGE(2) production was sustained 24h after the drug was withdrawn. Dienogest but not COX inhibitors inhibited aromatase expression. These results suggest that progesterone receptor activation reduces the gene expressions of COX-2, mPGES-1, and aromatase. Our findings suggest that the pharmacological mechanism of dienogest includes the direct inhibition of PGE(2) synthase and aromatase expression and may contribute to the therapeutic effect on the progression of endometriosis. Copyright © 2010 Elsevier Inc. All rights reserved.

  1. Profiling of luteal transcriptome during prostaglandin F2-alpha treatment in buffalo cows: analysis of signaling pathways associated with luteolysis.

    Directory of Open Access Journals (Sweden)

    Kunal B Shah

    Full Text Available In several species including the buffalo cow, prostaglandin (PG F2α is the key molecule responsible for regression of corpus luteum (CL. Experiments were carried out to characterize gene expression changes in the CL tissue at various time points after administration of luteolytic dose of PGF2α in buffalo cows. Circulating progesterone levels decreased within 1 h of PGF2α treatment and evidence of apoptosis was demonstrable at 18 h post treatment. Microarray analysis indicated expression changes in several of immediate early genes and transcription factors within 3 h of treatment. Also, changes in expression of genes associated with cell to cell signaling, cytokine signaling, steroidogenesis, PG synthesis and apoptosis were observed. Analysis of various components of LH/CGR signaling in CL tissues indicated decreased LH/CGR protein expression, pCREB levels and PKA activity post PGF2α treatment. The novel finding of this study is the down regulation of CYP19A1 gene expression accompanied by decrease in expression of E2 receptors and circulating and intra luteal E2 post PGF2α treatment. Mining of microarray data revealed several differentially expressed E2 responsive genes. Since CYP19A1 gene expression is low in the bovine CL, mining of microarray data of PGF2α-treated macaques, the species with high luteal CYP19A1 expression, showed good correlation between differentially expressed E2 responsive genes between both the species. Taken together, the results of this study suggest that PGF2α interferes with luteotrophic signaling, impairs intra-luteal E2 levels and regulates various signaling pathways before the effects on structural luteolysis are manifest.

  2. Increased plasma concentrations of vasopressin, oxytocin, cortisol and the prostaglandin F2alpha metabolite during labour in the dog.

    Science.gov (United States)

    Olsson, K; Bergström, A; Kindahl, H; Lagerstedt, A-S

    2003-11-01

    This study investigated if the plasma vasopressin concentration increases during labour in the dog and whether the change in vasopressin correlates with that of oxytocin, 15-ketodihydro-PGF2alpha and cortisol. Five beagle dogs each delivered three to seven puppies. Blood samples were taken from a catheter inserted into the cephalic vein during labour and by venepuncture during the other periods. Vasopressin concentration increased from 2 +/- 0 pmol L-1 (anoestrus) to 26 +/- 11 pmol L-1 at the birth of the first puppy, remained high at the birth of the second puppy and then decreased. Oxytocin increased from 63 +/- 5 pmol L-1 (anoestrus) to 166 +/- 19 pmol L-1 at the birth of the first puppy and remained elevated throughout labour. The PGF2alpha metabolite concentration increased from 0.2 +/- 0.0 nmol L-1 (anoestrus) to 66 +/- 17 nmol L-1 at the birth of the first puppy and remained elevated 1 h after the completion of parturition. The cortisol concentration increased from 49 +/- 9 nmol L-1 (anoestrus) to 242 +/- 35 nmol L-1 at the birth of the first puppy, remained high during the birth of the second puppy and then declined. The plasma level of vasopressin was strongly correlated with that of cortisol but less with that of the PGF2alpha metabolite, and not significantly with the concentration of oxytocin. This indicates that the four hormones play different roles during labour in the dog.

  3. Elevated concentrations of 13,14-dihydro-15-keto-prostaglandin F-2 alpha in maternal plasma during prepartum luteolysis and parturition in dogs (Canis familiaris).

    Science.gov (United States)

    Concannon, P W; Isaman, L; Frank, D A; Michel, F J; Currie, W B

    1988-09-01

    Concentrations of progesterone and of 13,14-dihydro-15-keto-prostaglandin F-2 alpha (PGFM) were measured in plasma collected from 6 bitches every 3 h starting 2.8-4.6 days before parturition (birth of first pup) and continuing until 0.4-0.8 days post partum, and in additional samples collected less frequently. Progesterone concentrations at 48, 24, 12 and 3 h pre partum averaged 2.8 +/- 0.3, 2.2 +/- 0.4, 1.0 +/- 0.3 and 0.7 +/- 0.2 ng/ml. At those times PGFM values averaged 380 +/- 80, 800 +/- 220, 1450 +/- 450 and 1930 +/- 580 pg/ml, respectively. Mean concentrations of PGFM increased about 2.5-fold between 48 and 15 h pre partum in association with the onset of luteolysis, and then increased another 2.5 times before parturition as progesterone fell to nadir values. Peak levels of PGFM ranged from 1060 to 7150 pg/ml (2100 +/- 600 pg/ml) and occurred within 1-9 h after the birth of the first pup and before the birth of the last pup. These results suggest that prepartum luteolysis in dogs is initiated by increases in maternal concentrations of PGF, and that progesterone withdrawal causes a further increase in PGF which completes luteolysis and provides a major portion of the uterotonic activity causing expulsion of pups.

  4. Sex, drugs and sports: prostaglandins, epitestosterone and sexual development.

    Science.gov (United States)

    Sanders, Bryan K

    2007-01-01

    Amateau and McCarthy's findings published in Nature Neuroscience (June 2004) are noteworthy for suggesting a role for prostaglandins in sexual development. However, evidence suggests that in manipulating PGE2, they unknowingly implicated 3alpha-hydroxysteroid dehydrogenase [E.C. 1.1.1.50], 3(or 17)alpha-hydroxysteroid dehydrogenase [E.C. 1.1.1.209] and their respective products, androsterone (ADT) and epitestosterone (EpiT), in the developmental masculinization of sex behavior. EpiT is generally regarded as a hormonally inactive 17alpha-epimer of testosterone (T). In rats, the kidney is the primary site of EpiT formation, whereas in humans it originates from the gonads, with only a small contribution secreted by the adrenals. Because the ratio of T to EpiT is nearly constant, it is presently used for assessing steroid abuse in competitive sports, where the World Anti-Doping Agency (WADA) considers a T/EpiT ratio >4 evidence of T doping. Despite its central role in the detection of illict anabolic steroid use, our knowledge of factors effecting EpiT production is poor. Clues in the literature, however, reveal that prostaglandin-mediated processes, such as LHRH release, may influence its production. Antimycotics, NSAIDs, and opioid analgesics used in sports medicine are all known to effect prostaglandin E2 synthesis. Primary PGs are potent inhibitors of ADT oxidation, while indomethacin, a prostaglandin blocker, powerfully inhibits 3alpha-HSD reduction and ADT oxidation. This is significant because ADT inhibits the oxidation of EpiT, and may modulate its antiandrogenic and neuroprotective effects. It is hypothesized that the T/EpiT ratio is increased by COX-2 inhibitors and opiod analgesics, and decreased by antimycotics that do not impair testosterone biosynthesis. Given the devastating personal and career consequences that may result from false positive drug tests, substantive research on the effects of PGE2 manipulations on EpiT is warranted.

  5. TNF-alpha and IL-6 synergistically inhibit ketogenesis from fatty acids and alpha-ketoisocaproate in isolated rat hepatocytes.

    Science.gov (United States)

    Pailla, K; Lim, S K; De Bandt, J P; Aussel, C; Giboudeau, J; Troupel, S; Cynober, L; Blonde-Cynober, F

    1998-01-01

    During sepsis, lipid metabolism is shunted toward triacylglycerol synthesis and hepatic lipogenesis. A decrease in ketogenesis from free fatty acids also is observed, probably mediated by cytokines involved in host response to infection. Whether such an inhibition of ketogenesis occurs with other ketone body precursors such as ketoacids is not known. The aim of this study was to determine the effects of tumor necrosis factor alpha (TNF-alpha) and interleukin 6 (IL-6) on hepatic ketone body production from octanoic acid, a medium-chain fatty acid, and from alpha-ketoisocaproate (KIC), the ketoanalogue of leucine. The experiments were conducted in cultured hepatocytes isolated from 24-hour-fasted Sprague-Dawley rats. Hepatocyte monolayers were incubated for 6 hours, with either KIC or octanoic acid (1 mmol/L), in the presence of glucagon and TNF-alpha (25 micro/L) IL-6 (15 microg/L) and/or IL-6. Acetoacetate, beta-hydroxybutyrate, and free fatty acids were determined in culture medium by enzymatic methods and KIC was measured by high-performance liquid chromatography. KIC and octanoic acid uptake by hepatocytes was 79% and 92%, respectively, over 6 hours, and cytokines had no influence. However, TNF-alpha and IL-6 caused inhibition of ketogenesis from alpha-ketoisocaproate (5.6% +/- 2.3% and 4.4% +/- 3.0%, respectively), and from octanoic acid (7.9% +/- 2.9%, 5.7% +/- 3.2%, respectively). In addition, when the two cytokines were present together in the culture medium, the inhibition was enhanced (inhibition of ketogenesis from KIC: 14.0% +/- 4.8%; from octanoic acid: 11.6% +/- 3.4%). In our experimental conditions, cytokines mediate an inhibition of ketogenesis; this process could be explained by a direct effect of cytokines on metabolic pathways of octanoic acid and KIC oran indirect effect by modification of the mitochondrial redox state.

  6. Selective inhibition of hepatitis C virus replication by alpha-zam, a ...

    African Journals Online (AJOL)

    Selective inhibition of hepatitis C virus replication by alpha-zam, a Nigella sativa seed formulation. Olufunmilayo G. Oyero, Masaaki Toyama, Naoki Mitsuhiro, Abdulfatah A. Onifade, Akemi Hidaka, Mika Okamoto, Masanori Baba ...

  7. Flavan-3-ols isolated from some medicinal plants inhibiting COX-1 and COX-2 catalysed prostaglandin biosynthesis.

    Science.gov (United States)

    Noreen, Y; Serrano, G; Perera, P; Bohlin, L

    1998-08-01

    Extracts from the four plant species Atuna racemosa Raf. ssp. racemosa, Syzygium corynocarpum (A. Gray) C. Muell., Syzygium malaccense (L.) Merr. & Perry and Vantanea peruviana Macbr., traditionally used for inflammatory conditions, were fractionated using a cyclooxygenase-1 catalysed prostaglandin biosynthesis in vitro assay. The flavan-3-ol derivatives (+)-catechin, (+)-gallocatechin, 4'-O-Me-ent-gallocatechin, ouratea-catechin and ouratea-proanthocynidin A were isolated as active principles. The IC50 values ranged from 3.3 microM to 138 microM whilst indomethacin under the same test conditions had an IC50 value of 1.1 microM. The flavonol rhamnosides mearnsitrin, myricitrin and quercitrin were also isolated. When further tested for inhibitory effect on cyclooxygenase-2 catalysed prostaglandin biosynthesis, the five flavan-3-ol derivatives exhibited from equal to weaker inhibitory potencies, as compared to their cyclooxygenase-1 inhibitory effects. The flavonol rhamnosides were inactive towards both enzymes.

  8. Corrosion inhibition of alpha brass by 1-phenyl-3-methyl-pyrazol-5 ...

    African Journals Online (AJOL)

    Corrosion inhibition of alpha brass by 1-phenyl-3-methyl-pyrazol-5-one in acidic media at different temperatures. ... Global Journal of Engineering Research ... The corrosion inhibition efficiency (C.I.E.) of the alpha brass was 99.83%, using the condition of 3.0M HNO3 for the uninhibited experiment and 0.03M HPMP for the ...

  9. Oxytocin, vasopressin, prostaglandin F(2alpha), luteinizing hormone, testosterone, estrone sulfate, and cortisol plasma concentrations after sexual stimulation in stallions.

    Science.gov (United States)

    Veronesi, M C; Tosi, U; Villani, M; Govoni, N; Faustini, M; Kindahl, H; Madej, A; Carluccio, A

    2010-03-01

    This experiment was designed to determine the effects of sexual stimulation on plasma concentrations of oxytocin (OT), vasopressin (VP), 15-ketodihydro-PGF(2alpha) (PG-metabolite), luteinizing hormone (LH), testosterone (T), estrone sulfate (ES), and cortisol (C) in stallions. Semen samples were collected from 14 light horse stallions (Equus caballus) of proven fertility using a Missouri model artificial vagina. Blood samples were collected at 15, 12, 9, 6, and 3 min before estrous mare exposure, at erection, at ejaculation, and at 3, 6, and 9 min after ejaculation. Afterwards, blood sampling was performed every 10 min for the following 60 min. Sexual activity determined an increase in plasma concentrations of OT, VP, C, PG-metabolite, and ES and caused no changes in LH and T concentrations. The finding of a negative correlation between C and VP at erection, and between C and T before erection and at the time of erection, could be explained by a possible inhibitory role exerted by C in the mechanism of sexual arousal described for men. Copyright 2010 Elsevier Inc. All rights reserved.

  10. Inhibition of tumor necrosis factor-alpha with anti-diabetic agents.

    Science.gov (United States)

    Fukuzawa, M; Satoh, J; Qiang, X; Miyaguchi, S; Sakata, Y; Nakazawa, T; Ikehata, F; Ohta, S; Toyota, T

    1999-03-01

    It has recently been indicated that tumor necrosis factor-alpha (TNF-alpha) production is increased under chronic hyperglycemia and TNF-alpha has harmful effects on insulin sensitivity and possibly on chronic diabetic complications. Therefore it will be favorable for diabetes treatment if anti-diabetic agents also have anti-TNF-alpha activities. In this study, we have investigated effects of hypoglycemic sulfonylureas (gliclazide and glibenclamide) and a thiazolidinedione (troglitazone) on lipopolysaccharide-induced TNF-alpha production, which was evaluated by immunoassay and bioassay, in vivo using mice and partly in vitro using human peripheral blood mononuclear cells. Gliclazide significantly inhibited TNF-alpha production in vivo and also in vitro at a concentration of 10(-3) mol/l. However, glibenclamide had neither effect on TNF-alpha production nor action. On the other hand, troglitazone inhibited action rather than production of TNF-alpha in vivo. In vitro troglitazone (10(-4) mol/l) significantly reduced cytolytic activity of TNF-alpha against LM cells. These results indicate that gliclazide and troglitazone have inhibitory effect on TNF-alpha.

  11. Pre-treatment with Toll-like receptor 4 antagonist inhibits lipopolysaccharide-induced preterm uterine contractility, cytokines, and prostaglandins in rhesus monkeys

    Science.gov (United States)

    Adams Waldorf, Kristina M.; Persing, David; Novy, Miles J.; Sadowsky, Drew W.; Gravett, Michael G.

    2009-01-01

    Intra-uterine infection, which occurs in the majority of early preterm births, triggers an immune response culminating in preterm labor. We hypothesized that blockade of lipopolysaccharide (LPS)-induced immune responses by a Toll-like receptor 4 antagonist (TLR4A) would prevent elevations in amniotic fluid (AF) cytokines, prostaglandins, and uterine contractility. Chronically catheterized rhesus monkeys at 128-147 days gestation received intra-amniotic infusions of either: 1) saline (n=6), 2) LPS (0.15-10μg; n=4), or 3) TLR4A pre-treatment with LPS (10 μg) one hour later (n=4). AF cytokines, prostaglandins, and uterine contractility were compared using oneway ANOVA with Bonferroni-adjusted pairwise comparisons. Compared to saline controls, LPS induced significant elevations in AF IL-8, TNF-α, PGE2, PGF2α, and uterine contractility (p<0.05). In contrast, TLR4A pre-treatment inhibited LPS-induced uterine activity and was associated with significantly lower AF IL-8, TNF-α, PGE2, and PGF2α versus LPS alone (p<0.05). Toll-like receptor antagonists, together with antibiotics, may delay or prevent infection-associated preterm birth. PMID:18187405

  12. Pentoxifylline inhibits tumor necrosis factor-alpha (TNF alpha)-induced T-lymphoma cell adhesion to endothelioma cells.

    Science.gov (United States)

    Weiss, J M; Vanscheidt, W; Pilarski, K A; Weyl, A; Peschen, M; Schöpf, E; Vestweber, D; Simon, J C

    1995-05-01

    Pentoxifylline, a methylxanthine derivative, has been shown to inhibit T-cell-mediated cutaneous immune response by yet ill-understood mechanisms. Because cell adhesion to endothelial cells is a critical step in the initiation of such immune responses, we analyzed whether pentoxifylline would affect this process. To address this issue, adhesion of mouse T-lymphoma cells (TK-1) to mouse endothelioma cells (eEnd.2), either untreated or stimulated with tumor necrosis factor-alpha (TNF alpha), was studied. Pentoxifylline reduced the ability of endothelioma cells stimulated with different concentrations of TNF alpha, but not of untreated endothelioma cells, to bind T-lymphoma cells in dose-dependent (10(-5)-10(-3) M) fashion. Selective incubation of either endothelioma cells or T-lymphoma cells revealed that pentoxifylline acted exclusively on the endothelioma cells, even when added after TNF alpha stimulation. We questioned whether pentoxifylline suppressed T-lymphoma cell/endothelioma cell interactions by interfering with adhesion molecules expressed by either cell. However, as determined by flow cytometry, pentoxifylline did not alter TNF alpha-induced upregulation of intercellular adhesion molecule-1 or vascular cellular adhesion molecule-1 on endothelioma cells nor did it affect constitutive CD11a, CD18, or alpha 4-integrin expression on T-lymphoma cells, suggesting that rather than affecting quantitative expression of these adhesion molecules, pentoxifylline might modulate their avidity. We conclude that pentoxifylline in therapeutically achievable concentrations is a potent inhibitor of TNF alpha-induced T-lymphoma cell adhesion to endothelioma cells. This finding may account, at least in part, for the recently discovered anti-inflammatory action of pentoxifylline.

  13. CREB inhibits AP-2alpha expression to regulate the malignant phenotype of melanoma.

    Directory of Open Access Journals (Sweden)

    Vladislava O Melnikova

    2010-08-01

    Full Text Available The loss of AP-2alpha and increased activity of cAMP-responsive element binding (CREB protein are two hallmarks of malignant progression of cutaneous melanoma. However, the molecular mechanism responsible for the loss of AP-2alpha during melanoma progression remains unknown.Herein, we demonstrate that both inhibition of PKA-dependent CREB phosphorylation, as well as silencing of CREB expression by shRNA, restored AP-2alpha protein expression in two metastatic melanoma cell lines. Moreover, rescue of CREB expression in CREB-silenced cell lines downregulates expression of AP-2alpha. Loss of AP-2alpha expression in metastatic melanoma occurs via a dual mechanism involving binding of CREB to the AP-2alpha promoter and CREB-induced overexpression of another oncogenic transcription factor, E2F-1. Upregulation of AP-2alpha expression following CREB silencing increases endogenous p21(Waf1 and decreases MCAM/MUC18, both known to be downstream target genes of AP-2alpha involved in melanoma progression.Since AP-2alpha regulates several genes associated with the metastatic potential of melanoma including c-KIT, VEGF, PAR-1, MCAM/MUC18, and p21(Waf1, our data identified CREB as a major regulator of the malignant melanoma phenotype.

  14. Muscarinic M1 receptor inhibition reduces gastroduodenal bicarbonate secretion and promotes gastric prostaglandin E2 synthesis in healthy volunteers

    DEFF Research Database (Denmark)

    Mertz-Nielsen, A; Hillingsø, Jens; Eskerod, O

    1995-01-01

    The selective muscarinic M1 receptor antagonist, pirenzepine, considerably stimulates duodenal mucosal bicarbonate secretion in the rat and increases gastric luminal release of prostaglandin E2 (PGE2) in humans. This study, therefore, looked at the effect of pirenzepine on bicarbonate secretion...... and luminal output of PGE2 into the stomach and the duodenum of nine healthy volunteers using a new technique permitting simultaneous measurements. In the stomach modified sham feeding increased bicarbonate secretion from 382 (62) mumol/h (mean (SEM)) to 959 (224) mumol/h (p ... sham feeding and acid exposure (HCl 0.1 M; 20 ml; 5 min) of the duodenal bulb increased mucosal bicarbonate secretion from 191 (14) mumol/cm x h to 266 (27) mumol/cm x h (p

  15. Endogenous levels of Echinacea alkylamides and ketones are important contributors to the inhibition of prostaglandin E2 and nitric oxide production in cultured macrophages.

    Science.gov (United States)

    LaLone, Carlie A; Rizshsky, Ludmila; Hammer, Kimberly D P; Wu, Lankun; Solco, Avery K S; Yum, Manyu; Nikolau, Basil J; Wurtele, Eve S; Murphy, Patricia A; Kim, Meehye; Birt, Diane F

    2009-10-14

    Because of the popularity of Echinacea as a dietary supplement, researchers have been actively investigating which Echinacea constituent or groups of constituents are necessary for immune-modulating bioactivities. Our prior studies indicate that alkylamides may play an important role in the inhibition of prostaglandin E2 (PGE(2)) production. High-performance liquid chromatography fractionation, employed to elucidate interacting anti-inflammatory constituents from ethanol extracts of Echinacea purpurea, Echinacea angustifolia, Echinacea pallida, and Echinacea tennesseensis, identified fractions containing alkylamides and ketones as key anti-inflammatory contributors using lipopolysaccharide-induced PGE(2) production in RAW264.7 mouse macrophage cells. Nitric oxide (NO) production and parallel cytotoxicity screens were also employed to substantiate an anti-inflammatory response. E. pallida showed significant inhibition of PGE(2) with a first round fraction, containing gas chromatography-mass spectrometry (GC-MS) peaks for Bauer ketones 20, 21, 22, 23, and 24, with 23 and 24 identified as significant contributors to this PGE(2) inhibition. Chemically synthesized Bauer ketones 21 and 23 at 1 microM each significantly inhibited both PGE(2) and NO production. Three rounds of fractionation were produced from an E. angustifolia extract. GC-MS analysis identified the presence of Bauer ketone 23 in third round fraction 3D32 and Bauer alkylamide 11 making up 96% of third round fraction 3E40. Synthetic Bauer ketone 23 inhibited PGE(2) production to 83% of control, and synthetic Bauer alkylamide 11 significantly inhibited PGE(2) and NO production at the endogenous concentrations determined to be present in their respective fraction; thus, each constituent partially explained the in vitro anti-inflammatory activity of their respective fraction. From this study, two key contributors to the anti-inflammatory properties of E. angustifolia were identified as Bauer alkylamide 11 and

  16. Alpha-mangostin inhibits intracellular fatty acid synthase and induces apoptosis in breast cancer cells

    OpenAIRE

    Li, Ping; Tian, Weixi; Ma, Xiaofeng

    2014-01-01

    Background Fatty acid synthase (FAS) has been proven over-expressed in human breast cancer cells and consequently, has been recognized as a target for breast cancer treatment. Alpha-mangostin, a natural xanthone found in mangosteen pericarp, has a variety of biological activities, including anti-cancer effect. In our previous study, alpha-mangostin had been found both fast-binding and slow-binding inhibitions to FAS in vitro. This study was designed to investigate the activity of alpha-mangos...

  17. D-Glucosamine down-regulates HIF-1{alpha} through inhibition of protein translation in DU145 prostate cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jee-Young; Park, Jong-Wook; Suh, Seong-Il [Chronic Disease Research Center, School of Medicine, Keimyung University, 194 Dongsan-Dong, Jung-Gu, Daegu 700-712 (Korea, Republic of); Baek, Won-Ki, E-mail: wonki@dsmc.or.kr [Chronic Disease Research Center, School of Medicine, Keimyung University, 194 Dongsan-Dong, Jung-Gu, Daegu 700-712 (Korea, Republic of)

    2009-04-24

    D-Glucosamine has been reported to inhibit proliferation of cancer cells in culture and in vivo. In this study we report a novel response to D-glucosamine involving the translation regulation of hypoxia inducible factor (HIF)-1{alpha} expression. D-Glucosamine caused a decreased expression of HIF-1{alpha} under normoxic and hypoxic conditions without affecting HIF-1{alpha} mRNA expression in DU145 prostate cancer cells. D-Glucosamine inhibited HIF-1{alpha} accumulation induced by proteasome inhibitor MG132 and prolyl hydroxylase inhibitor DMOG suggesting D-glucosamine reduces HIF-1{alpha} protein expression through proteasome-independent pathway. Metabolic labeling assays indicated that D-glucosamine inhibits translation of HIF-1{alpha} protein. In addition, D-glucosamine inhibited HIF-1{alpha} expression induced by serum stimulation in parallel with inhibition of p70S6K suggesting D-glucosamine inhibits growth factor-induced HIF-1{alpha} expression, at least in part, through p70S6K inhibition. Taken together, these results suggest that D-glucosamine inhibits HIF-1{alpha} expression through inhibiting protein translation and provide new insight into a potential mechanism of the anticancer properties of D-glucosamine.

  18. 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

  19. Alpha 1-adrenergic receptor-mediated phosphoinositide hydrolysis and prostaglandin E2 formation in Madin-Darby canine kidney cells. Possible parallel activation of phospholipase C and phospholipase A2

    International Nuclear Information System (INIS)

    Slivka, S.R.; Insel, P.A.

    1987-01-01

    alpha 1-Adrenergic receptors mediate two effects on phospholipid metabolism in Madin-Darby canine kidney (MDCK-D1) cells: hydrolysis of phosphoinositides and arachidonic acid release with generation of prostaglandin E2 (PGE2). The similarity in concentration dependence for the agonist (-)-epinephrine in eliciting these two responses implies that they are mediated by a single population of alpha 1-adrenergic receptors. However, we find that the kinetics of the two responses are quite different, PGE2 production occurring more rapidly and transiently than the hydrolysis of phosphoinositides. The antibiotic neomycin selectively decreases alpha 1-receptor-mediated phosphatidylinositol 4,5-bisphosphate hydrolysis without decreasing alpha 1-receptor-mediated arachidonic acid release and PGE2 generation. In addition, receptor-mediated inositol trisphosphate formation is independent of extracellular calcium, whereas release of labeled arachidonic acid is largely calcium-dependent. Moreover, based on studies obtained with labeled arachidonic acid, receptor-mediated generation of arachidonic acid cannot be accounted for by breakdown of phosphatidylinositol monophosphate, phosphatidylinositol bisphosphate, or phosphatidic acid. Further studies indicate that epinephrine produces changes in formation or turnover of several classes of membrane phospholipids in MDCK cells. We conclude that alpha 1-adrenergic receptors in MDCK cells appear to regulate phospholipid metabolism by the parallel activation of phospholipase C and phospholipase A2. This parallel activation of phospholipases contrasts with models described in other systems which imply sequential activation of phospholipase C and diacylglycerol lipase or phospholipase A2

  20. Tartrazine and the prostaglandin system.

    Science.gov (United States)

    Gerber, J G; Payne, N A; Oelz, O; Nies, A S; Oates, J A

    1979-04-01

    The effect of tartrazine on prostaglandin production was evaluated in several in vitro systems in order to elucidate the interrelationship between aspirin-sensitive asthma and tartrazine. Unlike the nonsteroidal anti-inflammatory drugs, tartrazine did not inhibit cyclooxygenase activity in sheep seminal vesicles, guinea pig lung microsomes, and human platelets. Tartrazine had no effect on the activation of acyl hydrolase, which is the rate-limiting step in prostaglandin production. The major metabolite of tartrazine, sulfanilic acid, also had no inhibitory effect on the sheep seminal vesicle cyclooxygenase. In view of these findings, if there is a cross-sensitivity between tartrazine and aspirin in aspirin-sensitive asthmatics, it is unlikely to be on the basis of prostaglandin inhibition.

  1. Prostaglandin E2Inhibits Histamine-Evoked Ca2+Release in Human Aortic Smooth Muscle Cells through Hyperactive cAMP Signaling Junctions and Protein Kinase A.

    Science.gov (United States)

    Taylor, Emily J A; Pantazaka, Evangelia; Shelley, Kathryn L; Taylor, Colin W

    2017-11-01

    In human aortic smooth muscle cells, prostaglandin E 2 (PGE 2 ) stimulates adenylyl cyclase (AC) and attenuates the increase in intracellular free Ca 2+ concentration evoked by activation of histamine H 1 receptors. The mechanisms are not resolved. We show that cAMP mediates inhibition of histamine-evoked Ca 2+ signals by PGE 2 Exchange proteins activated by cAMP were not required, but the effects were attenuated by inhibition of cAMP-dependent protein kinase (PKA). PGE 2 had no effect on the Ca 2+ signals evoked by protease-activated receptors, heterologously expressed muscarinic M3 receptors, or by direct activation of inositol 1,4,5-trisphosphate (IP 3 ) receptors by photolysis of caged IP 3 The rate of Ca 2+ removal from the cytosol was unaffected by PGE 2 , but PGE 2 attenuated histamine-evoked IP 3 accumulation. Substantial inhibition of AC had no effect on the concentration-dependent inhibition of Ca 2+ signals by PGE 2 or butaprost (to activate EP 2 receptors selectively), but it modestly attenuated responses to EP 4 receptors, activation of which generated less cAMP than EP 2 receptors. We conclude that inhibition of histamine-evoked Ca 2+ signals by PGE 2 occurs through "hyperactive signaling junctions," wherein cAMP is locally delivered to PKA at supersaturating concentrations to cause uncoupling of H 1 receptors from phospholipase C. This sequence allows digital signaling from PGE 2 receptors, through cAMP and PKA, to histamine-evoked Ca 2+ signals. Copyright © 2017 by The Author(s).

  2. Enzyme binding selectivity prediction: alpha-thrombin vs trypsin inhibition.

    Science.gov (United States)

    Mlinsek, G; Novic, M; Kotnik, M; Solmajer, T

    2004-01-01

    In the present work we explore the possibility of an in-depth computational analysis of available experimental X-ray structures in the specific case of a series of alpha-thrombin and trypsin complexes with their respective inhibitors for the development of a novel scoring function based on molecular electrostatic potential computed at the contact surface in the enzyme-inhibitor molecular complex. We subsequently employ the chemometrical approach to determine which are the interactions in the large volume of data that determine the resulting experimental binding constant between ligand and receptor. The results of the model evaluated with molecules in the independent validation set show that a reasonable average error of 1.30 log units of the difference between experimental and calculated binding constants was achieved in the system thrombin-trypsin, which is comparable with those of methods from the literature. Furthermore, by a careful preparation of the Kohonen top layer in the artificial neural network approach that is normally perceived as a "black box device", we have been able to follow the implications of the structure of the inhibitor-enzyme complex for the inhibitor's binding constant. The method appears to be suitable for evaluation of selectivity in structurally similar enzymatic systems, which is currently an important problem in drug design. Copyright 2004 American Chemical Society

  3. Pulsed Out of Awareness: EEG Alpha oscillations represent a pulsed inhibition of ongoing cortical processing

    Directory of Open Access Journals (Sweden)

    Kyle Elliott Mathewson

    2011-05-01

    Full Text Available Alpha oscillations are ubiquitous in the brain, but their role in cortical processing remains a matter of debate. Recently, evidence has begun to accumulate in support of a role for alpha oscillations in attention selection and control. Here we first review evidence that 8-12 Hz oscillations in the brain have a general inhibitory role in cognitive processing, with an emphasis on their role in visual processing. Then, we summarize the evidence in support of our recent proposal that alpha represents a pulsed inhibition of ongoing neural activity. The phase of the ongoing EEG can influence evoked activity and subsequent processing, and we propose that alpha exerts its inhibitory role through alternating microstates of inhibition and excitation. Finally, we discuss evidence that this pulsed inhibition can be entrained to rhythmic stimuli in the environment, such that preferential processing occurs for stimuli at predictable moments. The entrainment of preferential phase may provide a mechanism for temporal attention in the brain. This pulsed inhibitory account of alpha has important implications for many common cognitive phenomena, such as the attentional blink, and seems to indicate that our visual experience may at least some times be coming through in waves.

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

    Science.gov (United States)

    Ruan, Diana; So, Shui-Ping

    2012-08-31

    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 E(2) (PGE(2))-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 PGE(2) receptors and an HEK293 cell line specifically expressing the recombinant human PGE(2) receptor subtype-1 (EP(1)) 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 PGE(2). It was identified that fish oil best inhibited the PGE(2) 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 PGE(2) signaling. Eicosapentaenoic acid (EPA), another major fatty acid found in fish oil and tested in this study was found to have small effect on EP(1) signaling. The study suggested one of the four PGE(2) subtype receptors, EP(1) as the key target for the fish oil and DHA target. These findings were further confirmed by using the recombinant EP(1) expressed in HEK293 cells as a target. 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 EP(1)-mediated PGE(2) receptor signaling, and that the inflammatory response stimulated by PGE(2) 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 disease, pain, and cancer

  5. 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

  6. 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.

  7. Curcumin inhibition of integrin (alpha6beta4)-dependent breast cancer cell motility and invasion.

    Science.gov (United States)

    Kim, Hong Im; Huang, Huang; Cheepala, Satish; Huang, Shile; Chung, Jun

    2008-10-01

    Curcumin, a polyphenol natural product isolated from the rhizome of the plant Curcuma longa, has emerged as a promising anticancer therapeutic agent. However, the mechanism by which curcumin inhibits cancer cell functions such as cell growth, survival, and cell motility is largely unknown. We explored whether curcumin affects the function of integrin alpha(6)beta(4), a laminin adhesion receptor with an established role in invasion and migration of cancer cells. Here we show that curcumin significantly reduced alpha(6)beta(4)-dependent breast cancer cell motility and invasion in a concentration-dependent manner without affecting apoptosis in MDA-MB-435/beta4 (beta(4)-integrin transfectants) and MDA-MB-231 breast cancer cell lines. Further, curcumin selectively reduced the basal phosphorylation of beta(4) integrin (Y1494), which has been reported to be essential in mediating alpha(6)beta(4)-dependent phosphatidylinositol 3-kinase activation and cell motility. Consistent with this finding, curcumin also blocked alpha(6)beta(4)-dependent Akt activation and expression of the cell motility-promoting factor ENPP2 in MDA-MB-435/beta4 cell line. A multimodality approach using curcumin in combination with other pharmacologic inhibitors of alpha(6)beta(4) signaling pathways showed an additive effect to block breast cancer cell motility and invasion. Taken together, these findings show that curcumin inhibits breast cancer cell motility and invasion by directly inhibiting the function of alpha(6)beta(4) integrin, and suggest that curcumin can serve as an effective therapeutic agent in tumors that overexpress alpha(6)beta(4).

  8. Nutrient Content, Phytonutrient Composition, Alpha Amylase, Alpha Glucosidase Inhibition Activity and Antioxidant Activity of the Stoechospermum Marginatum Collected in Pre Monsoon Season

    Directory of Open Access Journals (Sweden)

    Reka Palanivel

    2017-03-01

    Full Text Available The objective of this study was to investigate the nutrient content, phytonutrient composition, physicochemical properties, alpha amylase and alpha glucosidase inhibition activity and antioxidant activity of the brown algae Stoechospermum marginatum collected from Gulf of Mannar, Tamil Nadu, India in pre monsoon season (June- September, 2015. Six and eight hours of ethanol and aqueous extract of Stoechospermum marginatum were used for phytonutrient screening, alpha amylase, alpha glucosidase inhibition activity and antioxidant activity. From the results of the study it is understood that Stoechospermum marginatum contain a high amount of carbohydrate, protein, crude fiber and phytonutrients like tannin, flavonoid, saponin, alkaloid, terpenoids, steroid and total phenolic content. The physicochemical properties namely Water absorption and Swelling power were very promising. Alpha amylase and alpha glucosidase inhibition activity was recorded to be high in both aqueous and ethanol extracts of eight hour extraction than in extracts taken from six hours extraction. Antioxidant activity was detected using DPPH, FRAP, beta carotene scavenging and H2O2 assay and found to have a high radical scavenging activity. Stoechospermum marginatum possess a valuable amount of total phenolic content and other phytonutrients and physicochemical properties, it may the reason for the potential inhibition of alpha amylase, alpha glucosidase and antioxidant activity. It is concluded from the study that the brown algae may be incorporated into foods to enhance their nutritional and therapeutic value.

  9. Alpha-mangostin inhibits intracellular fatty acid synthase and induces apoptosis in breast cancer cells.

    Science.gov (United States)

    Li, Ping; Tian, Weixi; Ma, Xiaofeng

    2014-06-03

    Fatty acid synthase (FAS) has been proven over-expressed in human breast cancer cells and consequently, has been recognized as a target for breast cancer treatment. Alpha-mangostin, a natural xanthone found in mangosteen pericarp, has a variety of biological activities, including anti-cancer effect. In our previous study, alpha-mangostin had been found both fast-binding and slow-binding inhibitions to FAS in vitro. This study was designed to investigate the activity of alpha-mangostin on intracellular FAS activity in FAS over-expressed human breast cancer cells, and to testify whether the anti-cancer activity of alpha-mangostin may be related to its inhibitory effect on FAS. We evaluated the cytotoxicity of alpha-mangostin in human breast cancer MCF-7 and MDA-MB-231 cells. Intracellular FAS activity was measured by a spectrophotometer at 340 nm of NADPH absorption. Cell Counting Kit assay was used to test the cell viability. Immunoblot analysis was performed to detect FAS expression level, intracellular fatty acid accumulation and cell signaling (FAK, ERK1/2 and AKT). Apoptotic effects were detected by flow cytometry and immunoblot analysis of PARP, Bax and Bcl-2. Small interfering RNA was used to down-regulate FAS expression and/or activity. Alpha-mangostin could effectively suppress FAS expression and inhibit intracellular FAS activity, and result in decrease of intracellular fatty acid accumulation. It could also reduce cell viability, induce apoptosis in human breast cancer cells, increase in the levels of the PARP cleavage product, and attenuate the balance between anti-apoptotic and pro-apoptotic proteins of the Bcl-2 family. Moreover, alpha-mangostin inhibited the phosphorylation of FAK. However, the active forms of AKT, and ERK1/2 proteins were not involved in the changes of FAS expression induced by alpha-mangostin. Alpha-mangostin induced breast cancer cell apoptosis by inhibiting FAS, which provide a basis for the development of xanthone as an agent for

  10. 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

    2016-01-01

    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. PMID:27477533

  11. Inhibition of prostaglandin E2 and interleukin 1-beta production by low-power laser irradiation in stretched human periodontal ligament cells.

    Science.gov (United States)

    Shimizu, N; Yamaguchi, M; Goseki, T; Shibata, Y; Takiguchi, H; Iwasawa, T; Abiko, Y

    1995-07-01

    It is well-known that orthodontic treatment usually causes some discomfort and pain to the patients. Recently, it has been reported that low-power laser irradiation is effective in reducing the pain accompanying tooth movement. However, the mechanism of such pain relief cannot be elucidated. Since high levels of prostaglandin (PG) E2 and interleukin (IL)-1 beta are found in the periodontal ligament (PDL) during tooth movement, and both factors are involved in the induction of pain, the effects of low-power laser irradiation on PGE2 and IL-1 beta production in stretched human PDL cells were studied in vitro. The PDL cells, derived from healthy premolars extracted for orthodontic treatment, were utilized for experiments. Cells were seeded in flexible-bottomed culture plates, and the bottom of each plate was elongated (18% increase) under vacuum at 6 cycles per min for 1, 3, or 5 days. The stretched cells were irradiated with a Ga-Al-As low-power diode laser (60 mW) once a day for 3, 6, or 10 min (from 10.8 to 36.0 J) for 1, 3, or 5 days. PGE2 and IL-1 beta levels in the medium were measured by radioimmunoassay. In response to mechanical stretching, human PDL cells showed a marked elevation in PGE2 production in a time-dependent manner. IL-1 beta production was also elevated, but this remained constant. The increase in PGE2 production was significantly inhibited by laser irradiation in a dose-dependent manner. The increase in IL-1 beta production was also significantly inhibited by laser irradiation, although the inhibition was only partial.(ABSTRACT TRUNCATED AT 250 WORDS)

  12. 15-Deoxy-Delta-12,14-Prostaglandin J2 Inhibits Lung Inflammation and Remodeling in Distinct Murine Models of Asthma

    Directory of Open Access Journals (Sweden)

    Diego S. Coutinho

    2017-06-01

    Full Text Available 15-deoxy-Δ-12,14-prostaglandin J2 (15d-PGJ2 has been described as an anti-inflammatory lipid mediator in several in vitro and in vivo studies, but its effect on allergic pulmonary inflammation remains elusive. The aim of this study was to investigate the therapeutic potential of 15d-PGJ2 based on distinct murine models of allergic asthma triggered by either ovalbumin (OVA or house dust mite extract (HDM. Characteristics of lung inflammation, airway hyper-reactivity (AHR, mucus exacerbation, and lung remodeling in sensitized A/J mice treated or not with 15d-PGJ2 were assessed. 15d-PGJ2 treatments were carried out systemically or topically given via subcutaneous injection or intranasal instillation, respectively. Analyses were carried out 24 h after the last allergen provocation. Irrespective of the route of administration, 15d-PGJ2 significantly inhibited the peribronchial accumulation of eosinophils and neutrophils, subepithelial fibrosis and also mucus exacerbation caused by either OVA or HDM challenge. The protective effect of 15d-PGJ2 occurred in parallel with inhibition of allergen-induced AHR and lung tissue production of pro-inflammatory cytokines, such as interleukin (IL-5, IL-13, IL-17, and TNF-α. Finally, 15d-PGJ2 was found effective in inhibiting NF-κB phosphorylation upon HDM challenge as measured by Western blotting. In conclusion, our findings suggest that 15d-PGJ2 can reduce crucial features of asthma, including AHR, lung inflammation, and remodeling in distinct murine models of the disease. These effects are associated with a decrease in lung tissue generation of pro-inflammatory cytokines by a mechanism related to downregulation of NF-κB phosphorylation.

  13. SELECTIVE INHIBITION OF HEPATITIS C VIRUS REPLICATION BY ALPHA-ZAM, A NIGELLA SATIVA SEED FORMULATION.

    Science.gov (United States)

    Oyero, Olufunmilayo G; Toyama, Masaaki; Mitsuhiro, Naoki; Onifade, Abdulfatah A; Hidaka, Akemi; Okamoto, Mika; Baba, Masanori

    2016-01-01

    Hepatitis C virus (HCV) infection became curable because of the development of direct acting antivirals (DAAs). However, the high cost of DAAs has greatly impeded their potential impact on the treatment of HCV infection. As a result, hepatitis C will continue to cause substantial morbidity, and mortality among chronically infected individuals in low and middle income countries. Thus, urgent need exists for developing cheaper drugs available to hepatitis C patients in these countries. Alpha-zam, an indigenous herbal formulation from Nigella sativa seed, was examined for its anti-HCV activity and cytotoxicity in genotype 1b HCV replicon cells. The antiviral activity was determined by luciferase expression and viral RNA synthesis, while the cytotoxicity was assessed by viable cell number and glyceraldehyde-3-phosphate dehydrogenase RNA synthesis in the replicon cells. Alpha-zam was found to be a selective inhibitor of HCV replication. The 50% effective dilution and 50% cytotoxic dilution of Alpha-zam were 761- and < 100-fold, respectively, in the subgenomic replicon cells LucNeo#2. Its selective inhibition of HCV was also confirmed by HCV RNA levels in LucNeo#2 and in the full-genome HCV replicon cells NNC#2 using real-time reverse transcriptase polymerase chain reaction. Furthermore, the anti-HCV activity of Alpha-zam was not due to the induction of interferon. Alpha-zam selectively inhibits HCV replication and therefore has potential for a novel antiviral agent against HCV infection.

  14. 15-Deoxy-Δ12,14-Prostaglandin J2 Inhibits Homing of Bone Marrow-Derived Mesenchymal Stem Cells Triggered by Chronic Liver Injury via Redox Pathway

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    Xin Liu

    2015-01-01

    Full Text Available It has been reported that bone marrow-derived mesenchymal stem cells (BMSCs have capacity to migrate to the damaged liver and contribute to fibrogenesis in chronic liver diseases. 15-Deoxy-Δ12,14-prostaglandin J2 (15d-PGJ2, an endogenous ligand for peroxisome proliferator-activated receptor gamma (PPARγ, is considered a new inhibitor of cell migration. However, the actions of 15d-PGJ2 on BMSC migration remain unknown. In this study, we investigated the effects of 15d-PGJ2 on the migration of BMSCs using a mouse model of chronic liver fibrosis and primary mouse BMSCs. Our results demonstrated that in vivo, 15d-PGJ2 administration inhibited the homing of BMSCs to injured liver by flow cytometric analysis and, in vitro, 15d-PGJ2 suppressed primary BMSC migration in a dose-dependent manner determined by Boyden chamber assay. Furthermore, the repressive effect of 15d-PGJ2 was blocked by reactive oxygen species (ROS inhibitor, but not PPARγ antagonist, and action of 15d-PGJ2 was not reproduced by PPARγ synthetic ligands. In addition, 15d-PGJ2 triggered a significant ROS production and cytoskeletal remodeling in BMSCs. In conclusion, our results suggest that 15d-PGJ2 plays a crucial role in homing of BMSCs to the injured liver dependent on ROS production, independently of PPARγ, which may represent a new strategy in the treatment of liver fibrosis.

  15. Bauer ketones 23 and 24 from Echinacea paradoxa var. paradoxa inhibit lipopolysaccharide-induced nitric oxide, prostaglandin E2 and cytokines in RAW264.7 mouse macrophages.

    Science.gov (United States)

    Zhang, Xiaozhu; Rizshsky, Ludmila; Hauck, Catherine; Qu, Luping; Widrlechner, Mark P; Nikolau, Basil J; Murphy, Patricia A; Birt, Diane F

    2012-02-01

    Among the nine Echinacea species, E. purpurea, E. angustifolia and E. pallida, have been widely used to treat the common cold, flu and other infections. In this study, ethanol extracts of these three Echinacea species and E. paradoxa, including its typical variety, E. paradoxa var. paradoxa, were screened in lipopolysaccharide (LPS)-stimulated macrophage cells to assess potential anti-inflammatory activity. E. paradoxa var. paradoxa, rich in polyenes/polyacetylenes, was an especially efficient inhibitor of LPS-induced production of nitric oxide (NO), prostaglandin E2 (PGE2), interleukin-1 beta (IL-1β) and interleukin-6 (IL-6) by 46%, 32%, 53% and 26%, respectively, when tested at 20 μg/ml in comparison to DMSO control. By bioactivity-guided fractionation, pentadeca-8Z-ene-11, 13-diyn-2-one (Bauer ketone 23) and pentadeca-8Z, 13Z-dien-11-yn-2-one (Bauer ketone 24) from E. paradoxa var. paradoxa were found primarily responsible for inhibitory effects on NO and PGE2 production. Moreover, Bauer ketone 24 was the major contributor to inhibition of inflammatory cytokine production in LPS-induced mouse macrophage cells. These results provide a rationale for exploring the medicinal effects of the Bauer ketone-rich taxon, E. paradoxa var. paradoxa, and confirm the anti-inflammatory properties of Bauer ketones 23 and 24. Copyright © 2011 Elsevier Ltd. All rights reserved.

  16. 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.

  17. Low concentrations of o,p'-DDT inhibit gene expression and prostaglandin synthesis by estrogen receptor-independent mechanism in rat ovarian cells.

    Directory of Open Access Journals (Sweden)

    Jing Liu

    Full Text Available o,p'-DDT is an infamous xenoestrogen as well as a ubiquitous and persistent pollutant. Biomonitoring studies show that women have been internally exposed to o,p'-DDT at range of 0.3-500 ng/g (8.46×10(-10 M-1.41×10(-6 M in blood and other tissues. However, very limited studies have investigated the biological effects and mechanism(s of o,p'-DDT at levels equal to or lower than current exposure levels in human. In this study, using primary cultures of rat ovarian granulosa cells, we determined that very low doses of o,p'-DDT (10(-12-10(-8 M suppressed the expression of ovarian genes and production of prostaglandin E2 (PGE2. In vivo experiments consistently demonstrated that o,p'-DDT at 0.5-1 mg/kg inhibited the gene expression and PGE2 levels in rat ovary. The surprising results from the receptor inhibitors studies showed that these inhibitory effects were exerted independently of either classical estrogen receptors (ERs or G protein-coupled receptor 30 (GPR30. Instead, o,p'-DDT altered gene expression or hormone action via inhibiting the activation of protein kinase A (PKA, rather than protein kinase C (PKC. We further revealed that o,p'-DDT directly interfered with the PKA catalytic subunit. Our novel findings support the hypothesis that exposure to low concentrations of o,p'-DDT alters gene expression and hormone synthesis through signaling mediators beyond receptor binding, and imply that the current exposure levels of o,p'-DDT observed in the population likely poses a health risk to female reproduction.

  18. Inhibition of thermolysin and human alpha-thrombin by cobalt(III) Schiff base complexes.

    Science.gov (United States)

    Takeuchi, T; Böttcher, A; Quezada, C M; Meade, T J; Gray, H B

    1999-05-01

    Cobalt(III) Schiff base complexes have been shown to inhibit the replication of the ocular herpes virus. It is well known that these complexes have a high affinity for nitrogenous donors such as histidine residues, and it is possible that they bind to (and inhibit) an enzyme that is crucial to viral replication. In model studies, we have found that [Co(acacen)(NH3)2]+ is an effective irreversible inhibitor of thermolysin at millimolar concentrations; it also inhibits human alpha-thrombin. Axial ligand exchange with an active-site histidine is the proposed mechanism of inhibition. The activity of thermolysin and thrombin can be protected by binding a reversible inhibitor to the active site before addition of the cobalt(III) complex.

  19. 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

  20. 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.

  1. 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.

  2. Inhibition of steroid 5 alpha-reductase by specific aliphatic unsaturated fatty acids.

    Science.gov (United States)

    Liang, T; Liao, S

    1992-01-01

    Human or rat microsomal 5 alpha-reductase activity, as measured by enzymic conversion of testosterone into 5 alpha-dihydrotestosterone or by binding of a competitive inhibitor, [3H]17 beta-NN-diethulcarbamoyl-4-methyl-4-aza-5 alpha-androstan-3-one ([3H]4-MA) to the reductase, is inhibited by low concentrations (less than 10 microM) of certain polyunsaturated fatty acids. The relative inhibitory potencies of unsaturated fatty acids are, in decreasing order: gamma-linolenic acid greater than cis-4,7,10,13,16,19-docosahexaenoic acid = cis-6,9,12,15-octatetraenoic acid = arachidonic acid = alpha-linolenic acid greater than linoleic acid greater than palmitoleic acid greater than oleic acid greater than myristoleic acid. Other unsaturated fatty acids such as undecylenic acid, erucic acid and nervonic acid, are inactive. The methyl esters and alcohol analogues of these compounds, glycerols, phospholipids, saturated fatty acids, retinoids and carotenes were inactive even at 0.2 mM. The results of the binding assay and the enzymic assay correlated well except for elaidic acid and linolelaidic acid, the trans isomers of oleic acid and linoleic acid respectively, which were much less active than their cis isomers in the binding assay but were as potent in the enzymic assay. gamma-Linolenic acid had no effect on the activities of two other rat liver microsomal enzymes: NADH:menadione reductase and glucuronosyl transferase. gamma-Linolenic acid, the most potent inhibitor tested, decreased the Vmax. and increased Km values of substrates, NADPH and testosterone, and promoted dissociation of [3H]4-MA from the microsomal reductase. gamma-Linolenic acid, but not the corresponding saturated fatty acid (stearic acid), inhibited the 5 alpha-reductase activity, but not the 17 beta-dehydrogenase activity, of human prostate cancer cells in culture. These results suggest that unsaturated fatty acids may play an important role in regulating androgen action in target cells. PMID:1637346

  3. Prostaglandins release plasma 'reciprocal coupling factor' in anaesthetized rats.

    Science.gov (United States)

    Hoult, J. R.; Moore, P. K.

    1981-01-01

    1. Prostaglandins E1, E2, I2 and endoperoxide analogue U46619 injected intra-arterially (i.a.) into anaesthetized rats at 2 micrograms/kg caused a substantial increase within 60 min of the plasma activity of prostaglandin 'reciprocal coupling factor' (RCF). RCF is the provisional name for the component(s) of plasma which inhibit microsomal prostaglandin synthesis and enhance cytosolic prostaglandin breakdown. 2. RCF is not released by inactive metabolite 13,14-dihydro-15-keto prostaglandin E2 (10 micrograms/kg, i.a.) or acetylcholine or histamine (2 micrograms/kg, i.a.). 3. We suggest that release by prostaglandins of RCF would provide the basis in vivo for a negative feedback mechanism controlling the activity of the prostaglandin system. PMID:7032632

  4. Low temperature stimulates alpha-melanophore-stimulating hormone secretion and inhibits background adaptation in Xenopus laevis.

    Science.gov (United States)

    Tonosaki, Y; Cruijsen, P M J M; Nishiyama, K; Yaginuma, H; Roubos, E W

    2004-11-01

    It is well-known that alpha-melanophore-stimulating hormone (alpha-MSH) release from the amphibian pars intermedia (PI) depends on the light condition of the animal's background, permitting the animal to adapt the colour of its skin to background light intensity. In the present study, we carried out nine experiments on the effect of low temperature on this skin adaptation process in the toad Xenopus laevis, using the skin melanophore index (MI) bioassay and a radioimmunoassay to measure skin colour adaptation and alpha-MSH secretion, respectively. We show that temperatures below 8 degrees C stimulate alpha-MSH secretion and skin darkening, with a maximum at 5 degrees C, independent of the illumination state of the background. No significant stimulatory effect of low temperature on the MI and alpha-MSH plasma contents was noted when the experiment was repeated with toads from which the neurointermediate lobe (NIL) had been surgically extirpated. This indicates that low temperature stimulates alpha-MSH release from melanotrope cells located in the PI. An in vitro superfusion study with the NIL demonstrated that low temperature does not act directly on the PI. A possible role of the central nervous system in cold-induced alpha-MSH release from the PI was tested by studying the hypothalamic expression of c-Fos (as an indicator for neuronal activity) and the coexistence of c-Fos with the regulators of melanotrope cell activity, neuropeptide Y (NPY) and thyrotrophin-releasing hormone (TRH), using double fluorescence immunocytochemistry. Upon lowering temperature from 22 degrees C to 5 degrees C, in white-adapted animals c-Fos expression decreased in NPY-producing suprachiasmatic-melanotrope-inhibiting neurones (SMIN) in the ventrolateral area of the suprachiasmatic nucleus (SC) but increased in TRH-containing neurones of the magnocellular nucleus. TRH is known to stimulate melanotrope alpha-MSH release. We conclude that temperatures around 5 degrees C inactivate the SMIN

  5. Inhibition of prostaglandin (PG) synthesis in sheep vesicular gland microsomes (SVGM) by nitroblue tetrazolium (NBT) and vitamin E (VE).

    Science.gov (United States)

    Rao, G H; Burris, S M; Gerrard, J M; White, J G

    1979-02-01

    Previous studies have shown that NBT and VE together are potent inhibitors of platelet aggregation, secretion and PG synthesis. In this study, we evaluated the capacity of NBT to detect PG synthesis by SVGM. Aspirin pretreatment of SVGM decreased the amount of NBT reduced after addition of arachidonic acid, demonstrating that products generated by the cyclo-oxygenase were involved in NBT reduction. The influence of NBT and VE on PG synthesis by SVGM was then evaluated by measuring malondialdehyde (MDA) production. NBT or VE alone had no significant effect, but together these agents were as effective as aspirin in preventing MDA formation. The effect of NBT and VE on 14C-arachidonic acid conversion was followed by thin layer chromatography and radioscanning. Again, NBT or VE alone were ineffective, whereas the combination was as effective as aspirin in preventing conversion of arachidonic acid. We speculate NBT and VE together inhibit pg synthesis by scavenging a free radical species of arachidonic acid generated in the initial step of fatty acid peroxidation.

  6. 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

    Hypoxia-inducible factor-1 (HIF-1) is a transcription factor that plays a critical role in angiogenesis, survival, metastasis, drug resistance, and glucose metabolism. Elevated expression of the alpha-subunit of HIF-1 (HIF-1alpha), which occurs in response to hypoxia or activation of growth factor...... 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......-regulation of endogenous HIF-1alpha and vascular endothelial growth factor in the liver. The effect can last for days after administration of single dose of EZN-2968 and is associated with long residence time of locked nucleic acid in certain tissues. In efficacy studies, tumor reduction was found in nude mice implanted...

  7. 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.

  8. 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

  9. 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

  10. 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.

  11. 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

    and atherosclerosis. To test this hypothesis, we performed three experiments in which eight healthy males either rested (CON), rode a bicycle for 3 h (EX), or were infused with recombinant human IL-6 (rhIL-6) for 3 h while they rested. After 2.5 h, the volunteers received a bolus of Escherichia coli...... 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...

  12. Itch: Role of Prostaglandins

    Science.gov (United States)

    Greaves, Malcolm W.; McDonald-Gibson, Wendy

    1973-01-01

    Prostaglandin E1 lowers the threshold of human skin to histamine-evoked itching. Though histamine and other mediators may produce itching by a direct action, itching in inflamed skin can also be explained by a pharmacological synergism in which low concentrations of prostaglandins, which do not themselves cause itching, potentiate itching due to histamine and possibly other agents. Alteration of threshold responses of components of inflammation to other mediators may be an important general role of prostaglandins. PMID:4755182

  13. Alpha-amylase inhibitor-1 gene from Phaseolus vulgaris expressed in Coffea arabica plants inhibits alpha-amylases from the coffee berry borer pest.

    Science.gov (United States)

    Barbosa, Aulus E A D; Albuquerque, Erika V S; Silva, Maria C M; Souza, Djair S L; Oliveira-Neto, Osmundo B; Valencia, Arnubio; Rocha, Thales L; Grossi-de-Sa, Maria F

    2010-06-17

    Coffee is an important crop and is crucial to the economy of many developing countries, generating around US$70 billion per year. There are 115 species in the Coffea genus, but only two, C. arabica and C. canephora, are commercially cultivated. Coffee plants are attacked by many pathogens and insect-pests, which affect not only the production of coffee but also its grain quality, reducing the commercial value of the product. The main insect-pest, the coffee berry borer (Hypotheneumus hampei), is responsible for worldwide annual losses of around US$500 million. The coffee berry borer exclusively damages the coffee berries, and it is mainly controlled by organochlorine insecticides that are both toxic and carcinogenic. Unfortunately, natural resistance in the genus Coffea to H. hampei has not been documented. To overcome these problems, biotechnological strategies can be used to introduce an alpha-amylase inhibitor gene (alpha-AI1), which confers resistance against the coffee berry borer insect-pest, into C. arabica plants. We transformed C. arabica with the alpha-amylase inhibitor-1 gene (alpha-AI1) from the common bean, Phaseolus vulgaris, under control of the seed-specific phytohemagglutinin promoter (PHA-L). The presence of the alpha-AI1 gene in six regenerated transgenic T1 coffee plants was identified by PCR and Southern blotting. Immunoblotting and ELISA experiments using antibodies against alpha-AI1 inhibitor showed a maximum alpha-AI1 concentration of 0.29% in crude seed extracts. Inhibitory in vitro assays of the alpha-AI1 protein against H. hampei alpha-amylases in transgenic seed extracts showed up to 88% inhibition of enzyme activity. This is the first report showing the production of transgenic coffee plants with the biotechnological potential to control the coffee berry borer, the most important insect-pest of crop coffee.

  14. BIOLOGICAL ACTIVITIES AFFORDED BY THE EXTRACT FROM RARU BARK TO INHIBIT ACTION OF ALPHA- GLUCOSIDASE ENZYMES

    Directory of Open Access Journals (Sweden)

    Gunawan Pasaribu

    2011-06-01

    Full Text Available Raru (Shoreabalanocarpoides Sym signifies one of the tree species that grows widespread in Sumatra Island.  Its bark portion is commonly used by local villagers as additional ingredient mixed to nira (sugar palm juice.  This addition is intended to make the juice more durable and also to enrich its taste after the juice is previously fermented to become traditional toddy beverage or the so-call “tuak”.  Local villagers believe that raru bark can reduce the level of blood sugar. As the relevance, the research was conducted to confirm that the extract from raru bark could afford its biological activities to inhibit alpha-glucosidase enzyme through its characterization, quantification, and isolation of its boactive compound. The extraction was performed using two methods (i.e.reflux and maceration techniques. Result revealed that the bark extract obtained from both techniques contained polyphenol compounds: flavonoid, saponin and tannin. Further, raru-bark extract from the reflux and maceration techniques could inhibit the action of alpha glucosidase enzymes on carbohydrate substrate ( i.e. p -nitrophenil-α-D-glucopyranose, at respectively 90.67% and 97.33%. Meanwhile, the inhibition activities afforded by the patented drug as a control (i.e. glucobay equaled to 97.05%.  Assesment using UV-VIS spectroscopy, showed that the maximum spectrum of bioactive compound in the extract was at the wave length of 288.6 nm. Scrutiny using FTIR spectroscopy could identif y the presence of aromatic groups in the compound, containing -OH, C-H, C=C, C-O and C-H bond types. Analysis using GC-MS exhibited that the compound had molecular weight of 390 with molecular structure as C20H22O8. Ultimately, data analysis scrutiny with the aid of NMR judged the most plausible compound as bioactive was 4-Glucosyl-3, 4’, 5-trihydroxystilbene.

  15. Alpha-amylase Inhibition and Antioxidant Activity of Marine Green Algae and its Possible Role in Diabetes Management.

    Science.gov (United States)

    Unnikrishnan, P S; Suthindhiran, K; Jayasri, M A

    2015-10-01

    In the continuing search for safe and efficient antidiabetic drug, marine algae become important source which provide several compounds of immense therapeutic potential. Alpha-amylase, alpha-glucosidase inhibitors, and antioxidant compounds are known to manage diabetes and have received much attention recently. In the present study, four green algae (Chaetomorpha aerea, Enteromorpha intestinalis, Chlorodesmis, and Cladophora rupestris) were chosen to evaluate alpha-amylase, alpha-glucosidase inhibitory, and antioxidant activity in vitro. The phytochemical constituents of all the extracts were qualitatively determined. Antidiabetic activity was evaluated by inhibitory potential of extracts against alpha-amylase and alpha-glucosidase by spectrophotometric assays. Antioxidant activity was determined by 2,2-diphenyl-1-picrylhydrazyl, hydrogen peroxide (H2O2), and nitric oxide scavenging assay. Gas chromatography-mass spectrometry (GC-MS) analysis was carried out to determine the major compound responsible for its antidiabetic action. Among the various extracts screened, chloroform extract of C. aerea (IC50 - 408.9 μg/ml) and methanol extract of Chlorodesmis (IC50 - 147.6 μg/ml) showed effective inhibition against alpha-amylase. The extracts were also evaluated for alpha-glucosidase inhibition, and no observed activity was found. Methanol extract of C. rupestris showed notable free radical scavenging activity (IC50 - 666.3 μg/ml), followed by H2O2 (34%) and nitric oxide (49%). Further, chemical profiling by GC-MS revealed the presence of major bioactive compounds. Phenol, 2,4-bis (1,1-dimethylethyl) and z, z-6,28-heptatriactontadien-2-one were predominantly found in the methanol extract of C. rupestris and chloroform extract of C. aerea. Our results demonstrate that the selected algae exhibit notable alpha-amylase inhibition and antioxidant activity. Therefore, characterization of active compounds and its in vivo assays will be noteworthy. Four green algae were

  16. 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.

  17. Diosmetin inhibits the expression of alpha-hemolysin in Staphylococcus aureus.

    Science.gov (United States)

    Liu, Shui; Zhou, Xuan; Li, Wenhua; Zhang, Hong; Zhang, Bing; Li, Gen; Liu, Bowen; Deng, Xuming; Peng, Liping

    2015-08-01

    Staphylococcus aureus is a significant human pathogen that causes a wide range of diseases. Alpha-hemolysin (Hla), a pore-forming cytotoxin that is produced by most S. aureus strains, can cause tissue injury and plays a critical role in the virulence of this pathogen. In the present study, we discovered that diosmetin, a natural flavonoid that occurs primarily in citrus fruits and exhibits little anti-S. aureus activity, could diminish the production of Hla in culture supernatants in a concentration-dependent manner. The analysis of cytotoxicity in the co-culture system of S. aureus and A549 epithelial cells showed that such inhibition confers significant protection against S. aureus-mediated injury. Our results suggested that diosmetin has the potential to be a new anti-virulence drug for S. aureus infection, particularly for the targeting of Hla.

  18. Prostaglandin F2alpha- and FAS-activating antibody-induced regression of the corpus luteum involves caspase-8 and is defective in caspase-3 deficient mice

    Directory of Open Access Journals (Sweden)

    Flavell Richard A

    2003-02-01

    Full Text Available Abstract We recently demonstrated that caspase-3 is important for apoptosis during spontaneous involution of the corpus luteum (CL. These studies tested if prostaglandin F2α (PGF2α or FAS regulated luteal regression, utilize a caspase-3 dependent pathway to execute luteal cell apoptosis, and if the two receptors work via independent or potentially shared intracellular signaling components/pathways to activate caspase-3. Wild-type (WT or caspase-3 deficient female mice, 25–26 days old, were given 10 IU equine chorionic gonadotropin (eCG intraperitoneally (IP followed by 10 IU human chorionic gonadotropin (hCG IP 46 h later to synchronize ovulation. The animals were then injected with IgG (2 micrograms, i.v., the FAS-activating antibody Jo2 (2 micrograms, i.v., or PGF2α (10 micrograms, i.p. at 24 or 48 h post-ovulation. Ovaries from each group were collected 8 h later for assessment of active caspase-3 enzyme and apoptosis (measured by the TUNEL assay in the CL. Regardless of genotype or treatment, CL in ovaries collected from mice injected 24 h after ovulation showed no evidence of active caspase-3 or apoptosis. However, PGF2α or Jo2 at 48 h post-ovulation and collected 8 h later induced caspase-3 activation in 13.2 ± 1.8% and 13.7 ± 2.2 % of the cells, respectively and resulted in 16.35 ± 0.7% (PGF2α and 14.3 ± 2.5% TUNEL-positive cells when compared to 1.48 ± 0.8% of cells CL in IgG treated controls. In contrast, CL in ovaries collected from caspase-3 deficient mice whether treated with PGF2α , Jo2, or control IgG at 48 h post-ovulation showed little evidence of active caspase-3 or apoptosis. CL of WT mice treated with Jo2 at 48 h post-ovulation had an 8-fold increase in the activity of caspase-8, an activator of caspase-3 that is coupled to the FAS death receptor. Somewhat unexpectedly, however, treatment of WT mice with PGF2α at 48 h post-ovulation resulted in a 22-fold increase in caspase-8 activity in the CL, despite the fact

  19. Inhibition of DNA replication, DNA repair synthesis, and DNA polymerases. cap alpha. and delta by butylphenyl deoxyguanosine triphosphate

    Energy Technology Data Exchange (ETDEWEB)

    Dreslor, S.L.; Frattini, M.G.

    1987-05-01

    Semiconservative DNA replication in growing mammalian cells and ultraviolet (UV)-induced DNA repair synthesis in nongrowing mammalian cells are mediated by one or both of the aphidicolin-sensitive DNA polymerases, ..cap alpha.. and/or delta. They have studied the inhibition of replication and repair synthesis in permeable human cells by N/sup 2/ (p-n-butylphenyl)-2'-deoxyguanosine-5'-triphosphate (BuPh dGTP), an agent which inhibits polymerase ..cap alpha.. strongly and polymerase delta weakly. Both processes are inhibited by BuPh-dGTP in competition with dGTP. The K/sub i/'s are, for replication, 2-3 ..mu..M and, for repair synthesis, 3-4 ..mu..M, consistent with the involvement of the same DNA polymerase in both processes. Inhibition of isolated human polymerase ..cap alpha.. by BuPh-dGTP is also competitive with dGTP, but the K/sub i/ is approximately 10 nM, several hundred-fold lower than the K/sub i/'s of replication and repair synthesis. Isolated polymerase delta is inhibited by BuPh-dGTP at doses similar to those which inhibit replication and repair synthesis, however, attempts to determine the K/sub i/ of polymerase delta were hampered by the finding that the dependence of delta activity on deoxyribunucleotide concentration is parabolic at low doses. This behavior differs from the behavior of polymerase ..cap alpha.. and of cellular DNA replication and repair synthesis, all of which show a simple, hyperbolic relationship between activity and deoxyribonucleotide concentration. Thus, inhibition of DNA replication and UV induced DNA repair synthesis by BuPh dGTP is quantitatively similar to DNA polymerase delta, but some other characteristics of the cellular processes are more similar to those of polymerase ..cap alpha...

  20. Neurotensin agonists block the prepulse inhibition deficits produced by a 5-HT2A and an alpha1 agonist.

    Science.gov (United States)

    Shilling, P D; Melendez, G; Priebe, K; Richelson, E; Feifel, D

    2004-09-01

    Neurotensin (NT) agonists have been proposed as potential antipsychotics based exclusively upon their ability to inhibit dopamine-2 (D2) receptor transmission. Several other pharmacological mechanisms have been implicated in enhancing the antipsychotic profile produced by D2 inhibition alone. These include inhibition of 5-HT2A and alpha1-adrenoceptors. Recently, we reported that systemic administration of the neurotensin agonist PD149163 blocks deficits in prepulse inhibition (PPI) of the startle reflex produced by the 5-HT2A receptor agonist DOI. This suggested that NT agonists could inhibit 5-HT2A modulation of neurotransmission. To determine if other peripherally administered NT agonists shared this effect, we examined the effects of NT69L, another NT agonist, on DOI-induced PPI deficits. In addition, to determine if NT agonists also inhibit alpha1-adrenoceptor neurotransmission, we examined the effects of PD149163 and NT69L on PPI deficits induced by the alpha1-adrenoceptor agonist, cirazoline. In the NT69L/DOI study, rats received subcutaneous (SC) injections of NT69L (0, 0.1, 1, or 2 mg/kg) followed 30 min later by SC saline or DOI (0.5 mg/kg). In the NT agonist/cirazoline studies, animals received SC injections of either PD149163 (0, 0.01, 0.1, or 1 mg/kg) or NT69L (0, 0.01, 0.1, or 1 mg/kg) followed 30 min later by SC saline or cirazoline (0.7 mg/kg). Animals were tested in startle chambers 20 min later. In all three experiments the PPI disruption produced by DOI and cirazoline was blocked by the NT agonists. These findings provide strong evidence that NT agonists inhibit 5-HT2A and alpha1-adrenoceptor modulation of neurotransmission, pharmacological effects that, in conjunction with their known inhibition of dopamine transmission, strengthen the antipsychotic potential of NT agonists.

  1. Alpha 1 Antitrypsin Inhibits Dendritic Cell Activation and Attenuates Nephritis in a Mouse Model of Lupus.

    Directory of Open Access Journals (Sweden)

    Ahmed S Elshikha

    Full Text Available Systemic lupus erythematosus (SLE is an autoimmune disorder with a worldwide distribution and considerable mortality and morbidity. Although the pathogenesis of this disease remains elusive, over-reactive dendritic cells (DCs play a critical role in the disease development. It has been shown that human alpha-1 antitrypsin (hAAT has protective effects in type 1 diabetes and rheumatoid arthritis mouse models. In the present study, we tested the effect of AAT on DC differentiation and functions, as well as its protective effect in a lupus-prone mouse model. We showed that hAAT treatment significantly inhibited LPS (TLR4 agonist and CpG (TLR9 agonist -induced bone-marrow (BM-derived conventional and plasmacytoid DC (cDC and pDC activation and reduced the production of inflammatory cytokines including IFN-I, TNF-α and IL-1β. In MRL/lpr mice, hAAT treatment significantly reduced BM-derived DC differentiation, serum autoantibody levels, and importantly attenuated renal pathology. Our results for the first time demonstrate that hAAT inhibits DC activation and function, and it also attenuates autoimmunity and renal damage in the MRL/lpr lupus model. These results imply that hAAT has a therapeutic potential for the treatment of SLE in humans.

  2. Role of the ERC motif in the proximal part of the second intracellular loop and the C-terminal domain of the human prostaglandin F2alpha receptor (hFP-R) in G-protein coupling control.

    Science.gov (United States)

    Pathe-Neuschäfer-Rube, Andrea; Neuschäfer-Rube, Frank; Püschel, Gerhard P

    2005-05-15

    The human FP-R (F2alpha prostaglandin receptor) is a Gq-coupled heptahelical ectoreceptor, which is of significant medical interest, since it is a potential target for the treatment of glaucoma and preterm labour. On agonist exposure, it mediates an increase in intracellular inositol phosphate formation. Little is known about the structures that govern the agonist-dependent receptor activation. In other prostanoid receptors, the C-terminal domain has been inferred in the control of agonist-dependent receptor activation. A DRY motif at the beginning of the second intracellular loop is highly conserved throughout the G-protein-coupled receptor family and appears to be crucial for controlling agonist-dependent receptor activation. It is replaced by an ERC motif in the FP-R and no evidence for the relevance of this motif in ligand-dependent activation of prostanoid receptors has been provided so far. The aim of the present study was to elucidate the potential role of the C-terminal domain and the ERC motif in agonist-controlled intracellular signalling in FP-R mutants generated by site-directed mutagenesis. It was found that substitution of the acidic Glu(132) in the ERC motif by a threonine residue led to full constitutive activation, whereas truncation of the receptor's C-terminal domain led to partial constitutive activation of all three intracellular signal pathways that had previously been shown to be activated by the FP-R, i.e. inositol trisphosphate formation, focal adhesion kinase activation and T-cell factor signalling. Inositol trisphosphate formation and focal adhesion kinase phosphorylation were further enhanced by ligand binding in cells expressing the truncation mutant but not the E132T (Glu132-->Thr) mutant. Thus C-terminal truncation appeared to result in a receptor with partial constitutive activation, whereas substitution of Glu132 by threonine apparently resulted in a receptor with full constitutive activity.

  3. Inhibition of [11C]mirtazapine binding by alpha2-adrenoceptor antagonists studied by positron emission tomography in living porcine brain

    DEFF Research Database (Denmark)

    Smith, Donald F; Dyve, Suzan; Minuzzi, Luciano

    2006-01-01

    Inhibition of [11C]mirtazapine binding by alpha2-adrenoceptor antagonists studied by positron emission tomography in living porcine brain......Inhibition of [11C]mirtazapine binding by alpha2-adrenoceptor antagonists studied by positron emission tomography in living porcine brain...

  4. 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...

  5. Identification of SNARE complex modulators that inhibit exocytosis from an alpha-helix-constrained combinatorial library.

    Science.gov (United States)

    Blanes-Mira, Clara; Pastor, Maria T; Valera, Elvira; Fernández-Ballester, Gregorio; Merino, Jaime M; Gutierrez, Luis M; Perez-Payá, Enrique; Ferrer-Montiel, Antonio

    2003-01-01

    Synthetic peptides patterned after the proteins involved in vesicle fusion [the so-called SNARE (soluble N -ethylmaleimide-sensitive fusion protein attachment protein receptor) proteins] are potent inhibitors of SNARE complex assembly and neuronal exocytosis. It is noteworthy that the identification of peptide sequences not related to the SNARE proteins has not been accomplished yet; this is due, in part, to the structural constraints and the specificity of the protein interactions that govern the formation of the SNARE complex. Here we have addressed this question and used a combinatorial approach to identify peptides that modulate the assembly of the SNARE core complex and inhibit neuronal exocytosis. An alpha-helix-constrained, mixture-based, 17-mer combinatorial peptide library composed of 137180 sequences was synthesized in a positional scanning format. Peptide mixtures were assayed for their ability to prevent the formation of the in vitro -reconstituted SDS-resistant SNARE core complex. Library deconvolution identified eight peptides that inhibited the assembly of the SNARE core complex. Notably, the most potent 17-mer peptide (acetyl-SAAEAFAKLYAEAFAKG-NH2) abolished both Ca2+-evoked catecholamine secretion from detergent-permeabilized chromaffin cells and L-glutamate release from intact hippocampal primary cultures. Collectively, these findings indicate that amino acid sequences that prevent SNARE complex formation are not restricted to those that mimic domains of SNARE proteins, thus expanding the diversity of molecules that target neuronal exocytosis. Because of the implication of neurosecretion in the aetiology of several human neurological disorders, these newly identified peptides may be considered hits for the development of novel anti-spasmodic drugs. PMID:12852787

  6. 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. PMID:28367491

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

    Directory of Open Access Journals (Sweden)

    Sunday O. Oyedemi

    2017-01-01

    Full Text Available 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.

  8. 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.

  9. Imperatorin inhibits the expression of alpha-hemolysin in Staphylococcus aureus strain BAA-1717 (USA300).

    Science.gov (United States)

    Ouyang, Ping; Chen, Junjie; Sun, Mao; Yin, Zhongqiong; Lin, Juchun; Fu, Hualin; Shu, Gang; He, Changliang; Lv, Cheng; Deng, Xuming; Wang, Kaiyu; Geng, Yi; Yin, Lizi

    2016-07-01

    Both community-associated and hospital-acquired infections with methicillin-resistant Staphylococcus aureus (MRSA) have been increasingly reported around the world in the past 20 years. In 2006, the Centers for Disease Control and Prevention reported that 64 % of MRSA isolates were of the USA300 clonal type in infected patients in USA. The aim of our study was to estimate the in vitro effect of imperatorin on MRSA strain BAA-1717 (USA300). The effects of imperatorin on alpha-hemolysin (Hla) production, when strain BAA-1717 was co-cultured with sub-inhibitory concentrations of imperatorin, were analysed using susceptibility testing, hemolysis assays, western blotting and real-time PCR. Live/Dead analysis and cytotoxicity assays were employed to examine the protective effect of imperatorin against the strain BAA-1717-mediated injury of human alveolar epithelial cells (A549). The results showed that imperatorin has no anti-S. aureus activity at the tested concentrations in vitro. However, imperatorin can observably inhibit the production of Hla in culture supernatants and reduce the transcriptional levels of hla (the gene encoding Hla) and arg (the accessory gene regulator). Imperatorin prevented Hla-mediated A549 epithelial cell injury in a co-culture system. In conclusion, our results suggested that imperatorin has the potential to be developed as a new anti-virulence drug candidate for managing S. aureus infection.

  10. Use of RNA interference to inhibit integrin (alpha6beta4)-mediated invasion and migration of breast carcinoma cells.

    Science.gov (United States)

    Lipscomb, Elizabeth A; Dugan, Aisling S; Rabinovitz, Isaac; Mercurio, Arthur M

    2003-01-01

    The application of small interfering RNA (siRNA) oligonucleotides to silence gene expression has profound implications for the intervention of human diseases including cancer. Using this technique, we explored the possibility that the alpha6beta4 integrin, a laminin adhesion receptor with a recognized role in the invasive phenotype of many carcinomas, represents a potential therapeutic target to inhibit the migration and invasion of carcinoma cells. We found that siRNA oligonucleotides targeted to either subunit of the alpha6beta4 integrin reduced cell surface expression of this integrin and resulted in decreased invasion of MDA-MB-231 breast carcinoma cells. Interestingly, reduced alpha6beta4 expression also promoted decreased migration on non-laminin substrata indicating that this integrin can function in a ligand-independent manner. In addition, the absence of beta4 expression in these cells augmented the formation of alpha6beta1 heterodimers and increased adhesion to laminin-1. Taken together, these results substantiate the importance of the alpha6beta4 integrin in invasion and migration that has been demonstrated previously by expression of the beta4 subunit in beta4-deficient cell lines and by function blocking antibodies. Furthermore, these data suggest that the utilization of siRNA oligonucleotides to reduce the expression of the alpha6beta4 integrin may be a useful approach to prevent carcinoma cell progression.

  11. Inhibition of systemic inflammation by central action of the neuropeptide alpha-melanocyte- stimulating hormone.

    Science.gov (United States)

    Delgado Hernàndez, R; Demitri, M T; Carlin, A; Meazza, C; Villa, P; Ghezzi, P; Lipton, J M; Catania, A

    1999-01-01

    The neuropeptide alpha-melanocyte stimulating hormone (alpha-MSH) reduces fever and acute inflammation in the skin when administered centrally. The aim of the present research was to determine whether central alpha-MSH can also reduce signs of systemic inflammation in mice with endotoxemia. Increases in serum tumor necrosis factor-alpha and nitric oxide, induced by intraperitoneal administration of endotoxin, were modulated by central injection of a small concentration of alpha-MSH. Inducible nitric oxide synthase (iNOS) activity and iNOS mRNA in lungs and liver were likewise modulated by central alpha-MSH. Lung myeloperoxidase activity, a marker of neutrophil infiltration, was increased in endotoxemic mice; the increase was significantly less in lungs of mice treated with central alpha-MSH. Intraperitoneal administration of the small dose of alpha-MSH that was effective centrally did not alter any of the markers of inflammation. In experiments using immunoneutralization of central alpha-MSH, we tested the idea that endogenous peptide induced within the brain during systemic inflammation modulates host responses to endotoxic challenge in peripheral tissues. The data showed that proinflammatory agents induced by endotoxin in the circulation, lungs, and liver were significantly greater after blockade of central alpha-MSH. The results suggest that anti-inflammatory influences of neural origin that are triggered by alpha-MSH could be used to treat systemic inflammation.

  12. Anti-inflammatory activity of 6-hydroxy-2,7-dimethoxy-1,4-henanthraquinone from tuberous roots of yam (Dioscorea batatas) through inhibition of prostaglandin D₂ and leukotriene C₄ production in mouse bone marrow-derived mast cells.

    Science.gov (United States)

    Jin, Meihua; Lu, Yue; Yang, Ju Hye; Jo, Tae Hyung; Park, Young In; Lee, Chong-Kil; Park, Sang-Jo; Son, Kun Ho; Chang, Hyeun Wook

    2011-09-01

    6-Hydroxy-2,7-dimethoxy-1,4-phenanthraquinone (PAQ) isolated from the tuberous roots of Yam (Dioscorea batatas) inhibited cyclooxygenase-2 (COX-2) and cyclooxygenase-1 (COX-1) dependent prostaglandin D(2) (PGD(2)) generation in mouse bone marrow-derived mast cells in a concentration-dependent manner with IC(50) values of 0.08 μM and 0.27 μM, respectively. In the Western blotting with specific anti-COX-2 antibodies, the decrease of the quantity of PGD(2) was accompanied by a decrease in the COX-2 protein level. But PAQ did not affect COX-1 protein level. In addition, this compound inhibited 5-lipoxygenase (5-LOX) dependent production of leukotriene C(4) in a dose-dependent manner, with an IC(50) of 0.032 μM. These results demonstrate that PAQ has a dual COX-2/5-LOX inhibitory activity. This compound also inhibited the degranulation reaction in a dose-dependent manner with an IC(50) of 2.7 μM. Thus, these results suggest that PAQ may be useful in regulating mast cell-mediated inflammatory diseases.

  13. Altered aortic and cremaster muscle prostaglandin synthesis in diabetic rats

    International Nuclear Information System (INIS)

    Myers, T.O.; Messina, E.J.; Rodrigues, A.M.; Gerritsen, M.E.

    1985-01-01

    Alterations in the synthesis and release of prostaglandins have been reported in humans and animal models of diabetes mellitus. In the present study synthesis and release of prostaglandins by thoracic aorta and cremaster muscle of rats with streptozotocin-induced diabetes of 8 wk duration was compared with age-matched controls. Prostaglandin synthesis was assessed by the measurement of immunoreactive prostaglandin E2 (PGE2) and 6-ketoprostaglandin F1 alpha (6-keto-PGF1 alpha) release and by quantifying metabolism of exogenous [1- 14 C]arachidonic acid by thoracic aortic rings and minced cremaster muscle. These studies indicate that diminished prostacyclin (PGI2) and/or PGE2 production is not a general feature of all diabetic vascular tissues, suggesting that large and small blood vessels may not be similarly affected by diabetes in regard to the metabolism of exogenous arachidonic acid and the synthesis and release of prostaglandins. Furthermore, the vascular changes often observed in conjunction with diabetes, i.e., alterations in vascular reactivity and microangiopathy in small blood vessels and atherosclerosis of large blood vessels may be related in some way to the segmental differences observed in prostaglandin synthesis

  14. Stimulation of prostaglandin synthesis in rat cerebral cortex via a beta-adrenoceptor.

    Science.gov (United States)

    Hillier, K; Templeton, W W

    1982-01-01

    1. Synthesis of prostaglandin E2 (PGE2) and prostaglandin F2 alpha (PGF2 alpha) in rat cerebral cortex slices is increased by beta-adrenoceptor agonists. 2. Phenylephrine, an alpha-adrenoceptor agonist, has no effect while oxymetazoline increased PGF2 alpha only. 3. PG synthesis stimulation by noradrenaline (NA) was prevented by beta- but not by alpha-adrenoceptor antagonists. 4. Dibutyryl cyclic AMP and inhibitors of cyclic nucleotide phosphodiesterase augment PG synthesis. 5. Stimulation of PG synthesis in rat cerebral cortex by NA is mediated by a beta-adrenoceptor.

  15. Low temperature stimulates alpha-melanophore-stimulating hormone secretion and inhibits background adaptation in Xenopus laevis.

    NARCIS (Netherlands)

    Tonosaki, Y; Cruijsen, P.M.; Nishiyama, K; Yaginuma, H; Roubos, E.W.

    2004-01-01

    It is well-known that alpha-melanophore-stimulating hormone (alpha-MSH) release from the amphibian pars intermedia (PI) depends on the light condition of the animal's background, permitting the animal to adapt the colour of its skin to background light intensity. In the present study, we carried out

  16. Prostaglandin E1 and Its Analog Misoprostol Inhibit Human CML Stem Cell Self-Renewal via EP4 Receptor Activation and Repression of AP-1.

    Science.gov (United States)

    Li, Fengyin; He, Bing; Ma, Xiaoke; Yu, Shuyang; Bhave, Rupali R; Lentz, Steven R; Tan, Kai; Guzman, Monica L; Zhao, Chen; Xue, Hai-Hui

    2017-09-07

    Effective treatment of chronic myelogenous leukemia (CML) largely depends on the eradication of CML leukemic stem cells (LSCs). We recently showed that CML LSCs depend on Tcf1 and Lef1 factors for self-renewal. Using a connectivity map, we identified prostaglandin E1 (PGE1) as a small molecule that partly elicited the gene expression changes in LSCs caused by Tcf1/Lef1 deficiency. Although it has little impact on normal hematopoiesis, we found that PGE1 treatment impaired the persistence and activity of LSCs in a pre-clinical murine CML model and a xenograft model of transplanted CML patient CD34 + stem/progenitor cells. Mechanistically, PGE1 acted on the EP4 receptor and repressed Fosb and Fos AP-1 factors in a β-catenin-independent manner. Misoprostol, an FDA-approved EP4 agonist, conferred similar protection against CML. These findings suggest that activation of this PGE1-EP4 pathway specifically targets CML LSCs and that the combination of PGE1/misoprostol with conventional tyrosine-kinase inhibitors could provide effective therapy for CML. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. 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.

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

    Science.gov (United States)

    Rahimzadeh, Mahsa; Jahanshahi, Samaneh; Moein, Soheila; Moein, Mahmood Reza

    2014-06-01

    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. 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. Both plant extracts showed time and concentration dependent inhibition of α-amylase. 60% inhibition was seen with 2 mg/ml of U. dioica and 0.4 mg/ml of J. regia aqueous extract. Dixon plots revealed the type of α-amylase inhibition by these two extracts as competitive inhibition. Determination of the type of α-amylase inhibition by these plant extracts could provide by successful use of plant chemicals as drug targets.

  19. Prostaglandin F2α-induced luteolysis involves activation of Signal transducer and activator of transcription 3 and inhibition of AKT signaling in cattle.

    Science.gov (United States)

    Rovani, Monique T; Ilha, Gustavo F; Gasperin, Bernardo G; Nóbrega, Jandui E; Siddappa, Dayananda; Glanzner, Werner G; Antoniazzi, Alfredo Q; Bordignon, Vilceu; Duggavathi, Raj; Gonçalves, Paulo B D

    2017-06-01

    Prostaglandin F2α (PGF) induces the precipitous loss of steroidogenic capabilities and cellular death in the corpus luteum of many species, yet the molecular mechanisms underlying this event are not completely understood. Signal transducer and activator of transcription 3 (STAT3) was activated in granulosa cells during follicle atresia, whereas AKT is immediately down-regulated in the corpus luteum after PGF treatment in cattle; however, their involvement in both functional and morphological luteolysis in monovular species still need to be determined. Blood samples and corpus lutea were collected from cows before (0) and 2, 12, 24, and 48 hr after PGF treatment on Day 10 of the estrous cycle (4-5 cows per time point). Serum progesterone concentrations decreased by threefold (p < 0.05) within 2 hr, confirming functional luteolysis. The mRNA abundance of the pro-apoptotic gene BAX increased 12-48 hr post-PGF treatment (p < 0.05), while morphological luteolysis was observed 24 and 48 hr after PGF treatment, based on the loss of plasma membrane integrity, reduction of cytoplasmic volume, and pyknotic nuclei. Phosphorylated STAT3 increased, peaking at 12 hr, and remained elevated until 48 hr after PGF treatment. SOCS3 transcript abundance also increased (p < 0.05) starting at 2 hr post-PGF treatment. In contrast, AKT phosphorylation decreased by 12 hr after treatment. Thus, activation of STAT3 and inactivation of AKT signaling are involved in structural regression of the corpus luteum. © 2017 Wiley Periodicals, Inc.

  20. Inhibition of gastric acid secretion by epidermal growth factor. Effects on cyclic AMP and on prostaglandin production in rat isolated parietal cells.

    OpenAIRE

    Hatt, J F; Hanson, P J

    1988-01-01

    Histamine (0.5 mM) stimulated the cyclic AMP content of cell suspensions containing greater than 80% parietal cells. Epidermal growth factor (EGF) inhibited this stimulatory effect of histamine, but had no effect on basal cyclic AMP content. The half-maximally effective concentration of EGF for inhibition of histamine-stimulated cyclic AMP was 3.9 nM. The equivalent measurement for the inhibition of histamine-stimulated aminopyrine accumulation was 3.0 nM. Aminopyrine accumulation was measure...

  1. Molecular mechanisms underlying mancozeb-induced inhibition of TNF-alpha production

    International Nuclear Information System (INIS)

    Corsini, Emanuela; Viviani, Barbara; Birindelli, Sarah; Gilardi, Federica; Torri, Anna; Codeca, Ilaria; Lucchi, Laura; Bartesaghi, Stefano; Galli, Corrado L.; Marinovich, Marina; Colosio, Claudio

    2006-01-01

    Mancozeb, a polymeric complex of manganese ethylenebisdithiocarbamate with zinc salt, is widely used in agriculture as fungicide. Literature data indicate that ethylenebisdithiocarbamates (EBDTCs) may have immunomodulatory effects in humans. We have recently found in agricultural workers occupationally exposed to the fungicide mancozeb a statistically significant decrease in lipopolysaccharide (LPS)-induced tumor necrosis factor-alpha (TNF) production in leukocytes. TNF is an essential proinflammatory cytokine whose production is normally stimulated during an infection. The purpose of this work was to establish an in vitro model reflecting in vivo data and to characterize the molecular mechanism of action of mancozeb. The human promyelocytic cell line THP-1 was used as in vitro model to study the effects of mancozeb and its main metabolite ethylenthiourea (ETU) on LPS-induced TNF release. Mancozeb, but not ETU, at non-cytotoxic concentrations (1-100 μg/ml), induced a dose- and time-dependent inhibition of LPS-induced TNF release, reflecting in vivo data. The modulatory effect observed was not limited to mancozeb but also other EBDTCs, namely zineb and ziram, showed similar inhibitory effects. Mancozeb must be added before or simultaneously to LPS in order to observe the effect, indicating that it acts on early events triggered by LPS. It is known that nuclear factor-κB (NF-κB) tightly regulates TNF transcription. We could demonstrate that mancozeb, modulating LPS-induced reactive oxygen species generation, prevented IκB degradation and NF-κB nuclear translocation, which in turn resulted in decreased TNF production. To further understand the mechanism of the effect of mancozeb on TNF transcription, THP-1 cells were transfected with NF-κB promoter-luciferase construct, and the effect of mancozeb on luciferase activity was measured. Cells transfected with promoter constructs containing κB site showed decreased LPS-induced luciferase activity relative to control

  2. Stabilization of the activated alphaMbeta2 integrin by a small molecule inhibits leukocyte migration and recruitment.

    Science.gov (United States)

    Björklund, Mikael; Aitio, Olli; Stefanidakis, Michael; Suojanen, Juho; Salo, Tuula; Sorsa, Timo; Koivunen, Erkki

    2006-03-07

    Integrins are potential targets for the development of antiinflammatory agents. Here we develop a novel high-throughput assay by allowing a chemical library to compete with phage display peptide binding and identify a novel small-molecule ligand to the leukocyte-specific alpha(M)beta(2) integrin. The identified thioxothiazolidine-containing compound, IMB-10, had an unexpected activity in that it stabilized binding of alpha(M)beta(2) to its endogenous ligands proMMP-9 and fibrinogen. Single amino acid substitutions in the activity-regulating C-terminal helix and the underlying region in the ligand-binding I domain of the integrin suppressed the effect of IMB-10. A computational model indicated that IMB-10 occupies a distinct cavity present only in the activated form of the integrin I domain. IMB-10 inhibited alpha(M)beta(2)-dependent migration in vitro and inflammation-induced neutrophil emigration in vivo. Stabilization of integrin-mediated adhesion by a small molecule is a novel means to inhibit cell migration and may have a utility in treatment of inflammatory diseases involving leukocyte recruitment.

  3. THYMUS PEPTIDES (THYMULIN, THYMOSIN ALPHA 1 AND THYMOSIN BETA 4 INHIBITING EFFECTS ON THE INTRINSIC BLOOD COAGULATION PATHWAY IN RATS

    Directory of Open Access Journals (Sweden)

    Negrin Negrev

    2017-08-01

    Full Text Available Thymus peptides (thymulin, thymosin alpha 1 and thymosin beta 4 inhibiting effects on the intrinsic blood coagulation pathway in rats Background and purpose: Hemostasis is a basic homeostatic mechanism protecting the body from thrombosis or haemorrhage. A number of pathological conditions, including multiple endocrine disorders modulate the balance between pro- and anticoagulation factors and establish conditions of hyper- or hypocoagulability. Endocrine effects of thymus gland on blood coagulation are not completely elucidated, and data existing on the theme are relatively scarce and partially controversial. The present study was designed to investigate thymus peptides (thymulin, thymosin alpha 1 and thymosin beta 4 effects on key intrinsic pathway plasma clotting factors XII, XI, IX, X and activated partial thromboplastin time (aPTT – a principal marker of blood coagulation via intrinsic pathway of hemocoagulation, in rats. Materials and methods: Plasma clotting factor activities and aPTT were studied on 52 male Wistar intact rats after 3 day s.c. application of the thymic peptides envisaged using routine kinetic coagulometry. Results of the study indicate a significant reduction of FXII activity by thymulin and thymosin alpha 1, and FXI and FIX activity by thymulin and thymosin beta 4. Conclusion: Upper results support the conclusion that thymus peptides thymulin, thymosin alpha 1 and thymosin beta 4 application in rats imposes a distinct tendency of hypocoagulability.

  4. In parkinsonian substantia nigra, alpha-synuclein is modified by acrolein, a lipid-peroxidation product, and accumulates in the dopamine neurons with inhibition of proteasome activity.

    Science.gov (United States)

    Shamoto-Nagai, M; Maruyama, W; Hashizume, Y; Yoshida, M; Osawa, T; Riederer, P; Naoi, M

    2007-01-01

    alpha-Synuclein (alphaSYN) plays a central role in the neural degeneration of Parkinson's disease (PD) through its conformational change. In PD, alphaSYN, released from the membrane, accumulates in the cytoplasm and forms Lewy body. However, the mechanism behind the translocation and conformational change of alphaSYN leading to the cell death has not been well elucidated. This paper reports that in the dopamine neurons of the substantia nigra containing neuromelanin from PD patients, alphaSYN was modified with acrolein (ACR), an aldehyde product of lipid peroxidation. Histopathological observation confirmed the co-localization of protein immunoreactive to anti-alphaSYN and ACR antibody. By Western blot analyses of samples precipitated with either anti-alphaSYN or anti-ACR antibody, increase in ACR-modified alphaSYN was confirmed in PD brain. Modification of recombinant alphaSYN by ACR enhanced its oligomerization, and at higher ACR concentrations alphaSYN was fragmented and polymerized forming a smear pattern in SDS-PAGE. ACR reduced 20S proteasome activity through the direct modification of the proteasome proteins and the production of polymerized ACR-modified proteins, which inhibited proteasome activity in vitro. These results suggest that ACR may initiate vicious cycle of modification and aggregation of proteins, including alphaSYN, and impaired proteolysis system, to cause neuronal death in PD.

  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. Alpha-lipoic acid potently inhibits peroxynitrite-mediated DNA strand breakage and hydroxyl radical formation: implications for the neuroprotective effects of alpha-lipoic acid.

    Science.gov (United States)

    Jia, Zhenquan; Zhu, Hong; Vitto, Michael J; Misra, Bhaba R; Li, Yunbo; Misra, Hara P

    2009-03-01

    Alpha-lipoic acid (LA) has recently been reported to afford protection against neurodegenerative disorders in humans and experimental animals. However, the mechanisms underlying LA-mediated neuroprotection remain an enigma. Because peroxynitrite has been extensively implicated in the pathogenesis of various forms of neurodegenerative disorders, this study was undertaken to investigate the effects of LA in peroxynitrite-induced DNA strand breaks, a critical event leading to peroxynitrite-elicited cytotoxicity. Incubation of phi X-174 plasmid DNA with the 3-morpholinosydnonimine (SIN-1), a peroxynitrite generator, led to the formation of both single- and double-stranded DNA breaks in a concentration- and time-dependent fashion. The presence of LA at 100-1,600 microM was found to significantly inhibit SIN-1-induced DNA strand breaks in a concentration-dependent manner. The consumption of oxygen induced by 250 microM SIN-1 was found to be decreased in the presence of high concentrations of LA (400-1,600 microM), indicating that LA at these concentrations may affect the generation of peroxynitrite from auto-oxidation of SIN-1. It is observed that incubation of the plasmid DNA with authentic peroxynitrite resulted in a significant formation of DNA strand breaks, which could also be dramatically inhibited by the presence of LA (100-1,600 microM). EPR spectroscopy in combination with spin-trapping experiments, using 5,5-dimethylpyrroline-N-oxide (DMPO) as spin trap, resulted in the formation of DMPO-hydroxyl radical adduct (DMPO-OH) from authentic peroxynitrite and LA at 50-1,600 microM inhibited the adduct signal. Taken together, these studies demonstrate for the first time that LA can potently inhibit peroxynitrite-mediated DNA strand breakage and hydroxyl radical formation. In view of the critical involvement of peroxynitrite in the pathogenesis of various neurodegenerative diseases, the inhibition of peroxynitrite-mediated DNA damage by LA may be responsible, at least

  7. Association of apoptosis with the inhibition of extracellular signal-regulated protein kinase activity in the tumor necrosis factor alpha-resistant ovarian carcinoma cell line UCI 101.

    Science.gov (United States)

    Yazlovitskaya, E M; Pelling, J C; Persons, D L

    1999-05-01

    Tumor necrosis factor-alpha (TNF alpha) can function as both an autocrine and a paracrine growth factor and may therefore play a role in ovarian tumor progression. TNF alpha initiates multiple cellular responses, many of which are mediated through the mitogen-activated protein kinase pathways, which transduce signals from the TNF alpha receptors through the cytoplasm to the nucleus, resulting in regulation of gene expression. We examined the role of c-jun N-terminal kinase 1 (JNK1) and extracellular signal-regulated protein kinase (ERK) 1 and 2 in the cellular growth response to TNF alpha in the ovarian carcinoma cell line UCI 101. JNK1 activity was increased to a maximum level ninefold above the basal level after 10-20 min of treatment with 10 ng/mL TNF alpha. A maximum threefold induction of ERK1/2 activity was observed after 1 min of treatment. At concentrations up to 100 ng/mL, TNF alpha had neither a stimulatory nor an inhibitory effect on growth of UCI 101 cells. However, inhibition of TNF alpha-induced ERK1/2 activity by the MAP/ERK kinase 1 inhibitor PD 98059 resulted in 60% inhibition of cell growth in TNF alpha-treated UCI 101 cells. This decrease in cell growth was accompanied by apoptosis, as demonstrated by the presence of a 180-bp DNA ladder. Thus, the inhibition of TNF alpha-induced ERK1/2 activity was associated with induction of apoptosis in the TNF alpha-resistant cell line UCI 101. Inhibition of TNF alpha-induced ERK1/2 activity was accompanied by a subsequent transient increase in TNF alpha-induced JNK1 activity. The significance of this increase with respect to apoptosis induction remains to be determined. These findings demonstrated that ERK1/2 activity can modulate cellular sensitivity to TNF alpha and suggested that the balance between the levels of ERK1/2 and JNK1 activation may be critical in the cellular growth response to TNF alpha.

  8. Inhibition of K+ permeability diminishes alpha 2-adrenoceptor mediated effects on norepinephrine release

    International Nuclear Information System (INIS)

    Zimanyi, I.; Folly, G.; Vizi, E.S.

    1988-01-01

    The effect of two different potassium channel blockers, 4-aminopyridine (4-AP) and quinine, on the alpha 2-adrenoceptor mediated modulation of norepinephrine (NE) release was investigated. Pairs of mouse vasa deferentia were loaded with 3 H-norepinephrine ( 3 H-NE), superfused continuously, and stimulated electrically. 4-AP (5.3 x 10(-4) M), and quinine (10(-5) M) enhanced the stimulation-evoked release of tritium significantly. The electrically induced release of radioactivity was reduced by alpha 2-adrenoceptor agonists (1-NE and xylazine) and enhanced by the alpha 2-adrenoceptor antagonist yohimbine. Both effects were affected markedly by 4-AP or quinine: the depressant action of 1-NA and xylazine was partially antagonized and the facilitatory effect of yohimbine was completely abolished during the blockade of the potassium channels. It is suggested that the blockade of the potassium permeability counteracts negative feedback modulation; therefore, it seems likely that the stimulation of alpha 2-adrenoceptors leads to an enhanced potassium permeability and hyperpolarization of varicose axon terminals

  9. New Method of Inhibition of Activity of Tumor Necrosis Factor Alpha In Patients with Psoriasis.

    Science.gov (United States)

    Gerasun, Borys A

    2016-01-01

    A new method of reduction of tumor necrosis factor alpha activity via intradermal immunization with inactivated autoleukocytes (patent UA97493 (2015) [1]) has been presented in the article. New patents from various countries have been analyzed [2-7]. Patients with psoriasis (24) with high level of tumor necrosis factor alpha in their blood (. 30pg/ml) were immunized with autoleukocytes. Leukocytes were isolated by centrifuging plasma, obtained after precipitation of a patient's heparinized peripheral venous blood. Precipitate was suspended in 1.0 - 1.5ml of a patient's blood serum and 0.1ml of blood was injected into the skin of the back. For determination of autoleukocyte immunization efficacy, concentration of tumor necrosis factor alpha in a patient's blood was compared prior to immunization and at different periods after immunization. In 30 days after single immunization, a considerable decrease in cytokine concentration was observed in all patients (100%); it reduced to zero in 16 out of 24 of immunized individuals (66.7%). The degree of reduction and duration of the achieved effect were individual, thus, if necessary the immunization was repeated several times. The procedure was well tolerated, and general condition of patients was improved. The method of reduction of tumor necrosis factor alpha activity is recommended for implementation into clinical practice.

  10. Saw palmetto extracts potently and noncompetitively inhibit human alpha1-adrenoceptors in vitro

    NARCIS (Netherlands)

    Goepel, M.; Hecker, U.; Krege, S.; Rübben, H.; Michel, M. C.

    1999-01-01

    BACKGROUND: We wanted to test whether phytotherapeutic agents used in the treatment of lower urinary tract symptoms have alpha1-adrenoceptor antagonistic properties in vitro. METHODS: Preparations of beta-sitosterol and extracts of stinging nettle, medicinal pumpkin, and saw palmetto were obtained

  11. Alpha-tocopheryl succinate inhibits malignant mesothelioma by disrupting the fibroblast growth factor autocrine loop

    Czech Academy of Sciences Publication Activity Database

    Stapelberg, M.; Gellert, N.; Swettenham, E.; Tomasetti, M.; Witting, P. K.; Procopio, A.; Neužil, Jiří

    2005-01-01

    Roč. 280, č. 27 (2005), s. 25369-25376 ISSN 0021-9258 Institutional research plan: CEZ:AV0Z50520514 Keywords : alpha-tocopheryl succinate * malignant mesothelioma * fibroblast growth factor Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 5.854, year: 2005

  12. Prestimulus alpha and mu activity predicts failure to inhibit motor responses.

    NARCIS (Netherlands)

    Mazaheri, A.; Nieuwenhuis, I.L.C.; Dijk, H.P. van; Jensen, O.

    2009-01-01

    Do certain brain states predispose humans to commit errors in monotonous tasks? We used MEG to investigate how oscillatory brain activity indexes the brain state in subjects performing a Go-noGo task. Elevated occipital alpha and sensorimotor mu activity just prior to the presentation of the stimuli

  13. 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

  14. 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. Copyright © 2016 Elsevier B.V. and ECNP. All rights reserved.

  15. Effect of lipid extracts of Nigella sativa L. seeds on the liver ATP reduction and alpha-glucosidase inhibition.

    Science.gov (United States)

    Sobhi, Widad; Stevigny, Caroline; Duez, Pierre; Calderon, Bedro Buc; Atmani, Djebbar; Benboubetra, Mustapha

    2016-01-01

    Various extracts from the seeds of Nigella sativa have been used in traditional folk medicine to treat inflammation, liver disorders and arthritis. These seeds have been experimentally shown to possess antioxidant and hepatoprotective properties. Beside the hypoglycaemic and hypolipidemic effects, this study was carried out to evaluate, in vitro, toxicological effect of lipid extracts from the Nigella sativa seeds. The tested fractions were: (i) defatted methanolic extract, (ii) total lipid extract obtained by hexane extraction from methanolic extract and (iii) neutral and polar lipid fractions. The fractions were assessed, in vitro, for their inhibitory activity potential on the enzyme alpha-glucosidase as suppressing the enzyme activity is one among the therapeutic approaches to attenuate postprandial hyperglycemia. High inhibition of alpha-glucosidase by the two polar lipid fractions (F6 and F7) was reflected by their IC50 (0.51±0.04mg/ml and 0.55±0.09mg/ml, respectively), compared to acarbose (0.53±0.06mg/ml) and thymoquinone (0.65±0.05mg/ml). The hypoglycaemic effect of the polar lipid fraction of Nigella sativa could be explained by the inhibition of alpha-glucosidase, which is one of early steps of carbohydrate metabolism. Toxicological evaluation was investigated on precision-cut rat liver slices (PCLS). On PCLS, lipid extracts reduced ATP levels by 27 to 35%. Results indicate suggest that Nigella sativa extracts don't show a hepatoprotective effect against acetaminophen, but don't exhibit a major hepatotoxicity when tested alone.

  16. Involvement of the dehydroleucodine alpha-methylene-gamma-lactone function in GVBD inhibition in Bufo arenarum oocytes.

    Science.gov (United States)

    Sánchez Toranzo, G; López, L A; Martínez, J Zapata; Bühler, M C Gramajo; Bühler, M I

    2010-02-01

    Dehydroleucodine (DhL), a sesquiterpenic lactone, was isolated and purified from aerial parts of Artemisia douglasiana Besser, a medicinal herb used in Argentina. DhL is an alpha-methylene butyro-gamma-lactone ring connected to a seven-membered ring fused to an exocyclic alpha,beta-unsaturated cyclopentenone ring. It has been previously shown that DhL selectively induces a dose-dependent transient arrest in G2 of both meristematic cells and vascular smooth muscle cells. Treatment with DhL induces an inhibition of spontaneous and progesterone-induced maturation in a dose-dependent manner in Bufo arenarum fully grown oocytes arrested at G2, at the beginning of meiosis I. However, the nature of the mechanisms involved in the process is still unknown. The aim of this work was to analyse whether DhL's alpha-methylene-gamma-lactone function is responsible for the inhibition effect on meiosis reinitiation of Bufo arenarum oocytes as well as some of the transduction pathways that could be involved in this effect using a derivative of DhL inactivated for alpha-methylenelactone, the 11,13-dihydro-dehydroleucodine (2H-DhL). The use of 2H-DhL in the maturation promoting factor (MPF) amplification experiments by injection of both cytoplasm with active MPF and of germinal vesicle content showed results similar to the ones obtained with DhL, suggesting that the hydrogenated derivative would act in a similar way to DhL. Pretreatment with DhL or 2H-DhL did not affect the percentage of germinal vesicle breakdown (GVBD) induced by H89, a protein kinase A (PKA) inhibitor, which suggests that these lactones would act on another step of the signalling pathway that induces MPF activation. The fact that both DhL and 2H-Dhl inhibit GVBD induced by okadaic acid microinjection suggests that they could act on the activity of the Myt1 kinase. This idea is supported by the experiments of injection of GV contents in which an inhibitory effect of these lactones on GVBD was also observed. Our

  17. Aromatization of androstenedione and 16alpha-hydroxyandrostenedione in human placental microsomes. Kinetic analysis of inhibition by the 19-oxygenated and 3-deoxy analogs.

    Science.gov (United States)

    Numazawa, Mitsuteru; Watari, Yoko; Komatsu, Sachiko; Yamashita, Kouwa; Nagaoka, Masao

    2008-11-01

    Inhibition of aromatase activity in human placental microsomes with androstenedione (AD) (1a) and its 19-oxygenated derivatives 1b and 1c, their 16alpha-hydroxy compounds 2 and 3, and 3-deoxyandrost-4-ene compounds 5 and 6 was studied using [1beta-(3)H]AD as a substrate and compared to that with [1beta-(3)H]16alpha-hydroxyandrostenedione (16-OHAD). AD series of steroids, compounds 1, inhibited competitively [1beta-(3)H]AD aromatization whereas other 16alpha-hydroxy steroids 2, 3, 5, and 6 inhibited AD aromatization in a non-competitive manner. On the other hand, all of 16-OHAD series, compounds 2, blocked the [1beta-(3)H]16-OHAD aromatization in a competitive manner whereas the AD series steroids 1 as well as the 3-deoxy-16alpha-hydroxy-17-one steroids 5 and 3-deoxy-16alpha,17beta-diol steroids 6 inhibited 16-OHAD aromatization non-competitively. 3-carbonyl and 16alpha-hydroxy functions of 16-OHAD play a critical role of selection of the 16-OHAD binding site. The results suggest that the AD derivatives 1 are kinetically aromatized at a different site from the 16-OHAD derivatives 2. Physical and/or chemical environments around the aromatase protein in the microsomal membrane may play a significant role in the expression of the substrate specificity, and the present results do not exclude the idea that the placental microsomes have a single binding site.

  18. Targeted BMI1 inhibition impairs tumor growth in lung adenocarcinomas with low CEBP alpha expression

    Czech Academy of Sciences Publication Activity Database

    Yong, K.J.; Basseres, D.S.; Welner, R.S.; Zhang, W.C.; Yang, H.; Yan, B.; Alberich-Jorda, Meritxell; Zhang, J.; de Figueiredo-Pontes, L.L.; Battelli, C.; Hetherington, C.J.; Ye, M.; Zhang, H.; Maroni, G.; O'Brien, K.; Magli, M.C.; Borczuk, A.C.; Varticovski, L.; Kocher, O.; Zhang, P.; Moon, Y.C.; Sydorenko, N.; Cao, L.; Davis, T.W.; Thakkar, B.M.; Soo, R.A.; Iwama, A.; Lim, B.; Halmos, B.; Neuberg, D.; Tenen, D.G.; Levantini, E.

    2016-01-01

    Roč. 8, č. 350 (2016), č. článku 350ra104. ISSN 1946-6234 R&D Projects: GA MŠk LK21307 Institutional support: RVO:68378050 Keywords : ccaat/enhancer-binding-protein * acute myeloid-leukemia * factor-c/ebp-alpha * posttranscriptional control * adjuvant chemotherapy * cell-proliferation * down-regulation * drug discovery * gene signature * self-renewal Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 16.796, year: 2016

  19. Synergistic inhibition of human cytomegalovirus replication by interferon-alpha/beta and interferon-gamma

    Directory of Open Access Journals (Sweden)

    Morris Cindy A

    2005-02-01

    Full Text Available Abstract Background Recent studies have shown that gamma interferon (IFN-γ synergizes with the innate IFNs (IFN-α and IFN-β to inhibit herpes simplex virus type 1 (HSV-1 replication in vitro. To determine whether this phenomenon is shared by other herpesviruses, we investigated the effects of IFNs on human cytomegalovirus (HCMV replication. Results We have found that as with HSV-1, IFN-γ synergizes with the innate IFNs (IFN-α/β to potently inhibit HCMV replication in vitro. While pre-treatment of human foreskin fibroblasts (HFFs with IFN-α, IFN-β or IFN-γ alone inhibited HCMV plaque formation by ~30 to 40-fold, treatment with IFN-α and IFN-γ or IFN-β and IFN-γ inhibited HCMV plaque formation by 163- and 662-fold, respectively. The generation of isobole plots verified that the observed inhibition of HCMV plaque formation and replication in HFFs by IFN-α/β and IFN-γ was a synergistic interaction. Additionally, real-time PCR analyses of the HCMV immediate early (IE genes (IE1 and IE2 revealed that IE mRNA expression was profoundly decreased in cells stimulated with IFN-α/β and IFN-γ (~5-11-fold as compared to vehicle-treated cells. Furthermore, decreased IE mRNA expression was accompanied by a decrease in IE protein expression, as demonstrated by western blotting and immunofluorescence. Conclusion These findings suggest that IFN-α/β and IFN-γ synergistically inhibit HCMV replication through a mechanism that may involve the regulation of IE gene expression. We hypothesize that IFN-γ produced by activated cells of the adaptive immune response may potentially synergize with endogenous type I IFNs to inhibit HCMV dissemination in vivo.

  20. The histone deacetylase inhibitor, Vorinostat, represses hypoxia inducible factor 1 alpha expression through translational inhibition.

    Directory of Open Access Journals (Sweden)

    Darren M Hutt

    Full Text Available Hypoxia inducible factor 1α (HIF-1α is a master regulator of tumor angiogenesis being one of the major targets for cancer therapy. Previous studies have shown that Histone Deacetylase Inhibitors (HDACi block tumor angiogenesis through the inhibition of HIF-1α expression. As such, Vorinostat (Suberoylanilide Hydroxamic Acid/SAHA and Romidepsin, two HDACis, were recently approved by the Food and Drug Administration (FDA for the treatment of cutaneous T cell lymphoma. Although HDACis have been shown to affect HIF-1α expression by modulating its interactions with the Hsp70/Hsp90 chaperone axis or its acetylation status, the molecular mechanisms by which HDACis inhibit HIF-1α expression need to be further characterized. Here, we report that the FDA-approved HDACi Vorinostat/SAHA inhibits HIF-1α expression in liver cancer-derived cell lines, by a new mechanism independent of p53, prolyl-hydroxylases, autophagy and proteasome degradation. We found that SAHA or silencing of HDAC9 mechanism of action is due to inhibition of HIF-1α translation, which in turn, is mediated by the eukaryotic translation initiation factor--eIF3G. We also highlighted that HIF-1α translation is dramatically inhibited when SAHA is combined with eIF3H silencing. Taken together, we show that HDAC activity regulates HIF-1α translation, with HDACis such as SAHA representing a potential novel approach for the treatment of hepatocellular carcinoma.

  1. Gamma radiation effect to prostaglandin

    International Nuclear Information System (INIS)

    Coelho, Fernando Rodrigues; Lima, Wothan Tavares de; Rogero, Sizue Ota; Lugao, Ademar Benevolo

    2005-01-01

    Prostaglandins and their analogs are of great physiological importance used to prepare drugs by pharmaceutical industry. But the resistance to radiation sterilization process is not too much studied. This work had the objective of study the relaxation activity of irradiated prostaglandin type E1 on the muscle of respiratory tract. 1% HPMC prostaglandin dried dispersion was submitted to radiation from Co-60 gamma source with 10 kGy/h dose rate at 0, 50, 75 e 100 kGy doses. After irradiation degradation measurement was performed by HPLC analysis and the biological activity by in vitro assay of relaxation activity of muscle, in trachea isolated from rats. The results showed in the maximum radiation dose (]100 kGy) about 5% loss of prostaglandin relaxation activity and degradation of about 30% in relation to non irradiated sample. Prostaglandin dispersion in HPMC can be considered steady after irradiation in the dose used for medical products sterilization. (author)

  2. Synergisms in Alpha-glucosidase Inhibition and Antioxidant Activity of Camellia sinensis L. Kuntze and Eugenia uniflora L. Ethanolic Extracts

    Science.gov (United States)

    Vinholes, Juliana; Vizzotto, Márcia

    2017-01-01

    Background: Camellia sinensis, the most consumed and popular beverages worldwide, and Eugenia uniflora, a Brazilian native species, have been already confirmed to have beneficial effects in the treatment of diabetes mellitus. However, their potential acting together against an enzyme linked to this pathology has never been exploited. Objective: The aim of this study was to evaluate the inhibitory properties of individual and combined ethanolic extracts of the leaves of C. sinensis and E. uniflora over alpha-glucosidase, a key digestive enzyme used on the Type 2 diabetes mellitus (T2DM) control. In addition, their inhibitory activity against 2,2-diphenyl-1-picrylhydrazyl radical (DPPH•) and peroxyl radicals was also assayed. Materials and Methods: Enzyme inhibition and antioxidant potential were assessed based on in vitro assays. Total phenolic compounds, carotenoids, and chlorophylls A and B were achieved using spectrophotometric methods. Results: E. uniflora was almost 40 times more active on alpha-glucosidase than C. sinensis and combined extracts showed a significant synergistic effect with an obtained IC50 value almost 5 times lower than the theoretical value. C. sinensis extract was twice more active than E. uniflora concerning DPPH•, in contrast, E. uniflora was almost 10 times more effective than C. sinensis on inhibition of peroxyl radicals with a significant synergistic effect for combined extracts. The extracts activities may be related with their phytochemicals, mainly phenolic compounds, and chlorophylls. Conclusion: Combined C. sinensis and E. uniflora ethanolic extracts showed synergistic effect against alpha-glucosidase and lipid peroxidation. These herbal combinations can be used to control postprandial hyperglycemia and can also provide antioxidant defenses to patients with T2DM. SUMMARY Alfa-glucosidase and antioxidant Interaction between Camellia sinensis L. Kuntze and Eugenia uniflora L. ethanolic extracts was investigated.Extracts showed

  3. Dimerization inhibits the activity of receptor-like protein-tyrosine phosphatase-alpha

    DEFF Research Database (Denmark)

    Jiang, G; den Hertog, J; Su, J

    1999-01-01

    that dimerization can negatively regulate activity, through the interaction of an inhibitory 'wedge' on one monomer with the catalytic cleft of domain 1 in the other monomer. Here we show that dimerization inhibits the activity of a full-length RPTP in vivo. We generated stable disulphide-bonded full...

  4. Alpha-mangostin inhibits both dengue virus production and cytokine/chemokine expression.

    Science.gov (United States)

    Tarasuk, Mayuri; Songprakhon, Pucharee; Chimma, Pattamawan; Sratongno, Panudda; Na-Bangchang, Kesara; Yenchitsomanus, Pa-Thai

    2017-08-15

    Since severe dengue virus (DENV) infection in humans associates with both high viral load and massive cytokine production - referred to as "cytokine storm", an ideal drug for treatment of DENV infection should efficiently inhibit both virus production and cytokine expression. In searching for such an ideal drug, we discovered that α-mangostin (α-MG), a major bioactive compound purified from the pericarp of the mangosteen fruit (Garcinia mangostana Linn), which has been used in traditional medicine for several conditions including trauma, diarrhea, wound infection, pain, fever, and convulsion, inhibits both DENV production in cultured hepatocellular carcinoma HepG2 and Huh-7 cells, and cytokine/chemokine expression in HepG2 cells. α-MG could also efficiently inhibit all four serotypes of DENV. Treatment of DENV-infected cells with α-MG (20μM) significantly reduced the infection rates of four DENV serotypes by 47-55%. α-MG completely inhibited production of DENV-1 and DENV-3, and markedly reduced production of DENV-2 and DENV-4 by 100 folds. Furthermore, it could markedly reduce cytokine (IL-6 and TNF-α) and chemokine (RANTES, MIP-1β, and IP-10) transcription. These actions of α-MG are more potent than those of antiviral agent (ribavirin) and anti-inflammatory drug (dexamethasone). Thus, α-MG is potential to be further developed as therapeutic agent for DENV infection. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Estrogen inhibits RANKL-stimulated osteoclastic differentiation of human monocytes through estrogen and RANKL-regulated interaction of estrogen receptor-{alpha} with BCAR1 and Traf6

    Energy Technology Data Exchange (ETDEWEB)

    Robinson, Lisa J., E-mail: robinsonlj@msx.upmc.edu [Department of Pathology, University of Pittsburgh, Pittsburgh, PA 15261 (United States); Yaroslavskiy, Beatrice B.; Griswold, Reed D.; Zadorozny, Eva V.; Guo, Lida; Tourkova, Irina L. [Department of Pathology, University of Pittsburgh, Pittsburgh, PA 15261 (United States); Blair, Harry C. [Department of Pathology, University of Pittsburgh, Pittsburgh, PA 15261 (United States); Veteran' s Affairs Medical Center, Pittsburgh, PA 15243 (United States)

    2009-04-15

    The effects of estrogen on osteoclast survival and differentiation were studied using CD14-selected mononuclear osteoclast precursors from peripheral blood. Estradiol at {approx} 1 nM reduced RANKL-dependent osteoclast differentiation by 40-50%. Osteoclast differentiation was suppressed 14 days after addition of RANKL even when estradiol was withdrawn after 18 h. In CD14+ cells apoptosis was rare and was not augmented by RANKL or by 17-{beta}-estradiol. Estrogen receptor-{alpha} (ER{alpha}) expression was strongly down-regulated by RANKL, whether or not estradiol was present. Mature human osteoclasts thus cannot respond to estrogen via ER{alpha}. However, ER{alpha} was present in CD14+ osteoclast progenitors, and a scaffolding protein, BCAR1, which binds ER{alpha} in the presence of estrogen, was abundant. Immunoprecipitation showed rapid ({approx} 5 min) estrogen-dependent formation of ER{alpha}-BCAR1 complexes, which were increased by RANKL co-treatment. The RANKL-signaling intermediate Traf6, which regulates NF-{kappa}B activity, precipitated with this complex. Reduction of NF-{kappa}B nuclear localization occurred within 30 min of RANKL stimulation, and estradiol inhibited the phosphorylation of I{kappa}B in response to RANKL. Inhibition by estradiol was abolished by siRNA knockdown of BCAR1. We conclude that estrogen directly, but only partially, curtails human osteoclast formation. This effect requires BCAR1 and involves a non-genomic interaction with ER{alpha}.

  6. 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...

  7. 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 increase prolactin gene expression but potentiates the effects of epidermal growth factor and cAMP on prolactin promoter activity. RPTPalpha was the only protein-tyrosine phosphatase tested that did this. Thus, the effect of RPTPalpha on prolactin-chloramphenicol acetyltransferase (CAT) promoter activity...... is specific by two criteria. A number of potential RPTPalpha targets were ruled out by finding (a) that they are not affected or (b) that they are not on the pathway to insulin-increased prolactin-CAT activity. The negative effect of RPTPalpha on insulin activation of the prolactin promoter is not due...

  8. 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

    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...... 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...

  9. 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.

  10. Bone changes from prostaglandin therapy

    International Nuclear Information System (INIS)

    Poznanski, A.K.; Fernbach, S.K.; Berry, T.E.; Northwestern Univ., Chicago, IL

    1985-01-01

    Prostaglandin E therapy in infants causes periosteal elevation. Although the changes usually take 30-40 days to become visible, we have seen them as early as nine days. In 15 infants who had prostaglandin E therapy for over six days, three developed periosteal elevation. Three other cases are described in greater detail, with long-term follow-up in two in which the bone remodeled to normal. Gallium scan in one showed increased uptake in areas involved. The periosteal cloaking may mimic Caffey disease but the pattern of involvement is different, since the mandible, which is commonly affected in Caffey disease, is rarely involved in prostaglandin E therapy. (orig.)

  11. Antagonizing the alpha(4)beta(1) Integrin, but Not alpha(4)beta(7), Inhibits Leukocytic Infiltration of the Central Nervous System in Rhesus Monkey Experimental Autoimmune Encephalomyelitis

    NARCIS (Netherlands)

    Haanstra, Krista G.; Hofman, Sam O.; Estevao, Dave M. Lopes; Blezer, Erwin L. A.; Bauer, Jan; Yang, Li-Li; Wyant, Tim; Csizmadia, Vilmos; 't Hart, Bert A.; Fedyk, Eric R.

    2013-01-01

    The immune system is characterized by the preferential migration of lymphocytes through specific tissues (i.e., tissue tropism). Tissue tropism is mediated, in part, by the alpha(4) integrins expressed by T lymphocytes. The alpha(4)beta(1) integrin mediates migration of memory T lymphocytes into the

  12. Apigenin alleviates the symptoms of Staphylococcus aureus pneumonia by inhibiting the production of alpha-hemolysin.

    Science.gov (United States)

    Dong, Jing; Qiu, Jiazhang; Wang, Jianfeng; Li, Hongen; Dai, Xiaohan; Zhang, Yu; Wang, Xin; Tan, Wei; Niu, Xiaodi; Deng, Xuming; Zhao, Shuhua

    2013-01-01

    Staphylococcus aureus is a common human pathogenic bacteria that can cause serious infections, including lethal staphylococcal pneumonia. The development of antimicrobial resistance has limited treatment options for this pathogen; consequently, novel antibiotics and strategies are urgently desired to combat these infections. In recent years, virulence factors secreted by pathogenic microorganisms have been developed as targets for drug discovery. Alpha-hemolysin, a pore-forming cytotoxin that is secreted by most S. aureus strains, is essential for the pathogenesis of S. aureus pneumonia. In this study, we report that apigenin, a compound extracted from parsley that has no antimicrobial activity vs. S. aureus in vitro, can remarkably decrease the production of α-hemolysin at low concentrations. When added to the A549 cells and S. aureus co-culture system, apigenin protected A549 cells from α-hemolysin-mediated injury. Furthermore, in vivo tests indicated that apigenin alleviated injury of the lung tissue and decreased cytokine levels in the bronchoalveolar lavage fluid in the mouse model of S. aureus pneumonia. © 2012 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

  13. SVIP regulates Z variant alpha-1 antitrypsin retro-translocation by inhibiting ubiquitin ligase gp78.

    Directory of Open Access Journals (Sweden)

    Nazli Khodayari

    Full Text Available Alpha-1 antitrypsin deficiency (AATD is an inherited disorder characterized by early-onset emphysema and liver disease. The most common disease-causing mutation is a single amino acid substitution (Glu/Lys at amino acid 342 of the mature protein, resulting in disruption of the 290-342 salt bridge (an electrophoretic abnormality defining the mutation [Z allele, or ZAAT], protein misfolding, polymerization, and accumulation in the endoplasmic reticulum of hepatocytes and monocytes. The Z allele causes a toxic gain of function, and the E3 ubiquitin ligase gp78 promotes degradation and increased solubility of endogenous ZAAT. We hypothesized that the accumulation of ZAAT is influenced by modulation of gp78 E3 ligase and SVIP (small VCP-interacting protein interaction with p97/VCP in ZAAT-expressing hepatocytes. We showed that the SVIP inhibitory effect on ERAD due to overexpression causes the accumulation of ZAAT in a human Z hepatocyte-like cell line (AT01. Overexpression of gp78, as well as SVIP suppression, induces gp78-VCP/p97 interaction in AT01 cells. This interaction leads to retro-translocation of ZAAT and reduction of the SVIP inhibitory role in ERAD. In this context, overexpression of gp78 or SVIP suppression may eliminate the toxic gain of function associated with polymerization of ZAAT, thus providing a potential new therapeutic approach to the treatment of AATD.

  14. Anti-TNF-alpha antibody attenuates subarachnoid hemorrhage-induced apoptosis in the hypothalamus by inhibiting the activation of Erk

    Directory of Open Access Journals (Sweden)

    Ma L

    2018-02-01

    Full Text Available Ling Ma,1 Yong Jiang,2 Yanan Dong,2 Jun Gao,2 Bin Du,2 Dianwei Liu2 1Department of Clinical Laboratory, The Second Hospital of Shandong University, Jinan, Shandong, People’s Republic of China; 2Department of Neurosurgery, Jinan Central Hospital Affiliated to Shandong University, Jinan, Shandong, People’s Republic of China Background: Subarachnoid hemorrhage (SAH can induce apoptosis in many regions of the brain including the cortex and hippocampus. However, few studies have focused on apoptosis in the hypothalamus after SAH. Although some antiapoptotic strategies have been developed for SAH, such as anti-tumor necrosis factor-alpha (TNF-α antibody, the molecular mechanisms underlying this condition have yet to be elucidated. Therefore, the purpose of this study was to evaluate whether SAH could induce apoptosis in the hypothalamus and identify the potential molecular mechanisms underlying the actions of anti-TNF-α antibody, as a therapeutic regimen, upon apoptosis. Materials and methods: SAH was induced in a rat model. Thirty minutes prior to SAH, anti-TNF-α antibody or U0126, an extracellular signal-regulated kinase (Erk inhibitor, was microinjected into the left lateral cerebral ventricle. In addition, phorbol-12-myristate-13-acetate was injected intraperitoneally immediately after the anti-TNF-α antibody microinjection. Then, real-time polymerase chain reaction, Western blotting and immunohistochemistry were used to detect the expression of caspase-3, bax, bcl-2, phosphorylated Erk (p-Erk and Erk. Finally, anxiety-like behavior was identified by using open field. Results: Levels of caspase-3, bax and bcl-2, all showed a temporary rise after SAH in the hypothalamus, indicating the induction of apoptosis in this brain region. Interestingly, we found that the microinjection of anti-TNF-α antibody could selectively block the elevated levels of bax, suggesting the potential role of anti-TNF-α antibody in the inhibition of SAH

  15. 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. Copyright © 2013 Elsevier B.V. All rights reserved.

  16. 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.

  17. A GPR-protein interaction surface of Gi(alpha): implications for the mechanism of GDP-release inhibition.

    Science.gov (United States)

    Natochin, Michael; Gasimov, Karim G; Artemyev, Nikolai O

    2002-01-08

    Proteins containing G-protein regulatory (GPR) motifs represent a novel family of guanine nucleotide dissociation inhibitors (GDIs) for G(alpha) subunits from the Gi family. They selectively interact with the GDP-bound conformation of Gi(alpha) and transducin-alpha (Gt(alpha)), but not with Gs(alpha). A series of chimeric proteins between Gi(alpha)(1) and Gs(alpha) has been constructed to investigate GPR-contact sites on G(alpha) subunits and the mechanism of GPR-protein GDI activity. Analysis of the interaction of two GPR-proteins-AGS3GPR and Pcp2-with the chimeric G(alpha) subunits demonstrated that the GPR-Gi(alpha)(1) interface involves the Gi(alpha)(1) switch regions and Gi(alpha)(1)-144-151, a site within the helical domain. Residues within Gi(alpha)(1)-144-151 form conformation-sensitive contacts with switch III, and may directly interact with a GPR-protein or form a GPR-binding surface jointly with switch III. The helical domain site is critical to the ability of GPR-proteins to act as GDIs. Our data suggest that a mechanism of the GDI activity of GPR-proteins is different from that of GDIs for monomeric GTPases and from the GDI-like activity of G(betagamma) subunits. The GPR-proteins are likely to block a GDP-escape route on G(alpha) subunits.

  18. Kinetic analysis of reversible inhibition of 16alpha-hydroxyandrostenedione aromatization in human placental microsomes by suicide substrates of androstenedione aromatization.

    Science.gov (United States)

    Numazawa, Mitsuteru; Mutsumi, Ayako; Tachibana, Mii; Yoshimura, Akiko

    2003-06-01

    To gain insight into the catalytic function of aromatase and its substrate specificity, we studied reversible inhibition of 16alpha-hydroxyandrostenedione (16alpha-OHAD) aromatization in human placental microsomes by several suicide substrates of androstenedione (AD) aromatization, including 4-hydroxyAD (1), 6-oxoAD (2) and its 19-hydroxy analogue 3, androst-5-ene-4,7,17-trione (4), and 10beta-acetoxyandrost-5-en-7,17-dione (5) that, in contrast, do not cause a suicide inactivation of 16alpha-OHAD aromatization. All inhibitors examined blocked 16alpha-OHAD aromatization in a competitive manner with apparent K(i) values ranging from 0.50 to 980 nM. The relative K(i) values between inhibitors 1-5 obtained in the 16alpha-OHAD aromatization experiments were markedly different from those obtained in the AD aromatization experiments. The results predict that all inhibitors examined bind to the 16alpha-OHAD binding site in a manner that does not cause suicide inactivation of 16alpha-OHAD aromatization. These findings would be useful for understanding the active (binding) site structure as well as the catalytic function of aromatase.

  19. Alpha mangostin Inhibits Hepatic Stellate Cells Activation Through TGF-β/Smad and Akt Signaling Pathways: An in vitro Study in LX2.

    Science.gov (United States)

    Rahmaniah, Rahmaniah; Yuyuntia, Yuyuntia; Soetikno, Vivian; Arozal, Wawaimuli; Antarianto, Radiana Dhewayani; Louisa, Melva

    2018-03-01

    Alpha mangostin has been reported to have activity for the treatment of liver fibrosis in the rats. However, the mechanisms of action are poorly understood. This study was aimed to investigate the effect of alpha mangostin on hepatic stellate cells (HSC) activation and proliferation through TGF-β/Smad and Akt signaling pathways. Immortalized HSC, LX2 cells, were incubated with TGF-β with or without alpha mangostin (5 or 10 μM). Sorafenib 10 µM was used as positive control. LX2 viability was counted using trypan blue exclusion method. The effect of alpha mangostin on TGF-β concentrations, and the expressions of proliferation and fibrogenic markers were evaluated. Alpha mangostin treatment resulted in a reduced proliferation of HSC, decreased Ki-67 and p-Akt expressions. These findings were followed with decreased concentrations of TGF-β in the medium of cells treated with alpha mangostin, decreased expressions of COL1A1, TIMP1, PAI1, α-SMA, and p-Smad3 as fibrogenic markers. These effects were shown to be dose-dependent. Alpha mangostin inhibits hepatic stellate cells proliferation and activation through TGF-β/Smad and Akt signaling pathways in dose dependent manner. © Georg Thieme Verlag KG Stuttgart · New York.

  20. 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

    Protein tyrosine phosphatases (PTPases) are likely to play important roles in insulin action. We recently demonstrated that the nontransmembrane PTPase PTP1B can act as a negative modulator of insulin-stimulated translocation of GLUT4. We now examine the role of PTP-alpha and PTP-kappa (two...... transmembrane PTPases) in this metabolic action of insulin. Rat adipose cells were transfected with either PTP-alpha or PTP-kappa and effects of these PTPases on the translocation of a cotransfected epitope-tagged GLUT4 were studied. Cells overexpressing wild-type PTP-alpha had significantly lower levels...... of cell surface GLUT4 in response to insulin and a threefold decrease in insulin sensitivity when compared with control cells expressing only tagged GLUT4. Co-overexpression of PTP-alpha and PTP1B did not have additive effects, suggesting that these PTPases share common substrates. Cells overexpressing...

  1. Contractile and relaxant actions of prostaglandins on guinea-pig isolated trachea.

    Science.gov (United States)

    Coleman, R. A.; Kennedy, I.

    1980-01-01

    1 The effects of 12 prostaglandins on guinea-pig isolated trachea have been examined in the presence of indomethacin. Two series of experiments were carried out, the first on preparations without tone ('zero tone'), and the second on preparations with tone induced with acetylcholine ('high tone'). 2 The compounds tested fell into two groups. The first, comprising prostaglandins F1 alpha, F2 alpha, F2 alpha acetal, I2 and Wy 17186, contracted both zero and high tone preparations. The second, comprising prostaglandins A1, A2, B1, B2, E1, E2 and F2 beta, contracted zero, but relaxed high tone preparations. Responses to the second group of compounds are probably the resultant of their contractile and relaxant actions. 3 The order of potency for contracting zero tone preparations was prostaglandin E (PGE) greater than F = 1 = Wy 17186 greater than B greater than A, 2-series compounds being 5 to 18 times more potent than 1-series compounds. 4 The order of potency for relaxing high tone preparations was PGE greater than F beta greater than B greater than A greater than Wy 17186 greater than F alpha = I = 0. There was little difference between the potency of 1- and 2-series compounds. 5 The possible relevance of these results to the interpretation of the effects of prostaglandins on human airways is discussed. PMID:7052343

  2. Beta-adrenergic receptor 1 selective antagonism inhibits norepinephrine-mediated TNF-alpha downregulation in experimental liver cirrhosis.

    Directory of Open Access Journals (Sweden)

    Pedro Zapater

    Full Text Available BACKGROUND: Bacterial translocation is a frequent event in cirrhosis leading to an increased inflammatory response. Splanchnic adrenergic system hyperactivation has been related with increased bacterial translocation. We aim at evaluating the interacting mechanism between hepatic norepinephrine and inflammation during liver damage in the presence of bacterial-DNA. ANIMALS AND METHODS: Forty-six mice were included in a 16-week protocol of CCl(4-induced cirrhosis. Laparotomies were performed at weeks 6, 10, 13 and 16. A second set of forty mice injected with a single intraperitoneal dose of CCl(4 was treated with saline, 6-hydroxidopamine, Nebivolol or Butoxamine. After 5 days, mice received E. coli-DNA intraperitoneally. Laparotomies were performed 24 hours later. Liver bacterial-DNA, norepinephrine, TNF-alpha, IL-6 and beta-adrenergic receptor levels were measured. RESULTS: Bacterial-DNA translocation was more frequent in CCl(4-treated animals compared with controls, and increased as fibrosis progressed. Liver norepinephrine and pro-inflammatory cytokines were significantly higher in mice with vs without bacterial-DNA (319.7 ± 120.6 vs 120.7 ± 68.6 pg/g for norepinephrine, 38.4 ± 6.1 vs 29.7 ± 4.2 pg/g for TNF-alpha, 41.8 ± 7.4 vs 28.7 ± 4.3 pg/g for IL-6. Only beta-adrenergic receptor-1 was significantly increased in treated vs control animals (34.6 ± 7.3 vs 12.5 ± 5.3, p=0.01 and correlated with TNF-alpha, IL-6 and norepinephrine hepatic levels in animals with bacterial-DNA. In the second set of mice, cytokine levels were increased in 6-hydroxidopamine and Nebivolol (beta-adrenergic receptor-1 antagonist treated mice compared with saline. Butoxamine (beta-adrenergic receptor-2 antagonist didn't inhibit liver norepinephrine modulation of pro-inflammatory cytokines. CONCLUSIONS: Beta-adrenergic receptor-1 mediates liver norepinephrine modulation of the pro-inflammatory response in CCl(4-treated mice with bacterial-DNA.

  3. Demonstration of specific E-type prostaglandin receptors using enriched preparations of canine parietal cells and [3H]misoprostol free acid

    International Nuclear Information System (INIS)

    Tsai, B.S.; Kessler, L.K.; Schoenhard, G.; Collins, P.W.; Bauer, R.F.

    1987-01-01

    High-affinity, E-type prostaglandin binding sites in enriched canine parietal cell preparations were identified with [ 3 H] misoprostol free acid, a prostaglandin E1 analogue. Saturable, reversible, and highly stereospecific binding was identified, with approximately 8000 binding sites per cell. Prostaglandin I and F bound weakly, and cimetidine and histamine did not bind. The results indicate that [ 3 H] misoprostol free acid binds to E-type prostaglandin receptors, which suggests that the ulcer-healing inhibition of gastric acid secretion by misoprostol results from its interaction with a specific E-type prostaglandin receptor

  4. Demonstration of specific E-type prostaglandin receptors using enriched preparations of canine parietal cells and (/sup 3/H)misoprostol free acid

    Energy Technology Data Exchange (ETDEWEB)

    Tsai, B.S.; Kessler, L.K.; Schoenhard, G.; Collins, P.W.; Bauer, R.F.

    1987-07-27

    High-affinity, E-type prostaglandin binding sites in enriched canine parietal cell preparations were identified with (/sup 3/H) misoprostol free acid, a prostaglandin E1 analogue. Saturable, reversible, and highly stereospecific binding was identified, with approximately 8000 binding sites per cell. Prostaglandin I and F bound weakly, and cimetidine and histamine did not bind. The results indicate that (/sup 3/H) misoprostol free acid binds to E-type prostaglandin receptors, which suggests that the ulcer-healing inhibition of gastric acid secretion by misoprostol results from its interaction with a specific E-type prostaglandin receptor.

  5. 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. Copyright © 2015 Elsevier B.V. All rights reserved.

  6. Starch digestion in tropical fishes: isolation, structural studies and inhibition kinetics of alpha-amylases from two tilapias Oreochromis niloticus and Sarotherodon melanotheron.

    Science.gov (United States)

    Moreau, Y; Desseaux, V; Koukiekolo, R; Marchis-Mouren, G; Santimone, M

    2001-03-01

    alpha-Amylases from the intestinal cavity of two tilapia species, Oreochromis niloticus (ONI-AMY) and Sarotherodon melanotheron (SME-AMY), were purified using ammonium sulfate precipitation, affinity chromatography and chromatofocusing procedures. The purification was approximately 100-fold. The amylolytic activity, specific activity, product distribution, pH and temperature profile of ONI-AMY and SME-AMY are quite similar. The molecular mass differs slightly: 56600 (ONI-AMY) vs. 55500 (SME-AMY). As shown by isoelectric focusing analysis, both amylases contain two isoforms A and B with distinct pI: 7.2 (A) and 7.8 (B), vs. 8.3 (A) and 8.8 (B), respectively. It was not possible to isolate B, since B converts into A with time. The kinetics of the inhibition of ONI-AMY and SME-AMY activity by alpha-, beta- and gamma-cyclodextrin (alpha-, beta- and gamma-CD) were investigated using amylose as the substrate. Statistical analysis of the kinetic data expressed using a general velocity equation and assuming rapid equilibrium showed that the inhibition is of the mixed noncompetitive type. Similar results were obtained with ONI-AMY and SME-AMY. beta- and gamma-CD are stronger inhibitors than alpha-CD. ONI-AMY and SME-AMY are then closely related and show the general features common to the members of the alpha-amylase class (family 13). They enable ONI and SME tilapias to digest starch in food.

  7. Inhibition of activated protein C by recombinant alpha 1-antitrypsin variants with substitution of arginine or leucine for methionine358

    NARCIS (Netherlands)

    Heeb, M.J.; Bischoff, Rainer; Courtney, M.; Griffin, J.H.

    1990-01-01

    alpha 1-Antitrypsin (alpha 1-AT) was recently identified as a major physiologic plasma inhibitor of activated protein C. The reaction with activated protein C of recombinant alpha 1-AT containing amino acid substitutions at the reactive center was studied. The substitution of Arg358 for Met, as

  8. 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

    International Nuclear Information System (INIS)

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

    1976-01-01

    The relative stability of Prostaglandins (PGs) E1, E2 and F1α 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 PGF1α and PGE1 demonstrated greater stability for PGF1α (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-PGF1α 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

  9. Alcohol extracts of Echinacea inhibit production of nitric oxide and tumor necrosis factor-alpha by macrophages in vitro.

    Science.gov (United States)

    Zhai, Zili; Haney, Devon; Wu, Lankun; Solco, Avery; Murphy, Patricia A; Wurtele, Eve S; Kohut, Marian L; Cunnick, Joan E

    2007-09-01

    It has been suggested that Echinacea has anti-inflammatory activity in vivo. Nitric oxide (NO), tumor necrosis factor-alpha (TNF-α), and interleukin-1beta are important mediators in the inflammatory response. The effect of alcohol extracts of E. angustifolia (EA), E. pallida (EPA) and E. purpurea (EP) on the production of these inflammatory mediators in both LPS-stimulated RAW 264.7 macrophages in vitro and murine peritoneal exudate cells (PECs) in vivo were investigated. As macrophages produce these inflammatory mediators in response to pathogenic infection, parallel cultures of macrophages were studied for phagocytosis and intracellular killing of Salmonella enterica. EPA and EP in vitro inhibited NO production and TNF-α release in a dose-dependent manner. RAW 264.7 cells treated with EA or EP showed decreased killing over 24 h, although EA enhanced bacterial phagocytosis. Upon bacterial infection, RAW 264.7 cells produce high levels of NO; however, an Echinacea-mediated decrease in NO production was observed. Echinacea alcohol extracts administered orally at 130 mg/kg per day for seven days had a weak effect on NO production and phagocytosis by LPS-stimulated PECs. The results indicated that all Echinacea species significantly decreased inflammatory mediators in vitro, however, only EA and EP reduced bacterial killing. Oral administration of Echinacea alcohol extracts did not adversely affect the development and anti-bacterial function of inflammatory PECs in vivo, however, NO production was decreased during bacterial infection of PECs.

  10. The effects of E and A prostaglandins on gastric mucosal blood flow and acid secretion in the rat

    Science.gov (United States)

    Main, I. H. M.; Whittle, B. J. R.

    1973-01-01

    1. The effects of prostaglandins E1, E2, A1 and A2 on gastric acid secretion and mucosal blood flow were studied by means of a [14C]-aniline clearance technique in the anaesthetized rat. 2. During intravenous administration of these prostaglandins, in doses which almost completely inhibited pentagastrin- and histamine-induced acid secretion, a fall in clearance was observed. 3. Clearance per unit acid secretion increased during prostaglandin administration, precluding a primary reduction in mucosal blood flow as the mechanism of the antisecretory action. 4. Prostaglandins increased clearance during basal secretion, indicating a direct vasodilator effect on the gastric mucosa. 5. The possibility that endogenous prostaglandins contribute to functional vasodilatation in the gastric mucosa and that exogenous prostaglandins may be of clinical value in the treatment of peptic ulcer is discussed. PMID:4149696

  11. Importance of TNF-alpha in the course of acute infection with Trypanosoma cruzi: influence of its inhibition by pentoxifylline treatment

    Directory of Open Access Journals (Sweden)

    Sonia G Andrade

    2008-02-01

    Full Text Available Infection of C3H/He mice with the Peruvian strain of Trypanosoma cruzi (Biodeme type I, Z2b, a macrophagotropic strain, determined severe parasitism of macrophages, necrosis of the spleen, and high host mortality. In the present study, pentoxifylline (PTX, an inhibitor of TNF-alpha was investigated on its action upon splenic necrosis, parasitemia and host survival. Immunohistochemical data suggested the importance of this cytokine in parasite destruction and decreasing of parasitemia, although paradoxically contributing to the high mortality of infected mice. Necrotic lesions involving several organs, specially the heart, in acute Chagas disease, are important aggravating factors, increasing cardiac morbidity. Advantage of inhibiting TNF-alpha action was herein investigated. Infected mice were divided into two groups: untreated (n = 24, and PTX treated mice (n = 25. PTX was administered in two daily doses of 30 mg/kg/bw, by intraperitoneal route. Normal controls either treated with PTX or saline were also included. Histopathology of the spleen and in situ immunolabeling of TNF-alpha, using anti-TNF-alpha monoclonal antibody, were performed. Necrotic areas were evaluated by morphometry. Mice treated with PTX showed a significant decrease of necrotic areas and diminution of TNF-alpha expression in spleen tissue, suggesting that PTX treatment could control TNF-alpha effects, and thus be used as an adjuvant in the treatment of acute Chagas' disease.

  12. Activity profiles of prostaglandin 15- and 9-hydroxydehydrogenase and 13-reductase in the developing rat kidney.

    Science.gov (United States)

    Pace-Asciak, C

    1975-04-25

    Three prostaglandin F2alpha-catabolizing enzyme activities have been demonstrated in kidneys from adult rats. Activity of each of the enzymes varied with animal age. Whereas 15-hydroxydehydrogenase and delta13-reductase appeared important to the early developing kidney (prior to 4 weeks of age), 9-hydroxydehydrogenase appeared to be characteristic of the adult kidney. Prostaglandin 15-hydroxydehydrogenase rose sharply after birth to a maximal value at 19 days (59-fold relative to the adult) decreasing to adult values by Day 40. Prostaglandin delta13-reductase followed a similar pattern rising about 20-fold at Day 19. Prostaglandin 9-hydroxydehydrogenase, on the other hand, was undetectable up to Day 19, rising gradually to adult values by Day 50. Prostaglandin biosynthesis in whole kidney and renal papilla at the peak period of 15-hydroxydehydrogenase activity, i.e. 19, 22, and 24 days, did not vary significally from adult values. The dramatic rise in 15-hydroxydehydrogenase activity, reflecting an important requirement for prostaglandin inactivation during the first 3 weeks after birth, appears to correlate well with the increase during this period in the number of glomeruli, cortical tubules, and redistribution of blood flow to the cortex. These results suggest for the first time an important relationship between prostaglandin catabolizing activites and nephrogenesis.

  13. Epigallocatechin-3-gallate inhibits secretion of TNF-alpha, IL-6 and IL-8 through the attenuation of ERK and NF-kappaB in HMC-1 cells.

    Science.gov (United States)

    Shin, Hye-Young; Kim, Sang-Hyun; Jeong, Hyun-Ja; Kim, Sang-Yong; Shin, Tae-Yong; Um, Jae-Young; Hong, Seung-Heon; Kim, Hyung-Min

    2007-01-01

    Epigallocatechin-3-gallate (EGCG) is a major form of tea catechin and has a variety of biological activities. In the present study, we investigated the effect of EGCG on the secretion of TNF-alpha, IL-6 and IL-8, as well as its possible mechanism of action by using the human mast cell line (HMC-1). EGCG was treated before the activation of HMC-1 cells with phorbol 12-myristate 13-acetate (PMA) plus calcium ionophore (A23187). To investigate the effect of EGCG on PMA+A23187-stimulated HMC-1 cells, ELISA, Western blot analysis, electrophorectic mobility shift assay and luciferase assay were used in this study. EGCG (100 microM) inhibited PMA+A23187-induced TNF-alpha, IL-6 and IL-8 expression and production. EGCG inhibited the intracellular Ca(2+) level. EGCG attenuated PMA+A23187-induced NF-kappaB and extracellular signal-regulated kinase (ERK1/2) activation, but not that of c-Jun N-terminal kinase or p38 mitogen-activated protein kinase. EGCG inhibited the production of TNF-alpha, IL-6 and IL-8 through the inhibition of the intracellular Ca(2+) level, and of ERK1/2 and NF-kappaB activation. These results indicate that EGCG may be helpful in regulating mast-cell-mediated allergic inflammatory response.

  14. Inhibition of the synthesis of polyamines and DNA in activated lymphocytes by a combination of alpha-methylornithine and methylglyoxal bis(guanylhydrazone).

    Science.gov (United States)

    Morris, D R; Jorstad, C M; Seyfried, C E

    1977-09-01

    The cancer chemotherapeutic drug, methylglyoxal bis(guanylhydrazone), inhibits the synthesis of spermidine and spermine, but allows continued putrescine production in small lymphocytes stimulated by concanavalin A. DNA replication in these cells is inhibited 50% while the synthesis of protein and RNA continues normally. When excess putrescine accumulation in the presence of methylglyoxal bis(guanylhydrazone) was inhibited with alpha-methylornithine, a competitive inhibitor of ornithine decarboxylase, the inhibition of DNA replication was accentuated, with still no effect on protein or RNA synthesis. No inhibition of DNA synthesis by the combination of alpha-methylornithine and methylglyoxal bis(guanylhydrazone) was observed when the inhibitors were added after accumulation of cellular polyamines. In addition, inhibition was reversed by exogenous putrescine, spermidine, or spermine. We conclude that putrescine can fulfill in part the role normally played by spermidine and spermine in DNA replication, and that blocking putrescine synthesis in the presence of methylglyoxal bis(guanylhydrazone) amplifies the polyamine requirement. The implications of this with regard to polyamine synthesis as a site of chemotherapy are discussed.

  15. VP24-Karyopherin Alpha Binding Affinities Differ between Ebolavirus Species, Influencing Interferon Inhibition and VP24 Stability

    Energy Technology Data Exchange (ETDEWEB)

    Schwarz, Toni M.; Edwards, Megan R.; Diederichs, Audrey; Alinger, Joshua B.; Leung, Daisy W.; Amarasinghe, Gaya K.; Basler, Christopher F.; Lyles, Douglas S.

    2016-12-14

    ABSTRACT

    Zaire ebolavirus(EBOV),Bundibugyo ebolavirus(BDBV), andReston ebolavirus(RESTV) belong to the same genus but exhibit different virulence properties. VP24 protein, a structural protein present in all family members, blocks interferon (IFN) signaling and likely contributes to virulence. Inhibition of IFN signaling by EBOV VP24 (eVP24) involves its interaction with the NPI-1 subfamily of karyopherin alpha (KPNA) nuclear transporters. Here, we evaluated eVP24, BDBV VP24 (bVP24), and RESTV VP24 (rVP24) interactions with three NPI-1 subfamily KPNAs (KPNA1, KPNA5, and KPNA6). Using purified proteins, we demonstrated that each VP24 binds to each of the three NPI-1 KPNAs. bVP24, however, exhibited approximately 10-fold-lower KPNA binding affinity than either eVP24 or rVP24. Cell-based assays also indicate that bVP24 exhibits decreased KPNA interaction, decreased suppression of IFN induced gene expression, and a decreased half-life in transfected cells compared to eVP24 or rVP24. Amino acid sequence alignments between bVP24 and eVP24 also identified residues within and surrounding the previously defined eVP24-KPNA5 binding interface that decrease eVP24-KPNA affinity or bVP24-KPNA affinity. VP24 mutations that lead to reduced KPNA binding affinity also decrease IFN inhibition and shorten VP24 half-lives. These data identify novel functional differences in VP24-KPNA interaction and reveal a novel impact of the VP24-KPNA interaction on VP24 stability.

    IMPORTANCEThe interaction of Ebola virus (EBOV) VP24 protein with host karyopherin alpha (KPNA) proteins blocks type I interferon (IFN) signaling, which is a central component of the host innate immune response to viral infection. Here, we quantitatively compared the

  16. 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...

  17. Interactions of a new alpha-aminophosphinic derivative inside the active site of TLN (thermolysin): a model for zinc-metalloendopeptidase inhibition.

    Science.gov (United States)

    Selkti, Mohamed; Tomas, Alain; Gaucher, Jean-François; Prangé, Thierry; Fournié-Zaluski, Marie-Claude; Chen, Huixiong; Roques, Bernard-Pierre

    2003-07-01

    A new alpha-aminophosphinic compound able to inhibit both zinc-containing exopeptidases and endopeptidases has been crystallized with TLN as a model in order to investigate the mode of zinc recognition by the phosphinic moiety and to evaluate the potential role of the free alpha-amino group in the formation of enzyme-inhibitor complexes. In addition to the main interactions between the backbone of the inhibitor and the enzyme active site, it is observed that the phosphinic group acts as a distorted bidentate ligand for the zinc ion, while the free alpha-amino function does not directly participate in interactions within the active site. Association of the present data and the K(i) values of various analogues of the inhibitor towards TLN and neprilysin suggests differences in the hydrophobicity of the S(1)-S(2) domains of the enzymes. This could be taken into account in the design of selective inhibitors.

  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. NCX 4040, a nitric oxide-donating aspirin, exerts anti-inflammatory effects through inhibition of I kappa B-alpha degradation in human monocytes.

    Science.gov (United States)

    Ricciotti, Emanuela; Dovizio, Melania; Di Francesco, Luigia; Anzellotti, Paola; Salvatore, Tania; Di Francesco, Andrea; Sciulli, Maria G; Pistritto, Giuseppa; Monopoli, Angela; Patrignani, Paola

    2010-02-15

    NO-donating aspirins consist of aspirin to which a NO-donating group is covalently linked via a spacer molecule. NCX 4040 and NCX 4016 are positional isomers with respect to the -CH(2)ONO(2) group (para and meta, respectively) on the benzene ring of the spacer. Because positional isomerism is critical for antitumor properties of NO-donating aspirins, we aimed to compare their anti-inflammatory effects with those of aspirin in vitro. Thus, we assessed their impacts on cyclooxygenase-2 activity (by measuring PGE(2) levels), protein expression, and cytokine generation(IL-1beta, IL-18, TNF-alpha, and IL-10) in human whole blood and isolated human monocytes stimulated with LPS. Interestingly, we found that micromolar concentrations of NCX 4040, but not NCX 4016 or aspirin, affected cyclooxygenase-2 expression and cytokine generation. We compared the effects of NCX 4040 with those of NCX 4016 or aspirin on IkappaB-alpha stabilization and proteasome activity in the LPS-stimulated human monocytic cell line THP1. Differently from aspirin and NCX 4016, NCX 4040, at a micromolar concentration range, inhibited IkappaB-alpha degradation. In fact, NCX 4040 caused concentration-dependent accumulation of IkappaB-alpha and its phosphorylated form. This effect was not reversed by 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one, an inhibitor of guanylyl cyclase, thus excluding the contribution of NO-dependent cGMP generation. In contrast, IkappaB-alpha accumulation by NCX 4040 may involve an inhibitory effect on proteasome functions. Indeed, NCX 4040 inhibited 20S proteasome activity when incubated with intact cells but not in the presence of cell lysate supernatants, thus suggesting an indirect inhibitory effect. In conclusion, NCX 4040 is an inhibitor of IkappaB-alpha degradation and proteasome function, and it should be taken into consideration for the development of novel anti-inflammatory and chemopreventive agents.

  20. Specific inhibition of hypoxia-inducible factor (HIF)-1 alpha activation and of vascular endothelial growth factor (VEGF) production by flavonoids.

    Science.gov (United States)

    Hasebe, Yuki; Egawa, Kiyoshi; Yamazaki, Yoko; Kunimoto, Setsuko; Hirai, Yasuaki; Ida, Yoshiteru; Nose, Kiyoshi

    2003-10-01

    Screening using a reporter under the control of the hypoxia-response element (HRE) identified several flavonoids and homoisoflavonoids that inhibit the activation of HRE under hypoxic conditions. Among various compounds, isorhamnetin, luteolin, quercetin, and methyl ophiopogonanone B (MOB) were effective at 3 to 9 microg/ml in inhibiting the reporter activity. The expression of vascular endothelial growth factor (VEGF) mRNA during hypoxia was also inhibited by MOB in HepG2 cells, but the effective doses were 10 to 20 microg/ml. MOB caused destabilization of hypoxia-inducible factor (HIF)-1alpha, as revealed by Western blotting, that was dependent on proteasome activity and the tumor suppressor, p53. The tubular formation and migration of human umbilical vein endothelial cells was also inhibited by MOB. MOB is expected to act as an inhibitor of angiogenesis.

  1. Bothrops asper metalloproteinase BaP1 is inhibited by alpha(2)-macroglobulin and mouse serum and does not induce systemic hemorrhage or coagulopathy.

    Science.gov (United States)

    Escalante, Teresa; Rucavado, Alexandra; Kamiguti, Aura S; Theakston, R David G; Gutiérrez, José María

    2004-02-01

    The ability of the P-I metalloproteinase BaP1, isolated from the venom of the snake Bothrops asper, to induce systemic bleeding, thrombocytopenia and defibrinogenation was assessed in an experimental mouse model. Intravenous administration of BaP1 caused neither systemic bleeding nor any evidence of pathology in lungs, kidneys, liver, heart and brain. Moreover, there were no alterations in the whole blood clotting time or in platelet numbers. In addition, BaP1 did not inhibit collagen-induced platelet aggregation in vitro. Proteolytic and hemorrhagic activities of BaP1 were readily inhibited by the plasma proteinase inhibitor, alpha(2)-macroglobulin, and normal mouse serum also inhibited hemorrhage. Such inhibition may explain why BaP1 induces multiple local tissue-damaging effects, but is largely devoid of systemic toxicity.

  2. Uncoupling of stem cell inhibition from monocyte chemoattraction in MIP-1alpha by mutagenesis of the proteoglycan binding site.

    Science.gov (United States)

    Graham, G J; Wilkinson, P C; Nibbs, R J; Lowe, S; Kolset, S O; Parker, A; Freshney, M G; Tsang, M L; Pragnell, I B

    1996-12-02

    We have studied the role of proteoglycans in the function of Macrophage Inflammatory Protein-1 alpha (MIP-1alpha), a member of the proteoglycan binding chemokine family. Sequence and peptide analysis has identified a basic region within MIP-1alpha which appears to be the major determinant of proteoglycan binding and we have now produced a mutant of MIP-1alpha lacking the basic charges on two of the amino acids within this proteoglycan binding site. This mutant (Hep Mut) appears to have lost the ability to bind to proteoglycans. Bioassay of Hep Mut indicates that it has retained stem cell inhibitory properties but has a compromised activity as a monocyte chemoattractant, thus suggesting uncoupling of these two properties of MIP-1alpha. Receptor studies have indicated that the inactivity of Hep Mut on human monocytes correlates with its inability to bind to CCR1, a cloned human MIP-1alpha receptor. In addition, studies using proteoglycan deficient cells transfected with CCR1 have indicated that the proteoglycan binding site in MIP-1alpha is a site that is also involved in the docking of MIP-1alpha to the monocyte receptor. The site for interaction with the stem cell receptor must therefore be distinct, suggesting that MIP-1alpha utilizes different receptors for these two different biological processes.

  3. Pertussis toxin-sensitive G-protein mediates the alpha 2-adrenergic receptor inhibition of melatonin release in photoreceptive chick pineal cell cultures

    International Nuclear Information System (INIS)

    Pratt, B.L.; Takahashi, J.S.

    1988-01-01

    The avian pineal gland is a photoreceptive organ that has been shown to contain postjunctional alpha 2-adrenoceptors that inhibit melatonin synthesis and/or release upon receptor activation. Physiological response and [32P]ADP ribosylation experiments were performed to investigate whether pertussis toxin-sensitive guanine nucleotide-binding proteins (G-proteins) were involved in the transduction of the alpha 2-adrenergic signal. For physiological response studies, the effects of pertussis toxin on melatonin release in dissociated cell cultures exposed to norepinephrine were assessed. Pertussis toxin blocked alpha 2-adrenergic receptor-mediated inhibition in a dose-dependent manner. Pertussis toxin-induced blockade appeared to be noncompetitive. One and 10 ng/ml doses of pertussis toxin partially blocked and a 100 ng/ml dose completely blocked norepinephrine-induced inhibition. Pertussis toxin-catalyzed [32P]ADP ribosylation of G-proteins in chick pineal cell membranes was assessed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and autoradiography. Membranes were prepared from cells that had been pretreated with 0, 1, 10, or 100 ng/ml pertussis toxin. In the absence of pertussis toxin pretreatment, two major proteins of 40K and 41K mol wt (Mr) were labeled by [32P]NAD. Pertussis toxin pretreatment of pineal cells abolished [32P] radiolabeling of the 40K Mr G-protein in a dose-dependent manner. The norepinephrine-induced inhibition of both cAMP efflux and melatonin release, as assessed by RIA of medium samples collected before membrane preparation, was also blocked in a dose-dependent manner by pertussis toxin. Collectively, these results suggest that a pertussis toxin-sensitive 40K Mr G-protein labeled by [32P]NAD may be functionally associated with alpha 2-adrenergic signal transduction in chick pineal cells

  4. Increased glucose metabolism and alpha-glucosidase inhibition in Cordyceps militaris water extract-treated HepG2 cells

    Science.gov (United States)

    Kim, Dae Jung; Kang, Yun Hwan; Kim, Kyoung Kon; Kim, Tae Woo; Park, Jae Bong

    2017-01-01

    BACKGROUND/OBJECTIVES Recent living condition improvements, changes in dietary habits, and reductions in physical activity are contributing to an increase in metabolic syndrome symptoms including diabetes and obesity. Through such societal developments, humankind is continuously exposed to metabolic diseases such as diabetes, and the number of the victims is increasing. This study investigated Cordyceps militaris water extract (CMW)-induced glucose uptake in HepG2 cells and the effect of CMW treatment on glucose metabolism. MATERIALS/METHODS Colorimetric assay kits were used to determine the glucokinase (GK) and pyruvate dehydrogenase (PDH) activities, glucose uptake, and glycogen content. Either RT-PCR or western blot analysis was performed for quantitation of glucose transporter 2 (GLUT2), hepatocyte nuclear factor 1 alpha (HNF-1α), phosphatidylinositol 3-kinase (PI3k), protein kinase B (Akt), phosphorylated AMP-activated protein kinase (pAMPK), phosphoenolpyruvate carboxykinase, GK, PDH, and glycogen synthase kinase 3 beta (GSK-3β) expression levels. The α-glucosidase inhibitory activities of acarbose and CMW were evaluated by absorbance measurement. RESULTS CMW induced glucose uptake in HepG2 cells by increasing GLUT2 through HNF-1α expression stimulation. Glucose in the cells increased the CMW-induced phosphorylation of AMPK. In turn, glycolysis was stimulated, and glyconeogenesis was inhibited. Furthermore, by studying the mechanism of action of PI3k, Akt, and GSK-3β, and measuring glycogen content, the study confirmed that the glucose was stored in the liver as glycogen. Finally, CMW resulted in a higher level of α-glucosidase inhibitory activity than that from acarbose. CONCLUSION CMW induced the uptake of glucose into HepG2 cells, as well, it induced metabolism of the absorbed glucose. It is concluded that CMW is a candidate or potential use in diabetes prevention and treatment. PMID:28584574

  5. Radioprotection: the non-steroidal anti-inflammatory drugs (NSAIDs) and prostaglandins.

    Science.gov (United States)

    Lee, Tat Khuen; Stupans, Ieva

    2002-11-01

    a variety of effects on cell growth and differentiation. PGE(2) mediates angiogenesis, increasing the supply of oxygen and nutrients, essential for cellular survival and growth. Accordingly, PGE(2) at sufficiently high plasma concentrations enhances cellular survival by inhibiting pro-inflammatory cytokines such as TNF-alpha and IL-1beta. Thus, PGE(2) acts as a modulator, rather than a mediator, of inflammation. Prospective studies have suggested the potential use of misoprostol, a PGE(1) analogue, before irradiation, in prevention of radiation-induced side effects. The current understanding of the pharmacology of NSAIDs and prostaglandins shows great potential to minimise the adverse effects of radiotherapy on normal tissue.

  6. 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.…

  7. 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

  8. Effect of interferon-tau on prostaglandin biosynthesis, transport, and signaling at the time of maternal recognition of pregnancy in cattle: evidence of polycrine actions of prostaglandin E2.

    Science.gov (United States)

    Arosh, J A; Banu, S K; Kimmins, S; Chapdelaine, P; Maclaren, L A; Fortier, M A

    2004-11-01

    Recognition and establishment of pregnancy involve several molecular and cellular interactions among the conceptus, uterus, and corpus luteum (CL). In ruminants, interferon-tau (IFNtau) of embryonic origin is recognized as the pregnancy recognition signal. Endometrial prostaglandin F(2alpha) (PGF(2alpha)) is the luteolysin, whereas PGE(2) is considered a luteoprotective or luteotrophic mediator at the time of establishment of pregnancy. The interplay between IFNtau and endometrial PGs production, transport, and signaling at the time of maternal recognition of pregnancy (MRP) is not well understood. We have studied the expression of enzymes involved in metabolism of PGE(2) and PGF(2alpha), cyclooxygenase-1 (COX-1) and COX-2, PG synthases (PGES and PGFS), PG 15-dehydrogenase, and PG transporter as well as PGE(2) (EP2 and EP3) and PGF(2alpha) receptors. IFNtau influences cell-specific expression of COX-2, PGFS, EP2, and EP3 in endometrium, myometrium, and CL in a spatio-temporal and tissue-specific manner, whereas it does not alter COX-1, PGES, PG 15-dehydrogenase, PG transporter, or PGF(2alpha) receptor expression in any of these tissues. In endometrium, IFNtau decreases PGFS in epithelial cells and increases EP2 in stroma. In myometrium, IFNtau decreases PGFS and increases EP2 in smooth muscle cells. In CL, IFNtau increases PGES and decreases EP3. Together, our results show that IFNtau directly or indirectly increases PGE(2) biosynthesis and EP2-associated signaling in endometrium, myometrium, and CL during MRP. Thus, PGE(2) may play pivotal roles in endometrial receptivity, myometrial quiescence, and luteal maintenance, indicating polycrine (endocrine, exocrine, paracrine, and autocrine) actions of PGE(2) at the time of MRP. Therefore, the establishment of pregnancy may depend not only on inhibition of endometrial PGF(2alpha), but also on increased PGE(2) production in cattle.

  9. Effect of diftalone and other nonsteroidal anti-inflammatory agents on synthesis of prostaglandins (38560).

    Science.gov (United States)

    Carminati, P; Lerner, L J

    1975-02-01

    Diftalone and its metabolites 7, 14-Dihydroxyphthalzino (2,3-b)phthalazine-5, 12 (7H, 14H)-dione, 7-Hydroxyphthalazino (2, 3-b)phthalzine-5,12 (7H, 14H)=DIONE, AND 12 (1(2H)-oxo-2-phthalazinyl)methylbenzoic acid inhibited prostaglandin synthesis in bovine seminal vesicle microsome preparations. Diftalone was the most active of these compounds but less active than indomethacin although more active than phenylbutazone or asprin. The magnitude of the concentration of arachidonic acid influenced the velocity of the reaction in the synthesis of prostaglandins; the highest concentrations inhibited the rate of reaction. The results of the in vitro inhibition of prostaglandin synthetase studies correlated well with those obtained in the in vivo carrageenan edema inhibition studies in the rat. The relative potencies for Diftalone, indomethacin and phenylbutazone were similar with both experimental procedures.

  10. Prostaglandin H synthase catalyzes regiospecific release of tritium from labeled estradiol

    Energy Technology Data Exchange (ETDEWEB)

    Degen, G.H.; Jellinck, P.H.; Hershcopf, R.J.

    1987-06-01

    Prostaglandin H synthase (PHS) from ram seminal vesicle microsomes was found to catalyze the release of tritium (3H) from estradiol (E2) regiospecifically labeled in position C-2 or C-4 of ring A but not from positions C-17 alpha, C-16 alpha, or C-6,7. Formation of 3H2O from ring A of E2 is dependent upon native enzyme supplemented with either arachidonic acid, eicosapentaenoic acid, or hydrogen peroxide and proceeds very rapidly as do other cooxidation reactions catalyzed by PHS-peroxidase. The 3H-loss from ring A of E2 reflecting oxidative displacement of this isotope by PHS increases linearly up to 100 microM under our conditions (8-45 nmol/mg x 5 min). Loss of tritium in various blanks is negligible by comparison. Indomethacin (0.07 and 0.2 mM) inhibited the PHS-dependent release of 3H2O from estradiol but less efficiently than it inhibited DES-cooxidation measured in parallel incubations under similar conditions. Addition of EDTA (0.5 mM) had no effect on the regiospecific transfer of 3H from E2 or on DES-oxidation; ascorbic acid (0.5 mM) or NADH (0.33 mM) clearly inhibited both reactions and to a similar extent. These data suggest that estradiol-2/4-hydroxylation can be catalyzed by PHS in vitro probably via its peroxidase activity and point to PHS as an enzyme that could contribute to catechol estrogen formation in vitro by tissue preparations in the presence of unsaturated fatty acids or peroxides.

  11. Evidence for the inhibition of the terminal step of ruminal alpha-linolenic acid biohydrogenation by condensed tannins.

    Science.gov (United States)

    Khiaosa-Ard, R; Bryner, S F; Scheeder, M R L; Wettstein, H-R; Leiber, F; Kreuzer, M; Soliva, C R

    2009-01-01

    Effects of condensed tannins (CT), either via extract or plant-bound, and saponin extract on ruminal biohydrogenation of alpha-linolenic acid (ALA) were investigated in vitro. Grass-clover hay served as basal diet (control). The control hay was supplemented with extracts contributing either CT from Acacia mearnsii [7.9% of dietary dry matter (DM)] or saponins from Yucca schidigera (1.1% of DM). The fourth treatment consisted of dried sainfoin (Onobrychis viciifolia), a CT-containing forage legume, in an amount also providing 7.9% CT in dietary DM. All diets were supplemented with linseed oil at a level contributing 60% of total dietary ALA in all treatments. Diets were incubated for 10 d (n = 4) in the rumen simulation technique system, using the last 5 d for statistical evaluation. Fatty acids were analyzed in feed, feed residues, incubation fluid, and its effluent. Data were subjected to ANOVA considering diet and experimental run as main effects. Both CT treatments reduced ruminal fiber and crude protein degradation, and lowered incubation fluid ammonia concentration. Only the CT extract suppressed methane formation and shifted microbial populations toward bacteria at cost of protozoa. The saponin extract remained without clear effects on fermentation characteristics except for increased protozoal counts. The extent of ALA biohydrogenation was 20% less with the CT plant, but this probably resulted from reduced organic matter degradability rather than from an inhibition of biohydrogenation. After incubation analysis of incubation fluid effluent and feed residues showed a considerable proportion of the 3 biohydrogenation intermediates, cis-9, trans-11, cis-15 C18:3, trans-11, cis-15 C18:2, and trans-11 C18:1, which did not occur in the initial feeds. Only the CT-extract diet led to a different profile in the effluent compared with the control diet with trans-11 C18:1 being considerably increased at cost of C18:0. This could have been achieved by suppressing

  12. Duodenal prostaglandin synthesis and acid load in health and in duodenal ulcer disease

    International Nuclear Information System (INIS)

    Ahlquist, D.A.; Dozois, R.R.; Zinsmeister, A.R.; Malagelada, J.R.

    1983-01-01

    We sought to test the hypothesis that duodenal ulcer disease results from an imbalance between duodenal acid load, an injurious force, and mucosal prostaglandin generation, a protective factor. Ten patients with duodenal ulcer and 8 healthy controls were studied. The duodenal acid load after an amino acid soup was quantified by a double-marker technique. Mucosal biopsy specimens were taken endoscopically from the duodenal bulb before and after the test meal. Prostaglandin synthesis activity was measured by incubating biopsy homogenates in excess [ 14 C]arachidonic acid. Although mean duodenal acid load was higher in duodenal ulcer, ranges overlapped. Neither the qualitative nor quantitative profile of mucosal prostaglandin synthesis activities differed significantly between test groups. Prostaglandin synthesis activities, however, tended to increase post cibum in controls, but change little or decrease in duodenal ulcer. Only by comparing the responses with a meal of both parameters together (duodenal acid load and the change in prostaglandin synthesis activities) was there complete or nearly complete separation of duodenal ulcer from controls. Greatest discrimination was observed with prostacyclin (6-keto-PGF1 alpha). We conclude that in health, mucosal prostaglandin generation in the duodenum is induced post cibum in relation to duodenal acid load; this may be a physiologic example of adaptive cytoprotection. In duodenal ulcer there may be a defect in such a mechanism

  13. Structure-activity relationship of benzoxazinones and related compounds with respect to the growth inhibition and alpha-amylase activity in cress seedlings.

    Science.gov (United States)

    Kato-Noguchi, Hisashi; Macías, Francisco A; Molinillo, José M G

    2010-10-15

    Benzoxazinones and their degradation compounds inhibited root growth and alpha-amylase activity in cress seedlings. The inhibitory activity of these compounds was divided into three groups: the high active group; 2,4-dihydroxy-7-methoxy-(2H)-1,4-benzoxazin-3(4H)-one, 2,4-dihydroxy-(2H)-1,4-benzoxazin-3(4H)-one, 4-hydroxy-7-methoxy-(2H)-1,4-benzoxazin-3(4H)-one, 4-hydroxy-(2H)-1,4-benzoxazin-3(4H)-one, the moderate active group; 7-methoxy-(2H)-1,4-benzoxazin-3(4H)-one, (2H)-1,4-benzoxazin-3(4H)-one, 6-methoxy-benzoxazolin-2(3H)-one, benzoxazolin-2(3H)-one and 2-amino-phenoxazine-3-one, and the low active group; 2-hydroxy-(2H)-1,4-benzoxazin-3(4H)-one, 2-hydroxy-7-methoxy-(2H)-1,4-benzoxazin-3(4H)-one, 2-amino-7-hydroxyphenoxazine-3-one and 2-amino-7-methoxyphenoxazine-3-one. The structure-activity of these compounds suggests that compounds that have benzoxazinone skeletons are the most active structure, and a hydroxyl group at position C-2 on the benzoxazinone skeleton may not affect inhibitory activity, whereas a hydroxyl group at position N-4 on the skeleton is essential for inhibitory activity. However, the concentration-response curves of these compounds and the I(50) values (the concentrations required for 50% inhibition) for root growth and alpha-amylase indicated that root growth was positively correlated with the alpha-amylase activity in the seedlings. alpha-Amylase is required not only for seed germination, but also subsequent seedling growth until photosynthesis is sufficient to support seedling growth. Therefore, these results suggest that the compounds studied here may inhibit the root growth of cress seedlings by inhibiting alpha-amylase activity. Copyright (c) 2010 Elsevier GmbH. All rights reserved.

  14. Arterial portography using prostaglandin E1

    International Nuclear Information System (INIS)

    Seo, Heung Suk; Kim, Hyung Sik; Lee, Seung Chul; Lee, Seung Ro; Hahm, Chang Kok; Kim, Jung Jin; Cho, Suk Shin

    1987-01-01

    A total of 110 arterial portographies via superior mesenteric artery were performed on 100 patients at Hanyang University Hospital in the past 2 years. There were 20 control portographies and 90 portographies using prostaglandin E 1 Twenty μg prostaglandin E 1 was injected for 30 seconds in the superior mesenteric artery 30 seconds before injection of contrast media. Both control and prostaglandin E 1 portograms were evaluated for quality of opacification and side effects of prostaglandin E 1 were recorded. The results were as follows; 1.The appearance time and optimal opacification time of the portal vein system were obtained approximately 6 seconds earlier in the prostaglandin E 1 portograms than in the control portograms. 2.The incidence of opacification of the intrahepatic portal veins was greater in the prostaglandin E 1 portograms than in the control portograms. 3.The main portal vein and intrahepatic portal veins were more clearly opacified in the prostaglandin... portograms than in the control portograms. 4.The prostaglandin E 1 portograms provided clearer and more detailed opacification of the portal vein system than the control portograms in the same patients. 5.There was a minimal decrease in blood pressure with a concomitant small rise in heart rate and mild abdominal pain following the prostaglandin E 1 injection. The authors found arterial portography using prostaglandin E 1 simple, safe and useful for clear and detailed visualization of the portal vein system

  15. Prostaglandin E2-induced colonic secretion in patients with and without colorectal neoplasia

    DEFF Research Database (Denmark)

    Kaltoft, Nicolai; Tilotta, Maria C; Witte, Anne-Barbara

    2010-01-01

    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......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...

  16. On the mechanism of the involvement of monoamine oxidase in catecholamine-stimulated prostaglandin biosynthesis in particulate fraction of rat brain homogenates: role of hydrogen peroxide.

    Science.gov (United States)

    Seregi, A; Serfözö, P; Mergl, Z; Schaefer, A

    1982-01-01

    The mechanism of involvement of monoamine oxidase (MAO) in catecholamine-stimulated prostaglandin (PG) biosynthesis was studied in the particulate fraction of rat brain homogenates. High concentrations of either noradrenaline (NA) or dopamine (DA) stimulated effectively PGF2 alpha formation. The same amount of 2-phenylethylamine (PEA) acted similarly, provided that it was administered together with a catecholamine analogue or metabolite possessing the 3,4-dihydroxyphenyl nucleus--3,4-dihydroxyphenylalanine (DOPA), 3,4-dihydroxyphenylacetic acid (DOPAC), 3,4-dihydroxyphenylglycol (DOPEG), 3,4-dihydroxyphenylacetaldehyde (DOPAL), or alpha-methylnoradrenaline (alpha-met-NA)--or with SnCl2. In the absence of PEA, these compounds were ineffective with regard to stimulation of PGF2 alpha formation. Catalase, pargyline, or indomethacin abolished completely PGF2 alpha formation elicited either by catecholamines or by PEA plus a 3,4-dihydroxyphenyl compound or SnCl2. With regard to the stimulation of PGF2 alpha formation in the presence of alpha-met-NA, PEA could be replaced by H2O2 generated by the glucose oxidase(GOD)-glucose system. The effect of H2O2 was inhibited by indomethacin or catalase, but pargyline was ineffective. It is assumed that catecholamines play a dual role in the activation of PG biosynthesis in brain tissue. During the enzymatic decomposition of catecholamines MAO produces H2O2, which stimulates endoperoxide synthesis. Simultaneously, catecholamines as hydrogen donors promote the nonenzymatic transformation of endoperoxides into PGF2 alpha. The possible physiological importance of these findings is discussed.

  17. Requirement for protein kinase R in interleukin-1alpha-stimulated effects in cartilage.

    Science.gov (United States)

    Tam, Christine L; Hofbauer, Maria; Towle, Christine A

    2007-12-03

    Interleukin-1 (IL-1) has pleiotropic effects in cartilage. The interferon-induced, double stranded RNA-activated protein kinase PKR that phosphorylates eukaryotic initiation factor 2 (eIF2) alpha has been implicated in cytokine effects in chondrocytes. A compound was recently identified that potently suppresses PKR autophosphorylation (IC50 approximately 200 etaM) and partially restores PKR-inhibited translation in a cell-free system with significant effect in the nanomolar range. The objectives of this study were to exploit this potent PKR inhibitor to assess whether PKR kinase activity is required for catabolic and proinflammatory effects of IL-1alpha in cartilage and to determine whether IL-1alpha causes an increase in eIF2alpha phosphorylation that is antagonized by the PKR inhibitor. Cartilage explants were incubated with the PKR inhibitor and IL-1alpha. Culture media were assessed for sulfated glycosaminoglycan as an indicator of proteoglycan degradation and for prostaglandin E(2). Cartilage extracts were analyzed by Western blot for cyclooxygenase-2 and phosphorylated signaling molecules. Nanomolar concentrations of the PKR inhibitor suppressed proteoglycan degradation and cyclooxygenase-2 accumulation in IL-1alpha-activated cartilage. The PKR inhibitor stimulated or inhibited PGE(2) production with a biphasic dose response relationship. IL-1alpha increased the phosphorylation of both PKR and eIF2alpha, and nanomolar concentrations of PKR inhibitor suppressed the IL-1alpha-induced changes in phosphorylation. The results strongly support PKR involvement in pathways activated by IL-1alpha in chondrocytes.

  18. Effects of nonhypotensive endotoxemia in conscious rats: Role of prostaglandins

    International Nuclear Information System (INIS)

    Burnier, M.; Waeber, B.; Aubert, J.F.; Nussberger, J.; Brunner, H.R.

    1988-01-01

    A nonhypotensive dose of endotoxin was administered to normal conscious rats to evaluate the vascular and humoral effects of endotoxemia per se. Mean blood pressure and heart rate remained stable during the 45 min infusion of Escherichia coli endotoxin. However, a marked increase in plasma renin activity plasma epinephrine and plasma norepinephrine was observed during infusion in endotoxin-treated rats when compared with the vehicle-treated animals. In addition, the blood pressure response to exogenous norepinephrine was significantly reduced during nonhypotensive endotoxemia. Significant changes in regional blood flow distribution, as assessed by radiolabeled microspheres, were observed in endotoxemic rats; in particular a decrease in renal blood flow, and an increase in coronary blood flow were found. The role of prostaglandins in the vascular and humoral alterations induced by nonhypotensive endotoxemia was also examined. Pretreatment with indomethacin (5 mg) prevent the increase in plasma renin activity as well as plasma catecholamine levels. On the contrary, the decreased vascular reactivity and the reduction in renal blood flow observed during endotoxemia were not affected by prostaglandin synthesis inhibition. Thus significant vascular and humoral changes have been found during endotoxemia even in absence of hypotension. The humoral but not the vascular effects of endotoxemia were abolished when prostaglandin synthesis was inhibited

  19. The effects of prostaglandins on guinea-pig isolated intestine and their possible contribution to muscle activity and tone

    Science.gov (United States)

    Bennett, A.; Eley, K.G.; Stockley, Helen L.

    1975-01-01

    1 Prostaglandins F1α and F2α caused contraction of the longitudinal muscle of both guinea-pig isolated ileum and colon, apparently by acting directly on the muscle and on cholinergic nerves. They had little effect on ileal circular muscle. 2 Prostaglandins E1 and E2 caused contraction of the longitudinal muscle of guinea-pig isolated colon, apparently by acting directly on the muscle and on excitatory nerves which are non-cholinergic. Prostaglandin E1 seems more effective than E2 in stimulating these nerves. 3 It seems likely that prostaglandin release in vitro maintains the tone of the longitudinal muscle of guinea-pig colon, whereas release of a prostaglandin E compound inhibits circular muscle tone. PMID:1148509

  20. Effects of prostaglandins E1 and E2 on human, guinea-pig and rat isolated small intestine

    Science.gov (United States)

    Bennett, A.; Eley, K. G.; Scholes, G. B.

    1968-01-01

    1. Prostaglandins E1 and E2 contracted the longitudinal muscle of human, guinea-pig and rat isolated ileum. 2. The site of action varied with the species. In the rat and in some strips of human tissue prostaglandin appeared to have only a direct action on or in the muscle cells. In the other strips of human tissue and in guinea-pig ileum the prostaglandins seemed to stimulate both the intrinsic cholinergic nerves and the muscle cells. 3. In contrast to the longitudinal muscle, the circular muscle of human, guinea-pig and rat isolated ileum was usually inhibited by prostaglandin, apparently by an action directly on the muscle cells. 4. Prostaglandins may play a part in the control of intestinal motility. PMID:5726791

  1. Indirect mesentericoportography with prostaglandin E1

    Energy Technology Data Exchange (ETDEWEB)

    Lammer, J.; Beaufort, F.; Steiner, H.

    1985-08-01

    Indirect mesenteriocoportography was performed in 36 patients after administration of prostaglandin E1 and immediately before contrast medium injection. The results were compared with the findings in a control group of 20 patients receiving tolazolin as vasodilator. On comparing prostaglandin E1 with tolazolin no significant improvement in contrast enhancement of the superior mesentric vein was obtained. On the other hand, prostaglandin E1 seemed to produce less side effects than tolazolin. (Author).

  2. Prostaglandins for preventing postpartum haemorrhage.

    Science.gov (United States)

    Tunçalp, Özge; Hofmeyr, G Justus; Gülmezoglu, A Metin

    2012-08-15

    Prostaglandins have mainly been used for postpartum haemorrhage (PPH) when other measures fail. Misoprostol, a new and inexpensive prostaglandin E1 analogue, has been suggested as an alternative for routine management of the third stage of labour. To assess the effects of prophylactic prostaglandin use in the third stage of labour. We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (7 January 2011). We updated this search on 25 May 2012 and added the results to the awaiting classification section. Randomised trials comparing a prostaglandin agent with another uterotonic or no prophylactic uterotonic (nothing or placebo) as part of management of the third stage of labour. The primary outcomes were blood loss 1000 mL or more and the use of additional uterotonics. Two review authors independently assessed eligibility and trial quality and extracted data. We included 72 trials (52,678 women). Oral or sublingual misoprostol compared with placebo is effective in reducing severe PPH (oral: seven trials, 6225 women, not totalled due to significant heterogeneity; sublingual: risk ratio (RR) 0.66; 95% confidence interval (CI) 0.45 to 0.98; one trial, 661 women) and blood transfusion (oral: RR 0.31; 95% CI 0.10 to 0.94; four trials, 3519 women).Compared with conventional injectable uterotonics, oral misoprostol was associated with higher risk of severe PPH (RR 1.33; 95% CI 1.16 to 1.52; 17 trials, 29,797 women) and use of additional uterotonics, but with a trend to fewer blood transfusions (RR 0.84; 95% CI 0.66 to 1.06; 15 trials; 28,213 women). Additional uterotonic data were not totalled due to heterogeneity. Misoprostol use is associated with significant increases in shivering and a temperature of 38º Celsius compared with both placebo and other uterotonics. Oral or sublingual misoprostol shows promising results when compared with placebo in reducing blood loss after delivery. The margin of benefit may be affected by whether other components of the

  3. The role of prostaglandins in livestock production | Okon | Global ...

    African Journals Online (AJOL)

    ... synthesized) fashion. Prostaglandins are therefore regarded as essential mediators of female reproductive processes, hence, this paper seeks to review the role of Prostaglandins which is exploited in livestock production especially oestrus synchronization and induced parturition. KEYWORDS: Prostaglandins, Production ...

  4. Alpha-Lipoic acid supplementation inhibits oxidative damage, accelerating chronic wound healing in patients undergoing hyperbaric oxygen therapy

    Czech Academy of Sciences Publication Activity Database

    Alleva, R.; Nasole, E.; Di Donato, F.; Borghi, B.; Neužil, Jiří; Tomasetti, M.

    2005-01-01

    Roč. 333, č. 2 (2005), s. 404-410 ISSN 0006-291X Institutional research plan: CEZ:AV0Z50520514 Keywords : alpha-lipoic acid * chronic wound * ROS Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.000, year: 2005

  5. Antidiabetic effects of natural plant extracts via inhibition of carbohydrate hydrolysis enzymes with emphasis on pancreatic alpha amylase.

    Science.gov (United States)

    Etxeberria, Usune; de la Garza, Ana Laura; Campión, Javier; Martínez, J Alfredo; Milagro, Fermín I

    2012-03-01

    The increasing prevalence of type 2 diabetes mellitus and the negative clinical outcomes observed with the commercially available anti-diabetic drugs have led to the investigation of new therapeutic approaches focused on controlling postprandrial glucose levels. The use of carbohydrate digestive enzyme inhibitors from natural resources could be a possible strategy to block dietary carbohydrate absorption with less adverse effects than synthetic drugs. This review covers the latest evidence regarding in vitro and in vivo studies in relation to pancreatic alpha-amylase inhibitors of plant origin, and presents bioactive compounds of phenolic nature that exhibit anti-amylase activity. Pancreatic alpha-amylase inhibitors from traditional plant extracts are a promising tool for diabetes treatment. Many studies have confirmed the alpha-amylase inhibitory activity of plants and their bioactive compounds in vitro, but few studies corroborate these findings in rodents and very few in humans. Thus, despite some encouraging results, more research is required for developing a valuable anti-diabetic therapy using pancreatic alpha-amylase inhibitors of plant origin.

  6. 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

  7. 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

    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.

  8. 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.

  9. New sesquiterpene dimers from Inula britannica inhibit NF-kappaB activation and NO and TNF-alpha production in LPS-stimulated RAW264.7 cells.

    Science.gov (United States)

    Jin, Hui Zi; Lee, Dongho; Lee, Jeong Hyung; Lee, Kyeong; Hong, Young-Soo; Choung, Dong-Ho; Kim, Young Ho; Lee, Jung Joon

    2006-01-01

    A bioassay-guided isolation of an ethyl acetate-soluble extract of the aerial parts of Inula britannica var. chinensis (Rupr.) Regel, using an in vitro NF-kappaB reporter gene assay, led to the isolation of four new sesquiterpene dimers bearing a norbornene moiety, inulanolides A-D, and three known sesquiterpenes, 1,6alpha-dihydroxyeriolanolide, 1-acetoxy-6alpha-hydroxyeriolanolide, and eupatolide. The structures of the new compounds were elucidated by spectroscopic methods. Among these compounds, inulanolides B and D and eupatolide, exhibited potent inhibitory activity on the LPS-induced NF-kappaB activation with IC50 values of 0.49 microM, 0.48 microM, and 1.54 microM, respectively. Consistent with their inhibitory effect on NF-kappaB activation, compounds and also strongly inhibited the production of NO and TNF-alpha in the LPS-stimulated RAW264.7 cells with IC50 values in the range of 2 microM.

  10. Evaluation of a rapid radiometric differentiation test for the Mycobacterium tuberculosis complex by selective inhibition with p-nitro-alpha-acetylamino-beta-hydroxypropiophenone

    International Nuclear Information System (INIS)

    Laszlo, A.; Siddiqi, S.H.

    1984-01-01

    This study is an evaluation of a rapid technique for the differentiation of the Mycobacterium tuberculosis complex from other mycobacteria, using p-nitro-alpha-acetylamino-beta- hydroxypropiophenone (NAP) as a selective inhibitory agent. A total of 416 coded cultures, 234 cultures belonging to the M. tuberculosis complex and 182 cultures belonging to 35 other mycobacterial species, were tested in two laboratories for p-nitro-alpha-acetylamino-beta- hydroxypropiophenone inhibition to concentrations of 5 and 10 micrograms of NAP per ml in Middlebrook 7H12 liquid medium. Two testing modes were compared: the indirect, in which a large bacterial inoculum was used from an isolated culture on a solid medium, and the direct, which used a small inoculum from 7H12 medium. A decrease or no increase in daily 14 CO 2 output as measured by a BACTEC system was considered evidence of inhibition. The data presented show that a concentration of 5 micrograms of NAP per ml can effectively separate the M. tuberculosis complex from other mycobacterial species in 4 to 6 days. The direct test data show that, unlike other conventional biochemical tests, it does not require a heavy inoculum of mycobacteria and can therefore be performed soon after growth is detected by the radiometric method

  11. Alkylation of amide linkages and cleavage of the C chain in the enzyme-activated-substrate inhibition of alpha-chymotrypsin with N-nitrosamides

    International Nuclear Information System (INIS)

    Donadio, S.; Perks, H.M.; Tsuchiya, K.; White, E.H.

    1985-01-01

    Active-site-directed N-nitrosamides inhibit alpha-chymotrypsin through an enzyme-activated-substrate mechanism. In this work, the activation results in the release--in the active site--of benzyl carbonium ions, which alkylate and inhibit the enzyme. The final ratio of benzyl groups to enzyme molecules is 1.0, but the alkyl groups are scattered over a number of sites. Reduction and alkylation of the inhibited enzyme generate peptides insoluble in most media. Guanidine hydrochloride at 6 M proved a good solvent, and its use as an eluant on G-75 Sephadex permitted separation of the peptides. In the case of 14 C-labeled enzyme, such an approach has shown that all of the alkylation occurs on the C chain of the enzyme, the chain of which the active site is constructed. Chemical modification of the peptides with ethylenediamine and N-[3-(dimethylamino)propyl]-N'-ethylcarbodiimide rendered them soluble in dilute acid, permitting high-performance liquid chromatographic separation. Model studies have shown that the benzyl carbonium ions are highly reactive, alkylating amide linkages at both oxygen and nitrogen. Chromatography of this mixture and also 13 C NMR spectroscopy of the intact inhibited enzyme have shown that three major N-alkylations have occurred. Tryptic digestion of the C chain of chymotrypsin, which contains all of the alkylation sites, provides evidence that the stable N sites are principally located between residue 216 and residue 230

  12. 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.

  13. 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

  14. Manipulation of flaxseed inhibits tumor necrosis factor-alpha and interleukin-6 production in ovarian-induced osteoporosis.

    Science.gov (United States)

    Abdelkarem, Hala M; Abd El-Kader, Madeha M; Kasem, Seham A

    2011-04-01

    To evaluate the potential effects of whole flaxseed (FS), and/or flax oil (FO) incorporation into the diet on the level of pro-inflammatory cytokines in ovariectomized (OVX) rats model of osteoporosis. This study was performed in the Food Science & Agriculture Collage, King Saud University, Kingdom of Saudi Arabia from October to December 2009. Forty-eight, 3-month-old female Sprague-Dawley rats were randomly divided into 6 groups: Group 1 - sham + control diet; Group 2 - OVX rats + basal diet; Group 3 - OVX + 20% whole FS; Group 4 - OVX rats + 40% FS; Group 5 - OVX rats + 5% FO; Group 6 - OVX rats + 10% FO. All OVX rats underwent bilateral ovariectomy. The experiment was continued for 2 months. Serum bone alkaline phosphatase (B-ALP), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-alpha), calcium (Ca), phosphorous (P), and magnesium (Mg) were measured. A significant increase of serum IL-6 and TNF-alpha concentrations were observed between OVX rats when compared with Group 1, while there was no significant difference in the activity of B-ALP, serum Ca, P, and Mg among all groups. A remarkable significant decrease of serum levels of IL-6 and TNF-alpha was observed in the group of rats that were fed with FS (Groups 3 and 4) and FO (Groups 5 and 6). This study suggests that FS and FO might be useful in the prevention of estrogen-deficiency induced osteoporosis via decreasing osteoclastogenesis. Further studies are needed to demonstrate their efficacy in humans by using bioactive components of FS, and to clarify their mechanism of action.

  15. Enzymatic synthesis of tritium-labelled prostaglandin D[sub 2] and its conversion to other prostaglandins

    Energy Technology Data Exchange (ETDEWEB)

    Shram, S.I.; Lazurkina, T.Yu.; Shevchenko, V.P.; Nagaev, I.Yu.; Myasoedov, N.F. (AN SSSR, Moscow (Russian Federation). Inst. Molekulyarnoj Genetiki)

    1994-04-01

    The one-stage enzymatic synthesis of tritium-labelled prostaglandin D[sub 2] from labelled arachidonic acid was performed by using the enzyme system PGH-synthetase/PGH-PGD-isomerase. By enzymatic and chemical transformation of [[sup 3]H]PGD[sub 2] the following compounds were obtained: 15-keto-13,14-dihydro-[[sup 3]H]PGD[sub 2], 9[alpha],11[beta]-[[sup 3]H]PGF[sub 2], 9-deoxy-[Delta][sup 9]-[[sup 3]H]-PGD[sub 2] ([[sup 3]H]PGJ[sub 2]) and [Delta][sup 12]-13,14-dihydro-[[sup 3]H]PGJ[sub 2]. It was found that L-selectride is a more effective reducing agent than sodium borohydride in the synthesis of 9[alpha], 11[beta]-[[sup 3]H]PGF[sub 2]. (Author).

  16. 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.

  17. 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. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

  18. 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.

  19. Inhibition of peroxynitrite-mediated cellular toxicity, tyrosine nitration, and alpha1-antiproteinase inactivation by 3-mercapto-2-methylpentan-1-ol, a novel compound isolated from Allium cepa.

    Science.gov (United States)

    Rose, Peter; Widder, Sabine; Looft, Jan; Pickenhagen, Wilhelm; Ong, Choon-Nam; Whiteman, Matthew

    2003-03-07

    Peroxynitrite formation in vivo is implicated in numerous human diseases and there is considerable interest in the use of antioxidants and natural products such as thiols as "peroxynitrite scavengers". We therefore investigated the effects of a recently identified constituent of onions, 3-mercapto-2-methylpentan-1-ol (3-MP), for its ability to inhibit peroxynitrite-mediated processes in vitro and using cultured human cells and compared its effectiveness against glutathione. 3-MP significantly inhibited peroxynitrite-mediated tyrosine nitration and inactivation of alpha(1)-antiproteinase to a greater extent than glutathione at each concentration tested (15-500 microM). 3-MP also inhibited peroxynitrite-induced cytotoxicity, intracellular tyrosine nitration, and intracellular reactive oxygen species generation in human HepG2 cells in culture to a greater extent than glutathione. These data suggest that 3-MP has the potential to act as an inhibitor of ONOO(-)-mediated processes in vivo and that the antioxidant action of 3-MP deserves further study.

  20. 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

  1. 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...

  2. Inhibiting cycloxygenase and ornithine decarboxylase by diclofenac and alpha-difluoromethylornithine blocks cutaneous SCCs by targeting Akt-ERK axis.

    Science.gov (United States)

    Arumugam, Aadithya; Weng, Zhiping; Talwelkar, Sarang S; Chaudhary, Sandeep C; Kopelovich, Levy; Elmets, Craig A; Afaq, Farrukh; Athar, Mohammad

    2013-01-01

    Non-melanoma skin cancer (NMSC) is the most common type of skin cancer in Caucasian populations. Its increasing incidence has been a major public health concern. Elevated expressions of ODC and COX-2 are associated with both murine and human NMSCs. Inhibition of these molecular targets singly employing their respective small molecule inhibitors showed limited success. Here, we show that combined blockade of ODC and COX-2 using their potent inhibitors, DFMO and diclofenac respectively abrogates growth of A431 epidermal xenograft tumors in nu/nu mice by more than 90%. The tumor growth inhibition was associated with a diminution in the proliferation and enhancement in apoptosis. The proliferation markers such as PCNA and cyclin D1 were reduced. TUNEL-positive apoptotic cells and cleaved caspase-3 were increased in the residual tumors. These agents also manifested direct target-unrelated effects. Reduced expression of phosphorylated MAPKAP-2, ERK, and Akt (ser(473) & thr(308)) were noticed. The mechanism by which combined inhibition of ODC/COX attenuated tumor growth and invasion involved reduction in EMT. Akt activation by ODC+COX-2 over-expression was the key player in this regard as Akt inhibition manifested effects similar to those observed by the combined inhibition of ODC+COX-2 whereas forced over-expression of Akt resisted against DFMO+diclofenac treatment. These data suggest that ODC+COX-2 over-expression together leads to pathogenesis of aggressive and invasive cutaneous carcinomas by activating Akt signaling pathway, which through augmenting EMT contributes to tumor invasion.

  3. Inhibiting cycloxygenase and ornithine decarboxylase by diclofenac and alpha-difluoromethylornithine blocks cutaneous SCCs by targeting Akt-ERK axis.

    Directory of Open Access Journals (Sweden)

    Aadithya Arumugam

    Full Text Available Non-melanoma skin cancer (NMSC is the most common type of skin cancer in Caucasian populations. Its increasing incidence has been a major public health concern. Elevated expressions of ODC and COX-2 are associated with both murine and human NMSCs. Inhibition of these molecular targets singly employing their respective small molecule inhibitors showed limited success. Here, we show that combined blockade of ODC and COX-2 using their potent inhibitors, DFMO and diclofenac respectively abrogates growth of A431 epidermal xenograft tumors in nu/nu mice by more than 90%. The tumor growth inhibition was associated with a diminution in the proliferation and enhancement in apoptosis. The proliferation markers such as PCNA and cyclin D1 were reduced. TUNEL-positive apoptotic cells and cleaved caspase-3 were increased in the residual tumors. These agents also manifested direct target-unrelated effects. Reduced expression of phosphorylated MAPKAP-2, ERK, and Akt (ser(473 & thr(308 were noticed. The mechanism by which combined inhibition of ODC/COX attenuated tumor growth and invasion involved reduction in EMT. Akt activation by ODC+COX-2 over-expression was the key player in this regard as Akt inhibition manifested effects similar to those observed by the combined inhibition of ODC+COX-2 whereas forced over-expression of Akt resisted against DFMO+diclofenac treatment. These data suggest that ODC+COX-2 over-expression together leads to pathogenesis of aggressive and invasive cutaneous carcinomas by activating Akt signaling pathway, which through augmenting EMT contributes to tumor invasion.

  4. Gedunin and Azadiradione: Human Pancreatic Alpha-Amylase Inhibiting Limonoids from Neem (Azadirachta indica as Anti-Diabetic Agents.

    Directory of Open Access Journals (Sweden)

    Sudha Ponnusamy

    Full Text Available Human pancreatic α-amylase (HPA inhibitors offer an effective strategy to lower postprandial hyperglycemia via control of starch breakdown. Limonoids from Azadirachta indica known for their therapeutic potential were screened for pancreatic α-amylase inhibition, a known anti-diabetic target. Studies were carried out to reveal their mode of action so as to justify their hypoglycemic potential. Of the nine limonoids isolated/semi-synthesized from A.indica and screened for α-amylase inhibition, azadiradione and exhibited potential inhibition with an IC50 value of 74.17 and 68.38 μM, respectively against HPA under in vitro conditions. Further screening on AR42J α-amylase secretory cell line for cytotoxicity and bioactivity revealed that azadiradione and gedunin exhibited cytotoxicity with IC50 of 11.1 and 13.4μM. Maximal secreted α-amylase inhibition of 41.8% and 53.4% was seen at 3.5 and 3.3μM, respectively. Michaelis-Menten kinetics suggested a mixed mode of inhibition with maltopentaose (Ki 42.2, 18.6 μM and starch (Ki' 75.8, 37.4 μM as substrate with a stiochiometry of 1:1 for both azadiradione and gedunin, respectively. The molecular docking simulation indicated plausible π-alkyl and alkyl-alkyl interactions between the aromatic amino acids and inhibitors. Fluorescence and CD confirmed the involvement of tryptophan and tyrosine in ligand binding to HPA. Thermodynamic parameters suggested that binding is enthalpically and entropically driven with ΔG° of -21.25 kJ mol-1 and -21.16 kJ mol-1 for azadiradione and gedunin, respectively. Thus, the limonoids azadiradione and gedunin could bind and inactivate HPA (anti-diabetic target and may prove to be lead drug candidates to reduce/control post-prandial hyperglycemia.

  5. Inhibition of estrogen receptor β-mediated human telomerase reverse transcriptase gene transcription via the suppression of mitogen-activated protein kinase signaling plays an important role in 15-deoxy-Δ12,14-prostaglandin J2-induced apoptosis in cancer cells

    International Nuclear Information System (INIS)

    Kondoh, Kei; Tsuji, Naoki; Asanuma, Koichi; Kobayashi, Daisuke; Watanabe, Naoki

    2007-01-01

    The nuclear hormone receptor peroxisome proliferator-activated receptor (PPAR)-γ plays a role in cancer development in addition to its role in glucose metabolism. The natural ligand of PPAR-γ, namely, 15-deoxy-Δ 12,14 -prostaglandin J 2 (15d-PGJ 2 ), has been shown to possess antineoplastic activity in cancer cells. However, the mechanism underlying its antineoplastic activity remains to be elucidated. Inhibition of the expression of human telomerase reverse transcriptase (hTERT), a major determinant of telomerase activity, reportedly induces rapid apoptosis in cancer cells. In this study, we investigated the effect of 15d-PGJ 2 on hTERT expression. We found that 15d-PGJ 2 induced apoptosis in the MIAPaCa-2 pancreatic cancer cells and dose-dependently decreased hTERT mRNA and protein expression. Down-regulation of hTERT expression by hTERT-specific small inhibitory RNA also induced apoptosis. Furthermore, 15d-PGJ 2 attenuated the DNA binding of estrogen receptor (ER). MIAPaCa-2 expressed only ERβ, and although its expression did not decrease due to 15d-PGJ 2 , its phosphorylation was suppressed. Additionally, a mitogen-activated protein kinase (MAPK) kinase inhibitor decreased ERβ phosphorylation, and 15d-PGJ 2 attenuated MAPK activity. We conclude that hTERT down-regulation by 15d-PGJ 2 plays an important role in the proapoptotic property of the latter. Furthermore, 15d-PGJ 2 inhibits ERβ-mediated hTERT gene transcription by suppressing ERβ phosphorylation via the inhibition of MAP kinase signaling

  6. Orthosiphol A from the aerial parts of Orthosiphon aristatus is putatively responsible for hypoglycemic effect via alpha-glucosidase inhibition.

    Science.gov (United States)

    Damsud, Thanakorn; Grace, Mary H; Adisakwattana, Sirichai; Phuwapraisirisan, Preecha

    2014-05-01

    An infusion of Orthosiphon aristatus has long been used for diabetes therapy; however, the active principles remained unknown. Herein, we report the identification of the putative agents responsible for this antidiabetic activity using an a-glucosidase-guided isolation. Four flavonoids named sinensetin (1), salvigenin (2), tetramethylscutellarein (3) and 3,7,4'-tri-O-methylkaempferol (4), together with a diterpenoid named orthosiphol A (5), were characterized, based on analysis of their spectroscopic data. Flavonoids 3 and 4 inhibited yeast a-glucosidase with IC,o values of 6.34 and 0.75 mM, respectively, whereas orthosiphol A (5) selectively inhibited intestinal maltase with an IC5o, value of 6.54 mM. A kinetic investigation of 5 indicated that it retarded maltase function in a noncompetitive manner.

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

    OpenAIRE

    Valle, Marta; Ana Elda, Maqueda; Rabella, Mireia; Rodríguez Pujadas, Aina; Antonijoan Arbós, Rosa Maria; Romero Lafuente, Sergio; Alonso López, Joan Francesc; Mañanas Villanueva, Miguel Ángel; Barker, Steven; Friedlander, Pablo; Feilding, Amanda; Riba, Jordi

    2016-01-01

    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 ß-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 experimental...

  8. 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.

  9. 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

  10. Madecassoside inhibits melanin synthesis by blocking ultraviolet-induced inflammation.

    Science.gov (United States)

    Jung, Eunsun; Lee, Jung-A; Shin, Seoungwoo; Roh, Kyung-Baeg; Kim, Jang-Hyun; Park, Deokhoon

    2013-12-16

    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.

  11. 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.

  12. The effects of prostaglandins E1, F1α and F2α on monosynaptic reflexes

    Science.gov (United States)

    Duda, P.; Horton, E. W.; McPherson, Angus

    1968-01-01

    1. Experiments, using electrophysiological recording techniques, were carried out to confirm the report that prostaglandins affect spinal reflexes in cats. 2. Ventral root potentials evoked by stimulation of the ipsilateral dorsal root were recorded. Those with a latent period corresponding to a monosynaptic pathway were used primarily in this investigation. 3. Prostaglandin E1 (3·5-17·8 μg/kg) injected into the aorta reduced the amplitude of monosynaptic responses in six out of ten cats. The effect began about 15 min after injection and lasted over 3 hr. In one cat E1 caused potentiation of the reflex and in three cats there was no effect. 4. Prostaglandin F1α (2·4-3·5 μg/kg) inhibited the monosynaptic response in four cats but in one of these a subsequent large dose (19·6 μg/kg) greatly potentiated the reflex. 5. Prostaglandin F2α (1·4-17·8 μg/kg) injected into the aorta was followed by significant but variable changes in monosynaptic response. In one experiment an intravenous injection (30·3 μg/kg) was followed by a long-lasting potentiation of the reflex response. 6. It is concluded that prostaglandins, two of which have previously been identified in cat brain extracts, have pronounced and long-lasting effects on monosynaptic spinal reflexes. PMID:5659846

  13. 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.

  14. In vitro and in vivo inhibition of alpha-amylases of stored-product mite Acarus siro.

    Science.gov (United States)

    Hubert, Jan; Dolecková-Maresová, Lucie; Hýblová, Jana; Kudlíková, Iva; Stejskal, Václav; Mares, Michael

    2005-01-01

    The stored-product mites are the most abundant and frequent group of pests living on the stored food products in Europe. They endanger public health since they produce allergens and transmit mycotoxin-producing fungi. Novel acaricidal compounds with inhibitory effects on the digestive enzymes of arthropods are a safe alternative to the traditional neurotoxic pesticides used for control of the stored-product pests. In this work, we explored the properties of acarbose, the low molecular weight inhibitor of alpha-amylases (AI), as a novel acaricide candidate for protection of the stored products from infestation by Acarus siro (Acari: Acaridae). In vitro analysis revealed that AI blocked efficiently the enzymatic activity of digestive amylases of A. siro, and decreased the physiological capacity of mite's gut in utilizing a starch component of grain flour. In vivo experiments showed that AI suppressed the population growth of A. siro. The mites were kept for three weeks on experimental diet enriched by AI in concentration range of 0.005 to 0.25%. Population growth of A. siro was negatively correlated with the content of AI in the treated diet with a half-population dose of 0.125%. The suppressive effect of AIs on stored-product mites is discussed in the context of their potential application in GMO crops.

  15. Alpha-L-Fucosidase Serves as a Prognostic Indicator for Intrahepatic Cholangiocarcinoma and Inhibits Its Invasion Capacity

    Directory of Open Access Journals (Sweden)

    Zeyu Shuang

    2018-01-01

    Full Text Available Alpha-L-fucosidase (AFU has been reported to be a predictor of survival in patients with several cancers, but it is unclear whether AFU is associated with prognosis in patients with intrahepatic cholangiocarcinoma (iCCA. In this study, we used receiver operating characteristic (ROC analysis to generate the cutoff point of AFU for overall survival (OS. The prognostic influence of the AFU level in serum on OS was studied using Kaplan-Meier curves. Moreover, invasion assays and Western blotting were performed to explore the effects of AFU on iCCA invasion in vitro. We found that higher AFU levels (≥20.85 U/L were significantly associated with favorable median OS (44.3 months versus 20.1 months; P=0.022 in iCCA patients. Cox regression models’ analyses showed that the AFU level was an independent predictor for OS (P=0.006. Moreover, our results revealed that the AFU could impair the invasion capability of the iCCA cells, HuH28, and also downregulated the expression of matrix metalloproteinase 2 and matrix metalloproteinase 9. In conclusion, our results indicate that AFU is a significantly favorable prognostic factor in iCCA patients.

  16. Alpha cyano-4-hydroxy-3-methoxycinnamic acid inhibits proliferation and induces apoptosis in human breast cancer cells.

    Directory of Open Access Journals (Sweden)

    Lamia Hamdan

    Full Text Available This study investigated the underlying mechanism of 4-hydroxy-3-methoxycinnamic acid (ACCA, on the growth of breast cancer cells and normal immortal epithelial cells, and compared their cytotoxic effects responses. Treatment of breast cancer cells (MCF-7, T47D, and MDA-231 with ACCA resulted in dose- and time-dependent decrease of cell proliferation, viability in colony formation assay, and programmed cell death (apoptosis with minimal effects on non-tumoral cells. The ability of ACCA to suppress growth in cancer cells not expressing or containing defects in p53 gene indicates a lack of involvement of this critical tumor suppressor element in mediating ACCA-induced growth inhibition. Induction of apoptosis correlated with an increase in Bax protein, an established inducer of programmed cell death, and the ratio of Bax to Bcl-2, an established inhibitor of apoptosis. We also documented the ability of ACCA to inhibit the migration and invasion of MDA-231 cells with ACCA in vitro. Additionally, tumor growth of MDA-231 breast cancer cells in vivo was dramatically affected with ACCA. On the basis of its selective anticancer inhibitory activity on tumor cells, ACCA may represent a promising therapeutic drug that should be further evaluated as a chemotherapeutic agent for human breast cancer.

  17. Regulation of Class IA PI 3-kinases: C2 domain-iSH2 domain contacts inhibit p85/p110alpha and are disrupted in oncogenic p85 mutants.

    Science.gov (United States)

    Wu, Haiyan; Shekar, S Chandra; Flinn, Rory J; El-Sibai, Mirvat; Jaiswal, Bijay S; Sen, K Ilker; Janakiraman, Vasantharajan; Seshagiri, Somasekar; Gerfen, Gary J; Girvin, Mark E; Backer, Jonathan M

    2009-12-01

    We previously proposed a model of Class IA PI3K regulation in which p85 inhibition of p110alpha requires (i) an inhibitory contact between the p85 nSH2 domain and the p110alpha helical domain, and (ii) a contact between the p85 nSH2 and iSH2 domains that orients the nSH2 so as to inhibit p110alpha. We proposed that oncogenic truncations of p85 fail to inhibit p110 due to a loss of the iSH2-nSH2 contact. However, we now find that within the context of a minimal regulatory fragment of p85 (the nSH2-iSH2 fragment, termed p85ni), the nSH2 domain rotates much more freely (tau(c) approximately 12.7 ns) than it could if it were interacting rigidly with the iSH2 domain. These data are not compatible with our previous model. We therefore tested an alternative model in which oncogenic p85 truncations destabilize an interface between the p110alpha C2 domain (residue N345) and the p85 iSH2 domain (residues D560 and N564). p85ni-D560K/N564K shows reduced inhibition of p110alpha, similar to the truncated p85ni-572(STOP). Conversely, wild-type p85ni poorly inhibits p110alphaN345K. Strikingly, the p110alphaN345K mutant is inhibited to the same extent by the wild-type or truncated p85ni, suggesting that mutation of p110alpha-N345 is not additive with the p85ni-572(STOP) mutation. Similarly, the D560K/N564K mutation is not additive with the p85ni-572(STOP) mutant for downstream signaling or cellular transformation. Thus, our data suggests that mutations at the C2-iSH2 domain contact and truncations of the iSH2 domain, which are found in human tumors, both act by disrupting the C2-iSH2 domain interface.

  18. 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 of...

  19. Novel anti-ulcer alpha,beta-unsaturated lactones inhibit compound 48/80-induced mast cell degranulation.

    Science.gov (United States)

    Penissi, Alicia B; Vera, Mariano E; Mariani, María L; Rudolph, María I; Ceñal, Juan P; de Rosas, Juan C; Fogal, Teresa H; Tonn, Carlos E; Favier, Laura S; Giordano, Oscar S; Piezzi, Ramón S

    2009-06-10

    The present study was designed to examine the effects of a sesquiterpene lactone isolated from Artemisia douglasiana Besser (dehydroleucodine), a xanthanolide sesquiterpene isolated from Xanthium cavanillesii Schouw (xanthatin) and a semisynthetic butenolide (3-benzyloxymethyl-5H-furan-2-one) on mast cell degranulation induced by compound 48/80. Peritoneal mast cells from male adult Sprague-Dawley rats were purified in Percoll, preincubated in the presence of test lactones (dehydroleucodine, xanthatin or 3-benzyloxymethyl-5H-furan-2-one) and then challenged with the mast cell activator compound 48/80 (10 microg/ml). Concentration-response and kinetic studies of mast cell serotonin release evoked by compound 48/80, evaluation of mast cell viability and morphology by light and electron microscopy, and comparative studies using ketotifen and sodium chromoglycate were carried out. Serotonin release studies, carried out together with morphological studies, showed the effectiveness of the above lactones to stabilize mast cells. The comparative study with ketotifen and sodium chromoglycate, well known mast cell stabilizers, showed the following order of potency dehydroleucodine=xanthatin>3-benzyloxymethyl-5H-furan-2-one> or =ketotifen/sodium chromoglycate to inhibit mast cell serotonin release induced by compound 48/80. The present study provides the first strong evidence in favour of the hypothesis that dehydroleucodine, xanthatin and 3-benzyloxymethyl-5H-furan-2-one inhibit compound 48/80-induced serotonin release from peritoneal mast cells, acting thus as mast cell stabilizers. Our findings may provide an insight into the design of novel pharmacological agents which may be used to regulate the mast cell response.

  20. Biosynthesis of prostaglandins in gingiva of patients with chronic periodontitis

    International Nuclear Information System (INIS)

    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 [ 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

  1. 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.

  2. 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...

  3. Prostaglandin Receptor Signaling in Disease

    Directory of Open Access Journals (Sweden)

    Toshiyuki Matsuoka

    2007-01-01

    Full Text Available Prostanoids, consisting of the prostaglandins (PGs and the thromboxanes (TXs, are a group of lipid mediators formed in response to various stimuli. They include PGD2, PGE2, PGF2α, PGI2, and TXA2. They are released outside of the cells immediately after synthesis, and exert their actions by binding to a G-protein coupled rhodopsin-type receptor on the surface of target cells. There are eight types of the prostanoid receptors conserved in mammals from mouse to human. They are the PGD receptor (DP, four subtypes of the PGE receptor (EP1, EP2, EP3, and EP4, the PGF receptor (FP, PGI receptor (IP, and TXA receptor (TP. Recently, mice deficient in each of these prostanoid receptors were generated and subjected to various experimental models of disease. These studies have revealed the roles of PG receptor signaling in various pathological conditions, and suggest that selective manipulation of the prostanoid receptors may be beneficial in treatment of the pathological conditions. Here we review these recent findings of roles of prostanoid receptor signaling and their therapeutic implications.

  4. Aspirin and PPAR-alpha activators inhibit monocyte chemoattractant protein-1 expression induced by high glucose concentration in human endothelial cells.

    Science.gov (United States)

    Dragomir, Elena; Tircol, Magdalena; Manduteanu, Ileana; Voinea, Manuela; Simionescu, Maya

    2006-06-01

    Activated endothelial cells express monocyte chemoattractant protein-1 (MCP-1), a chemokine which is reportedly involved in the recruitment of plasma monocytes in the early stages of atherosclerosis. Since accelerated atherosclerosis is the main complication of diabetes and both diseases encompass an inflammatory reaction, we hypothesized that the anti-inflammatory drugs, aspirin and peroxisome proliferator-activated receptor (PPAR-alpha) activators (fenofibrate and clofibrate), could have an effect on the high glucose-induced MCP-1 expression in endothelial cells. To test this assumption, as well as the possible mechanisms involved, the MCP-1 expression and secretion, the reactive oxygen species levels, nuclear factor-kB (NF-kB) and activator protein-1 (AP-1) expression were determined in human endothelial cells exposed to high glucose concentrations in the presence of aspirin, fenofibrate and clofibrate. Human endothelial cells kept in normal glucose concentration in the absence of drugs were used as control. The results showed that (i) aspirin, fenofibrate and clofibrate decrease significantly the MCP-1 expression and secretion in human endothelial cells; (ii) the high glucose up-regulated expression of MCP-1 in endothelial cells was significantly reduced by inhibitors of NF-kB and reactive oxygen species; (iii) all drugs notably decrease the level of the reactive oxygen species and activation of NF-kB and AP-1. Together, the findings indicate that in endothelial cells aspirin and PPAR-alpha activators reduce the high glucose-increased expression of MCP-1 by a mechanism that includes the inhibition of reactive oxygen species, and decrease of AP-1 and NF-kB activation.

  5. Inhibition of both COX-1 and COX-2 and resulting decrease in the level of prostaglandins E2 is responsible for non-steroidal anti-inflammatory drug (NSAID)-dependent exacerbation of colitis.

    Science.gov (United States)

    Tanaka, Ken-Ichiro; Suemasu, Shintaro; Ishihara, Tomoaki; Tasaka, Yuichi; Arai, Yasuhiro; Mizushima, Tohru

    2009-01-28

    A number of clinical studies have shown that non-steroidal anti-inflammatory drugs (NSAIDs) exacerbate inflammatory bowel disease; however the molecular mechanism whereby this occurs remains unclear. NSAIDs inhibit cyclooxygenase (COX), which has subtypes COX-1 and COX-2. In this study, we have examined the effect of various types of NSAIDs on the development of dextran sulfate sodium (DSS)-induced colitis, an animal model of inflammatory bowel disease. The DSS-induced colitis was worsened by administration of non-selective NSAIDs but not by COX-1 or COX-2 selective inhibitors. However, administration of a combination of both COX-1- and COX-2-selective inhibitors exacerbated the colitis. The intestinal level of PGE(2) dramatically decreased in response to administration of COX-1- and COX-2-selective inhibitors, and exogenously administered PGE(2) suppressed the exacerbation of colitis by NSAIDs. The expression of mucin proteins, which protect the intestinal mucosa, was suppressed by non-selective NSAIDs and this expression was restored by PGE(2), both in vivo and in vitro. Intestinal mucosal cell growth was inhibited by non-selective NSAIDs and this cell growth was restored by PGE(2), both in vivo and in vitro. This study provides evidence that inhibition of both COX-1 and COX-2 and the resulting dramatic decrease in the intestinal level of PGE(2) is responsible for NSAID-dependent exacerbation of DSS-induced colitis. Furthermore, expression of mucin proteins and intestinal mucosal cell growth seems to be involved in this exacerbation and its suppression by PGE(2).

  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

    SPs) that suppress---- TNF and IL-12 secretion from LPS-activated human dendritic cells (DCs). Analysis by liquid chromatography tandem mass spectrometry identified this compound as prostaglandin (PG)E2. The purified compound showed similar properties compared with TsSPs and commercial PGE2 in modulating LPS....../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. Preventive effect of Dioscorea japonica on squamous cell carcinoma of mouse skin involving down-regulation of prostaglandin E2 synthetic pathway.

    Science.gov (United States)

    Tsukayama, Izumi; Toda, Keisuke; Takeda, Yasunori; Mega, Takuto; Tanaka, Mitsuki; Kawakami, Yuki; Takahashi, Yoshitaka; Kimoto, Masumi; Yamamoto, Kei; Miki, Yoshimi; Murakami, Makoto; Suzuki-Yamamoto, Toshiko

    2018-03-01

    Hyperproduced prostaglandin E 2 by cyclooxygenase-2 and microsomal prostaglandin E synthase-1 evokes several pathophysiological responses such as inflammation and carcinogenesis. Our recent study demonstrated that Dioscorea japonica extract suppressed the expression of cyclooxygenase-2 and microsomal prostaglandin E synthase-1 and induced apoptosis in lung carcinoma A549 cells. In the present study, we investigated the effects of Dioscorea japonica on squamous cell carcinoma of mouse skin. Dioscorea japonica feeding and Dioscorea japonica extract topical application suppressed the expression of cyclooxygenase-2, microsomal prostaglandin E synthase-1, interleukin-1β and interleukin-6 and inhibited tumor formation, hyperplasia and inflammatory cell infiltration. Immunohistochemical analyses showed the immunoreactivities of cyclooxygenase-2 and microsomal prostaglandin E synthase-1 in tumor keratinocytes and stronger immunoreactivities of cyclooxygenase-2 and hematopoietic prostaglandin D synthase in epidermal dendritic cells (Langerhans cells). Treatment with Dioscorea japonica decreased the immunoreactivity of cyclooxygenase-2 and microsomal prostaglandin E synthase-1. These results indicate that Dioscorea japonica may have inhibitory effects on inflammation and carcinogenesis via suppression of the prostaglandin E 2 synthetic pathway.

  8. Preventive effect of Dioscorea japonica on squamous cell carcinoma of mouse skin involving down-regulation of prostaglandin E2 synthetic pathway

    Science.gov (United States)

    Tsukayama, Izumi; Toda, Keisuke; Takeda, Yasunori; Mega, Takuto; Tanaka, Mitsuki; Kawakami, Yuki; Takahashi, Yoshitaka; Kimoto, Masumi; Yamamoto, Kei; Miki, Yoshimi; Murakami, Makoto; Suzuki-Yamamoto, Toshiko

    2018-01-01

    Hyperproduced prostaglandin E2 by cyclooxygenase-2 and microsomal prostaglandin E synthase-1 evokes several pathophysiological responses such as inflammation and carcinogenesis. Our recent study demonstrated that Dioscorea japonica extract suppressed the expression of cyclooxygenase-2 and microsomal prostaglandin E synthase-1 and induced apoptosis in lung carcinoma A549 cells. In the present study, we investigated the effects of Dioscorea japonica on squamous cell carcinoma of mouse skin. Dioscorea japonica feeding and Dioscorea japonica extract topical application suppressed the expression of cyclooxygenase-2, microsomal prostaglandin E synthase-1, interleukin-1β and interleukin-6 and inhibited tumor formation, hyperplasia and inflammatory cell infiltration. Immunohistochemical analyses showed the immunoreactivities of cyclooxygenase-2 and microsomal prostaglandin E synthase-1 in tumor keratinocytes and stronger immunoreactivities of cyclooxygenase-2 and hematopoietic prostaglandin D synthase in epidermal dendritic cells (Langerhans cells). Treatment with Dioscorea japonica decreased the immunoreactivity of cyclooxygenase-2 and microsomal prostaglandin E synthase-1. These results indicate that Dioscorea japonica may have inhibitory effects on inflammation and carcinogenesis via suppression of the prostaglandin E2 synthetic pathway.

  9. 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.

  10. 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.

  11. Vitexin reduces hypoxia-ischemia neonatal brain injury by the inhibition of HIF-1alpha in a rat pup model.

    Science.gov (United States)

    Min, Jia-Wei; Hu, Jiang-Jian; He, Miao; Sanchez, Russell M; Huang, Wen-Xian; Liu, Yu-Qiang; Bsoul, Najeeb Bassam; Han, Song; Yin, Jun; Liu, Wan-Hong; He, Xiao-Hua; Peng, Bi-Wen

    2015-12-01

    Previous studies have demonstrated that the early suppression of HIF-1α after hypoxia-ischemia (HI) injury provides neuroprotection. Vitexin (5, 7, 4-trihydroxyflavone-8-glucoside), an HIF-1α inhibitor, is a c-glycosylated flavone that has been identified in medicinal plants. Therefore, we hypothesized that treatment with vitexin would protect against HI brain injury. Newborn rat pups were subjected to unilateral carotid artery ligation followed by 2.5 h of hypoxia (8% O2 at 37 °C). Vitexin (30, 45 or 60 mg/kg) was administered intraperitoneally at 5 min or 3 h after HI. Vitexin, administered 5 min after HI, was neuroprotective as seen by decreased infarct volume evaluated at 48 h post-HI. This neuroprotection was removed when vitexin was administered 3 h after HI. Neuronal cell death, blood-brain barrier (BBB) integrity, brain edema, HIF-1α and VEGF protein levels were evaluated using a combination of Nissl staining, IgG staining, brain water content, immunohistochemistry and Western blot at 24 and 48 h after HI. The long-term effects of vitexin were evaluated by brain atrophy measurement, Nissl staining and neurobehavioral tests. Vitexin (45 mg/kg) ameliorated brain edema, BBB disruption and neuronal cell death; Upregulation of HIF-1α by dimethyloxalylglycine (DMOG) increased the BBB permeability and brain edema compared to HI alone. Vitexin attenuated the increase in HIF-1α and VEGF. Vitexin also had long-term effects of protecting against the loss of ipsilateral brain and improveing neurobehavioral outcomes. In conclusion, our data indicate early HIF-1α inhibition with vitexin provides both acute and long-term neuroprotection in the developing brain after neonatal HI injury. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. The effect of a metalloproteinase inhibitor (GI5402) on tumor necrosis factor-alpha (TNF-alpha) and TNF-alpha receptors during human endotoxemia

    NARCIS (Netherlands)

    Dekkers, P. E.; Lauw, F. N.; ten Hove, T.; te Velde, A. A.; Lumley, P.; Becherer, D.; van Deventer, S. J.; van der Poll, T.

    1999-01-01

    Tumor necrosis factor-alpha (TNF-alpha) is released from the cell surface by cleavage of pro-TNF-alpha by metalloproteinases (MPs). In cell cultures, inhibition of MPs has been found not only to reduce the release of TNF-alpha, but also to enhance the surface expression of TNF-alpha and TNF-alpha

  13. Letter: Prostaglandins and pre-eclampsia.

    Science.gov (United States)

    Calder, A A; Bonnar, J; Sheppard, B; Embrey, M P; Turnbull, A C

    1974-07-06

    Professor Brosens and colleagues (April 27, p.808) questions the safety of prostaglandins (PGs) for the induction of labor when pregnancy is complicated by hypertensive states, especially preeclampsia. Objections are based on the possibility that the uteroplacental bloodflow, which may already be compromised in these situations, could be further reduced by vasoconstrictive effects of the PGs on uterine, placental, and umbilical vessels. We have been using PGs extensively in this department and for the past year have been carrying out a double-blind trial of PGE2 and oxytocin by intravenous infusion after amniotomy for induction of labor in primigravidae. In 23 of the patients included thus far, labor was induced between 36 and 38 weeks because of moderate or severe preeclampsia. Of these, 12 have received oxytocin and 11 PGE2. In all cases, elective epidural analgesia has been employed and continuous fetal heartrate and intrauterine pressure recordings performed throughout. 1 patient in the group required an emergency cesarean section because of fetal distress; 2 others (1 from each group) were delivered by cesarean section because of failure to progress in labor. The remainder delivered vaginally with no evidence of increased incidence of fetal distress in the PG group. No perinatal deaths occurred. In an additional 18 primigravidae labor was induced at 36-38 weeks because of hypertensive complications of pregnancy by local PGE2 administration as previously described. These patients were assessed as clinically unfavorable for induction. 2 patients developed fetal distress and required cesarean sections; the others delivered vaginally. Experience with PGF2alpha is much less extensive but there is no reason to believe that this compound would behave differently, except with regard to maternal side effects. Thus it seems beneficial to use PGs for inducing labor in pregnancies complicated by hypertension and preeclampsia; no evidence of the suggested theoretical

  14. 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.

  15. 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.

  16. 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.

  17. In vitro alpha-amylase inhibition and in vivo antioxidant potential of Momordica dioica seeds in streptozotocin-induced oxidative stress in diabetic rats

    Directory of Open Access Journals (Sweden)

    P. Sailaja Rao

    2017-09-01

    Full Text Available Momordica dioica Roxb. Commonly known as “Kakora” in Telugu, is used in the Indian traditional system of medicine for the treatment of diabetes. The aim of this study was to investigate the antidiabetic activity of methanolic extract of M. dioica seeds (MEMD in streptozotocin (STZ induced diabetic rats. The in vitro α-amylase inhibitory activity of the MEMD was done by spectrophotometric method. Diabetes was induced by STZ (45 mg/kg; i.p, MEMD (100 & 200 mg/kg; b.wt and standard drug metformin (50 mg/kg; b.wt were administered to the diabetic rats. Blood glucose was estimated on the 11th day and the level of MDA, SOD and CAT was estimated in the liver tissue homogenate after the 15 days of experimental period. MEMD showed significant inhibition of alpha amylase activity and the IC50 was found to be 48 μg/ml. Oral administration of MEMD significantly reduced blood glucose level (P < 0.05, diminished the MDA level and refurbished depleted antioxidant enzymes and Insulin level to normalcy. These findings revealed that M. dioica seeds possess antihyperglycemic, antioxidant and anti lipid peroxidative activity and thus mitigate STZ-induced oxidative damage.

  18. Resveratrol prevents bradykinin-induced contraction of rat urinary bladders by decreasing prostaglandin production and calcium influx.

    Science.gov (United States)

    Tsuda, Yo; Nakahara, Tsutomu; Mori, Asami; Sakamoto, Kenji; Ishii, Kunio

    2011-09-01

    Resveratrol, a polyphenol found in grapes and peanuts, exerts beneficial effects on a number of diseases of cardiovascular and central nervous system. However, effects of resveratrol on the urinary system have not been fully investigated. In the present study, we examined effects of resveratrol on bradykinin-induced contraction and release of prostaglandin E2 in isolated rat urinary bladders. The effects of resveratrol on contractions induced by several agonists (prostaglandin E2, prostaglandin F2α and carbachol) and high K+ were also examined. We found that resveratrol concentration-dependently reduced the bradykinin-induced contraction in the rat urinary bladder preparations. The higher concentration of resveratrol (100 μM) abolished the bradykinin-induced prostaglandin E2 release. Similar results were obtained when the cyclooxygenase inhibitor indomethacin (10 μM) was used instead of resveratrol. Resveratrol also attenuated the prostaglandin E2-, prostaglandin F2α-, and to a lesser extent carbachol-induced contractions. Contractile responses to bradykinin, prostaglandin E2 and carbachol were largely prevented by blockade of Ca2+ channels with diltiazem. Both resveratrol and diltiazem prevented contractions induced by an addition of Ca2+ (2.5- 10 mM) into Ca2+-free/50 mMK+ solution or by 50 mMK+ solution containing normal Ca2+ (2.5 mM). These results suggest that resveratrol prevents bradykinin-induced contractions by attenuating not only the production of prostaglandins but also actions of them. The effect of resveratrol on contractile actions seems to be in part due to inhibition of Ca2+ influx. Because bradykinin plays an important role in pathological conditions of urinary bladder function, resveratrol may exert beneficial effects on the urinary bladder diseases.

  19. Rho iso-alpha acids from hops inhibit the GSK-3/NF-κB pathway and reduce inflammatory markers associated with bone and cartilage degradation

    Directory of Open Access Journals (Sweden)

    Bland Jeffrey S

    2009-08-01

    Full Text Available Abstract Background Rho iso-alpha acids (RIAA from hops have been shown to have anti-inflammatory properties. To understand the mechanisms, we evaluated the effect of RIAA in cell signaling pathways and inflammatory markers using various in vitro models. We also investigated their therapeutic effect in mice with collagen-induced arthritis. Methods The LPS-stimulated RAW 264.7 macrophages were used to evaluate the effect of RIAA on the NF-κB and MAPK signaling pathways; phosphorylation of ERK1/2, p38 and JNK was assessed by western blotting and NF-κB binding by electrophoretic mobility shift assays. Effect on the NF-κB activity was evaluated by the luciferase reporter assays in LPS-stimulated RAW 264.7 cells. GSK-3α/β kinase activity was measured in cell-free assays. The inhibitory effect of RIAA on inflammatory markers was assessed by measuring nitric oxide in LPS-stimulated RAW 264.7 cells, RANKL-mediated TRAP activity in transformed osteoclasts, and TNF-α/IL-1β-mediated MMP-13 expression in SW1353 cells. Mice with collagen-induced arthritis were fed with RIAA for 2 weeks. Symptoms of joint swelling, arthritic index and joint damage were assessed. Results RIAA selectively inhibited the NF-κB pathway while having no effect on ERK1/2, p38 and JNK phosphorylation in LPS-stimulated RAW 264.7 cells. RIAA also inhibited GSK-3α/β kinase activity and GSK-3β dependent phosphorylation of β-catenin in RAW 264.7 cells. In addition, RIAA inhibited NF-κB-mediated inflammatory markers in various cell models, including nitric oxide in LPS-stimulated RAW 264.7 cells, RANKL-mediated TRAP activity in transformed osteoclasts, and TNF-α/IL-1β-mediated MMP-13 expression in SW1353 human chondrosarcoma cells. Finally, in a mouse model of collagen-induced arthritis, RIAA ameliorated joint damage as evidenced by significant reduction of the arthritis index and histology score; at 250 mg/kg-body weight, RIAA had efficacy similar to that of 20 mg

  20. Estimation and characterization of prostaglandins in the human gastrointestinal tract

    Science.gov (United States)

    Bennett, A.; Stamford, I.F.; Stockley, Helen L.

    1977-01-01

    1 Prostaglandin-like material was extracted from muscle and mucosa of surgically removed human stomach, ileum and colon and assayed against prostaglandin E2 on strips of rat gastric fundus. Superfused human isolated gastric mucosa released prostaglandin-like material and release was increased by stretching or clamping the tissue. 2 The relative amounts of extracted biological activity were broadly as follows: gastric antral mucosa > colon muscle > gastric body mucosa ≈ ileal mucosa > colon mucosa ≈ gastric muscle ≈ ileal muscle. 3 Prostaglandin E and F were tentatively identified by chromatography and sensitivity to inactivation by alkali. 4 Prostaglandin E apparently contributed most to the biological activity, possibly because the assay tissue is more sensitive to prostaglandin E than to F. Chromatography of gastric body mucosal extracts located material running with prostaglandin E2 and a little with E1. Colonic muscle and mucosal extracts contained material with RF values of prostaglandins E1, E2, E3 and F1a, whereas F2a and F3a-like substances were found only in the mucosa. The proportions of prostaglandin F varied between specimens. 5 The amount of extracted prostaglandin-like activity was increased by adding cofactors and arachidonic acid, and lessened by homogenization with acid-ethanol. 6 The type and amount of activity generated from arachidonic acid by partly purified colonic mucosal prostaglandin synthetase depended on the substrate concentration. 7 The possible relationships of prostaglandins to mucus secretion and other physiological and pathological gut functions are discussed. PMID:597665

  1. Prostaglandins for adult liver transplanted patients.

    Science.gov (United States)

    Cavalcanti, Alexandre B; De Vasconcelos, Camila Paiva; Perroni de Oliveira, Mariana; Rother, Edna T; Ferraz, Leonardo

    2011-11-09

    Prostaglandins may reduce ischaemic injury after liver transplantation. Several small randomised trials have evaluated the effects of prostaglandins in patients undergoing liver transplantation. Results of these trials are inconsistent, and none has enough power to reliably exclude effects of prostaglandins. To assess the benefits and harms of prostaglandin E1 or E2 in adult liver-transplanted patients. We searched The Cochrane Hepato-Biliary Group Controlled Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library, MEDLINE, EMBASE, Science Citation Index Expanded, and LILACS (search on 20 April 2011). In addition, we perused the reference lists of the identified studies and contacted trials investigators, and national and international experts in order to identify more trials for the review. We included randomised clinical trials evaluating prostaglandin E1 or E2 initiated in the perioperative period versus placebo or standard treatment for adult patients undergoing liver transplantation. We did not apply any language or publication status restrictions. Two authors independently evaluated methodological quality, ie, risk of bias of the included trials, and extracted data using standardised data extraction forms. We contacted trial investigators in attempt to retrieve information not available in the original manuscripts. We used random-effects model meta-analyses and fixed-effect model meta-analyses to estimate the odds ratio with 95% confidence interval (CI). We included ten trials in which 652 patients were randomised. The risk of bias was considered high in most trials. There was no significant effect of prostaglandins on all-cause mortality (37/298[12.4%] in prostaglandin group versus 47/312[15.1%] in control group; OR 0.84, 95% CI 0.53 to 1.37; I(2) = 0%), on primary non-function of the allograft (8/238 [3.4%] versus. 16/250[6.4%] ;OR 0.55, 95% CI 0.23 to 1.33; I(2) = 0%), and on liver re-transplantation (12

  2. 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.

  3. Prostaglandins can modify gamma-radiation and chemical induced cytotoxicity and genetic damage in vitro and in vivo

    Energy Technology Data Exchange (ETDEWEB)

    Das, U.N.; Ramadevi, G.; Rao, K.P.; Rao, M.S. (Nizam' s Institute of Medical Sciences, Hyderabad (India))

    1989-12-01

    The effect of prostaglandin E1, E2, and F2 alpha on gamma-radiation, benzo(a)pyrene and diphenylhydantoin-induced cytotoxicity in vivo and genotoxicity in vitro was investigated. Prostaglandin E1 prevented both cytotoxic and genotoxic actions of all the three agents, where as both PGE2 and PGF2 alpha were ineffective. In fact, it was seen that both PGE2 and PGF2 alpha are genotoxic by themselves. Gamma-linolenic acid and dihomogamma-linolenic acid, the precursor of PGE1 were also as protective as that of PGE1, where as arachidonic acid, the precursor of 2 series PGs, has genotoxic actions to human lymphocytes in vitro. These results suggest that prostaglandins and their precursors can determine the susceptibility of cells to cytotoxic and genotoxic actions of chemicals and radiation. This study is particularly interesting since, it is known that some tumor cells contain excess of PGE2 and PGF2 alpha and many carcinogens can augment the synthesis of 2 series of PGs.

  4. Prostaglandins can modify gamma-radiation and chemical induced cytotoxicity and genetic damage in vitro and in vivo

    International Nuclear Information System (INIS)

    Das, U.N.; Ramadevi, G.; Rao, K.P.; Rao, M.S.

    1989-01-01

    The effect of prostaglandin E1, E2, and F2 alpha on gamma-radiation, benzo(a)pyrene and diphenylhydantoin-induced cytotoxicity in vivo and genotoxicity in vitro was investigated. Prostaglandin E1 prevented both cytotoxic and genotoxic actions of all the three agents, where as both PGE2 and PGF2 alpha were ineffective. In fact, it was seen that both PGE2 and PGF2 alpha are genotoxic by themselves. Gamma-linolenic acid and dihomogamma-linolenic acid, the precursor of PGE1 were also as protective as that of PGE1, where as arachidonic acid, the precursor of 2 series PGs, has genotoxic actions to human lymphocytes in vitro. These results suggest that prostaglandins and their precursors can determine the susceptibility of cells to cytotoxic and genotoxic actions of chemicals and radiation. This study is particularly interesting since, it is known that some tumor cells contain excess of PGE2 and PGF2 alpha and many carcinogens can augment the synthesis of 2 series of PGs

  5. The E3 Ubiquitin Ligase- and Protein Phosphatase 2A (PP2A)-binding Domains of the Alpha4 Protein Are Both Required for Alpha4 to Inhibit PP2A Degradation

    Energy Technology Data Exchange (ETDEWEB)

    LeNoue-Newton, Michele; Watkins, Guy R.; Zou, Ping; Germane, Katherine L.; McCorvey, Lisa R.; Wadzinski, Brian E.; Spiller, Benjamin W. (Vanderbilt)

    2012-04-30

    Protein phosphatase 2A (PP2A) is regulated through a variety of mechanisms, including post-translational modifications and association with regulatory proteins. Alpha4 is one such regulatory protein that binds the PP2A catalytic subunit (PP2Ac) and protects it from polyubiquitination and degradation. Alpha4 is a multidomain protein with a C-terminal domain that binds Mid1, a putative E3 ubiquitin ligase, and an N-terminal domain containing the PP2Ac-binding site. In this work, we present the structure of the N-terminal domain of mammalian Alpha4 determined by x-ray crystallography and use double electron-electron resonance spectroscopy to show that it is a flexible tetratricopeptide repeat-like protein. Structurally, Alpha4 differs from its yeast homolog, Tap42, in two important ways: (1) the position of the helix containing the PP2Ac-binding residues is in a more open conformation, showing flexibility in this region; and (2) Alpha4 contains a ubiquitin-interacting motif. The effects of wild-type and mutant Alpha4 on PP2Ac ubiquitination and stability were examined in mammalian cells by performing tandem ubiquitin-binding entity precipitations and cycloheximide chase experiments. Our results reveal that both the C-terminal Mid1-binding domain and the PP2Ac-binding determinants are required for Alpha4-mediated protection of PP2Ac from polyubiquitination and degradation.

  6. a randomised controlled trial oftwo prostaglandin regitnens

    African Journals Online (AJOL)

    Design. A prospective randomised controlled trial. Setting. Department of Obstetrics and Gynae- ... hours after the original administration of either prostaglandin regimen. If abortion had not taken place 36 .... Tygerberg Hospital for permission to publish, and Upjohn. (Pry) Ltd for supplying the Prepidil gel used in the study. 1.

  7. Adenosine contributes to blood flow regulation in the exercising human leg by increasing prostaglandin and nitric oxide formation

    DEFF Research Database (Denmark)

    Mortensen, Stefan; Nyberg, Michael; Thaning, Pia

    2009-01-01

    in synergy to regulate skeletal muscle hyperemia by determining the following: (1) the effect of adenosine receptor blockade on skeletal muscle exercise hyperemia with and without simultaneous inhibition of prostaglandins (indomethacin; 0.8 to 1.8 mg/min) and NO (N(G)-mono-methyl-l-arginine; 29 to 52 mg...

  8. Lipopolysaccharide and Tumor Necrosis Factor Alpha Inhibit Interferon Signaling in Hepatocytes by Increasing Ubiquitin-Like Protease 18 (USP18) Expression.

    Science.gov (United States)

    MacParland, Sonya A; Ma, Xue-Zhong; Chen, Limin; Khattar, Ramzi; Cherepanov, Vera; Selzner, Markus; Feld, Jordan J; Selzner, Nazia; McGilvray, Ian D

    2016-06-15

    Inflammation may be maladaptive to the control of viral infection when it impairs interferon (IFN) responses, enhancing viral replication and spread. Dysregulated immunity as a result of inappropriate innate inflammatory responses is a hallmark of chronic viral infections such as, hepatitis B virus and hepatitis C virus (HCV). Previous studies from our laboratory have shown that expression of an IFN-stimulated gene (ISG), ubiquitin-like protease (USP)18 is upregulated in chronic HCV infection, leading to impaired hepatocyte responses to IFN-α. We examined the ability of inflammatory stimuli, including tumor necrosis factor alpha (TNF-α), lipopolysaccharide (LPS), interleukin-6 (IL-6) and IL-10 to upregulate hepatocyte USP18 expression and blunt the IFN-α response. Human hepatoma cells and primary murine hepatocytes were treated with TNF-α/LPS/IL-6/IL-10 and USP18, phosphorylated (p)-STAT1 and myxovirus (influenza virus) resistance 1 (Mx1) expression was determined. Treatment of Huh7.5 cells and primary murine hepatocytes with LPS and TNF-α, but not IL-6 or IL-10, led to upregulated USP18 expression and induced an IFN-α refractory state, which was reversed by USP18 knockdown. Liver inflammation was induced in vivo using a murine model of hepatic ischemia/reperfusion injury. Hepatic ischemia/reperfusion injury led to an induction of USP18 expression in liver tissue and promotion of lymphocytic choriomeningitis replication. These data demonstrate that certain inflammatory stimuli (TNF-α and LPS) but not others (IL-6 and IL-10) target USP18 expression and thus inhibit IFN signaling. These findings represent a new paradigm for how inflammation alters hepatic innate immune responses, with USP18 representing a potential target for intervention in various inflammatory states. Inflammation may prevent the control of viral infection when it impairs the innate immune response, enhancing viral replication and spread. Blunted immunity as a result of inappropriate innate

  9. Nuclear factor-kappa B family member RelB inhibits human immunodeficiency virus-1 Tat-induced tumor necrosis factor-alpha production.

    Directory of Open Access Journals (Sweden)

    Michelle Kiebala

    2010-07-01

    Full Text Available Human Immunodeficiency Virus-1 (HIV-1-associated neurocognitive disorder (HAND is likely neuroinflammatory in origin, believed to be triggered by inflammatory and oxidative stress responses to cytokines and HIV protein gene products such as the HIV transactivator of transcription (Tat. Here we demonstrate increased messenger RNA for nuclear factor-kappa B (NF-kappaB family member, transcription factor RelB, in the brain of doxycycline-induced Tat transgenic mice, and increased RelB synthesis in Tat-exposed microglial cells. Since genetic ablation of RelB in mice leads to multi-organ inflammation, we hypothesized that Tat-induced, newly synthesized RelB inhibits cytokine production by microglial cells, possibly through the formation of transcriptionally inactive RelB/RelA complexes. Indeed, tumor necrosis factor-alpha (TNFalpha production in monocytes isolated from RelB deficient mice was significantly higher than in monocytes isolated from RelB expressing controls. Moreover, RelB overexpression in microglial cells inhibited Tat-induced TNFalpha synthesis in a manner that involved transcriptional repression of the TNFalpha promoter, and increased phosphorylation of RelA at serine 276, a prerequisite for increased RelB/RelA protein interactions. The Rel-homology-domain within RelB was necessary for this interaction. Overexpression of RelA itself, in turn, significantly increased TNFalpha promoter activity, an effect that was completely blocked by RelB overexpression. We conclude that RelB regulates TNFalpha cytokine synthesis by competitive interference binding with RelA, which leads to downregulation of TNFalpha production. Moreover, because Tat activates both RelB and TNFalpha in microglia, and because Tat induces inflammatory TNFalpha synthesis via NF-kappaB, we posit that RelB serves as a cryoprotective, anti-inflammatory, counter-regulatory mechanism for pathogenic NF-kappaB activation. These findings identify a novel regulatory pathway for

  10. CP-25, a Novel Anti-inflammatory and Immunomodulatory Drug, Inhibits the Functions of Activated Human B Cells through Regulating BAFF and TNF-alpha Signaling and Comparative Efficacy with Biological Agents

    Directory of Open Access Journals (Sweden)

    Feng Zhang

    2017-12-01

    Full Text Available Paeoniflorin-6′-O-benzene sulfonate (code: CP-25 was the chemistry structural modifications of Paeoniflorin (Pae. CP-25 inhibited B cells proliferation stimulated by B cell activating factor belonging to the TNF family (BAFF or Tumor necrosis factor alpha (TNF-alpha. CP-25, Rituximab and Etanercept reduced the percentage and numbers of CD19+ B cells, CD19+CD20+ B cells, CD19+CD27+ B cells and CD19+CD20+CD27+ B cells induced by BAFF or TNF-alpha. There was significant difference between CP-25 and Rituximab or CP-25 and Etanercept. CP-25 down-regulated the high expression of BAFFR, BCMA, and TACI stimulated by BAFF or TNF-alpha. The effects of Rituximab and Etanercept on BAFFR or BCMA were stronger than that of CP-25. CP-25, Rituximab and Etanercept down-regulated significantly the expression of TNFR1 and TNFR2 on B cell stimulated by BAFF or TNF-alpha. CP-25, Rituximab and Etanercept down-regulated the expression of MKK3, P-p38, P-p65, TRAF2, and p52 in B cells stimulated by BAFF and the expression of TRAF2 and P-p65 in B cells stimulated by TNF-alpha. These results suggest that CP-25 regulated moderately activated B cells function by regulating the classical and alternative NF-κB signaling pathway mediated by BAFF and TNF-alpha-TRAF2-NF-κB signaling pathway. This study suggests that CP-25 may be a promising anti-inflammatory immune and soft regulation drug.

  11. CP-25, a Novel Anti-inflammatory and Immunomodulatory Drug, Inhibits the Functions of Activated Human B Cells through Regulating BAFF and TNF-alpha Signaling and Comparative Efficacy with Biological Agents.

    Science.gov (United States)

    Zhang, Feng; Shu, Jin-Ling; Li, Ying; Wu, Yu-Jing; Zhang, Xian-Zheng; Han, Le; Tang, Xiao-Yu; Wang, Chen; Wang, Qing-Tong; Chen, Jing-Yu; Chang, Yan; Wu, Hua-Xun; Zhang, Ling-Ling; Wei, Wei

    2017-01-01

    Paeoniflorin-6'- O -benzene sulfonate (code: CP-25) was the chemistry structural modifications of Paeoniflorin (Pae). CP-25 inhibited B cells proliferation stimulated by B cell activating factor belonging to the TNF family (BAFF) or Tumor necrosis factor alpha (TNF-alpha). CP-25, Rituximab and Etanercept reduced the percentage and numbers of CD19 + B cells, CD19 + CD20 + B cells, CD19 + CD27 + B cells and CD19 + CD20 + CD27 + B cells induced by BAFF or TNF-alpha. There was significant difference between CP-25 and Rituximab or CP-25 and Etanercept. CP-25 down-regulated the high expression of BAFFR, BCMA, and TACI stimulated by BAFF or TNF-alpha. The effects of Rituximab and Etanercept on BAFFR or BCMA were stronger than that of CP-25. CP-25, Rituximab and Etanercept down-regulated significantly the expression of TNFR1 and TNFR2 on B cell stimulated by BAFF or TNF-alpha. CP-25, Rituximab and Etanercept down-regulated the expression of MKK3, P-p38, P-p65, TRAF2, and p52 in B cells stimulated by BAFF and the expression of TRAF2 and P-p65 in B cells stimulated by TNF-alpha. These results suggest that CP-25 regulated moderately activated B cells function by regulating the classical and alternative NF-κB signaling pathway mediated by BAFF and TNF-alpha-TRAF2-NF-κB signaling pathway. This study suggests that CP-25 may be a promising anti-inflammatory immune and soft regulation drug.

  12. Anticonvulsive effects of endogenous prostaglandins formed in brain of spontaneously convulsing gerbils.

    Science.gov (United States)

    Förstermann, U; Seregi, A; Hertting, G

    1984-06-01

    Seizures were induced in a strain of epileptic gerbils by moderate environmental stress. Concentrations of five different cyclooxygenase products (PGD2, PGF2 alpha, PGE2, 6-keto-PGF1 alpha and thromboxane B2) were measured in brain by specific radioimmunoassays before and at different time intervals after the onset of clonic-tonic convulsions. All prostanoids markedly increased subsequent to the convulsions. Maximal concentrations were reached after about 15 min. The major compound detected was PGD2, followed by PGF2 alpha and lower concentrations of the other cyclooxygenase products. Indomethacin completely prevented the convulsion-induced formation of prostanoids. Fifteen min after a first seizure almost all animals proved to be protected against a second convulsion. Indomethacin pretreatment markedly reduced the number of convulsion-resistant animals. These findings are compatible with the hypothesis that endogenous prostaglandins exert anticonvulsive effects.

  13. Intracervical prostaglandins for induction of labour.

    Science.gov (United States)

    Boulvain, M; Kelly, A; Irion, O

    2008-01-23

    Prostaglandins have been used for cervical ripening and induction of labour since the 1970s. The goal of the administration of prostaglandins in the process of induction of labour is to achieve cervical ripening before the onset of contractions. One of the routes of administration that was proposed is intracervical. Using this route, prostaglandins are less easy to administer and the need for exposing the cervix may cause discomfort to the woman. To determine the effects of intracervical prostaglandins for third trimester cervical ripening or induction of labour compared with placebo/no treatment and with vaginal prostaglandins (except misoprostol). We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (August 2007) and bibliographies of relevant papers. Clinical trials comparing intracervical prostaglandins used for third trimester cervical ripening or labour induction with placebo/no treatment or other methods listed above it on a predefined list of labour induction methods (vaginal prostaglandins, except misoprostol). A strategy was developed to deal with the large volume and complexity of trial data relating to labour induction. This involved a two-stage method of data extraction. Fifty-six trials (7738 women) are included. INTRACERVICAL PGE2 WITH PLACEBO/NO TREATMENT: 28 TRIALS, 3764 WOMEN: Four studies reported the number of women who did not achieve vaginal delivery within 24 hours, showing a decreased risk with PGE2 (relative risk (RR) 0.61; 95% confidence interval (CI) 0.47 to 0.79). There was a small, and statistically non-significant, reduction of the risk of caesarean section when PGE2 was used (RR 0.88; 95% CI 0.77 to 1.00). The finding was statistically significant in a subgroup of women with intact membranes and unfavourable cervix only (RR 0.82; 95% CI 0.68 to 0.98). The risk of hyperstimulation with fetal heart rate (FHR) changes was not significantly increased (RR 1.21; 95% CI 0.72 to 2.05). However, the risk of

  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

    2014-01-01

    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 prostaglanding 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. PMID:25114122

  15. 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.

  16. Molecular cloning and spatiotemporal expression of prostaglandin F synthase and microsomal prostaglandin E synthase-1 in porcine endometrium.

    Science.gov (United States)

    Waclawik, Agnieszka; Rivero-Muller, Adolfo; Blitek, Agnieszka; Kaczmarek, Monika M; Brokken, Leon J S; Watanabe, Kikuko; Rahman, Nafis A; Ziecik, Adam J

    2006-01-01

    Endometrial prostaglandins (PGs) and the PGE2/PGF2alpha ratio play an important role in regulating the estrous cycle and establishment of pregnancy. The enzymes downstream of cyclooxygenase-2 may determine the PGE2/PGF2alpha ratio in the porcine uterus. Thus, we have cloned porcine PGF synthase (PGFS) and microsomal PGE synthase-1 (mPGES-1) and characterized their expression in porcine endometrium during the estrous cycle and early pregnancy. PGFS and mPGES-1 amino acid sequences possessed a high degree (>67% and >77%, respectively) of identity with the other mammalian homologs. There was little modulation of mPGES-1 throughout the estrous cycle; however, PGFS expression was highly up-regulated in endometrium around the time of luteolysis. During early pregnancy, PGFS at the protein level showed a time-dependent increase (low on d 10-13, intermediate on d 14-23, and high on d 24-25). In pregnancy, expression of mPGES-1 was intermediate on d 10-11 and low on d 14-17 and then increased after d 22, reaching the maximum on d 24-25. Immunohistochemistry showed localization of PGFS and mPGES-1 proteins mainly in luminal and glandular epithelium. Concluding, the spatiotemporal expression of PGFS throughout the estrous cycle indicates an involvement of PGFS in regulating luteolysis in the pig. The comparison of endometrial PGFS and mPGES-1 expression on d 10-13 of the estrous cycle and pregnancy suggest a supportive role of these enzymes in determining the increase of uterine PGE2/PGF2alpha ratio during maternal recognition of pregnancy. Moreover, high expression of both PG synthases after initiation of implantation may indicate their significant role in placentation.

  17. Inhibition of Nitric Oxide and Prostaglandin E2 Expression by ...

    African Journals Online (AJOL)

    HP

    binding activity of NF-. κB in LPS-stimulated BV2 microglial cells and suppressed phosphorylation of ERK and JNK, which are involved in the mitogen-activated protein kinase (MAPK) signaling pathway for regulating pro- inflammatory genes.

  18. Prostaglandin receptors EP and FP are regulated by estradiol and progesterone in the uterus of ovariectomized rats

    Directory of Open Access Journals (Sweden)

    Blesson Chellakkan S

    2012-01-01

    Full Text Available Abstract Background Prostaglandins are important for female reproduction. Prostaglandin-E2 acts via four different receptor subtypes, EP1, EP2, EP3 and EP4 whereas prostaglandin-F2alpha acts through FP. The functions of prostaglandins depend on the expression of their receptors in different uterine cell types. Our aim was to investigate the expression of EPs and FP in rat uterus and to identify the regulation by estradiol, progesterone and estrogen receptor (ER selective agonists. Methods We performed four different rat experiments involving treatments with estradiol, progesterone and ER agonists. Real-time PCR and immunohistochemistry were employed to evaluate receptor expression. Results Our results showed that all mRNAs and proteins of EPs and FP are expressed in the rat uterus. The expression pattern and intensity of immunostaining vary between different cell types and treatments. The mRNA expression of all EPs and FP are downregulated by estradiol and the ERalpha specific agonist PPT, whereas the ERbeta specific agonist DPN downregulates only EP2 and EP4. The protein expression however, showed an increase in EP2 and EP3 after estradiol treatment. When treated with estradiol and progesterone in combination, the expressions of EP1 and EP3 are upregulated. Conclusions Regulation of EPs and FP expression by estradiol appears to be mainly modulated via ERalpha for EP1, EP3 and FP, while EP2 and EP4 also are affected by the ERbeta selective ligand. Our immunohistochemical data shows a cell specific regulation of prostaglandin receptors under the influence of ovarian steroids, where EP2 is estrogen regulated in all uterine tissues examined. EP1 and EP3 are upregulated by the combination of estradiol and progesterone. Thus, our observations indicate that estradiol and progesterone regulate the mRNA and protein expression of EPs and FP in a receptor and tissue specific way.

  19. IL-3R-alpha blockade inhibits tumor endothelial cell-derived extracellular vesicle (EV)-mediated vessel formation by targeting the β-catenin pathway.

    Science.gov (United States)

    Lombardo, Giusy; Gili, Maddalena; Grange, Cristina; Cavallari, Claudia; Dentelli, Patrizia; Togliatto, Gabriele; Taverna, Daniela; Camussi, Giovanni; Brizzi, Maria Felice

    2018-03-01

    The proangiogenic cytokine Interleukin-3 (IL-3) is released by inflammatory cells in breast and ovarian cancer tissue microenvironments and also acts as an autocrine factor for human breast and kidney tumor-derived endothelial cells (TECs). We have previously shown that IL-3-treated endothelial cells (ECs) release extracellular vesicles (EVs), which serve as a paracrine mechanism for neighboring ECs, by transferring active molecules. The impact of an anti-IL-3R-alpha blocking antibody on the proangiogenic effect of EVs released from TECs (anti-IL-3R-EVs) has therefore been investigated in this study. We have found that anti-IL-3R-EV treatment prevented neovessel formation and, more importantly, also induced the regression of in vivo TEC-derived neovessels. Two miRs that target the canonical wingless (Wnt)/β-catenin pathway, at different levels, were found to be differentially regulated when comparing the miR-cargo of naive TEC-derived EVs (EVs) and anti-IL-3R-EVs. miR-214-3p, which directly targets β-catenin, was found to be upregulated, whereas miR-24-3p, which targets adenomatous polyposis coli (APC) and glycogen synthase kinase-3β (GSK3β), was found to be downregulated. In fact, upon their transfer into the cell, low β-catenin content and high levels of the two members of the "β-catenin destruction complex" were detected. Moreover, c-myc downregulation was found in TECs treated with anti-IL-3R-EVs, pre-miR-214-3p-EVs and antago-miR-24-3p-EVs, which is consistent with network analyses of miR-214-3p and miR-24-3p gene targeting. Finally, in vivo studies have demonstrated the impaired growth of vessels in pre-miR-214-3p-EV- and antago-miR-24-3p-EV-treated animals. These effects became much more evident when combo treatment was applied. The results of the present study identify the canonical Wnt/β-catenin pathway as a relevant mechanism of TEC-derived EV proangiogenic action. Furthermore, we herein provide evidence that IL-3R blockade may yield some

  20. Changes in cyclooxygenase activity and prostaglandin profiles during monoamine metabolism in rat brain homogenates.

    Science.gov (United States)

    Seregi, A; Hertting, G

    1984-04-01

    The effect of different monoamine oxidase (MAO) substrates on the endogenous prostaglandin(PG) and thromboxane (TX) biosynthesis in rat brain homogenates was studied. In the absence of MAO substrates the following pattern of arachidonic acid metabolites was found: PGD2 greater than PGF2 alpha greater than TXB2 greater than PGE2 greater than or equal to 6ketoPGF1 alpha. Phenylethylamine(PEA) stimulated the cyclooxygenase activity 1.5-fold (expressed as the sum of the products formed), without altering the product profile. Tyrosine(Tyr) caused a twofold increase in cyclooxygenase activity and slightly modified the product composition (PGD2=PGF2 alpha greater than PGE2 greater than TXB2 greater than 6ketoPGF1 alpha). In the presence of noradrenaline(NA) there was a threefold stimulation of cyclooxygenase activity. The increase of PGF2 alpha was more pronounced than that of the other metabolites (PGF2 alpha greater than PGD2 greater than TXB2 greater than PGE2 greater than 6ketoPGF1 alpha). alpha-Methylnoradrenaline(alpha metNA ) (not a substrate for MAO but bearing the catechol group) altered the PG pattern in the same way as NA, but without enhancing the cyclooxygenase activity. PEA or Tyr when administered together with alpha metNA produced a NA-like effect both on the cyclooxygenase activity and on the product profile. The increase in cyclooxygenase activity was abolished by pargyline or by catalase, independently of the activator system used. The results support the hypothesis that NA-stimulation of brain PG (and TX) formation is mediated by H2O2 formed during the degradation of the amine via MAO. The role of the catechol group in protection of the cyclooxygenase against inactivation and in the changes of product composition, as well as the possible significance of the coupling between arachidonate and monoamine metabolism is discussed.

  1. 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...

  2. Tumor necrosis factor alpha inhibits the suppressive effect of regulatory T cells on the hepatitis B virus-specific immune response.

    Science.gov (United States)

    Stoop, Jeroen N; Woltman, Andrea M; Biesta, Paula J; Kusters, Johannes G; Kuipers, Ernst J; Janssen, Harry L A; van der Molen, Renate G

    2007-09-01

    Chronicity of hepatitis B virus (HBV) infection is characterized by a weak immune response to the virus. CD4+CD25+ regulatory T cells (Treg) are present in increased numbers in the peripheral blood of chronic HBV patients, and these Treg are capable of suppressing the HBV-specific immune response. The aim of this study was to abrogate Treg-mediated suppression of the HBV-specific immune response. Therefore, Treg and a Treg-depleted cell fraction were isolated from peripheral blood of chronic HBV patients. Subsequently, the suppressive effect of Treg on the response to HBV core antigen (HBcAg) and tetanus toxin was compared, and the effect of exogenous tumor necrosis factor alpha (TNF-alpha), interleukin-1-beta (IL-1beta), or neutralizing antibodies against interleukin-10 (IL-10) or transforming growth factor beta (TGF-beta) on Treg-mediated suppression was determined. The results show that Treg of chronic HBV patients had a more potent suppressive effect on the response to HBcAg compared with the response to tetanus toxin. Neutralization of IL-10 and TGF-beta or exogenous IL-1beta had no effect on Treg-mediated suppression of the anti-HBcAg response, whereas exogenous TNF-alpha partially abrogated Treg-mediated suppression. Preincubation of Treg with TNF-alpha demonstrated that TNF-alpha had a direct effect on the Treg. No difference was observed in the type II TNF receptor expression by Treg from chronic HBV patients and healthy controls. Treg-mediated suppression of the anti-HBV response can be reduced by exogenous TNF-alpha. Because chronic HBV patients are known to produce less TNF-alpha, these data implicate an important role for TNF-alpha in the impaired antiviral response in chronic HBV.

  3. A comparison of the biological activities of four prostaglandins

    Science.gov (United States)

    Horton, E. W.; Main, I. H. M.

    1963-01-01

    The biological activities of prostaglandins E1, E2, E3 and F1α have been compared. Prostaglandins E1, E2, E3 were qualitatively similar; E1 and E2 were about equiactive, but E3 was less active on all preparations. Prostaglandin F1α was a less potent vasodilator than E1 on the cat gastrocnemius muscle blood flow and skin blood flow and a less potent depressor drug on rabbit blood pressure. On the rabbit isolated jejunum F1α was twice as active as E1 but on the guinea-pig isolated ileum E1 was about forty times more active than F1α. One qualitative difference between these prostaglandins was observed; on the rabbit fallopian tube in vivo prostaglandins of the E series decreased both the tone and the peristalsis of the tube whereas prostaglandin F1α increased tubal tone. ImagesFig. 2Fig. 3Fig. 5 PMID:14066143

  4. The effects of some prostaglandins on respiration in anaesthetized cats

    Science.gov (United States)

    McQueen, D.S.

    1974-01-01

    1 Some prostaglandins have been found to be capable of affecting respiration in anaesthetized cats. 2 Prostaglandins E1, E2, F2α, A1 and A2 all elicited increases in respiratory frequency when administered to cats anaesthetized with either pentobarbitone or α-chloralose. This effect was abolished by bilateral vagotomy. 3 Prostaglandins of the E and A series, but not prostaglandin F2α, elicited increases in tidal volume which were accompanied by falls in systemic blood pressure in cats anaesthetized with pentobarbitone. The changes in blood pressure were also obtained in cats anaesthetized with α-chloralose, but not the tidal volume changes. 4 It is unlikely that the prostaglandins influenced respiration by direct actions on arterial chemoreceptors or baroreceptors. 5 Mechanisms by which the prostaglandins may be acting to affect respiration are discussed. PMID:4447858

  5. The role of prostaglandins in bone in vivo.

    Science.gov (United States)

    Norrdin, R W; Jee, W S; High, W B

    1990-11-01

    Prostaglandins of the E series, primarily E2 and E1, have the greatest activity in bone. Following discovery of their potent ability to stimulate bone resorption in vitro, clinical investigations have placed prostaglandins at sites of localized bone resorption associated with inflammatory or space occupying lesions in vivo. These studies have shown that prostaglandin production at such sites may be increased by cytokines such as interleukin-1 but the mechanisms by which prostaglandins stimulate bone resorption are not yet known. Observation of periosteal bone formation in patients given, pharmacological doses of prostaglandin has led to investigation of its bone forming activity. Young, growing rats have increased metaphyseal bone formation and this is accompanied by increased periosteal and endocortical bone formation in older animals. In the mature animals there is a generalized activation of remodelling with increased formation in the remodeling cycle. This is also seen in oophorectomized rats and results in repletion of the lost bone in this model of osteoporosis. In animal models of localized disuse osteopenia, prostaglandins are found to be elevated at the site of bone loss and prostaglandin inhibitors at least partially protect against the exaggerated resorption that occurs. This is also seen in models of orthodontic tooth movement, periodontitis and osteomyelitis. Prostaglandin synthesis inhibitors have been shown to delay healing of bone and this has led to limitations on their use clinically in some situations. Exogenously administered prostaglandins have been found to enhance periosteal callus formation, but healing is not uniformly enhanced. Prostaglandins have also been associated with hypercalcemia in certain animal tumors that model human hypercalcemia of malignancy but are probably most important in this condition as mediators in the localized resorption of bone at tumor sites. These in vivo studies have shown that prostaglandins are involved with

  6. Prostaglandins for management of retained placenta.

    Science.gov (United States)

    Grillo-Ardila, Carlos F; Ruiz-Parra, Ariel I; Gaitán, Hernando G; Rodriguez-Malagon, Nelcy

    2014-05-16

    Retained placenta affects 0.5% to 3% of women following delivery and it is a major cause of maternal death due to postpartum haemorrhage. Usually, retained placenta has been managed by manual removal or curettage under anaesthesia, which may be associated with haemorrhage, infection and uterine perforation. Medical management to facilitate the delivery of the retained placenta could be a safe alternative avoiding surgical intervention. To assess the effectiveness and safety of prostaglandins for the management of retained placenta. We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (1 December 2013), LILACS (1982 to 1 December 2013), SciELO (1998 to 1 December 2013), Web of Science (2001 to 1 December 2013), openSIGLE (1997 to 1 December 2013), World Health Organization International Clinical Trials Registry Platform (ICTRP) (1 December 2013) and the metaRegister of Controlled Trials (mRCT) (1 December 2013). We also contacted authors of included studies and reviewed the reference lists of retrieved studies. Randomised controlled clinical trials comparing the use of prostaglandins (or prostaglandin analogues) with placebo, expectant management, tocolytic drugs, any other prostaglandins or surgical interventions for the management of retained placenta after vaginal delivery of singleton live infants of 20 or more weeks of gestation. Two review authors independently assessed trials for inclusion and assessed trial quality. Two review authors independently extracted data. Data were checked for accuracy. Any disagreements were resolved through consensus or consultation with a third review author when required. Authors of the included studies were contacted for additional information. We included three trials, involving 244 women. The studies were considered to be at high risk of bias.The prostaglandins used were PG E2 analogue (sulprostone) in 50 participants and PG E1 analogue (misoprostol) in 194 participants at a dose of 250 mcg and 800 mcg

  7. Endocannabinoids and prostaglandins both contribute to GnRH neuron-GABAergic afferent local feedback circuits

    Science.gov (United States)

    Glanowska, Katarzyna M.

    2011-01-01

    Gonadotropin-releasing hormone (GnRH) neurons form the final common pathway for central control of fertility. Regulation of GnRH neurons by long-loop gonadal steroid feedback through steroid receptor-expressing afferents such as GABAergic neurons is well studied. Recently, local central feedback circuits regulating GnRH neurons were identified. GnRH neuronal depolarization induces short-term inhibition of their GABAergic afferents via a mechanism dependent on metabotropic glutamate receptor (mGluR) activation. GnRH neurons are enveloped in astrocytes, which express mGluRs. GnRH neurons also produce endocannabinoids, which can be induced by mGluR activation. We hypothesized the local GnRH-GABA circuit utilizes glia-derived and/or cannabinoid mechanisms and is altered by steroid milieu. Whole cell voltage-clamp was used to record GABAergic postsynaptic currents (PSCs) from GnRH neurons before and after action potential-like depolarizations were mimicked. In GnRH neurons from ovariectomized (OVX) mice, this depolarization reduced PSC frequency. This suppression was blocked by inhibition of prostaglandin synthesis with indomethacin, by a prostaglandin receptor antagonist, or by a specific glial metabolic poison, together suggesting the postulate that prostaglandins, potentially glia-derived, play a role in this circuit. This circuit was also inhibited by a CB1 receptor antagonist or by blockade of endocannabinoid synthesis in GnRH neurons, suggesting an endocannabinoid element, as well. In females, local circuit inhibition persisted in androgen-treated mice but not in estradiol-treated mice or young ovary-intact mice. In contrast, local circuit inhibition was present in gonad-intact males. These data suggest GnRH neurons interact with their afferent neurons using multiple mechanisms and that these local circuits can be modified by both sex and steroid feedback. PMID:21917995

  8. Regulation of cyclic AMP metabolism by prostaglandins in rabbit cortical collecting tubule cells

    International Nuclear Information System (INIS)

    Sonnenburg, W.K.

    1987-01-01

    In the rabbit cortical collecting tubule (RCCT), prostaglandin E 1 (PGE 1 ) and prostaglandin E 2 (PGE 2 ) at 1 nM inhibit arginine-vasopressin (AVP)-induced water reabsorption, while 100 nM PGE 1 and PGE 2 alone stimulate water reabsorption. Reported here are studies designed to investigate the molecular basis for the biphasic physiological action of PGE 1 and PGE 2 in the collecting duct. In freshly isolated RCCT cells, PGE 1 , PGE 2 , and 16,16-dimethyl-PGE 2 (DM-PGE 2 ) stimulated cAMP synthesis at concentrations ranging from 0.1 to 10 M. Other prostaglandins including the synthetic PGE 2 analogue, sulprostone, failed to stimulate cAMP synthesis. Moreover, sulprostone did not antagonize PGE 2 -stimulated cAMP formation. In contrast, PGE 2 and sulprostone at concentrations ranging from 1 to 100 nM, inhibited AVP-induced cAMP accumulation in freshly isolated RCCT cells. PGE 2 , PGE 1 , DM-PGE 2 and sulprostone at 100 nM were equally effective in inhibiting AVP-induced cAMP formation. Moreover sulprostone inhibited AVP-stimulated adenylate cyclase activity. These results suggest that PGE derivatives mediate either inhibition or activation of adenylate cyclase by stimulating different PGE receptors. To further test this concept, PGE 2 binding to freshly isolated RCCT cell membranes was characterized. Two different classes of PGE 2 binding were detected. / 3 H/PGE 2 binding to the high affinity class of sites was increased by the GTP-analogue, GTP S, while pertussis toxin pretreatment blocked the stimulatory action. In contrast, / 3 H/ PGE 2 binding to the low affinity class of sites was decreased by GTP S; this inhibitory effect was not blocked by pertussis toxin pretreatment

  9. Prostaglandins - universal biological regulators in the human body (literature review

    Directory of Open Access Journals (Sweden)

    О. V. Tymoshchuk

    2018-02-01

    Full Text Available Recently, researchers of different industries pay great attention to the problem of prostaglandins. Objective: to study and systematize the basic questions of structure, biological action and metabolism of prostaglandins in the human body and using their analogues in pharmacy through the domestic and foreign literature data analysis. Prostaglandins – biologically active substances which are similar in effect to hormones, but are synthesized in cells of different tissues. Prostaglandins as universal cellular mediators are widely distributed in the body, synthesized in small amounts in almost all tissues, have both local and systemic effects. For each prostaglandin there is a target organ. On chemical structure they are small molecules related to eicosanoids - a group of fat-like substances (lipids. Depending on the chemical structure prostaglandins are divided into series (A, B, C, D, E, F, G, H, I and J and three groups (1–3; type F isomers are to be indicated by additional letters α and β. Prostaglandins have an extremely wide range of physiological effects in the body and have three main functions: supporting, molecular, neurotransmitter. Most prostaglandins interact with specific receptors of plasma membranes, but some prostaglandins (group A can act without receptors. There is no stock of prostaglandins in the body, their life cycle is short, and they are quickly produced in response to biological stimulants exposure, have their effect in extremely small quantity and are rapidly inactivated in the bloodstream. Due to the extremely rapid breakdown of prostaglandins in the body they work near their place of secretion. Preparations of prostaglandins and their derivatives are used in experimental and clinical medicine for abortion and induction of labor, treatment of stomach ulcers, asthma, certain heart diseases, congenital heart defects in newborns, glaucoma, atherosclerosis, rheumatic and neurological diseases, kidney diseases, diabetes

  10. 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.

  11. Regulation of prostaglandin E2 synthesis after brain irradiation

    International Nuclear Information System (INIS)

    Moore, Amy H.; Olschowka, John A.; Williams, Jacqueline P.; Okunieff, Paul; O'Banion, M. Kerry

    2005-01-01

    Purpose: A local tissue reaction, termed neuroinflammation, occurs after irradiation of brain tissue. Previous work suggested that cyclooxygenase (COX)-2 activity was important for changes in gene expression associated with neuroinflammation as well as increased prostaglandin E 2 (PGE 2 ) levels seen after radiation treatment. Methods and materials: To begin to determine the contributions of other enzymes involved in PGE 2 production, we examined protein levels of COX-1 and COX-2 as well as 2 PGE synthases (membrane and cytosolic PGES) 4 h after 35 Gy single dose irradiation to the brains of C3HeN mice. We also evaluated the effects of specific COX inhibitors on PGE 2 production and PGES expression. Results: As expected, COX-2 expression increased after radiation exposure. Brain irradiation also increased tissue protein levels for both PGES isoforms. Specific COX-2 inhibition with NS398 lowered brain PGE 2 levels by about 60%. Surprisingly, COX-1 inhibition with SC560 completely prevented the elevation of PGE 2 seen after irradiation. Interestingly, NS398 reduced the membrane-associated PGES isoform, whereas SC560 treatment lowered cytosolic isoform levels below those seen in unirradiated controls. Conclusions: Taken together, these data indicate that both cyclooxygenases contribute to PGE 2 production in irradiated brain and reveal dependence of PGES isoforms expression on specific cyclooxygenase activities

  12. Prostaglandin E2 Receptor Expression by Osteoblasts is Modulated by Implant Surface Roughness and Prostaglandin E2

    National Research Council Canada - National Science Library

    Campbell, MaCasey M

    2006-01-01

    .... Relatively little is known about the cellular receptors for prostaglandins, EP receptors, especially with regard to osteoblast response to implant surface roughness and early events preceding osseointegration...

  13. 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

  14. Does prostaglandin-E1 modulate D-galactosamine induced cell ...

    African Journals Online (AJOL)

    In vitro and in vivo studies have shown that D-galactosamine (DGA) induces hepatocyte damage. Objective: The present study aims to evaluate the protective effect of prostaglandin E1 (PGE1) on DGA-induced apoptosis, necrosis and oxidative stress in primary culture of human hepatocytes. Methods: Normal human ...

  15. Interferon alpha inhibits viral replication of a live-attenuated porcine reproductive and respiratory syndrome virus vaccine preventing development of an adaptive immune response in swine

    Science.gov (United States)

    Type I interferons, such as interferon alpha (IFNa), contribute to innate antiviral immunity by promoting production of antiviral mediators and are also involved in promoting an adaptive immune response. Porcine reproductive and respiratory syndrome virus (PRRSV) is one of the most devastating and c...

  16. Activation of p53 pathway by Nutlin-3a inhibits the expression of the therapeutic target alpha 5 integrin in colon cancer cells

    Czech Academy of Sciences Publication Activity Database

    Janoušková, Hana; Ray, A.M.; Noulet, F.; Lelong-Rebel, I.; Choulier, L.; Schaffner, F.; Lehmann, M.; Martin, S.; Teisinger, Jan; Dontenwill, M.

    2013-01-01

    Roč. 336, č. 2 (2013), s. 307-318 ISSN 0304-3835 Institutional support: RVO:67985823 Keywords : colon cancer * integrin alpha 5 beta 1 * p53 * Nutlin-3a Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 5.016, year: 2013

  17. 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

  18. 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-in...

  19. Prostaglandin E1 in hand angiography

    Energy Technology Data Exchange (ETDEWEB)

    Levy, J.M.; Joseph, R.B.; Bodell, L.S.; Nykamp, P.W.; Hessel, S.J.

    1983-11-01

    Prostaglandin E1 (PG1) is a rapid, potent vasodilator which, when infused into the arterial system in low doses by bolus injection, has no significant systemic effects and has a relatively long duration of action. Sixty-three hand angiograms were done on 55 patients, comparing PGE1 to tolazoline and to angiograms done with no vasodilation. There was no significant difference between PGE1 and tolazoline in digital artery opacification; however, venous opacification was very significantly better with PGE1. PGE1 should be a drug of choice in hand angiography.

  20. Prostaglandin E1 in hand angiography

    International Nuclear Information System (INIS)

    Levy, J.M.; Joseph, R.B.; Bodell, L.S.; Nykamp, P.W.; Hessel, S.J.

    1983-01-01

    Prostaglandin E1 (PG1) is a rapid, potent vasodilator which, when infused into the arterial system in low doses by bolus injection, has no significant systemic effects and has a relatively long duration of action. Sixty-three hand angiograms were done on 55 patients, comparing PGE1 to tolazoline and to angiograms done with no vasodilation. There was no significant difference between PGE1 and tolazoline in digital artery opacification; however, venous opacification was very significantly better with PGE1. PGE1 should be a drug of choice in hand angiography

  1. Cervical ripening with prostaglandin gel and hygroscopic dilators.

    Science.gov (United States)

    Hibbard, J U; Shashoua, A; Adamczyk, C; Ismail, M

    1998-01-01

    OBJECTIVE: To study the effectiveness and morbidity of adding hygroscopic cervical dilators to prostaglandin gel for cervical ripening and labor induction. STUDY DESIGN: Patients of at least 34 weeks' gestation with a medical indication for induction of labor and with a modified Bishop score of 5 or less were randomized to receive either prostaglandin gel or prostaglandin gel with hygroscopic cervical dilators. Primary outcomes were time to delivery, change in cervical score, and infection. Secondary outcomes included cesarean delivery rate and deliveries before 24 hours of induction. Continuous variables were analyzed by Wilcoxon sum rank test and categorical data by chi-square or Fisher exact test, with P intracervical prostaglandin alone and 23 patients received intracervical prostaglandin plus hygroscopic dilators. No demographic differences were noted between the groups. After six hours of ripening, the combined group achieved a greater change in Bishop score (3.6 vs. 2.1, P = 0.007) and tended to have a shorter induction time (21.7 vs. 26.4 hours, P = 0.085). The combined therapy group had a higher infection rate than the prostaglandin-only group (59% vs. 12%, P = 0.003). CONCLUSION: Combining cervical dilators with prostaglandin gel provides more effective cervical ripening and a more rapid induction to delivery interval than prostaglandin alone but with a significant and prohibitive rate of infection. PMID:9678143

  2. Prostaglandin H synthase immunoreactivity in human gut. An immunohistochemical study

    DEFF Research Database (Denmark)

    Mikkelsen, H B; Rumessen, J J; Qvortrup, K

    1991-01-01

    Prostaglandins exhibit a variety of actions on intestinal smooth muscle depending upon the type, dose and muscle layer studied. As the cellular origin of prostaglandin H (PGH) synthase has not been established with certainty in the human gut wall, we studied the localization of PGH synthase...

  3. 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

  4. 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

  5. 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

  6. Prostaglandin E2 regulates hematopoietic stem cell

    International Nuclear Information System (INIS)

    Wang Yingying; Zhou Daohong; Meng Aimin

    2013-01-01

    Prostaglandin E2 (PGE2) is a bioactive lipid molecule produced by cyclooxygenase (COX), which plays an important role on hematopoiesis. While it can block differentiation of myeloid progenitors but enhance proliferation of erythroid progenitors. Recent research found that PGE2 have the effects on hematopoietic stem cell (HSC) function and these effects were independent from effects on progenitor cells. Exposure of HSC cells to PGE2 in vitro can increase homing efficiency of HSC to the murine bone marrow compartment and decrease HSC apoptosis, meanwhile increase long-term stem cell engraftment. In-vivo treatment with PGE2 expands short-term HSC and engraftment in murine bone marrow but not long-term HSC.In addition, PGE2 increases HSC survival after radiation injury and enhance hematopoietic recovery, resulting maintains hematopoietic homeostasis. PGE2 regulates HSC homeostasis by reactive oxygen species and Wnt pathway. Clinical beneficial of 16, 16-dimethyl-prostaglandin E2 treatment to enhance engraftment of umbilical cord blood suggest important improvements to therapeutic strategies. (authors)

  7. Prostaglandins and their precursors can modify genetic damage-induced by gamma-radiation and benzo(a)pyrene

    International Nuclear Information System (INIS)

    Das, U.N.; Ramadevi, G.; Rao, K.P.; Rao, M.S.

    1985-01-01

    Experiments were performed to study the effect of various prostaglandins (PGs) and their precursors, gamma-linolenic acid (GLA) and arachidonic acid (AA) on gamma-radiation and benzo (a) pyrene (BP)-induced genetic damage to the bone marrow cells of mice, using the sensitive micronucleus (MN) test. Thromboxane B2 prostaglandin E1 and GLA completely prevented BP-induced and reduced to a great degree radiation-induced genetic damage, where as PGE2, PGF2 alpha and AA were without any effect. Since GLA and AA are widely distributed in the cell membranes, and as PGs can be formed virtually in response to any type of stimulus, it is likely that GLA and PGE1 may function as endogenous anti-mutagenic chemicals

  8. 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

  9. Phytosterols decrease prostaglandin release in cultured P388D1/MAB macrophages.

    Science.gov (United States)

    Awad, Atif B; Toczek, Jeffrey; Fink, Carol S

    2004-06-01

    Cardiovascular disease (CVD) remains the leading cause of death in Western societies. Atherosclerosis is a major cardiovascular related disorder that is responsible for 50% of all mortality in the United States. Several epidemiological studies suggest that consumption of a plant-based diet is associated with a decreased incidence of cardiovascular abnormalities. Phytosterols, especially beta-sitosterol, are plant sterols that have been shown to exert protective effects against cardiovascular diseases as well as many types of cancer. Monocyte/macrophage cells are involved with the inflammatory process. Accumulation of these cells in arteries is one of the initial events leading to atherosclerosis. Macrophages are capable of supplying the atherosclerotic vessel with substantial amounts of prostaglandins. Prostaglandins have been shown by numerous studies to play a key role in the atherosclerosis process. They can affect platelet aggregation, vasodilation or constriction of blood vessels, and the adherence of monocytes to the vessel walls. The purpose of this study was to examine the effect of phytosterols on the release of PGE(2) and PGI(2) from lipopolysaccharide (LPS)-stimulated P388D(1)/MAB macrophage cells. P388D(1)/MAB cells were supplemented with 16 microM cholesterol, beta-sitosterol or campesterol using cyclodextrin as a vehicle. Phytosterol supplementation led to a significant decrease in cellular growth at various time points throughout a 7-day treatment period, especially after 3 days of treatment. Macrophages incorporated the supplemented phytosterols into their membranes which accounted for 26% of total membrane sterols. Cholesterol supplementation at 16 microM however, had no effect on membrane sterols. Supplementation with 16 microM concentration of beta-sitosterol or campesterol resulted in a significant inhibition of PGE(2) and PGI(2) release from macrophage cells as compared to the vehicle control. Of the two phytosterols, beta

  10. 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.

    2014-01-01

    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. PMID:24284900

  11. Kinetics of prostaglandin E2 and thromboxane A2 synthesis and suppression of PHA-stimulated peripheral blood mononuclear leucocytes.

    Science.gov (United States)

    Awara, W; Hillier, K; Jones, D

    1986-12-01

    The immunomodulatory effects of thromboxane A2 and prostaglandin E2 on peripheral blood mononuclear leucocytes stimulated with PHA in vitro, and the relationship of this to the time-course of their synthesis in culture, were investigated using prostaglandin E2, a thromboxane A2 synthesis inhibitor (UK37248), a thromboxane A2 mimic (U46619) and a thromboxane A2 receptor blocker (EP045). The inhibitory effect of prostaglandin E2 on PHA-induced human peripheral blood mononuclear leucocyte proliferation diminishes if the addition of PGE2 is delayed. If added 4 hr after a maximum concentration of PHA (5 micrograms/ml), the effect of PGE2 was reduced by 60%. If a submaximal concentration of PHA (1 microgram/ml) was used, the effect of PGE2 was not reduced if added 4 hr later but fell by about 60% after 16 hr. UK37248 moderately inhibited PHA-induced activation while substantially inhibiting thromboxane A2 synthesis and simultaneously enhancing PGE2 synthesis. The enhanced accumulation of PGE2 occurs while sensitivity to PGE2 is dropping. U46619, exogenously applied as a thromboxane A2 mimic, inhibited PHA-induced activation at concentrations that did not significantly alter PGE2 synthesis. EP045, which may modulate the effects of endogenous thromboxane A2 by blocking receptors, did not alter PHA-induced activation. We conclude that thromboxane A2 may have a role in inhibiting PHA-induced activation on the basis of the effect of U46619. However, this study highlights difficulties in utilizing prostaglandin and thromboxane receptor and synthesis inhibitors to examine their endogenous role in the modulation of mitogen-induced activation in vitro. If sensitivity to the purported endogenous substance is limited to the early stages of culture and if only low levels are synthesized at this early stage, then blocking drugs would have little effect.

  12. 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.

  13. The inhibitory actions of prostaglandins on respiratory smooth muscle

    Science.gov (United States)

    Main, I. H. M.

    1964-01-01

    Prostaglandin E1, in concentrations as low as 1 ng/ml., relaxed isolated tracheal muscle from cat, monkey, rabbit, guinea-pig and ferret. Tracheal muscle from the cat, monkey and rabbit did not exhibit inherent tone and the effect of prostaglandin E1 on these preparations was seen only after a sustained contraction had been produced by a previous dose of acetylcholine or of another agonist. Prostaglandins E2, E3 and F1α also relaxed isolated cat tracheal muscle which had been stimulated by acetylcholine: their activities relative to that of prostaglandin E1 were, respectively, 1.0, 0.2 and 0.002. In the anaesthetized cat prostaglandin E1 increased lung “resistance to inflation” (presumably comparable to bronchial resistance) and the heart rate. In the anaesthetized rabbit and guinea-pig, prostaglandin E1 antagonized the rise in resistance to inflation of the lungs obtained after vagal stimulation or after the intravenous injection of histamine; it sometimes lowered the resistance to inflation in these species. The possibility that prostaglandin may have a local physiological role in the control of bronchial smooth muscle tone is discussed. ImagesFig. 5Fig. 7 PMID:14211681

  14. 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

    (controls) and with prior N(G)-nitro-L-arginine methyl ester (L-NAME) infusion (4 mg/kg, intravenously). Samples from the interstitial fluid were obtained at rest, during exercise and after exercise with the microdialysis technique. Interstitial adenosine in controls increased (p0.05) to controls. The 6......-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......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...

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

    OpenAIRE

    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...

  16. Inhibition of tumor necrosis factor alpha-stimulated monocyte adhesion to human aortic endothelial cells by AMP-activated protein kinase.

    Science.gov (United States)

    Ewart, Marie-Ann; Kohlhaas, Christine F; Salt, Ian P

    2008-12-01

    Proatherosclerotic adhesion of leukocytes to the endothelium is attenuated by NO. As AMP-activated protein kinase (AMPK) regulates endothelial NO synthesis, we investigated the modulation of adhesion to cultured human aortic endothelial cells (HAECs) by AMPK. HAECs incubated with the AMPK activator, AICAR, or expressing constitutively active AMPK demonstrated reduced TNFalpha-stimulated adhesion of promonocytic U-937 cells. Rapid inhibition of TNFalpha-stimulated U-937 cell adhesion by AICAR was NO-dependent, associated with unaltered cell surface adhesion molecule expression, and reduced MCP-1 secretion by HAECs. In contrast, inhibition of TNFalpha-stimulated U-937 cell adhesion by prolonged AMPK activation was NO-independent and associated with reduced cell surface adhesion molecule expression. AMPK activation in HAECs inhibits TNFalpha-stimulated leukocyte adhesion by a rapid NO-dependent mechanism associated with reduced MCP-1 secretion and a late NO-independent mechanism whereby adhesion molecule expression, in particular E-selectin, is suppressed.

  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. 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

    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...

  19. A novel role for 3, 4-dichloropropionanilide (DCPA in the inhibition of prostate cancer cell migration, proliferation, and hypoxia-inducible factor 1alpha expression

    Directory of Open Access Journals (Sweden)

    Schafer Rosana

    2006-08-01

    Full Text Available Abstract Background The amide class compound, 3, 4-dichloropropionanilide (DCPA is known to affect multiple signaling pathways in lymphocyte and macrophage including the inhibition of NF-κB ability. However, little is known about the effect of DCPA in cancer cells. Hypoxia-inducible factor 1 (HIF-1 regulates the expression of many genes including vascular endothelial growth factor (VEGF, heme oxygenase 1, inducible nitric oxide synthase, aldolase, enolase, and lactate dehydrogenase A. HIF-1 expression is associated with tumorigenesis and angiogenesis. Methods We used Transwell assay to study cell migration, and used immunoblotting to study specific protein expression in the cells. Results In this report, we demonstrate that DCPA inhibited the migration and proliferation of DU145 and PC-3 prostate cancer cells induced by serum, insulin, and insulin-like growth factor I (IGF-I. We found that DCPA inhibited HIF-1 expression in a subunit-specific manner in these cancer cell lines induced by serum and growth factors, and decreased HIF-1α expression by affecting its protein stability. Conclusion DCPA can inhibit prostate cancer cell migration, proliferation, and HIF-1α expression, suggesting that DCPA could be potentially used for therapeutic purpose for prostate cancer in the future.

  20. Evaluation of plasma and urinary levels of 6-keto-prostaglandin F1a as a marker for asymptomatic myxomatous mitral valve disease in dogs

    DEFF Research Database (Denmark)

    Rasmussen, Caroline Elisabeth; Sundqvist, Anna Vilhelmina; Kjempff, Christina Tirsdal

    2010-01-01

    Endothelial dysfunction might be involved in the pathogenesis of myxomatous mitral valve disease (MMVD). The aims of this study were (1) to validate an enzyme immunoassay (EIA) for canine 6-keto-prostaglandin (PG)F(1alpha) (prostacyclin metabolite and marker for endothelial function) and (2......) to compare plasma and urinary 6-keto-PGF(1alpha) in dogs with asymptomatic MMVD. The study included two breeds predisposed to MMVD and two control groups (Cairn terriers and dogs of different breeds). Echocardiography was used to estimate the severity of MMVD. The intra- and inter-assay coefficients...... of variation were between 3.1% and 24.5% in the assay range. No echocardiographic parameter was correlated with plasma or urinary 6-keto-PGF(1alpha) (P>0.05), but all control dogs had lower urinary 6-keto-PGF(1alpha) (Pketo-PGF(1alpha) (P

  1. [Effect of prostaglandin E1 combined with Xuebijing injection on transforming growth factor-β₁ in rats with pulmonary interstitial fibrosis].

    Science.gov (United States)

    Zhang, Wan-xiang; Li, Zhi-jun

    2012-12-01

    To investigate the effect of prostaglandins E1 combined with Xuebijing injection on the expression of transforming growth factor-β₁ (TGF-β₁) and tumor necrosis factor-α (TNF-α) in rats with acute pulmonary interstitial fibrosis. A rat model of pulmonary interstitial fibrosis was established by intratracheal injection of bleomycin (1 ml/kg). One hundred and eight Wistar rats were randomly divided into six groups with 18 in each group, which were normal control group, model group, hormone (methylprednisolone) treatment group, Xuebijing treatment group, prostaglandin E1 treatment group and combination treatment group (prostaglandin E1 and Xuebijing injection). Except for those in the normal control group, the rats in each group were sacrificed on the 7th, 14th and 28th day after treatment. The TGF-β₁ expression in lung tissue was measured by immunohistochemical staining. The TNF-α concentration in bronchoalveolar lavage fluid (BALF) of rat model was determined by enzyme-linked immunosorbent assay. The combination treatment group showed significantly more macrophages with TGF-β₁ expression in lung tissue at each time point, as compared with the model group, Xuebijing treatment group, methylprednisolone treatment group and prostaglandin E1 treatment group (P prostaglandin E1 treatment group (P prostaglandin E1 treatment group and combination treatment group were significantly lower than that in the model group (P Prostaglandin E1 combined with Xuebijing injection may significantly inhibit TGF-β₁ expression in the lung tissue of rats with acute pulmonary interstitial fibrosis, which reduces alveolar inflammatory response.

  2. Tussilagone Inhibits the Inflammatory Response and Improves Survival in CLP-Induced Septic Mice.

    Science.gov (United States)

    Kim, Yun Kyu; Yeo, Myeong Gu; Oh, Bo Kang; Kim, Ha Yeong; Yang, Hun Ji; Cho, Seung-Sik; Gil, Minchan; Lee, Kyung Jin

    2017-12-18

    Tussilagone, extracted from Tussilago farfara is an oriental medicine used for asthma and bronchitis. We investigated its mechanism of action, its inhibitory effects on lipopolysaccharide-induced inflammation in macrophages, and its impact on viability in a cecal ligation and puncture (CLP)-induced mouse model of sepsis. Tussilagone suppressed the expression of the inflammatory mediators, nitric oxide and prostaglandin E2, and the inflammatory cytokines, tumor necrosis factor-alpha (TNF-α) and high-mobility group box 1 (HMGB1), in lipopolysaccharide-stimulated RAW 264.7 cells and peritoneal macrophages. Tussilagone also reduced the activation of the mitogen-activated protein kinases and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) involved in the activation of various inflammatory mediators in activated macrophages. Moreover, tussilagone administration (1 mg/kg and 10 mg/kg) produced decreased mortality and lung injury in CLP-activated septic mice. Augmented expression of cyclooxygenase (COX)-2 and TNF-α in pulmonary alveolar macrophages of septic mice were attenuated by tussilagone administration. Tussilagone also suppressed the induction of nitric oxide, prostaglandin E2, TNF-α and HMGB1 in the serum of the septic mice. Overall, tussilagone exhibited protective effects against inflammation and polymicrobial sepsis by suppressing inflammatory mediators possibly via the inhibition of NF-κB activation and the MAP kinase pathway. These results suggest the possible use of tussilagone for developing novel therapeutic modalities for sepsis and other inflammatory diseases.

  3. 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

  4. Ageratum conyzoides L. inhibits 5-alpha-reductase gene expression in human prostate cells and reduces symptoms of benign prostatic hypertrophy in otherwise healthy men in a double blind randomized placebo controlled clinical study.

    Science.gov (United States)

    Detering, Matthew; Steels, Elizabeth; Koyyalamudi, Sundar Rao; Allifranchini, Elena; Bocchietto, Elena; Vitetta, Luis

    2017-11-01

    A double-blind, randomized, placebo-controlled clinical trial assessed the efficacy and safety of Ageratum conyzoides in treating benign prostatic hypertrophy (BPH). In this study, 109 men with medically diagnosed BPH, aged 41-76 years, were administered the investigational product, A. conyzoides extract at a dose of 250 mg/d or placebo, q.d. for 12 weeks. The primary outcome measures were the International Prostate Symptom Score (IPSS), daily urinary frequency and safety evaluations. The secondary outcome measures were testosterone, dihydrotestosterone, oestradiol, sex hormone binding globulin (SHBG), Dehydroepiandrosterone sulfate (DHEA-S) and cortisol levels, and prostate specific antigen (PSA), lipids, blood glucose, the Aging Male's Symptom (AMS) Score and sexual function assessed by Derogatis Interview for Sexual Functioning-Self Report (DISF-SR). The effect of A. conyzoides L extract on gene expression of 5-alpha-reductase in human prostate cells was also investigated to elucidate a potential mechanism of action. The clinical study, showed a significant reduction in total IPSS score (p prostate epithelial cells. The overall results indicate that A. conyzoides may be an effective treatment for reducing symptoms of BPH in healthy men, in part, through inhibition of 5-alpha-reductase enzyme activity. © 2017 BioFactors, 43(6):789-800, 2017. © 2017 International Union of Biochemistry and Molecular Biology.

  5. Prostaglandins versus oxytocin for prelabour rupture of membranes at term.

    Science.gov (United States)

    Tan, B P; Hannah, M E

    2000-01-01

    The conventional method of induction of labour is with intravenous oxytocin. More recently, induction with prostaglandins, followed by an infusion of oxytocin if necessary, has been used. The objective of this review was to assess the effects of induction of labour with prostaglandins versus oxytocin for prelabour rupture of membranes at term. We searched the Cochrane Pregnancy and Childbirth Group trials register. Randomised and quasi-randomised trials of early stimulation of uterine contractions with prostaglandins (with or without oxytocin) versus with oxytocin alone (not combined with prostaglandins) in women with spontaneous rupture of membranes at term (37 weeks or more gestation). Two reviewers assessed trial quality and extracted data. Eight trials were included. Based on three trials, prostaglandins compared to oxytocin were associated with increased chorioamnionitis (odds ratio of 1.51, 95% confidence interval 1.07 to 2.12) and neonatal infections (odds ratio 1.63, 95% confidence interval 1.00 to 2.66). Based on four trials, prostaglandins were associated with a decrease in epidural analgesia (odds ratio of 0.86, 95% confidence interval 0.73 to 1.00) and internal fetal heart rate monitoring (based on one trial). Caesarean section, endometritis and perinatal mortality were not significantly different between the groups. Women with prelabour rupture of membranes at term having their labour induced with prostaglandins appear to have a lower risk of epidural analgesia and fetal heart rate monitoring. However there appears to be an increased risk of chorioamnionitis and neonatal infections after prostaglandin induction compared to oxytocin.

  6. Interaction between prostaglandins and gonadotrophins in the rabbit ovary

    Science.gov (United States)

    Bedwani, J. R.; Horton, E. W.

    1971-01-01

    1. It has been suggested that prostaglandins function as feedback modulators of hormonal actions which are mediated by adenosine 3′,5′-monophosphate (cyclic AMP). This hypothesis has been tested on the rabbit ovary, whose steroidogenic response to luteinizing hormone (LH) is mediated by the cyclic nucleotide. 2. Prostaglandin E1 (1-100 μg/ml) reduced the production of progesterone by rabbit ovaries incubated in the presence of a submaximal concentration of LH, but had no effect on the formation of this steroid when exogenous cyclic AMP was used as the stimulating agent. The prostaglandin was without effect on the formation of 20α-hydroxypregn-4-en-3-one in the presence of either LH or cyclic AMP. 3. Prostaglandin E2 (1 μg/ml) was without effect on ovarian steroidogenesis in the presence of LH. 4. There was no evidence that exogenous prostaglandin E1 was inactivated during incubation with rabbit ovaries in the presence of LH. 5. Prostaglandin E-like compounds were detected in homogenates of incubated rabbit ovaries. However, concentrations of LH sufficient to stimulate steroidogenesis did not stimulate the synthesis of these compounds by the ovary in vitro, nor their release from the ovary in vivo. 6. It is concluded that the prostaglandin-like compounds detected in the ovary are unlikely to play a role in the regulation of steroidogenesis. The results of this investigation do not support the hypothesis that prostaglandins function as general modulators of hormonal actions which are mediated by cyclic AMP. PMID:4339885

  7. Alpha-Mangostin suppresses interleukin-1β-induced apoptosis in rat chondrocytes by inhibiting the NF-κB signaling pathway and delays the progression of osteoarthritis in a rat model.

    Science.gov (United States)

    Pan, Tianlong; Chen, Rong; Wu, Dengying; Cai, Ningyu; Shi, Xuchao; Li, Bin; Pan, Jun

    2017-11-01

    Osteoarthritis (OA) is a chronic degenerative joint disease that is characterized by progressive joint dysfunction and pain. Apoptosis and catabolism in chondrocytes play critical roles in the development of OA. Alpha-Mangostin (α-MG), one of the main components of the mangosteen, has been reported to have anti-apoptotic, anti-inflammatory and antioxidant effects. We investigated the therapeutic effects of α-MG on OA through experiments on rat chondrocytes in vitro and in a rat model of OA induced by destabilization of the medial meniscus (DMM). In vitro, we provided experimental evidence that α-MG inhibits the expression of MMP-13 and ADAMTs-5, and promotes the expression of SOX-9 in rat chondrocytes stimulated with interleukin-1β (IL-1β). In addition, we also found that α-MG can inhibit the expression of pro-apoptotic proteins such as Bax, Cyto-c, and C-caspase3, and increase the expression of the anti-apoptotic protein Bcl-2. These changes may be related to an α-MG induced inhibition of the IL-1β-induced activation of the NF-kB signaling pathway. In vivo, we also found that α-MG can limit the development of OA in rat models. The above results show that α-MG has a potential therapeutic effect on OA, and that this effect may be achieved by inhibiting the mitochondrial apoptosis of chondrocytes induced by an activation of the NF-kB pathway. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. 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.

  9. In vitro evaluation and determination of responsible fraction of coffee beans and dried sugar beet leaves for alpha-glucosidase inhibition.

    OpenAIRE

    K. Singh; A. Kafka; B-H Kang; R. Goundra; Y-I Kwon; E. Apostolidis

    2013-01-01

    Summary. Recent studies have identified that hydrophobic phenolic phytochemicals and hydrophilic Amadori compounds have potential for type 2 diabetes management via inhibition of carbohydrate hydrolysis enzymes. Here, we determined the phenolic content, α-glucosidase inhibitory activity, and pancreatic α-amylase inhibitory activity of water extracts of roasted and unroasted coffee beans and dried sugar beet leaves. Sugar beet leaves appeared to have the lowest total phenolic content while unr...

  10. Oral midodrine for prostaglandin e1 induced priapism in spinal cord injured patients.

    Science.gov (United States)

    Soler, Jean-Marc; Previnaire, Jean-Gabriel; Mieusset, Roger; Plante, Pierre

    2009-09-01

    We evaluated midodrine as oral treatment for pharmacologically induced priapism in spinal cord injured patients. From 2004 to 2007 we treated 354 spinal cord injured patients with intracavernous injection of prostaglandin E1 to induce erection. Prolonged erection or priapism occurred in 14 cases (1.3% of intracavernous injections). High blood pressure and bradycardia (autonomic dysreflexia) were noted in 2 tetraplegic cases. Except in 2 patients oral midodrine was used as the only therapeutic approach to this event because of its alpha stimulant properties. All patients returned to the flaccid penile state within 30 to 45 minutes after midodrine administration. Oral midodrine was well tolerated with few side effects and without increasing the incidence of autonomic dysreflexia. At 6 months complete erection could be again induced by intracavernous injection in all treated patients. Midodrine administered orally is a simple and efficient treatment for the priapism induced by intracavernous injection of prostaglandin E1. It could be the first line therapeutic approach before more aggressive procedures.

  11. Inhibition of c-Jun-N-terminal kinase increases cardiac peroxisome proliferator-activated receptor alpha expression and fatty acid oxidation and prevents lipopolysaccharide-induced heart dysfunction.

    Science.gov (United States)

    Drosatos, Konstantinos; Drosatos-Tampakaki, Zoi; Khan, Raffay; Homma, Shunichi; Schulze, P Christian; Zannis, Vassilis I; Goldberg, Ira J

    2011-10-21

    Septic shock results from bacterial infection and is associated with multi-organ failure, high mortality, and cardiac dysfunction. Sepsis causes both myocardial inflammation and energy depletion. We hypothesized that reduced cardiac energy production is a primary cause of ventricular dysfunction in sepsis. The JNK pathway is activated in sepsis and has also been implicated in impaired fatty acid oxidation in several tissues. Therefore, we tested whether JNK activation inhibits cardiac fatty acid oxidation and whether blocking JNK would restore fatty acid oxidation during LPS treatment. LPS treatment of C57BL/6 mice and adenovirus-mediated activation of the JNK pathway in cardiomyocytes inhibited peroxisome proliferator-activated receptor α expression and fatty acid oxidation. Surprisingly, none of the adaptive responses that have been described in other types of heart failure, such as increased glucose utilization, reduced αMHC:βMHC ratio or induction of certain microRNAs, occurred in LPS-treated mice. Treatment of C57BL/6 mice with a general JNK inhibitor (SP600125) increased fatty acid oxidation in mice and a cardiomyocyte-derived cell line. JNK inhibition also prevented LPS-mediated reduction in fatty acid oxidation and cardiac dysfunction. Inflammation was not alleviated in LPS-treated mice that received the JNK inhibitor. We conclude that activation of JNK signaling reduces fatty acid oxidation and prevents the peroxisome proliferator-activated receptor α down-regulation that occurs with LPS.

  12. Intracervical Foley catheter balloon vs. prostaglandin in preinduction cervical ripening.

    Science.gov (United States)

    Niromanesh, S; Mosavi-Jarrahi, A; Samkhaniani, F

    2003-04-01

    The aim of this study is to compare the effectiveness of the intracervical Foley balloon catheter and 3 mg prostaglandin E(2) tablet(s) in preinduction cervical ripening. Ninety women referred to the maternity clinic for induction of labor with a Bishop score of less than or equal to 5 were randomized to receive an intracervical Foley catheter or prostaglandin E(2) tablets. The primary measured outcome was ripening of the cervix as measured with the Bishop score. There were no differences in mean Bishop scores between the prostaglandin and the Foley catheter groups. Bishop scores (mean+/-S.D.) after ripening were 6.6+/-0.80 and 6.7+/-0.86 for the Foley catheter and prostaglandin groups, respectively (P=0.54). The Foley catheter group showed a statistically shorter time to ripening compared with the prostaglandin group (3.4+/-2.1 and 6.5+/-3.2 h, respectively (P=0.001). There was no statistically significant difference in induction time (4.8+/-1.8 h and 5.3+/-2.4 h, respectively (P=0.36). There are no differences in preinduction cervical ripening efficacy between prostaglandin E(2) and the Foley catheter, but the Foley catheter has the advantage of ripening an unfavorable cervix in a shorter time.

  13. Prostaglandins in Cancer Cell Adhesion, Migration, and Invasion

    Directory of Open Access Journals (Sweden)

    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.

  14. Activator protein 2alpha mediates parathyroid TGF-alpha self-induction in secondary hyperparathyroidism.

    Science.gov (United States)

    Arcidiacono, Maria Vittoria; Cozzolino, Mario; Spiegel, Noah; Tokumoto, Masanori; Yang, Jing; Lu, Yan; Sato, Tetsuhiko; Lomonte, Carlo; Basile, Carlo; Slatopolsky, Eduardo; Dusso, Adriana S

    2008-10-01

    In secondary hyperparathyroidism, enhanced expression of TGF-alpha in the parathyroid leads to its own upregulation, generating a feed-forward loop for TGF-alpha activation of its receptor, EGFR receptor (EGFR), which promotes parathyroid hyperplasia. These studies examined the role of activator protein 2alpha (AP2), an inducer of TGF-alpha gene transcription, in the upregulation of parathyroid TGF-alpha in secondary hyperparathyroidism. In rat and human secondary hyperparathyroidism, parathyroid AP2 expression strongly correlated with TGF-alpha levels and with the rate of parathyroid growth, as expected. Furthermore, the increases in rat parathyroid content of AP2 and its binding to a consensus AP2 DNA sequence preceded the increase in TGF-alpha induced by high dietary phosphate. More significant, in A431 cells, which provide a model of enhanced TGF-alpha and TGF-alpha self-induction, mutating the core AP2 site of the human TGF-alpha promoter markedly impaired promoter activity induced by endogenous or exogenous TGF-alpha. Important for therapy, in five-sixths nephrectomized rats fed high-phosphate diets, inhibition of parathyroid TGF-alpha self-induction using erlotinib, a highly specific inhibitor of TGF-alpha/EGFR-driven signals, reduced AP2 expression dosage dependently. This suggests that the increases in parathyroid AP2 occur downstream of EGFR activation by TGF-alpha and are required for TGF-alpha self-induction. Indeed, in A431 cells, erlotinib inhibition of TGF-alpha self-induction caused parallel reductions in AP2 expression and nuclear localization, as well as TGF-alpha mRNA and protein levels. In summary, increased AP2 expression and transcriptional activity at the TGF-alpha promoter determine the severity of the hyperplasia driven by parathyroid TGF-alpha self-upregulation in secondary hyperparathyroidism.

  15. Aromatase inhibition by 4 beta,5 beta-epoxides of 16 alpha-hydroxyandrostenedione and its 19-oxygenated analogs, potential precursors of estriol production in the feto-placental unit.

    Science.gov (United States)

    Numazawa, Mitsuteru; Yoshimura, Akiko; Watari, Yoko; Matsuzaki, Hisao

    2002-12-01

    To gain insight into the nature of the substrate binding site and the catalytic function of aromatase, we studied the inhibition of androstenedione aromatization by 4beta,5beta-epoxy-16alpha-hydroxyandrostenedione (4) and its 19-hydroxy and 19-oxo derivatives, 5 and 6, as well as the biochemical aromatization of these steroids in human placental microsomes. The 19-methyl and 19-oxo compounds, 4 and 6, were weak competitive inhibitors of aromatase, with apparent K(i) values of 246 microM and 270 microM, respectively, whereas the 19-hydroxy compound 5 inhibited aromatase in a non-competitive manner with the K(i) of 135 microM. The 19-methyl compound 4 inactivated aromatase in a time-dependent manner with k(inact) of 0.213 min(-1) in the presence of NADPH in air, but the other two did not cause it. The conversion of the three epoxides into estrogen, as well as 19-oxygenation of 19-methyl steroid 4 with human placental microsomes in the presence of NADPH in air, were not detected by gas chromatography-mass spectrometry. The present results are consistent with the two binding sites theory in the active site of aromatase.

  16. Upregulation of heat shock protein 70 and the differential protein expression induced by tumor necrosis factor-alpha enhances migration and inhibits apoptosis of hepatocellular carcinoma cell HepG2.

    Science.gov (United States)

    Huang, Bee-Piao; Lin, Chun-Shiang; Wang, Chau-Jong; Kao, Shao-Hsuan

    2017-01-01

    Tumor necrosis factor alpha (TNFα) plays diverse roles in liver damage and hepatocarcinogenesis with its multipotent bioactivity. However, the influence of TNFα on protein expression of hepatocellular carcinoma (HCC) is incompletely understood. Therefore, we aimed to investigate the differential protein expression of HCC in response to TNFα stimulus. We observed that HepG2 cell revealed a higher resistance to TNFα-induced apoptosis as compared to the non-tumorigenic hepatocyte THLE-2. By using a label-free quantitative proteomic analysis, we found that 520 proteins were differentially expressed in the HepG2 cells exposed to TNFα, including 211 up-regulated and 309 down-regulated proteins. We further confirmed several proteins with significant expression change (TNFα/control ratio>2.0 or expressed proteins using Gene ontology and KEGG annotations, and the results implicated that TNFα might regulate ribosome, spliceosome, antigen processing and presentation, and energy metabolism in HepG2 cells. Moreover, we demonstrated that upregulation of heat shock protein 70 (HSP70) was involved in both the promoted migration and the inhibited apoptosis of HepG2 cells in response to TNFα. Collectively, these findings indicate that TNFα alters protein expression such as HSP70, which triggering specific molecular processes and signaling cascades that promote migration and inhibit apoptosis of HepG2 cells.

  17. Inhibition of Toll-like receptor 2-mediated interleukin-8 production in Cystic Fibrosis airway epithelial cells via the alpha7-nicotinic acetylcholine receptor.

    LENUS (Irish Health Repository)

    Greene, Catherine M

    2010-01-01

    Cystic Fibrosis (CF) is an inherited disorder characterised by chronic inflammation of the airways. The lung manifestations of CF include colonization with Pseudomonas aeruginosa and Staphylococcus aureus leading to neutrophil-dominated airway inflammation and tissue damage. Inflammation in the CF lung is initiated by microbial components which activate the innate immune response via Toll-like receptors (TLRs), increasing airway epithelial cell production of proinflammatory mediators such as the neutrophil chemokine interleukin-8 (IL-8). Thus modulation of TLR function represents a therapeutic approach for CF. Nicotine is a naturally occurring plant alkaloid. Although it is negatively associated with cigarette smoking and cardiovascular damage, nicotine also has anti-inflammatory properties. Here we investigate the inhibitory capacity of nicotine against TLR2- and TLR4-induced IL-8 production by CFTE29o- airway epithelial cells, determine the role of alpha7-nAChR (nicotinic acetylcholine receptor) in these events, and provide data to support the potential use of safe nicotine analogues as anti-inflammatories for CF.

  18. Buffett's Alpha

    DEFF Research Database (Denmark)

    Frazzini, Andrea; Kabiller, David; Heje Pedersen, Lasse

    Berkshire Hathaway has realized a Sharpe ratio of 0.76, higher than any other stock or mutual fund with a history of more than 30 years, and Berkshire has a significant alpha to traditional risk factors. However, we find that the alpha becomes insignificant when controlling for exposures to Betting-Against-Beta...... in publicly traded stocks versus wholly-owned private companies, we find that the former performs the best, suggesting that Buffett's returns are more due to stock selection than to his effect on management. These results have broad implications for market efficiency and the implementability of academic...

  19. Inhibition of Hypoxia Inducible Factor Alpha and Astrocyte-Elevated Gene-1 Mediates Cryptotanshinone Exerted Antitumor Activity in Hypoxic PC-3 Cells

    Directory of Open Access Journals (Sweden)

    Hyo-Jeong Lee

    2012-01-01

    Full Text Available Although cryptotanshinone (CT was known to exert antitumor activity in several cancers, its molecular mechanism under hypoxia still remains unclear. Here, the roles of AEG-1 and HIF-1α in CT-induced antitumor activity were investigated in hypoxic PC-3 cells. CT exerted cytotoxicity against prostate cancer cells and suppressed HIF-1α accumulation and AEG-1 expression in hypoxic PC-3 cells. Also, AEG-1 was overexpressed in prostate cancer cells. Interestingly, HIF-1α siRNA transfection enhanced the cleavages of caspase-9,3, and PAPR and decreased expression of Bcl-2 and AEG1 induced by CT in hypoxic PC-3 cells. Of note, DMOG enhanced the stability of AEG-1 and HIF-1α during hypoxia. Additionally, CT significantly reduced cellular level of VEGF in PC-3 cells and disturbed tube formation of HUVECs. Consistently, ChIP assay revealed that CT inhibited the binding of HIF-1α to VEGF promoter. Furthermore, CT at 10 mg/kg suppressed the growth of PC-3 cells in BALB/c athymic nude mice by 46.4% compared to untreated control. Consistently, immunohistochemistry revealed decreased expression of Ki-67, CD34, VEGF, carbonic anhydrase IX, and AEG-1 indices in CT-treated group compared to untreated control. Overall, our findings suggest that CT exerts antitumor activity via inhibition of HIF-1α, AEG1, and VEGF as a potent chemotherapeutic agent.

  20. Prostaglandin analogs in the treatment of glaucoma.

    Science.gov (United States)

    Hejkal, T W; Camras, C B

    1999-09-01

    Prostaglandin (PG) analogs are some of the most recent additions to the list of ocular hypotensive medications. Two analogs of naturally occurring PGs are available commercially, isopropyl unoprostone (Rescula [Ciba Vision, Atlanta, GA]) and latanoprost (Xalatan [Pharmacia & Upjohn, Bridgewater, NJ]). Presently, latanoprost 0. 005% is the only PG analog commercially available in the United States. These agents have been shown to be the most effective topical medications for reducing intraocular pressure. They have a different mechanism of action than other ocular hypotensives, and act primarily by increasing uveoscleral outflow. Because of this, PGs have a substantial additive effect when used with agents that reduce aqueous production (eg, beta blockers or carbonic anhydrase inhibitors) or that increase trabecular outflow facility (eg, pilocarpine). Local side effects include mild conjunctival hyperemia and local irritation, darkening of iris color, increased growth of eyelashes, and a possible association with cystoid macular edema or iritis in some patients with other risk factors. No systemic side effects have been proven to be caused by latanoprost. Recommended dosing is once daily at bedtime.

  1. 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.

  2. Methanol Extract of Hydroclathrus clathratus Inhibits Production of ...

    African Journals Online (AJOL)

    Methanol Extract of Hydroclathrus clathratus Inhibits Production of Nitric Oxide, Prostaglandin E2 and Tumor Necrosis Factor-α in Lipopolysaccharidestimulated BV2 Microglial Cells via Inhibition of NF-κB Activity. RGPT Jayasooriya, D-O Moon, YH Chol, C-H Yoon, G-Y Kim ...

  3. Inhibition of human prostate cancer cells proliferation by a selective alpha1-adrenoceptor antagonist labedipinedilol-A involves cell cycle arrest and apoptosis

    International Nuclear Information System (INIS)

    Liou, S.-F.; Lin, H.-H.; Liang, J.-C.; Chen, I.-J.; Yeh, J.-L.

    2009-01-01

    In this research, we conducted an in vitro analysis to evaluate the prostate cancer cells response to labedipinedilol-A in order to determine the effect of this selective α 1 -adrenoceptor antagonist to suppress prostate cancer cell growth by affecting cell proliferation and apoptosis. Here, we report that treatment of androgen-sensitive (LNCaP) and androgen-insensitive (PC-3) prostate cancer cells with labedipinedilol-A inhibited cell proliferation in concentration-dependent and time-dependent manners. Moreover, norepinephrine-stimulated proliferation of both cell lines are markedly inhibited by labedipinedilol-A. The probable involvement of α 1 -adrenoceptors in this cellular response is suggested. Labedipinedilol-A-induced growth inhibition was associated with G 0 /G 1 arrest, and G 2 /M arrest depending upon concentrations. Cell cycle blockade was associated with reduced amounts of cyclin D1/2, cyclin E, Cdk2, Cdk4, and Cdk6 and increased levels of the Cdk inhibitory proteins (Cip1/p21 and Kip1/p27). In addition, labedipinedilol-A also induced apoptosis in PC-3 cells, as determined by using Hoechst 33342 staining, DNA fragmentation, and Annexin V staining assay. Furthermore, labedipinedilol-A triggered the mitochondrial apoptotic pathway, as indicated by increasing the expression of Bax, but decreasing the level of Bcl-2, resulting in mitochondrial membrane potential loss, cytochrome c release, and activation of caspase-9 and -3. We further investigated the role of MAPK cascades in the anti-proliferative and apoptosis effects of labedipinedilol-A, and confirmed that labedipinedilol-A could activate JNK1/2 but not p38 in both cell lines. Unlike JNK1/2, however, labedipinedilol-A treatment resulted in down-regulation of phospho-ERK1/2 expression. We concluded that labedipinedilol-A possessed the growth-suppressive and apoptotic effects on LNCaP and PC-3 cells by its α 1 -adrenoceptor blockade, and the apoptotic effects of labedipinedilol-A primarily through

  4. Luteolin inhibits microglial inflammation and improves neuron survival against inflammation.

    Science.gov (United States)

    Zhu, Li-Hong; Bi, Wei; Qi, Ren-bin; Wang, Hua-dong; Lu, Da-xiang

    2011-06-01

    Microglia activation is one of the causative factors for neuroinflammation, which results in brain damage during neurodegenerative disease. Accumulating evidence has shown that the flavonoid luteolin (Lut) possesses potent anti-inflammatory properties; however, its effect on microglia inhibition is currently unknown. Moreover, it is not clear whether Lut also has indirect neuroprotective effects by reducing inflammatory mediators and suppressing microglia activation. In this study, we examined the effects of Lut on lipopolysaccharide (LPS)-induced proinflammatory mediator production and signaling pathways in murine BV2 microglia. In addition, we cocultured microglia and neurons to observe the indirect neuroprotective effects of Lut. Lut inhibited the LPS-stimulated expression of inducible NO synthase (iNOS), cyclooxygenase-2 (COX-2), tumor necrosis factor alpha (TNF-α), and interleukin-1β (IL-1β) as well as the production of nitric oxide (NO) and prostaglandin E(2) (PGE(2)). Moreover, Lut blocked LPS-induced nuclear factor kappa B (NF-κB) activation. Preincubation of microglia with Lut diminished the neurotoxic effects, owing to the direct anti-inflammatory effects of the compound. Taken together, our findings suggest that Lut may have a potential therapeutic application in the treatment of neuroinflammatory disorders. Copyright © 2011 Informa Healthcare USA, Inc.

  5. Effects of prostaglandin E2 and prostaglandin inhibitors on adrenal regeneration hypertension.

    Science.gov (United States)

    Paulson, D J; Eversole, W J

    1977-02-01

    The effects of prostaglandin E2 (PGE2) and a prostaglandin inhibitor, indomethacin, on the development of adrenal regeneration hypertension (ARH) were investigated. Weanling female rats underwent right adrenonephrectomy and left adrenal enucleation. PGE2 was injected subcutaneously daily in dosages of 0, 20, 40 and 80 mug/day. Indomethacin, 1 mg/kg, was administered twice daily by gavage. Blood pressures were determined by a tail and cuff plethysmographic method at 3, 5, and 7 wk after surgery. Increases in dosage of PGE2 produced a progressive reduction in mean blood pressures, heart, and kidney weights. Indomethacin produced significant increases in mean blood pressure, heart, kidney, and adrenal weights. The effects of aspirin and indomethacin on the blood pressures of rats with right adrenalectomy, left adrenal enucleation, and intact kidneys were studied. Administration of asprin twice daily (25 or 50 mg/kg) produced a fall in blood pressure, body and heart weight. Administration of 1 mg/kg twice daily of indomethacin resulted in a significant increase in blood pressure at 3 wk, and 0.1 or 1 mg/kg caused significant increases at 5 wk. The heart, kidney, and adrenal weights also showed increases with indomethacin administration. This study suggests that a deficiency of renal PGE2 may be involved in the etiology of ARH.

  6. Impotence evaluated by the use of prostaglandin E1

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, T.I.; Yang, C.R.; Wang, S.J.; Chang, C.L.; Tzai, T.S.; Chang, C.H.; Wu, H.C.

    1989-06-01

    We screened 80 patients at our hospital for the differential diagnosis of impotence using intracavernous injection of prostaglandin E1 (20 micrograms). The rate of positive response was 78.8 per cent (63 patients). Neither systemic reactions nor priapism occurred. However, a considerable incidence (23.8 per cent, 19 of 80 patients) of tolerable injection pain was encountered. The 133-xenon penile washout study was conducted routinely in impotent men for hemodynamic evaluation of penile vascularity. In 80 patients a positive correlation between the response of intracavernous prostaglandin E1 injection and the result of the washout study was found (r equals 0.381, p less than 0.0002). We selected 14 subjects randomly to receive additional intravenous infusions of prostaglandin E1 (6 ampules, 120 micrograms total) for 3 days, after which another 133-xenon washout study was done. The washout studies before and after intravenous prostaglandin E1 infusion were compared, and 10 patients (71.4 per cent) appeared to obtain improvement in half-time clearance and penile blood flow. However, only 3 patients noticed improvement subjectively. We suggest that prostaglandin E1 could be a desirable alternative for the diagnosis and treatment of impotence.

  7. Impotence evaluated by the use of prostaglandin E1

    International Nuclear Information System (INIS)

    Hwang, T.I.; Yang, C.R.; Wang, S.J.; Chang, C.L.; Tzai, T.S.; Chang, C.H.; Wu, H.C.

    1989-01-01

    We screened 80 patients at our hospital for the differential diagnosis of impotence using intracavernous injection of prostaglandin E1 (20 micrograms). The rate of positive response was 78.8 per cent (63 patients). Neither systemic reactions nor priapism occurred. However, a considerable incidence (23.8 per cent, 19 of 80 patients) of tolerable injection pain was encountered. The 133-xenon penile washout study was conducted routinely in impotent men for hemodynamic evaluation of penile vascularity. In 80 patients a positive correlation between the response of intracavernous prostaglandin E1 injection and the result of the washout study was found (r equals 0.381, p less than 0.0002). We selected 14 subjects randomly to receive additional intravenous infusions of prostaglandin E1 (6 ampules, 120 micrograms total) for 3 days, after which another 133-xenon washout study was done. The washout studies before and after intravenous prostaglandin E1 infusion were compared, and 10 patients (71.4 per cent) appeared to obtain improvement in half-time clearance and penile blood flow. However, only 3 patients noticed improvement subjectively. We suggest that prostaglandin E1 could be a desirable alternative for the diagnosis and treatment of impotence

  8. Effect Of Prostaglandins On Renal Function In Uninephrectomized Sheep

    International Nuclear Information System (INIS)

    Elsayed, Y.; ZIADA, G.

    2013-01-01

    Immediately after unilateral nephrectomy, different mechanisms of compensatory adaptation begin to act followed by a restoration of sufficient kidney function in a short time period. Some animal studies showed that prostaglandins (PG) are important for renal function after unilateral nephrectomy. The aim of the present study was to investigate the role of prostaglandins on renal function in the fully adapted remnant kidney in healthy uninephrectomized sheep and the acute effect of indomethacin on renal haemodynamics. In order to investigate the importance of prostaglandins on the renal function in the fully adapted remnant kidney, indomethacin (0.8 mg/kg) was injected intravenously immediately before and after unilateral nephrectomy. Forty sheep with unilateral nephrectomy were divided randomly into two groups; twenty sheep (group 1) untreated with indomethacin (unsuppressed PG) and the other twenty ones (group 2) were treated with indomethacin (suppressed PG) before and after clamping the renal pedicle and then instantaneously, the glomerular filtration rate (GFR) and the effective renal plasma flow (ERPF) were measured using non-invasive radionuclide technique then the filtration fraction (FF) was calculated. The study showed that there was considerable and instantaneous increase in GFR (148%) and a proportionate increase in the ERPF (91%) in the remaining kidney post-uninephrectomy, and treatment with indomethacin for suppression of prostaglandins synthesis showed non-significant changes in these measured values. The present study showed enhanced function, as measured by GFR and ERPF, in the remaining kidney as a compensatory effect of unilateral nephrectomy and the changes are not prostaglandins mediated

  9. Compartmentalization of prostaglandins in the canine kidney

    International Nuclear Information System (INIS)

    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 2 , measured as 6-keto-pGF/sub 1α/, 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 1α/ caused marked increases in both the urinary excretion and the renal venous outflow to 6-keto-PGF/sub 1α/. When 3 H-6-keto-PGF/sub 1α/ 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 3 H-PGl 2 and inulin, 20% of the radioactivity and 28% of the inulin reached the urine on first pass. Radioactive PGl 2 appeared to be less filterable at the glomeruli than either 3 H-6-keto-PGF/sub 1α/ or inulin. In the final set of experiments, in which dogs were prepared for a ureteral stopped-flow study, the PGE 2 /U/P/sub In/ ratio a peak was observed proximal to the Na + 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 2 synthesized in the kidney enters both the renal and tubular compartments. In contrast, they find that 6-keto-PGF/sub 1α/ of renal origin enters only the renal origin enters only the renal vascular compartment and not the tubular compartment

  10. 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.

  11. Liver AP-1 activation due to carbon tetrachloride is potentiated by 1,2-dibromoethane but is inhibited by alpha-tocopherol or gadolinium chloride.

    Science.gov (United States)

    Camandola, S; Aragno, M; Cutrin, J C; Tamagno, E; Danni, O; Chiarpotto, E; Parola, M; Leonarduzzi, G; Biasi, F; Poli, G

    1999-05-01

    Experimental acute intoxication by prooxidant haloalkanes produces marked stimulation of hepatic lipid peroxidation and cytolysis, which is followed by tissue regeneration. Our aim was to clarify the role of oxidative imbalance in the activation of the redox-sensitive transcription factor, activator protein-1 (AP-1), which is involved in tissue repair. Rats were poisoned with a very low concentration of carbon tetrachloride, given alone or in combination with another hepatotoxin, 1,2-dibromoethane, to provide varying extents of oxidative damage. The level of AP-1-DNA binding was analyzed by electrophoretic mobility shift assay on liver extracts, obtained from rats killed 6 h after poisoning. Stimulation of lipid peroxidation and AP-1 upregulation were already established when the hepatic damage due to carbon tetrachloride +/-1,2-dibromoethane was beginning to appear. Rat supplementation with the antioxidant vitamin E completely inhibited AP-1 upregulation, thus supporting a causative role of membrane lipid oxidation in the observed modulation of the transcription factor. Moreover, activation of Kupffer cells appears to be a crucial step in the increased AP-1 binding to DNA, the latter being largely prevented by gadolinium chloride, a macrophage-specific inhibitor.

  12. TNF-alpha inhibition could reduce biomarkers of endothelial dysfunction in patients with moderate to severe psoriasis: A 52-week echo-Doppler based quasi-experimental study.

    Science.gov (United States)

    Molina-Leyva, Alejandro; Garrido-Pareja, Fermín; Ruiz-Carrascosa, José Carlos; Ruiz-Villaverde, Ricardo

    2017-10-28

    Psoriasis is associated to endothelial dysfunction, which causes impaired vascular functioning. TNF-α blockers have shown the ability to improve vascular functioning in psoriasis. The nailfold vessel resistance index (NVRI) assesses microvascular functioning at nailfold. The objectives of the study is to assess the effect of the TNF-α inhibition with adalimumab on NVRI. Quasi-experimental study. Fifteen patients with moderate-severe psoriasis received adalimumab 40mg sc according to label information. Participants were assessed at baseline and at 12, 24 and 52 weeks after study intervention. A reduction of -0.09±0.02 (P<.01) in NVRI and a -11.2±2,41ng/ml (P<.001) in E-selectin was observed at week 52. Adalimumab could produce a progressive and sustained reduction of vessel resistance at nailfold and E-selectin in patients with psoriasis. Copyright © 2017 Elsevier España, S.L.U. All rights reserved.

  13. Involvement of the clock gene Rev-erb alpha in the regulation of glucagon secretion in pancreatic alpha-cells.

    Directory of Open Access Journals (Sweden)

    Elaine Vieira

    Full Text Available Disruption of pancreatic clock genes impairs pancreatic beta-cell function, leading to the onset of diabetes. Despite the importance of pancreatic alpha-cells in the regulation of glucose homeostasis and in diabetes pathophysiology, nothing is known about the role of clock genes in these cells. Here, we identify the clock gene Rev-erb alpha as a new intracellular regulator of glucagon secretion. Rev-erb alpha down-regulation by siRNA (60-70% inhibition in alphaTC1-9 cells inhibited low-glucose induced glucagon secretion (p<0.05 and led to a decrease in key genes of the exocytotic machinery. The Rev-erb alpha agonist GSK4112 increased glucagon secretion (1.6 fold and intracellular calcium signals in alphaTC1-9 cells and mouse primary alpha-cells, whereas the Rev-erb alpha antagonist SR8278 produced the opposite effect. At 0.5 mM glucose, alphaTC1-9 cells exhibited intrinsic circadian Rev-erb alpha expression oscillations that were inhibited by 11 mM glucose. In mouse primary alpha-cells, glucose induced similar effects (p<0.001. High glucose inhibited key genes controlled by AMPK such as Nampt, Sirt1 and PGC-1 alpha in alphaTC1-9 cells (p<0.05. AMPK activation by metformin completely reversed the inhibitory effect of glucose on Nampt-Sirt1-PGC-1 alpha and Rev-erb alpha. Nampt inhibition decreased Sirt1, PGC-1 alpha and Rev-erb alpha mRNA expression (p<0.01 and glucagon release (p<0.05. These findings identify Rev-erb alpha as a new intracellular regulator of glucagon secretion via AMPK/Nampt/Sirt1 pathway.

  14. 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....

  15. Zearalenone and alpha-zearalenol inhibit the synthesis and secretion of pig follicle stimulating hormone via the non-classical estrogen membrane receptor GPR30.

    Science.gov (United States)

    He, Jing; Wei, Chao; Li, Yueqin; Liu, Ying; Wang, Yue; Pan, Jirong; Liu, Jiali; Wu, Yingjie; Cui, Sheng

    2018-02-05

    Zearalenone (ZEA) is one of the most popular endocrine-disrupting chemicals and is mainly produced by fungi of the genus Fusarium. The excessive intake of ZEA severely disrupts human and animal fertility by affecting the reproductive axis. However, most studies on the effects of ZEA and its metabolite α-zearalenol (α-ZOL) on reproductive systems have focused on gonads. Few studies have investigated the endocrine-disrupting effects of ZEA and α-ZOL on pituitary gonadotropins, including follicle-stimulating hormone (FSH) and luteinizing hormone (LH). The present study was designed to investigate the effects of ZEA and α-ZOL on the synthesis and secretion of FSH and LH and related mechanisms in female pig pituitary. Our in vivo and in vitro results demonstrated that ZEA significantly inhibited the synthesis and secretion of FSH in the pig pituitary gland, but ZEA and α-ZOL had no effects on LH. Our study also showed that ZEA and α-ZOL decreased FSH synthesis and secretion through non-classical estrogen membrane receptor GPR30, which subsequently induced protein kinase cascades and the phosphorylation of PKC, ERK and p38MAPK signaling pathways in pig pituitary cells. Furthermore, our study showed that the LIM homeodomain transcription factor LHX3 was involved in the mechanisms of ZEA and α-ZOL actions on gonadotropes in the female pig pituitary. These findings elucidate the mechanisms behind the physiological alterations resulting from endocrine-disrupting chemicals and further show that the proposed key molecules of the α-ZOL signaling pathway could be potential pharmacological targets. Copyright © 2017. Published by Elsevier B.V.

  16. Sestrin2 induced by hypoxia inducible factor1 alpha protects the blood-brain barrier via inhibiting VEGF after severe hypoxic-ischemic injury in neonatal rats.

    Science.gov (United States)

    Shi, Xudan; Doycheva, Desislava Met; Xu, Liang; Tang, Jiping; Yan, Min; Zhang, John H

    2016-11-01

    Hypoxic ischemic (HI) encephalopathy remains the leading cause of perinatal brain injury resulting in long term disabilities. Stabilization of blood brain barrier (BBB) after HI is an important target, therefore, in this study we aim to determine the role of sestrin2, a stress inducible protein which is elevated after various insults, on BBB stabilization after moderate and severe HI injuries. Rat pups underwent common carotid artery ligation followed by either 150min (severe model) or 100min (moderate model) of hypoxia. 1h post HI, rats were intranasally administered with recombinant human sestrin2 (rh-sestrin2) and sacrificed for infarct area, brain water content, righting reflex and geotaxis reflex. Sestrin2 was silenced using siRNA and an activator/inhibitor of hypoxia inducible factor1α (HIF1α) was used to examine their roles on BBB permeability. Rats subjected to severe HI exhibited larger infarct area and higher sestrin2 expression compared to rats in the moderate HI group. rh-sestrin2 attenuated brain infarct and edema, while silencing sestrin2 reversed these protective effects after severe HI. HIF1α induced sestrin2 activation in severe HI but not in moderate HI groups. A HIF1a agonist was shown to increase permeability of the BBB via vascular endothelial growth factor (VEGF) after moderate HI. However, after severe HI, HIF1α activated both VEGF and sestrin2. But HIF1α dependent sestrin2 activation was the predominant pathway after severe HI which inhibited VEGF and attenuated BBB permeability. rh-sestrin2 attenuated BBB permeability via upregulation of endogenous sestrin2 which was induced by HIF1α after severe HI. However, HIF1α's effects as a prodeath or prosurvival signal were influenced by the severity of HI injury. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. Alpha-amylase, α-glucosidase and lipase inhibiting activities of polyphenol-rich extracts from six common bean cultivars of Southern Italy, before and after cooking.

    Science.gov (United States)

    Ombra, Maria Neve; d'Acierno, Antonio; Nazzaro, Filomena; Spigno, Patrizia; Riccardi, Riccardo; Zaccardelli, Massimo; Pane, Catello; Coppola, Raffaele; Fratianni, Florinda

    2018-01-16

    Common beans (Phaseolus vulgaris) are a good source of nutrients and phenolic compounds with versatile health benefits. Polyphenol-rich extracts of six ecotypes of P. vulgaris were analysed to determine their phenolic profiles and assayed in vitro for inhibitory effects on digestive enzymes relevant to carbohydrates and lipids metabolism. The extracts inhibited enzyme activities in a dose-dependent manner. IC 50 values ranged from 69 ± 1.9 to 126 ± 3.2 μg/mL and from 107.01 ± 4.5 to 184.20 ± 5.7 μg/mL, before and after cooking, for α-amylase, from 39.3 ± 4.4 to 74.13 ± 6.9 μg/mL and from 51 ± 7.7 to 122.1 ± 5.2 μg/mL for α-glucosidase and from 63.11 ± 7.5 to 103.2 ± 5.9 μg/mL and from 92.0 ± 6.3 to 128.5 ± 7.4 μg/mL for lipase. Results suggest encouraging their consumption, being natural sources of enzyme inhibitors important for type-2 diabetes and obesity prevention/control. Well-monitored in vivo studies would help to establish their beneficial effects, making them worthwhile of further consideration as functional foods.

  18. Effect of Aspirin and Indomethacin on Prostaglandin E2 Synthesis in C6 Glioma Cells

    Directory of Open Access Journals (Sweden)

    Shiuh-Lin Hwang

    2004-01-01

    Full Text Available Prostaglandin E2 (PGE2 plays an important role in immunosuppression and tumor growth. PGE2 inhibitors such as aspirin and indomethacin suppress experimental tumor growth. Little is known of the relationship between PGE2 synthesis in brain tumors and the dose of aspirin or indomethacin. The present study was undertaken to evaluate the effect of different doses of aspirin and indomethacin on PGE2 synthesis in C6 glioma cells. C6 glioma cells were incubated with different concentrations (2, 4, and 8 μM of aspirin and indomethacin for 1, 2, 4, 6, 8, 12, and 24 hours. Intracellular PGE2 concentration was measured by enzyme immunoassay. Each concentration of aspirin and indomethacin effectively inhibited PGE2 synthesis. Concentrations of 2, 4, and 8 μM of aspirin significantly inhibited PGE2 production at 6, 4, and 1 hours, respectively, and the inhibition persisted for more than 24 hours (p 0.05. Indomethacin 8 μM was effective at 1 hour and the inhibition persisted beyond 24 hours (p < 0.05. Our study demonstrates that aspirin and indomethacin inhibit PGE2 synthesis in C6 glioma cells and that low-dose aspirin is as effective as high-dose aspirin. This study may encourage future clinical use of low-dose aspirin in the prevention or treatment of brain tumors.

  19. Enzymatic synthesis of tritium-labelled prostaglandin D2 and its conversion to other prostaglandins

    International Nuclear Information System (INIS)

    Shram, S.I.; Lazurkina, T.Yu.; Shevchenko, V.P.; Nagaev, I.Yu.; Myasoedov, N.F.

    1994-01-01

    The one-stage enzymatic synthesis of tritium-labelled prostaglandin D 2 from labelled arachidonic acid was performed by using the enzyme system PGH-synthetase/PGH-PGD-isomerase. By enzymatic and chemical transformation of [ 3 H]PGD 2 the following compounds were obtained: 15-keto-13,14-dihydro-[ 3 H]PGD 2 , 9α,11β-[ 3 H]PGF 2 , 9-deoxy-Δ 9 -[ 3 H]-PGD 2 ([ 3 H]PGJ 2 ) and Δ 12 -13,14-dihydro-[ 3 H]PGJ 2 . It was found that L-selectride is a more effective reducing agent than sodium borohydride in the synthesis of 9α, 11β-[ 3 H]PGF 2 . (Author)

  20. Interleukin-10 does not mediate the inhibitory effect of PDE-4 inhibitors and other cAMP-elevating drugs on lipopolysaccharide-induced tumors necrosis factor-alpha generation from human peripheral blood monocytes.

    Science.gov (United States)

    Seldon, P M; Barnes, P J; Giembycz, M A

    1998-01-01

    Lipopolysaccharide (LPS)-induced liver injury in mice and LPS-induced tumor necrosis factor-alpha (TNF-alpha) generation by murine macrophages and hepatocytes are suppressed markedly by agents that elevate intracellular cAMP. Phosphodiesterase (PDE)-4 inhibitors, beta 2-adrenoceptor agonists, and E-series prostaglandins also attenuate the induction of the TNF-alpha gene in human monocytes in response to bacterial LPS. The mechanism of action of cAMP is unclear, but in the mouse, is believed to involve the generation of this anti-inflammatory cytokine, interleukin-10 (IL-10). In this article, we describe the results of studies designed to determine the extent to which IL-10 contributes to the suppression of TNF-alpha generation from LPS-stimulated human monocytes evoked by 8-bromo cyclic AMP (8-Br-cAMP), rolipram, salbutamol, and prostaglandin E2 (PGE2). LPS evoked a time- and concentration-dependent generation of TNF-alpha (t1/2 = 4.5 h; EC50 = 273 pg/mL), which was inhibited by exogenous human recombinant (h) IL-10 (IC50 = 124 pg/mL), and by rolipram (EC50 = 420 nM), 8-Br-cAMP (EC50 = 77 (microM), PGE2 (EC50 = 15 nM) and salbutamol (EC50 = 20 nM). In addition, 8-Br-cAMP, PGE2; and salbutamol (but not rolipram) augmented significantly LPS-induced IL-10 production (two-to-fivefold) under identical experimental conditions. Pretreatment of monocytes with an anti-IL-10 monoclonal antibody (MAb) that abolished the inhibitory action of a maximally effective concentration of exogenous hrIL-10, failed to attenuate the inhibitory effect of rolipram, PGE2, salbutamol, and 8-Br-cAMP. Anti-IL-10 was similarly inactive when the number of monocytes seeded was increased from 0.5 to 4 x 10(6)/mL or when measurements were made at 42 h post-LPS, a time when the concentration of IL-10 released was maximal. Collectively, these data suggest that in contrast to murine hepatocytes and macrophages, IL-10 does not mediate the inhibitory effect of cAMP-elevating drugs on TNF-alpha

  1. Antisense myb inhibition of purified erythroid progenitors in development and differentiation is linked to cycling activity and expression of DNA polymerase alpha

    International Nuclear Information System (INIS)

    Valtieri, M.; Venturelli, D.; Care, A.; Fossati, C.; Pelosi, E.; Labbaye, C.; Mattia, G.; Gewirtz, A.M.; Calabretta, B.; Peschle, C.

    1991-01-01

    These studies aimed to determine the expression and functional role of c-myb in erythroid progenitors with different cycling activities. In the first series of experiments the erythroid burst-forming unit (BFU-E) and colony-forming unit (CFU-E) populations from adult peripheral blood (PB), bone marrow (BM), and embryonic-fetal liver (FL) were treated with either c-myb antisense oligomers or 3H-thymidine (3H-TdR). A direct correlation was always observed between the inhibitory effect of anti-myb oligomers and the level of cycling activity. Thus, the inhibitory effect of antisense c-myb on the number of BFU-E colonies was 28.3% +/- 15.8% in PB, 53.4% +/- 9.3% in BM, and 68.2% +/- 24.5% in FL. Both adult and embryonic CFU-E were markedly inhibited. Using purified PB progenitors, we observed a similar pattern, although with slightly lower inhibitory effects. In the 3H-TdR suicide assay the killing index of BFU-E was 8.9% +/- 4.2% in PB, 29.4% +/- 6.5% in BM, and 40.1% +/- 9.6% in FL. The values for adult and embryonic CFU-E were 55.7% +/- 7.9% and 60.98% +/- 6.6%, respectively. We then investigated the kinetics of c-myb mRNA level during the erythroid differentiation of purified adult PB and FL BFU-E, as evaluated in liquid-phase culture by reverse transcription-polymerase chain reaction. Adult erythroid precursors showed a gradual increase of c-myb mRNA from day 4 through day 8 of culture and a sharp decrease at later times, whereas the expression of c-myb mRNA and protein in differentiation embryonic precursors peaked 2 days earlier. In both cases, c-myb mRNA level peaked at the CFU-E stage of differentiation. Finally, highly purified adult PB BFU-E were stimulated into cycling by a 3-day treatment with interleukin-3 in liquid phase: both the sensitivity to c-myb antisense oligomers and the 3H-TdR suicide index showed a gradual, strictly parallel increase

  2. The influence of some prostaglandins on DNA synthesis and DNA excision repair in mouse spleen cells ''in vitro''

    International Nuclear Information System (INIS)

    Klein, W.; Altmann, H.; Kocsis, F.; Egg, D.; Guenther, R.

    1978-03-01

    ''In vitro'' experiments were performed on mouse spleen cells to establish possible influences of some naturally occurring prostaglandins on DNA synthesis and DNA excision repair. The prostaglandins A 1 , B 1 , E 1 , E 2 and Fsub(2α) were tested in concentrations of 10 pg, 5 ng and 2,5μg per ml cell suspension. DNA synthesis was significantly increased by PgFsub(2α) in all the three concentrations tested, while the other tested prostaglandins were essentially ineffective. DNA excision repair was significantly inhibited by PgE 1 and PgE 2 at 5 ng/ml and at 2,5 μg/ml but increased by PgFsub(2α) in the two lower concentrations. The rejoining of DNA-strand breaks after gamma-irradiation was slightly reduced by PgE 1 , PgE 2 and PgF 2 at 2,5 μg/ml. (author)

  3. Beneficial effects of intra-arterial and intravenous prostaglandin E1 in intestinal ischaemia-reperfusion injury.

    Science.gov (United States)

    San Norberto García, Enrique María; Taylor, James Henry; Cenizo, Noelia; Vaquero, Carlos

    2014-04-01

    Ischaemia-reperfusion (I/R) injury is encountered in conditions that diminish intestinal blood flow. There is no clinically feasible technique available for mucosal preservation. One hundred Wistar rats were subjected to intestinal ischaemia for 15 and 60 min (I15', I60'), followed by 1 and 7 days of reperfusion (R1d, R7d). Rats were subjected to ischaemia by clamping the superior mesenteric artery. Prostaglandin E1 (PGE1) (2.500 ng/kg intra-arterial bolus or 20 ng/kg intravenous infusion) was administered immediately prior to the commencement of the experimental period. Animals were divided into 20 groups: sham (laparotomy alone), sacrificed at 1 or 7 days; saline administration, 15 or 60 min of ischaemia, 1 or 7 days of reperfusion; prostaglandin E1 administration, 15 or 60 min of ischaemia, 1 or 7 days of reperfusion, each one for intra-arterial or intravenous administration. Ileal segments were excised and assessed for histopathological score, polymorphonuclear (PMN) leucocytes encountered and myeloperoxidase (MPO) activity measurement. I/R caused deterioration of histological characteristics. Prophylactic administration of PGE1 resulted in a significant decrease in the histological score compared with the respective saline group (analysis of variance, P prostaglandin E1 prevents I/R injury by diminishing histological damage parameters, inhibiting PMN leucocyte infiltration and attenuating MPO activity.

  4. Prostaglandin biosynthesis, transport, and signaling in corpus luteum: a basis for autoregulation of luteal function.

    Science.gov (United States)

    Arosh, J A; Banu, S K; Chapdelaine, P; Madore, E; Sirois, J; Fortier, M A

    2004-05-01

    The corpus luteum (CL) is a transient ovarian endocrine gland formed from the ovulated follicle. Progesterone is the primary secretory product of CL and is essential for establishment of pregnancy in mammals. In the cyclic female, the life span of CL is characterized by luteal development, maintenance, and regression regulated by complex interactions between luteotrophic and luteolytic mediators. It is universally accepted that prostaglandin (PG) F(2a) is the luteolysin whereas PGE(2) is considered as a luteotropin in most mammals. New emerging concepts emphasize the autocrine and paracrine actions of luteal PGs in CL function. However, there is no report on selective biosynthesis and cellular transport of luteal PGE(2) and PGF(2alpha) in the CL of any species. We have studied the expression of enzymes involved in the metabolism of PGE(2) and PGF(2alpha), cyclooxygenase (COX)-1 and -2, PGE and F synthases, PG 15-dehydrogenase, and PG transporter as well as receptors (EP2, EP3, and FP) throughout the CL life span using a bovine model. COX-1, PGF synthase, and PG 15-dehydrogenase are expressed at constant levels whereas COX-2, PGE synthase, PG transporter, EP2, EP3, and FP are highly modulated during different phases of the CL life span. The PG components are preferentially expressed in large luteal cells. The results indicate that PGE(2) biosynthesis, transport, and signaling cascades are selectively activated during luteal maintenance. By contrast the PGF(2alpha) system is activated during luteal regression. Collectively, our results suggest an integrated role for luteal PGE(2) and PGF(2alpha) in autoregulation of CL function.

  5. Effects of curcumin in pediatric epithelial liver tumors: inhibition of tumor growth and alpha-fetoprotein in vitro and in vivo involving the NFkappaB- and the beta-catenin pathways.

    Science.gov (United States)

    Bortel, Nicola; Armeanu-Ebinger, Sorin; Schmid, Evi; Kirchner, Bettina; Frank, Jan; Kocher, Alexa; Schiborr, Christina; Warmann, Steven; Fuchs, Jörg; Ellerkamp, Verena

    2015-12-01

    In children with hepatocellular carcinoma (pHCC) the 5-year overall survival rate is poor. Effects of cytostatic therapies such as cisplatin and doxorubicin are limited due to chemoresistance and tumor relapse. In adult HCC, several antitumor properties are described for the use of curcumin. Curcumin is one of the best-investigated phytochemicals in complementary oncology without relevant side effects. Its use is limited by low bioavailability. Little is known about the influence of curcumin on pediatric epithelial hepatic malignancies. We investigated the effects of curcumin in combination with cisplatin on two pediatric epithelial liver tumor cell lines. As mechanisms of action inhibition of NFkappaB, beta-catenin, and decrease of cyclin D were identified. Using a mouse xenograft model we could show a significant decrease of alpha-fetoprotein after combination therapy of oral micellar curcumin and cisplatin. Significant concentrations of curcuminoids were found in blood samples, organ lysates, and tumor tissue after oral micellar curcumin administration. Micellar curcumin in combination with cisplatin can be a promising strategy for treatment of pediatric HCC.

  6. Inhibition of Neuroinflammation in LPS-Activated Microglia by Cryptolepine

    Directory of Open Access Journals (Sweden)

    Olumayokun A. Olajide

    2013-01-01

    Full Text Available Cryptolepine, an indoloquinoline alkaloid in Cryptolepis sanguinolenta, has anti-inflammatory property. In this study, we aimed to evaluate the effects of cryptolepine on lipopolysaccharide (LPS- induced neuroinflammation in rat microglia and its potential mechanisms. Microglial activation was induced by stimulation with LPS, and the effects of cryptolepine pretreatment on microglial activation and production of proinflammatory mediators, PGE2/COX-2, microsomal prostaglandin E2 synthase and nitric oxide/iNOS were investigated. We further elucidated the role of Nuclear Factor-kappa B (NF-κB and the mitogen-activated protein kinases in the antiinflammatory actions of cryptolepine in LPS-stimulated microglia. Our results showed that cryptolepine significantly inhibited LPS-induced production of tumour necrosis factor-alpha (TNFα, interleukin-6 (IL-6, interleukin-1beta (IL-1β, nitric oxide, and PGE2. Protein and mRNA levels of COX-2 and iNOS were also attenuated by cryptolepine. Further experiments on intracellular signalling mechanisms show that IκB-independent inhibition of NF-κB nuclear translocation contributes to the anti-neuroinflammatory actions of cryptolepine. Results also show that cryptolepine inhibited LPS-induced p38 and MAPKAPK2 phosphorylation in the microglia. Cell viability experiments revealed that cryptolepine (2.5 and 5 μM did not produce cytotoxicity in microglia. Taken together, our results suggest that cryptolepine inhibits LPS-induced microglial inflammation by partial targeting of NF-κB signalling and attenuation of p38/MAPKAPK2.

  7. Estradiol-17β, prostaglandin E2 (PGE2) and the prostaglandin E2 receptor are involved in PGE2 positive feedback loop in the porcine endometrium

    Science.gov (United States)

    Waclawik, Agnieszka; Jabbour, Henry N.; Blitek, Agnieszka; Ziecik, Adam J.

    2009-01-01

    Before implantation, the porcine endometrium and trophoblast synthesize elevated amounts of luteoprotective prostaglandin E2 (PGE2). We hypothesized that embryo signal, estradiol-17β (E2) and PGE2 modulate expression of key enzymes in PG synthesis: prostaglandin-endoperoxide synthase-2 (PTGS2), PGE synthase (mPGES-1), PGF synthase (PGFS), and prostaglandin 9-ketoreductase (CBR1); as well as PGE2 receptor (PTGER2 and 4) expression and signaling within the endometrium. We determinated the site of action of PGE2 in endometrium during the estrous cycle and pregnancy. Endometrial tissue explants obtained from gilts (n=6) on days 11-12 of the estrous cycle were treated with vehicle (control), PGE2 (100 nM), E2 (1-100 nM) or phorbol 12-myristate 13-acetate (100 nM, positive control). E2 increased PGE2 secretion through elevating expression of mPGES-1 mRNA and PTGS2 and mPGES-1 protein in endometrial explants. By contrast, E2 decreased PGFS and CBR1 protein expression. E2 also stimulated PTGER2 but not PTGER4 protein content. PGE2 enhanced mPGES-1 and PTGER2 mRNA as well as PTGS2, mPGES-1 and PTGER2 protein expression. PGE2 had no effect on PGFS, CBR1 and PTGER4 expression and PGF2α release. Treatment of endometrial tissue with PGE2 increased cAMP production. Co-treatment with PTGER2 antagonist (AH6809) but not PTGER4 antagonist (GW 627368X) inhibited significantly PGE2-mediated cAMP production. PTGER2 protein was localized in luminal and glandular epithelium and blood vessels of endometrium, and was significantly up-regulated on days 11-12 of pregnancy. Our results suggest that E2, prevents luteolysis through enzymatic modification of PG synthesis and that E2, PGE2 and endometrial PTGER2 are involved in PGE2 positive feedback loop in porcine endometrium. PMID:19359378

  8. Crosstalk between the peroxisome proliferator-activated receptor {gamma} (PPAR{gamma}) and the vitamin D receptor (VDR) in human breast cancer cells: PPAR{gamma} binds to VDR and inhibits 1{alpha},25-dihydroxyvitamin D{sub 3} mediated transactivation

    Energy Technology Data Exchange (ETDEWEB)

    Alimirah, Fatouma; Peng, Xinjian; Yuan, Liang; Mehta, Rajeshwari R. [Cancer Biology Division, IIT Research Institute, 10 West 35th Street, Chicago, IL 60616 (United States); Knethen, Andreas von [Institute of Biochemistry, Johann Wolfgang Goethe University, Frankfurt (Germany); Choubey, Divaker [Department of Environmental Health, University of Cincinnati, 3223 Eden Avenue, P.O. Box 670056, Cincinnati, OH 45267 (United States); Mehta, Rajendra G., E-mail: rmehta@iitri.org [Cancer Biology Division, IIT Research Institute, 10 West 35th Street, Chicago, IL 60616 (United States)

    2012-11-15

    Heterodimerization and cross-talk between nuclear hormone receptors often occurs. For example, estrogen receptor alpha (ER{alpha}) physically binds to peroxisome proliferator-activated receptor gamma (PPAR{gamma}) and inhibits its transcriptional activity. The interaction between PPAR{gamma} and the vitamin D receptor (VDR) however, is unknown. Here, we elucidate the molecular mechanisms linking PPAR{gamma} and VDR signaling, and for the first time we show that PPAR{gamma} physically associates with VDR in human breast cancer cells. We found that overexpression of PPAR{gamma} decreased 1{alpha},25-dihydroxyvitamin D{sub 3} (1,25D{sub 3}) mediated transcriptional activity of the vitamin D target gene, CYP24A1, by 49% and the activity of VDRE-luc, a vitamin D responsive reporter, by 75% in T47D human breast cancer cells. Deletion mutation experiments illustrated that helices 1 and 4 of PPAR{gamma}'s hinge and ligand binding domains, respectively, governed this suppressive function. Additionally, abrogation of PPAR{gamma}'s AF2 domain attenuated its repressive action on 1,25D{sub 3} transactivation, indicating that this domain is integral in inhibiting VDR signaling. PPAR{gamma} was also found to compete with VDR for their binding partner retinoid X receptor alpha (RXR{alpha}). Overexpression of RXR{alpha} blocked PPAR{gamma}'s suppressive effect on 1,25D{sub 3} action, enhancing VDR signaling. In conclusion, these observations uncover molecular mechanisms connecting the PPAR{gamma} and VDR pathways. -- Highlights: PPAR{gamma}'s role on 1{alpha},25-dihydroxyvitamin D{sub 3} transcriptional activity is examined. Black-Right-Pointing-Pointer PPAR{gamma} physically binds to VDR and inhibits 1{alpha},25-dihydroxyvitamin D{sub 3} action. Black-Right-Pointing-Pointer PPAR{gamma}'s hinge and ligand binding domains are important for this inhibitory effect. Black-Right-Pointing-Pointer PPAR{gamma} competes with VDR for the availability of their binding

  9. Prostaglandin E1 facilitates inotropic effects of 5-HT4 serotonin receptors and β-adrenoceptors in failing human heart.

    Science.gov (United States)

    Riise, Jon; Ørstavik, Øivind; Qvigstad, Eirik; Dahl, Christen P; Osnes, Jan-Bjørn; Skomedal, Tor; Levy, Finn Olav; Krobert, Kurt A

    2012-09-01

    Prostaglandins have displayed both beneficial and detrimental effects in clinical studies in patients with severe heart failure. Prostaglandins are known to increase cardiac output, but the mechanism is not clarified. Here, we tested the hypothesis that prostaglandins can increase contractility in human heart by amplifying cAMP-dependent inotropic responses. Contractility was measured ex vivo in isolated left ventricular strips and phosphodiesterase (PDE) and adenylyl cyclase (AC) activity was measured in homogenates or membranes from failing human left ventricles. PGE(1) (1 µM) alone did not modify contractility, but given prior, amplified maximal serotonin (5-HT)-evoked (10 µM) contractile responses mediated by 5-HT(4) receptors several fold (24 ± 7 % with PGE(1) vs. 3 ± 2 % above basal with 5-HT alone). The 5-HT(4)-mediated inotropic response was amplified by the PDE3 inhibitor cilostamide and further amplified in combination with PGE(1) (26 ± 6 vs. 56 ± 12 % above basal). PGE(1) reduced the time to reach 90 % of both the maximal 5-HT- and isoproterenol-evoked inotropic response compared to 5-HT or isoproterenol alone. PGE(1) did not modify PDE activity in the homogenate, either alone or when given simultaneously with PDE3 and/or PDE4 inhibitors. Neither 5-HT- nor isoproterenol-stimulated AC activity was significantly amplified by PGE(1). Sensitivity of ventricular strips to Ca(2+) was not enhanced in the presence of PGE(1). Our results show that PGE(1) can enhance cAMP-mediated responses in failing human left ventricle, through a mechanism independent of PDE inhibition, amplification of AC activity or increasing sensitivity to calcium. This effect of PGE(1) possibly contributes to the increase of cardiac output, independent of decreased afterload, observed after prostaglandin administration in humans.

  10. Analytical and preparative resolution of enantiomers of prostaglandin precursors and prostaglandins by liquid chromatography on derivatized cellulose chiral stationary phases.

    Science.gov (United States)

    Miller, L; Weyker, C

    1990-07-06

    Analytical methods were developed for the separation of the enantiomers of four cyclopentenone precursors of prostaglandins. The resolution obtained is correlated with the chemical environment around the chiral center of the cyclopentenones. The analytical methods were scaled up to preparative loadings and the chromatographic parameters were varied to determine their effect on the preparative separations. The correlation between analytical resolution and preparative resolution was also investigated. In addition to the precursors, the preparative resolution of the enantiomers of a synthetic prostaglandin analogue was investigated.

  11. 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

    . In conclusion, PGE2 and PGI2 may protect renal perfusion by activating cognate IP and EP4 receptors associated with smooth muscle cells and endothelium in human intrarenal arteries and contribute to increased renal vascular resistance at high pathological concentrations mediated by noncognate TP receptor.......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...... and PGI2 induced concentration-dependent relaxation (-log EC50: PGE2=7.1±0.3 and PGI2=7.7). The response to PGE2 displayed endothelium dependence and desensitization. Relaxation by PGE2 was mimicked by an EP4 receptor agonist (CAY10598, EC50=6.7±0.2). The relaxation after PGI2 was abolished by an IP...

  12. Estradiol-17β, prostaglandin E2 (PGE2) and the prostaglandin E2 receptor are involved in PGE2 positive feedback loop in the porcine endometrium

    OpenAIRE

    Waclawik, Agnieszka; Jabbour, Henry N.; Blitek, Agnieszka; Ziecik, Adam J.

    2009-01-01

    Before implantation, the porcine endometrium and trophoblast synthesize elevated amounts of luteoprotective prostaglandin E2 (PGE2). We hypothesized that embryo signal, estradiol-17β (E2) and PGE2 modulate expression of key enzymes in PG synthesis: prostaglandin-endoperoxide synthase-2 (PTGS2), PGE synthase (mPGES-1), PGF synthase (PGFS), and prostaglandin 9-ketoreductase (CBR1); as well as PGE2 receptor (PTGER2 and 4) expression and signaling within the endometrium. We determinated the site ...

  13. Prostaglandin phospholipid conjugates with unusual biophysical and cytotoxic properties

    DEFF Research Database (Denmark)

    Pedersen, Palle Jacob; Adolph, Sidsel K.; Andresen, Thomas Lars

    2010-01-01

    The synthesis of two secretory phospholipase A(2) IIA sensitive 15-deoxy-Delta(12,14)-prostaglandin J(2) phospholipid conjugates is described and their biophysical and biological properties are reported. The conjugates spontaneously form particles in the liposome size region upon dispersion in an...

  14. Renin-sodium profile and renal prostaglandins in the pathogenesis ...

    African Journals Online (AJOL)

    Renin-sodium profile and renal prostaglandins in the pathogenesis of systemic arterial hypertension in blacks. L. Somova, J. Mufunda. Thirteen black women with systemic (essential) arterial hypertension, age-matched with normotensives, were examined during two protocols inducing sodium depletion and sodium loading ...

  15. Involvement of Kinin Kallikrein And Prostaglandin on TAME ...

    African Journals Online (AJOL)

    The effects of a kallikrein inhibitor and a prostaglandin inhibitor were investigated on TAME-esterase induced contractions on rat aorta in-vitro. The present findings showed that use of these inhibitors significantly reduced TAME-esterase contractions. Our work is the first to demonstrate involvement of both kinin kallikrein ...

  16. Prostaglandin levels and semen quality in male partners of infertile ...

    African Journals Online (AJOL)

    Objective: To provide data on semen prostaglandins in Nigerian men and relate this to fertility potential as provided by semen analysis results. Design: Prospective study. Setting: Infertility Clinic of Obafemi Awolowo University Teaching Hospitals Complex, Ile-Ife, Nigeria Subjects: All male partners of infertile couples who ...

  17. Pharmacologic specificity of alpha-2 adrenergic receptor subtypes

    Energy Technology Data Exchange (ETDEWEB)

    Petrash, A.; Bylund, D.

    1986-03-01

    The authors have defined alpha-2 adrenergic receptor subtypes in human and rat tissues using prazosin as a subtype selective drug. Prazosin has a lower affinity (250 nM) at alpha-2A receptor and a higher affinity (5 nM) at alpha-2B receptors. In order to determine if other adrenergic drugs are selective for one or the other subtypes, the authors performed (/sup 3/H)yohimbine inhibition experiments with various adrenergic drugs in tissues containing alpha-2A, alpha-2B or both subtypes. Oxymetazoline, WB4101 and yohimbine were found to be 80-, 20- and 10-fold more potent at alpha-2A receptors than at alpha-2B receptors. Phentolamine, adazoxan, (+)- and (-)-mianserin, clonidine, (+)-butaclamol, (-)- and (+)-norepinephrine, epinephrine, dopamine and thioridazine were found to have equal affinities for the two subtypes. These results further validate the subdivision of alpha-2 adrenergic receptors into alpha-2A and alpha-2B subtypes.

  18. Acetylsalicylic acid inhibits the growth of melanoma tumors via SOX2-dependent-PAF-R-independent signaling pathway.

    Science.gov (United States)

    Thyagarajan, Anita; Saylae, Jeremiah; Sahu, Ravi P

    2017-07-25

    Acquired resistance to standard therapies remains a serious challenge, requiring novel therapeutic approaches that incorporate potential factors involved in tumor resistance. As cancers including melanoma express inflammatory cyclooxygenases generating prostaglandins implicated in tumor growth, we investigated mechanism of anti-inflammatory drug, acetylsalicylic acid (ASA) which has been shown to inhibit various tumor types, however, its effects against highly aggressive melanoma model are unclear. Given our reports that an activation of platelet-activating factor-receptor (PAF-R) augments the growth and impede efficacies of therapeutic agents in experimental melanoma, we also sought to determine if PAF-R mediates anti-melanoma activity of ASA. The current studies using stably PAF-R-positive (B16-PAFR) and negative (B16-MSCV) murine melanoma cells and PAF-R-expressing and deficient mice, demonstrate that ASA inhibits the in-vitro and in-vivo growth of highly aggressive B16F10 melanoma via bypassing tumoral or stromal PAF-R signaling. Similar ASA-induced effects in-vitro were seen in human melanoma and nasopharyngeal carcinoma cells positive or negative in PAF-R. Mechanistically, the ASA-induced decrease in cell survival and increase in apoptosis were significantly blocked by prostaglandin F2 alpha (PGF2α) agonists. Importantly, PCR array and qRT-PCR analysis of B16-tumors revealed significant downregulation of sry-related high-mobility-box-2 (SOX2) oncogene by ASA treatment. Interestingly, modulation of SOX2 expression by PGF2α agonists and upregulation by fibroblast growth factor 1 (FGF-1) rescued melanoma cells from ASA-induced decreased survival and increased apoptosis. Moreover, PGF2α-receptor antagonist, AL8810 mimics ASA-induced decreased melanoma cells survival which was significantly blocked by PGF2α and FGF-1. These findings indicate that ASA inhibits the growth of aggressive melanoma via SOX2-dependent-PAF-R-indepedent pathway.

  19. Angiotensin II potentiates prostaglandin stimulation of cyclic AMP levels in intact bovine adrenal medulla cells but not adenylate cyclase in permeabilized cells.

    Science.gov (United States)

    Boarder, M R; Plevin, R; Marriott, D B

    1988-10-25

    The level of cyclic AMP in primary cultures of bovine adrenal medulla cells is elevated by prostaglandin E1. Angiotensin II is commonly reported to act on receptors linked to phosphoinositide metabolism or to inhibition of adenylate cyclase. We have investigated the effect of angiotensin II on prostaglandin E1-stimulated cyclic AMP levels in these primary cultures. Rather than reducing cyclic AMP levels, we have found that angiotensin II powerfully potentiates prostaglandin E1-stimulated cyclic AMP accumulation in intact cells, both in the presence and absence of phosphodiesterase inhibitors. The 50% maximal response was similar to that for stimulation of phosphoinositide breakdown by angiotensin II in these cultures. The potentiation of stimulated cyclic AMP levels was seen, although to a smaller maximum, with the protein kinase C (Ca2+/phospholipid-dependent enzyme) activating phorbol ester tetradecanoyl phorbolacetate and with the synthetic diacylglycerol 1-oleoyl-2-acetylglycerol; pretreatment (24 h) with active phorbol ester, which would be expected to diminish protein kinase C levels, attenuated the angiotensin II potentiation of cyclic AMP. Using digitonin-permeabilized cells we showed that adenylate cyclase activity was stimulated by prostaglandin E1 with the same dose-response relationship as was cyclic AMP accumulation in intact cells, but the permeabilized cells showed no response to angiotensin II. The results are discussed with respect to the hypothesis that the angiotensin II influence on cyclic AMP levels is mediated, in part, by diacylglycerol stimulation of protein kinase C.

  20. Effect of forskolin and prostaglandin E1 on stimulus secretion coupling in cultured bovine adrenal chromaffin cells.

    Science.gov (United States)

    Marriott, D; Adams, M; Boarder, M R

    1988-02-01

    Treatment of adrenal chromaffin cells with forskolin (0.1-10 microM) stimulated cyclic AMP levels, reduced the maximal stimulation of release of noradrenaline by nicotine, and increased release in response to elevated external potassium and the calcium ionophore A23187. The presence of the phosphodiesterase inhibitor Ro 20-17-24 with forskolin potentiated both the stimulation of cyclic AMP and the inhibition of nicotine-induced noradrenaline release. Dibutyryl cyclic AMP, and the elevation of cyclic AMP with prostaglandin E1, also attenuated nicotine-stimulated release. However, when the stimulation of intracellular cyclic AMP production by prostaglandin E1 was potentiated by low levels of forskolin, there was not a concomitant potentiation of effect on noradrenaline release. Dideoxyforskolin, an analogue of forskolin which does not stimulate adenylate cyclase, inhibited both potassium- and nicotine-stimulated release, probably by a mechanism unrelated to the action of forskolin in these experiments. Using Fura-2 to estimate free intracellular calcium levels, both forskolin and dideoxyforskolin (at 10 microM) reduced the calcium transient in response to nicotine. These results support a model in which elevation of cyclic AMP inhibits the activation of nicotinic receptors, but augments stimulus secretion coupling downstream of calcium entry. The data, however, do not indicate a simple relationship between total intracellular cyclic AMP levels and the attenuation of nicotinic stimulation of release.

  1. Expression of microsomal prostaglandin E synthase in bovine endometrium: coexpression with cyclooxygenase type 2 and regulation by interferon-tau.

    Science.gov (United States)

    Parent, Julie; Chapdelaine, Pierre; Sirois, Jean; Fortier, Michel A

    2002-08-01

    Prostaglandins (PGs) are important regulators of reproductive functions. In ruminants, interferon (IFN)-tau is the embryonic signal responsible for recognition of pregnancy. This is effected by a reduction of the production of PGF(2alpha) relative to PGE(2.) This may be accomplished by a decrease in PGF(2alpha) production, but a stimulation of PGE(2) via the PGE synthase might also be involved. The purpose of the present study was to confirm the presence of PGE synthase (PGES) in the bovine endometrium, identify the factors affecting its expression, and compare it with that of cyclooxygenase-2 (COX-2). This was done by Northern blot analysis using primary cultures of bovine epithelial and stromal cells of the endometrium and bovine endometrial cell line. PGES mRNA expression was increased in the presence of lipopolysaccharides, TNF-alpha, and IFN-tau in stromal cells and IFN-tau in epithelial cells. In stromal cells, IFN-tau induced a rapid increase of PGES and COX-2 mRNA expression. In bovine endometrial cells, phorbol 12-myristate 13-actetate increased PGES mRNA, COX-2 mRNA and PGE(2) production. These results suggest that in endometrial cells, the expression of PGE synthase is correlated with that of COX-2 and is an important enzyme for the production of PGE(2). Increasing this production will modulate the PGE(2)/PGF(2alpha) ratio and contribute to establishment of pregnancy.

  2. Interferon-alpha signalling in bovine adrenal chromaffin cells: involvement of signal-transducer and activator of transcription 1 and 2, extracellular signal-regulated protein kinases 1/2 and serine 31 phosphorylation of tyrosine hydroxylase.

    Science.gov (United States)

    Douglas, S A; Bunn, S J

    2009-03-01

    Adrenal medullary chromaffin cells are an integral part of the neuroendocrine system, playing an important role in the physiological adaptation to stress. In response to a wide variety of stimuli, including acetylcholine released from the splanchnic nerve, hormones such as angiotensin II or paracrine signals such as prostaglandins, chromaffin cells synthesise and secrete catecholamines and a number of biologically active peptides. This adrenal medullary output mediates a complex and diverse stress response. We report that chromaffin cells also respond both acutely and chronically to interferon (IFN)-alpha, thus providing a mechanism of interaction between the immune system and the stress response. Incubation of isolated bovine chromaffin cells maintained in culture, with IFN-alpha resulted in a rapid, transient activation of the extracellular signal-regulated protein kinase (ERK)1/2, which was maximal after 5 min. IFN-alpha mediated activation of ERK1/2 appeared to be responsible for the increased phosphorylation of tyrosine hydroxylase, the rate-limiting enzyme in catecholamine synthesis. This tyrosine hydroxylase phosphorylation was exclusively on serine 31, with no change in the phosphorylation of serine 19 or 40. This increase in the serine 31 phosphorylation of tyrosine hydroxylase was prevented by inhibition of protein kinase C or ERK1/2 activation. Incubation with IFN-alpha also resulted in a time- and concentration-dependent phosphorylation and nuclear translocation of signal transducer and activator of transcription proteins (STAT)1 and 2. This response was maximal after approximately 60 min. Prolonged treatment with IFN-alpha (12-48 h) resulted in increased expression of STAT1 and, to a lesser extent, STAT2. Thus, these findings demonstrate that adrenal medullary chromaffin cells are responsive to IFN-alpha and provide a possible cellular mechanism by which this immune-derived signal can potentially influence and integrate with the stress response.

  3. Prostaglandin E receptor subtype EP4 agonist serves better to protect cochlea than prostaglandin E1.

    Science.gov (United States)

    Hori, Ryusuke; Nakagawa, Takayuki; Yamamoto, Norio; Hamaguchi, Kiyomi; Ito, Juichi

    2013-12-01

    The present study aimed to examine whether an E-prostanoid receptor 4 (EP4) agonist has superior protective effects to those of prostaglandin E1 (PGE1) in a guinea pig model of noise trauma. Drugs were locally applied on the round window membrane of guinea pig cochleae, followed by exposure of the test animals to intense noise. Protective effects mediated by an EP4 agonist were compared with those mediated by PGE1. Auditory function was monitored by measurements of the auditory brainstem response (ABR), and histological damage was assessed by immunohistochemical analysis of cochlear specimens. Animals treated with an EP4 agonist exhibited significantly better hearing recovery than those pretreated with PGE1. Histologically, the numbers of remaining outer hair cells in cochleae treated with the EP4 agonist were significantly higher than in those treated with PGE1. The selective activation of EP4 has a stronger protective effect on cochleae against noise trauma than does the broad activation of EPs by PGE1. Copyright © 2013. Published by Elsevier Ireland Ltd.

  4. Alpha-amylase inhibition kinetics by caulerpenyne

    OpenAIRE

    CENGIZ, S.; CAVAS, L.; YURDAKOC, K.

    2010-01-01

    Many algae have important secretions which are generally used for defensive purposes. These secretions take attentions of a lot of researchers who are wondering if these metabolites can be used for medical researches or not. Among these metabolites, caulerpenyne (CYN) which is the main metabolite of Caulerpa species, have had an important place in Caulerpa researches since the results related to its determined properties such as cytotoxic, antiviral, antiproliferative and apoptotic effects ha...

  5. Sulindac Sulfide, but Not Sulindac Sulfone, Inhibits Colorectal Cancer Growth

    Directory of Open Access Journals (Sweden)

    Christopher S. Williams

    1999-06-01

    Full Text Available Sulindac sulfide, a metabolite of the nonsteroidal antiinflammatory drug (NSAID sulindac sulfoxide, is effective at reducing tumor burden in both familial adenomatous polyposis patients and in animals with colorectal cancer. Another sulindac sulfoxide metabolite, sulindac sulfone, has been reported to have antitumor properties without inhibiting cyclooxygenase activity. Here we report the effect of sulindac sulfone treatment on the growth of colorectal carcinoma cells. We observed that sulindac sulfide or sulfone treatment of HCA-7 cells led to inhibition of prostaglandin E2 production. Both sulindac sulfide and sulfone inhibited HCA-7 and HCT-116 cell growth in vitro. Sulindac sulfone had no effect on the growth of either HCA-7 or HCT-116 xenografts, whereas the sulfide derivative inhibited HCA-7 growth in vivo. Both sulindac sulfide and sulfone inhibited colon carcinoma cell growth and prostaglandin production in vitro, but sulindac sulfone had no effect on the growth of colon cancer cell xenografts in nude mice.

  6. Differential inhibition of 17alpha-hydroxylase and 17,20-lyase activities by three novel missense CYP17 mutations identified in patients with P450c17 deficiency

    NARCIS (Netherlands)

    E.L.T. van den Akker (Erica); J.W. Koper (Jan); A.L.M. Boehmer (Annemie); A.P.N. Themmen (Axel); M. Verhoef-Post (Miriam); M.A. Timmerman (Marianna); B.J. Otten (Barto); S.L.S. Drop (Stenvert); F.H. de Jong (Frank)

    2002-01-01

    textabstractThe microsomal enzyme cytochrome P450c17 is an important regulator of steroidogenesis. The enzyme has two functions: 17alpha-hydroxylase and 17,20-lyase activities. These functions determine the ability of adrenal glands and gonads to synthesize 17alpha-hydroxylated

  7. Radioimmune assay of human platelet prostaglandin synthetase

    International Nuclear Information System (INIS)

    Roth, G.J.; Machuga, E.T.

    1982-01-01

    Normal platelet function depends, in part, on platelet PG synthesis. PG synthetase (cyclo-oxygenase) catalyzes the first step in PG synthesis, the formation of PGH 2 from arachidonic acid. Inhibition of the enzyme by ASA results in an abnormality in the platelet release reaction. Patients with pparent congenital abnormalities in the enzyme have been described, and the effects have been referred to as ''aspirin-like'' defects of the platelet function. These patients lack platelet PG synthetase activity, but the actual content of PG synthetase protein in these individuals' platelets is unknown. Therefore an RIA for human platelet PG synthetase would provide new information, useful in assessing the aspirin-like defects of platelet function. An RIA for human platelet PG synthetase is described. The assay utilizes a rabbit antibody directed against the enzyme and [ 125 I]-labelled sheep PG synthetase as antigen. The human platelet enzyme is assayed by its ability to inhibit precipitation of the [ 125 I]antigen. The assay is sensitive to 1 ng of enzyme. By the immune assay, human platelets contain approximately 1200 ng of PG synethetase protein per 1.5 mg of platelet protein (approximately 10 9 platelets). This content corresponds to 10,000 enzyme molecules per platelet. The assay provides a rapid and convenient assay for the human platelet enzyme, and it can be applied to the assessment of patients with apparent platelet PG synthetase (cyclo-oxygenase) deficiency

  8. Discovery and Characterization of 2-Acylaminoimidazole Microsomal Prostaglandin E Synthase-1 Inhibitors.

    Science.gov (United States)

    Schiffler, Matthew A; Antonysamy, Stephen; Bhattachar, Shobha N; Campanale, Kristina M; Chandrasekhar, Srinivasan; Condon, Bradley; Desai, Prashant V; Fisher, Matthew J; Groshong, Christopher; Harvey, Anita; Hickey, Michael J; Hughes, Norman E; Jones, Scott A; Kim, Euibong J; Kuklish, Steven L; Luz, John G; Norman, Bryan H; Rathmell, Richard E; Rizzo, John R; Seng, Thomas W; Thibodeaux, Stefan J; Woods, Timothy A; York, Jeremy S; Yu, Xiao-Peng

    2016-01-14

    As part of a program aimed at the discovery of antinociceptive therapy for inflammatory conditions, a screening hit was found to inhibit microsomal prostaglandin E synthase-1 (mPGES-1) with an IC50 of 17.4 μM. Structural information was used to improve enzyme potency by over 1000-fold. Addition of an appropriate substituent alleviated time-dependent cytochrome P450 3A4 (CYP3A4) inhibition. Further structure-activity relationship (SAR) studies led to 8, which had desirable potency (IC50 = 12 nM in an ex vivo human whole blood (HWB) assay) and absorption, distribution, metabolism, and excretion (ADME) properties. Studies on the formulation of 8 identified 8·H3PO4 as suitable for clinical development. Omission of a lipophilic portion of the compound led to 26, a readily orally bioavailable inhibitor with potency in HWB comparable to celecoxib. Furthermore, 26 was selective for mPGES-1 inhibition versus other mechanisms in the prostanoid pathway. These factors led to the selection of 26 as a second clinical candidate.

  9. The effects of prostaglandins on the intraocular pressure of the rabbit

    Science.gov (United States)

    Beitch, Barbara R.; Eakins, K. E.

    1969-01-01

    1. The effects of intracameral injections of prostaglandins E1, E2, F1a, F2a, and A1 were studied on the intraocular pressure (IOP) of rabbits anaesthetized with urethane. 2. With the exception of prostaglandin F1a, all the prostaglandins studied were found to be capable of producing a large, sustained rise in IOP, accompanied in many cases by miosis. 3. A marked decrease in response to repeated injections was found with all the prostaglandins studied; this effect was more pronounced following a large initial response to the prostaglandin. 4. The descending order of potency in their ability to raise IOP was as follows: prostaglandin E1≈E2>F2a>A1>F1a. 5. Intracameral injections of prostaglandins E1 and E2 resulted in an increase in the protein content of the aqueous humour, which was related to the magnitude of the sustained increase in IOP. 6. Stabilization of the blood-aqueous barrier with polyphloretin phosphate markedly reduced both the IOP response and the effect of prostaglandin E2 on the protein content of the aqueous humour. 7. It is concluded that the production of local vasodilatation and increased permeability of the blood-aqueous barrier play an important part in the effect of prostaglandins on the IOP. The involvement of prostaglandins in the response of the rabbit eye to irritation is discussed. PMID:4981000

  10. Butyrate attenuates lipolysis in adipocytes co-cultured with macrophages through non-prostaglandin E2-mediated and prostaglandin E2-mediated pathways.

    Science.gov (United States)

    Ohira, Hideo; Tsutsui, Wao; Mamoto, Rie; Yamaguchi, Sayaka; Nishida, Masako; Ito, Miki; Fujioka, Yoshio

    2016-12-09

    Interactions between adipocytes and macrophages are associated with metabolic disorders. Production of pro-inflammatory mediators and the release of free fatty acids (FFAs) increase when these cells are co-cultured; butyrate significantly diminishes these effects by suppressing both the macrophage inflammatory and adipocyte lipolysis pathways. Butyrate is known to up-regulate the expression of prostaglandin E2 (PGE2). Therefore, we hypothesized that PGE2 is associated with the suppression of lipolysis by butyrate in co-culture. Using contact or transwell co-culture methods with differentiated 3T3-L1 adipocytes and RAW264.7 macrophages, we investigated the effects of butyrate on the release of PGE2 into the medium and on lipolysis in adipocytes. To elucidate the underlying mechanism, we examined the effects of butyrate on cyclooxygenase-2 (COX2) and phospholipase A2 (PLA2) in co-cultured cells, and cyclic adenine monophosphate (cAMP) and protein kinase A type 1-α regulatory subunit (PRKAR1A) in co-cultured adipocytes. Silent interfering (si)RNA targeting of G-protein-coupled receptor (GPR)41 and 109A was employed to examine the effect on lipolysis in TNF-α-stimulated adipocytes. Co-culture increased PGE2 release into the medium, compared with cells cultured separately. Butyrate significantly increased PGE2 production. Co-culture elevated COX2 expression in macrophages and adipocytes, and butyrate further enhanced this effect. Co-culture enhanced cytosolic PLA2 activity in macrophages, which was further enhanced by butyrate. As for lipolysis, co-culture increased the release of FFAs and free glycerol into the medium, whereas butyrate (and to a lesser extent, PGE2) suppressed FFAs and free glycerol release. An inhibition study using a prostaglandin E receptor 3-selective antagonist suggested that approximately 40% of the suppressive effect of butyrate depends on the PGE2-mediated pathway, whereas 60% depends on a non-PGE2-mediated pathway. Co-culture increased c

  11. Coulomb correction to elastic. alpha. -. alpha. scattering

    Energy Technology Data Exchange (ETDEWEB)

    Bera, P.K.; Jana, A.K.; Haque, N.; Talukdar, B. (Department of Physics, Visva-Bharati University, Santiniketan-731235, West Bengal, India (IN))

    1991-02-01

    The elastic {alpha}-{alpha} scattering is treated within the framework of a generalized phase-function method (GPFM). This generalization consists in absorbing the effect of Coulomb interaction in the comparison functions for developing the phase equation. Based on values of scattering phase shifts computed by the present method, it is concluded that the GPFM provides an uncomplicated approach to rigorous Coulomb correction in the {alpha}-{alpha} scattering.

  12. Intrahepatic expression of interferon alpha & interferon alpha ...

    African Journals Online (AJOL)

    kemrilib

    Alpha m-RNA while 30% only expressed Interferon Alpha Receptor m-RNA. Responders and non-responders to Interferon therapy ... expression of IFN Alpha Receptor mRNA. Regardless of the response to interferon, histological .... generation reverse hybridisation, line probe assay. (Inno-LiPA HCV II; Innogenetics, Ghent,.

  13. Prostaglandins compromise basal forebrain cholinergic neuron differentiation and survival: action at EP1/3 receptors results in AIF-induced death.

    Science.gov (United States)

    Jonakait, G Miller; Ni, Li

    2009-08-18

    Activated microglia produce a factor or cocktail of factors that promotes cholinergic neuronal differentiation of undifferentiated precursors in the embryonic basal forebrain (BF) in vitro. To determine whether microglial prostaglandins mediate this action, microglia were stimulated in the presence of the cyclooxygenase inhibitor ibuprofen, and microglial conditioned medium (CM) was used to culture rat BF precursors at embryonic day 15. Choline acetyltransferase (ChAT) activity served as a measure of cholinergic differentiation. While inhibition of prostaglandin biosynthesis did not affect the ability of microglial CM to promote ChAT activity, treatment of microglia with prostaglandin E2 (PGE2) inhibited it. Agonists of E prostanoid receptors EP2 (butaprost) and EP1/3 (sulprostone) mimicked PGE2, while misoprostol (E1-4) actually enhanced the action of CM. PGE2 added directly to BF cultures together with microglial CM also inhibited ChAT activity. While BF cultures expressed all four prostanoid receptors, direct addition of sulprostone but not butaprost mimicked PGE2, suggesting that PGE2 engaged EP1/3 receptors in the BF. Neither PKA inhibition by H89 nor cAMP induction by forskolin or dibutyrl-cAMP altered the action of sulprostone. Sulprostone severely compromised ChAT activity, dendrite number, axonal length and axonal branching, but caspase inhibition did not restore these. However, sulprostone resulted in increased staining intensity and nuclear translocation of apoptosis-inducing factor (AIF) suggesting caspase-independent cell death. We have found that PGE2 action at microglial EP2 receptors inhibits the microglial production of the cholinergic differentiating cocktail, while action at neuronal EP3 receptors has a deleterious effect on cholinergic neurons causing neurite retraction and cell death.

  14. Intracervical misoprostol and prostaglandin E2 for labor induction.

    Science.gov (United States)

    Chang, Y-K; Chen, W-H; Yu, M-H; Liu, H-S

    2003-01-01

    To compare the safety and efficacy of misoprostol with PGE(2) for induction of labor by intracervical administration. Eighty-six women with indications for labor induction at term were randomly assigned to two groups. Each woman received either 50 microg of misoprostol or 0.5 mg of prostaglandin E(2) intracervically. If labor was not initiated after 4 h, the same dose was repeated every 4 h to a maximum of 200 microg of misoprostol or 1.5 mg of PGE(2) until adequate labor was achieved. Forty-three women were allocated to the misoprostol group and 43 to the prostaglandin E(2) group. Misoprostol was more effective than PGE(2) in producing cervical changes (Pintracervical misoprostol is more effective in cervical ripening and labor induction at term. The higher frequency of uterine hypercontractility associated with the use of misoprostol did not increase the risk of adverse intrapartum and neonatal outcomes.

  15. Intra-arterial infusion of prostaglandin EI in Buerger's disease

    International Nuclear Information System (INIS)

    Kim, Yang Min; Park, Jae Hyung; Kim, Sang Joon

    1990-01-01

    In Buerger's disease, arterial occlusion is so peripheral that reopening procedure such as reconstructive vascular surgery, percutaneous transluminal angioplasty and local fibrinolysis are not feasible, and major amputation is the only alternative. Prostaglandin E1, a potent vasodilator and inhibitor of platelet aggregation, has been used to treat the patients with severe arterial occlusive disease. In three cases of Buerger's disease, who are manifested by resting pain, non-healing ischemic ulcer, or impending gangrene and who were not candidates for direct arterial reconstructive procedure, we infused Prostaglandin El intraarterially at a fixed dosage to evaluate its effectiveness. We report our experience with the use of this drug in relieving the ischemic symptoms, healing the intractable ulcer, or avoiding the major amputation

  16. Acetylsalicylic acid interferes with embryonic kidney growth and development by a prostaglandin-independent mechanism.

    Science.gov (United States)

    Welham, Simon J M; Sparrow, Alexander J; Gardner, David S; Elmes, Matthew J

    2017-01-06

    To evaluate the effects of the non-selective, non-steroidal anti-inflammatory drug (NSAID) acetylsalicylic acid (ASA), on ex vivo embryonic kidney growth and development. Pairs of fetal mouse kidneys at embryonic day 12.5 were cultured ex vivo in increasing concentrations of ASA (0.04-0.4 mg/mL) for up to 7 d. One organ from each pair was grown in control media and was used as the internal control for the experimental contralateral organ. In some experiments, organs were treated with ASA for 48 h and then transferred either to control media alone or control media containing 10 μmol/L prostaglandin E 2 (PGE 2 ) for a further 5 d. Fetal kidneys were additionally obtained from prostaglandin synthase 2 homozygous null or heterozygous (PTGS2 -/- and PTGS2 -/+ ) embryos and grown in culture. Kidney cross-sectional area was used to determine treatment effects on kidney growth. Whole-mount labelling to fluorescently detect laminin enabled crude determination of epithelial branching using confocal microscopy. Increasing ASA concentration (0.1, 0.2 and 0.4 mg/mL) significantly inhibited metanephric growth ( P < 0.05). After 7 d of culture, exposure to 0.2 mg/mL and 0.4 mg/mL reduced organ size to 53% and 23% of control organ size respectively ( P < 0.01). Addition of 10 μmol/L PGE 2 to culture media after exposure to 0.2 mg/mL ASA for 48 h resulted in a return of growth area to control levels. Application of control media alone after cessation of ASA exposure showed no benefit on kidney growth. Despite the apparent recovery of growth area with 10 μmol/L PGE 2 , no obvious renal tubular structures were formed. The number of epithelial tips generated after 48 h exposure to ASA was reduced by 40% (0.2 mg/mL; P < 0.05) and 47% (0.4 mg/mL; P < 0.01). Finally, growth of PTGS2 -/- and PTGS2 +/- kidneys in organ culture showed no differences, indicating that PTGS2 derived PGE 2 may at best have a minor role. ASA reduces early renal growth and development but the role of

  17. Prostaglandin E2 Regulation of Chondrocyte Proliferation and Differentiation

    Science.gov (United States)

    1994-05-01

    increased bone resorption in osteolytic lesions(3 ,31), periodontal disease (32-34), osteomyelitis (35), and rheumatoid arthritis (36). Stimulation of...a, and IL-18 have been shown to increase production of E-series prostaglandins in osteoblasts(4 -42), periodontal ligament fibroblasts(43,44), and...enhanced bone formation during regenerative and augmentation procedures. LITERATURE CITED 1. Raisz, L.G. and B.E. Kream. 1983. Regulation of Bone

  18. Sex differences in prostaglandin biosynthesis in neutrophils during acute inflammation

    OpenAIRE

    Pace, Simona; Rossi, Antonietta; Krauth, Verena; Dehm, Friederike; Troisi, Fabiana; Bilancia, Rossella; Weinigel, Christina; Rummler, Silke; Werz, Oliver; Sautebin, Lidia

    2017-01-01

    The severity and course of inflammatory processes differ between women and men, but the biochemical mechanisms underlying these sex differences are elusive. Prostaglandins (PG) and leukotrienes (LT) are lipid mediators linked to inflammation. We demonstrated superior LT biosynthesis in human neutrophils and monocytes, and in mouse macrophages from females, and we confirmed these sex differences in vivo where female mice produced more LTs during zymosan-induced peritonitis versus males. Here, ...

  19. Separation of prostaglandin metabolites on sephadex LH 20 columns

    DEFF Research Database (Denmark)

    Hansen, Harald S.; Bukhave, K.

    1978-01-01

    Sephadex LH 20 columns have been investigated for the separation of initial prostaglandin metabolites. Solvent systems are described for the separation of the free acids of 15-keto-dihydro-PGE, 15-keto-PGE, PGE, and PGF(1a). Further, one of the solvent systems is described for the separation...... of pulmonary metabolites of PGE and PGF(1a), and another one for separation of dihydro-PGE and PGE....

  20. Deficiency of alpha7 cholinergic receptors facilitates bacterial clearance in Escherichia coli peritonitis

    NARCIS (Netherlands)

    Giebelen, Ilona A. J.; Le Moine, Alain; van den Pangaart, Petra S.; Sadis, Claude; Goldman, Michel; Florquin, Sandrine; van der Poll, Tom

    2008-01-01

    BACKGROUND: The efferent vagus nerve can inhibit inflammation via interaction between acetylcholine and alpha7 cholinergic receptors. METHODS: To determine the role played by alpha7 receptors in antibacterial defense, peritonitis was induced in alpha7 receptor-deficient (alpha7(-/-)) and wild-type

  1. cAMP does not inhibit convulxin-induced tyrosyl-phosphorylation of human platelet proteins, including PLCgamma2, but completely blocks the integrin alphaIIb beta3-dependent dephosphorylation step: comparisons with RGDS peptide, cytochalasin D, and phenylarsine oxide.

    Science.gov (United States)

    Francischetti, I M; Carlini, C R; Guimarães, J A

    1998-06-15

    Convulxin (Cvx) isolated from Crotalus durissus terrificus venom, induces platelet aggregation, phospholipase C (PLC) activation, and tyrosyl-phosphorylation (PTP) of multiple proteins, including PLCgamma2 by a mechanism independent of integrin alphaIIb beta3. However, PTP induced by Cvx is followed by a dephosphorylation step in a platelet aggregation-dependent manner. Here we show that increasing intraplatelet content of cAMP with forskolin is associated with the inhibition of Cvx-induced platelet aggregation, ATP secretion, and inositol-phosphates production. However, the early onset of Cvx-induced PTP is not sensitive to cAMP (including PLCgamma2), and it also occurs in the presence of integrin alphaIIb beta3-antagonist (RGDS peptide, RGDS) or inhibitors of actin polymerization (cytochalasin D, CD) and tyrosine-phosphatases (phenylarsine oxide, PAO). However, forskolin, RGDS, and CD prevented the dephosphorylation step together with inhibition of platelet aggregation, whereas in the presence of phenylarsine oxide (PAO) the dephosphorylation step was replaced by an increase in the number and intensity of tyrosyl-phosphorylated proteins. Our data provide evidence to conclude that (i) cAMP inhibits platelet aggregation at a downstream site to PLCgamma2 tyrosyl-phosphorylation; (ii) Cvx-induced PTP is independent on integrin alphaIIb beta3 engagement, actin polymerization, and tyrosine-phosphatases activation; (iii) integrin alphaIIb beta3 mediates the dephosphorylation step in a platelet aggregation-dependent manner; and (iv) Cvx and collagen stimulate platelets by a similar signal transduction pathway. Copyright 1998 Academic Press.

  2. The introduction of tritium label into natural and modified prostaglandins

    International Nuclear Information System (INIS)

    Shevchenko, V.P.; Bezuglov, V.V.; Nagayev, I.Y.; Myasoedov, N.F.

    1989-01-01

    Studies on the role of the nature of both heterogeneous catalysts and the solvent on the reduction selectively of 5,6-double bonds showed that the largest yield could be obtained by using the Lindlar catalyst and ethyl acetate. The use of different isotopes of hydrogen in the protium-deuterium-tritium series markedly decreased the hydrogenation reaction rate, but the selectivity of the process practically remained unaltered. Homogeneous catalysts were also used in the production of natural tritium-labelled prostaglandins and of their fluorine and deoxy analogues. The label was introduced by selective hydrogenation in the presence of (Ph 3 P) 3 RhCl and dioxane as solvent. Different ways have been studied of tritium-label introduction into prostaglandins modified at the carboxyl group. The synthesis of similar preparations was performed either by selective dehalogenation in the presence of heterogeneous catalysts treated with quinoline or triethylamine, or by condensation of prostaglandins at the carboxyl group by tritium-labelled amino acid. (author). 4 refs.; 1 fig

  3. Interaction of prostaglandins and angiotensin II in the modulation of renal function in congestive heart failure.

    Science.gov (United States)

    Packer, M

    1988-06-01

    Despite a dramatic fall in renal blood flow, glomerular filtration rate is usually preserved in patients with congestive heart failure until the terminal stages of the disease. This maintenance of renal function appears to be achieved in part by the synthesis of two vasoactive factors within the kidney--angiotensin II and prostaglandins--which are rapidly released whenever renal perfusion is compromised or sympathetic nerve traffic to the kidneys is increased. Although these two hormonal systems exert opposite effects on systemic and renal blood flow and sodium and water excretion, both act to preserve glomerular filtration rate: prostaglandins by a vasodilator action exerted primarily on the afferent arteriole and angiotensin II by a vasoconstrictor effect on the efferent arteriole. Consequently, when the synthesis of these hormones is experimentally blocked, renal function deteriorates, especially in subjects with marked renal hypoperfusion and sodium depletion; these two factors interact to determine the importance of intrarenal hormonal release in the modulation of renal function. Clinically, four specific factors have been identified that predispose patients with heart failure to the development of functional renal insufficiency after treatment with converting-enzyme or cyclo-oxygenase inhibitors: (1) marked renal hypoperfusion, (2) vigorous diuretic therapy, (3) diabetes mellitus, and (4) intensity of hormonal inhibition within the kidney. This last risk factor may provide the basis for differentiating among enzyme-inhibitory drugs and suggests that renal insufficiency in low-output states may be minimized by the development of therapeutic agents that block hormonal synthesis selectively at sites that are critical to the disease process but spare the homeostatic tissue-based enzyme systems that exist within the kidney.

  4. Decreased Prostaglandin D2 Levels in Major Depressive Disorder Are Associated with Depression-Like Behaviors.

    Science.gov (United States)

    Chu, Cuilin; Wei, Hui; Zhu, Wanwan; Shen, Yan; Xu, Qi

    2017-09-01

    Prostaglandin (PG) D2 is the most abundant prostaglandin in the mammalian brain. The physiological and pharmacological actions of PGD2 in the central nervous system seem to be associated with some of the symptoms exhibited by patients with major depressive disorder. Previous studies have found that PGD2 synthase was decreased in the cerebrospinal fluid of major depressive disorder patients. We speculated that there may be a dysregulation of PGD2 levels in major depressive disorder. Ultra-performance liquid chromatography-tandem mass spectrometry coupled with a stable isotopic-labeled internal standard was used to determine PGD2 levels in the plasma of major depressive disorder patients and in the brains of depressive mice. A total of 32 drug-free major depressive disorder patients and 30 healthy controls were recruited. An animal model of depression was constructed by exposing mice to 5 weeks of chronic unpredictable mild stress. To explore the role of PGD2 in major depressive disorder, selenium tetrachloride was administered to simulate the change in PGD2 levels in mice. Mice exposed to chronic unpredictable mild stress exhibited depression-like behaviors, as indicated by reduced sucrose preference and increased immobility time in the forced swimming test. PGD2 levels in the plasma of major depressive disorder patients and in the brains of depressive mice were both decreased compared with their corresponding controls. Further inhibiting PGD2 production in mice resulted in an increased immobility time in the forced swimming test that could be reversed by imipramine. Decreased PGD2 levels in major depressive disorder are associated with depression-like behaviors. © The Author 2017. Published by Oxford University Press on behalf of CINP.

  5. Prostaglandin E1 causes sedation and increases 5-hydroxytryptamine turnover in rat brain

    Science.gov (United States)

    Haubrich, D. R.; Perez-Cruet, J.; Reid, W. D.

    1973-01-01

    1. Administration of prostaglandin E1 (1 mg/kg, i.p.) to rats induced sedation and a decrease in muscular tone. Prostaglandin E1-induced sedation was accompanied by the low voltage-high frequency E.E.G. pattern characteristic of the waking animal. 2. Administration of prostaglandin E1 also increased the turnover rate of 5-hydroxytryptamine and raised the concentration of acetylcholine in brain. 3. The behavioural effects of prostaglandin were blocked by prior administration of p-chlorophenylalanine or pargyline, drugs which lowered the brain concentration of 5-hydroxyindoleacetic acid (5-HIAA), and was potentiated by pretreatment with probenecid, which elevated the 5-HIAA concentration. Pretreatment with atropine sulphate failed to alter prostaglandin E1-induced sedation. 4. The results are compatible with the possibility that prostaglandin E1 induces a state resembling paradoxical sleep through an action on 5-hydroxytryptamine metabolism in brain. PMID:4269288

  6. Ionomycin induces prostaglandin E2 formation in murine osteoblastic MC3T3-E1 cells via mechanisms independent of its ionophoric nature.

    Science.gov (United States)

    Leis, Hans Jörg; Windischhofer, Werner

    2016-06-01

    Ionomycin and A23187 are divalent cation ionophores with a marked preference for calcium. Studies using these ionophores have almost exclusively interpreted their results in the light of calcium elevation. It was the aim of this study to investigate the effects of ionomycin in osteoblatic MC3T3-E1 cells that are not attributable to its ionophoric properties. Thus, we have found that in contrast to A23187, ionomycin shows similar effects on prostaglandin E2 formation as bradykinin and endothelin-1, being potentiated by extracellular nickel and inhibited by cholera toxin and pertussis toxin. Our data strongly suggest that inomycin, at least in part, exerts its effects via specific binding to a G-protein coupled receptor, thereby evoking downstream cellular events like arachidonate release with subsequent prostaglandin formation.

  7. [Effect of treatment with enalapril maleate on the levels of circulating catecholamines, beta endorphins, prostaglandins, and concentration of sodium in erythrocytes in patients with essential hypertension].

    Science.gov (United States)

    Chodakowska, J; Wocial, B; Ignatowska-Switalska, H; Knypl, K; Brym, E; Czerniewska, E; Wacławek-Maczkowska, J; Jabłońska-Skwiecińska, E; Drygieniec, D; Januszewicz, W

    An effect of enalapril maleate on the activity of renin-angiotensin-aldosterone system and sympathetic reactivity, erythrocyte prostaglandin and sodium levels as well as blood beta-endorphin was investigated in 28 patients with the essential arterial blood hypertension. It was found that enalapril maleate significantly increased plasma renin activity, decreased plasma norepinephrine and its 24-hour excretion, and decreased erythrocyte beta-endorphin and sodium levels. Blood epinephrine and aldosterone levels and their daily excretion remained unchanged similarly to prostaglandins. The above results suggest that a decrease in sympathetic system activity and intracellular sodium concentration may play a role in the hypotensive action of enalapril maleate related to the inhibition of angiotensin II formation.

  8. Recombinant Newcastle disease virus rL-RVG enhances the apoptosis and inhibits the migration of A549 lung adenocarcinoma cells via regulating alpha 7 nicotinic acetylcholine receptors in vitro.

    Science.gov (United States)

    Yan, Yulan; Su, Chunxiang; Hang, Min; Huang, Hua; Zhao, Yinghai; Shao, Xiaomei; Bu, Xuefeng

    2017-10-03

    The aim of this study were to investigate the possible pro-apoptotic mechanisms of the recombinant Newcastle disease virus (NDV) strain rL-RVG, which expresses the rabies virus glycoprotein, in A549 lung adenocarcinoma cells via the regulation of alpha 7 nicotinic acetylcholine receptors (α7 nAChRs) and to analyze the relationships between α7 nAChR expression in lung cancer and the clinical pathological features. α7 nAChR expression in A549, LΑ795, and small-cell lung carcinoma (SCLC) cells, among others, was detected using reverse transcription polymerase chain reaction (RT-PCR). The optimal α7 nAChR antagonist and agonist concentrations for affecting A549 lung adenocarcinoma cells were detected using MTT assays. The α7 nAChR expression in A549 cells after various treatments was assessed by Western blot, immunofluorescence and RT-PCR analyses. Apoptosis in the various groups was also monitored by Western blot and TUNEL assays, followed by the detection of cell migration via transwell and scratch tests. Furthermore, α7 nAChR expression was examined by immunohistochemistry in lung cancer tissue samples from 130 patients and 40 pericancerous tissue samples, and the apoptotis in lung adenocarcinoma tissue was detected by Tunel assay, Then, the expression levels and clinicopathological characteristics were analyzed. Of the A549, LΑ795, SCLC and U251 cell lines, the A549 cells exhibited the highest α7 nAChR expression. The cells infected with rL-RVG exhibited high RVG gene and protein expression. The rL-RVG group exhibited weaker α7 nAChR expression compared with the methyllycaconitine citrate hydrate (MLA, an α7 nAChR antagonist) and NDV groups. At the same time, the MLA and rL-RVG treatments significantly inhibited proliferation and migration and promoted apoptosis in the lung cancer cells (P A549 lung adenocarcinoma cells by regulating α7 nAChR signaling pathways.

  9. The MC160 Protein Expressed by the Dermatotropic Poxvirus Molluscum Contagiosum Virus Prevents Tumor Necrosis Factor Alpha-Induced NF-κB Activation via Inhibition of I Kappa Kinase Complex Formation

    Science.gov (United States)

    Nichols, Daniel Brian; Shisler, Joanna L.

    2006-01-01

    The pluripotent cytokine tumor necrosis factor alpha (TNF-α) binds to its cognate TNF receptor I (TNF-RI) to stimulate inflammation via activation of the NF-κB transcription factor. To prevent the detrimental effects of TNF-α in keratinocytes infected with the molluscum contagiosum virus (MCV), this poxvirus is expected to produce proteins that block at least one step of the TNF-RI signal transduction pathway. One such product, the MC160 protein, is predicted to interfere with this cellular response because of its homology to other proteins that regulate TNF-RI-mediated signaling. We report here that expression of MC160 molecules did significantly reduce TNF-α-mediated NF-κB activation in 293T cells, as measured by gene reporter and gel mobility shift assays. Since we observed that MC160 decreased other NF-κB activation pathways, namely those activated by receptor-interacting protein, TNF receptor-associated factor 2, NF-κB-inducing kinase, or MyD88, we hypothesized that the MC160 product interfered with I kappa kinase (IKK) activation, an event common to multiple signal transduction pathways. Indeed, MC160 protein expression was associated with a reduction in in vitro IKK kinase activity and IKK subunit phosphorylation. Further, IKK1-IKK2 interactions were not detected in MC160-expressing cells, under conditions demonstrated to induce IKK complex formation, but interactions between the MC160 protein and the major IKK subunits were undetectable. Surprisingly, MC160 expression correlated with a decrease in IKK1, but not IKK2 levels, suggesting a mechanism for MC160 disruption of IKK1-IKK2 interactions. MCV has probably retained its MC160 gene to inhibit NF-κB activation by interfering with signaling via multiple biological mediators. In the context of an MCV infection in vivo, MC160 protein expression may dampen the cellular production of proinflammatory molecules and enhance persistent infections in host keratinocytes. PMID:16378960

  10. In situ microdialysis of intramuscular prostaglandin and thromboxane in contracting skeletal muscle in humans

    DEFF Research Database (Denmark)

    Karamouzis, M; Langberg, Henning; Skovgaard, D

    2001-01-01

    Arachidonic acid metabolites, especially prostacyclin I2, are regulators of vascular tone, and may be released from contracting muscle. In the present study, the influence of exercise on accumulation of prostaglandins and thromboxane in skeletal muscle was determined by the use of microdialysis...... amounts of prostaglandins and thromboxanes in the interstitial space of skeletal muscle. Furthermore, the concentration of prostaglandin E2 is unchanged during static calf exercise and increased markedly with dynamic thigh muscle exercise, which together with an exercise induced increase in muscle blood...... flow indicate, that prostaglandin E2 is released from skeletal muscle during exercise in humans....

  11. Prostaglandin E/sub 2/ localization and receptor identification within the developing murine secondary palate

    Energy Technology Data Exchange (ETDEWEB)

    Jones, J.

    1986-01-01

    Transient elevations in murine secondary palatal adenosine 3',5'-monophosphate (cAMP) levels occur during palate ontogeny. Since palatal processes exposed to dibutyryl cAMP differentiate precociously, increases in palatal cAMP levels are of interest. Prostaglandin E/sub 2/ (PGE/sub 2/), which is synthesized by murine embryonic palate mesenchyme cells (MEPM), regulates cAMP levels in adult tissues via specific membrane bound receptors coupled to adenylate cyclase. Therefore, a PGE/sub 2/ receptor-adenylate cyclase systems was proposed in the developing murine secondary palate. Utilizing a radioligand binding assay, it was determined that murine palatal tissue on day 13 of gestation contained PGE/sub 2/ receptors that were saturable, of high affinity and low capacity. Specific (/sup 3/H)-PGE/sub 2/ binding was reversible by 30 min. The order of prostanoid binding affinity at specific PGE/sub 2/ binding sites was E/sub 2/ > F/sub 2//sub ..cap alpha../ > A/sub 2/ > E/sub 1/ = D/sub 2/ indicating specificity of the receptor for PGE/sub 2/. The ability of MEPM cells to respond to PGE/sub 2/ with dose-dependent accumulations of intracellular cAMP demonstrated the functional nature of these binding sites. Analysis of palatal PGE/sub 2/ receptor characteristics on days 12 and 14 of palate development indicated temporal alterations in receptor affinity and density during palate ontogeny.

  12. Effect of PEEP ventilation on renal function, plasma renin, aldosterone, neurophysins and urinary ADH, and prostaglandins.

    Science.gov (United States)

    Annat, G; Viale, J P; Bui Xuan, B; Hadj Aissa, O; Benzoni, D; Vincent, M; Gharib, C; Motin, J

    1983-02-01

    To explore the main factors which could be involved in the fluid retention induced by continuous positive pressure ventilation (CPPV), hemodynamics, renal, and hormonal parameters were measured in seven intensive care patients during three consecutive 60-min periods; one of intermittent positive pressure ventilation (IPPV), one of CPPV (PEEP 10 cmH2O), and finally one of IPPV. During CPPV, a 15% decrease in cardiac output was observed, without alteration in arterial pressure or right atrial transmural pressure. In addition, decreases were observed in urinary output by 34%, glomerular filtration rate by 19%, renal blood flow by 32%, sodium excretion by 33%, and potassium excretion by 26%. There was no change in the fractional excretion of sodium and free water. Institution of PEEP also led to a significant increase in plasma renin activity, plasma aldosterone, and urinary antidiuretic hormone, without significant variation in plasma neurophysins and urinary prostaglandins E and F alpha. All of the changes that occurred during CPPV were reversed when PEEP was withdrawn. It is concluded that the short-term antidiuretic effect of PEEP is mainly due to a hemodynamic impairment of renal function. The water- and sodium-retaining hormonal systems also are stimulated and could participate in the fluid retention during more prolonged respiratory support with PEEP.

  13. Ureaplasma diversum infection in vitro alters prostaglandin E2 and prostaglandin F2a production by bovine endometrial cells without affecting cell viability.

    Science.gov (United States)

    Kim, J J; Quinn, P A; Fortier, M A

    1994-05-01

    Bovine epithelial and stromal cells of the endometrium were inoculated with Ureaplasma diversum, pathogenic strain 2312, at 10(6) or 10(3) color-changing units (ccu)/ml in the presence of 1% fetal bovine serum (depleted of steroids by dextran-charcoal treatment) to assess the effect of infection on prostaglandin biosynthesis. When the inoculum of U. diversum was 10(6) ccu/ml, the concentration of U. diversum in the culture medium decreased with time. U. diversum was found on the epithelial and stromal cell monolayers, increasing in titer 100-fold, indicating that attachment and eventually growth occurred. When the inoculum was 10(3) ccu/ml, the titer of U. diversum remained the same or increased in the supernatant and increased on epithelial and stromal cells. The effect of infection was evaluated by measurement of the primary prostaglandin produced by each cell type, prostaglandin F2a for epithelial cells and prostaglandin E2 for stromal cells. Infection with U. diversum significantly decreased prostaglandin F2a accumulation, by 44.7% +/- 6.0% at 10(6) ccu/ml (P diversum can alter prostaglandin E2 and prostaglandin F2a patterns in primary cultures of bovine endometrial cells without affecting cell viability.

  14. Alpha 1-adrenoceptor subtypes in the rat ventricular muscle.

    Science.gov (United States)

    Kinami, J; Tsuchihashi, H; Baba, S; Mano, F; Maruyama, K; Nagatomo, T

    1992-02-01

    Scatchard analyses of [3H]prazosin binding in rat ventricular muscle membranes showed biphasic curves, which identified alpha 1High- and alpha 1Low-affinity sites. The alpha 1High-affinity site was completely inhibited by 1 microM phenoxybenzamine. The displacement potencies of alpha 1-adrenergic antagonists were characterized by [3H]prazosin binding to alpha 1High- and alpha 1Low-affinity sites in the absence and presence of 1 microM phenoxybenzamine. The affinities of most chemicals for alpha 1Low-affinity sites were significantly lower than those for alpha 1High-affinity sites, but WB-4101 (2-(2,6-dimethoxy-phenoxyethyl)aminomethyl-1,4-benzodioxane), arotinolol, cinanserin, nifedipine, and p-aminoclonidine had the same affinities for both alpha 1Low- and alpha 1High-affinity sites. These results show that two alpha 1-adrenoceptor subtypes, alpha 1High- and alpha 1Low-affinity, are present in the rat heart, and that there are physical variations in alpha 1-adrenoceptor binding sites, based on their selectivity to antagonists.

  15. Effect of probenecid on breathing movements and cerebral clearance of prostaglandin E2 in fetal sheep

    Science.gov (United States)

    Walker, David W; Pratt, Naomi

    1998-01-01

    Intravenous infusion of probencid (79-160 mg kg−1) into unanaesthetized fetal sheep (127-143 days gestation) in utero significantly decreased the incidence and amplitude of spontaneous breathing movements, but did not change the incidence of low voltage electrocortical (ECoG) activity, plasma prostaglandin E2 (PGE2) concentrations, blood gases or pH. In fetuses pretreated with paracetamol (350 mg kg−1) to inhibit PG synthase activity, infusion of probenecid did not change the mean incidence or amplitude of breathing movements, indicating that the inhibitory effect of probenecid on breathing movements required the presence of active PG synthesis. Probenecid infusion in four unanaesthetized fetuses significantly increased the PGE2 concentrations in cisternal cerebrospinal fluid (CSF) by 6.6 ± 1.5-fold (P probenecid infusion decreased the clearance of [3H]PGE2 from CSF during ventriculo-cisternal perfusion of artificial CSF containing [3H]PGE2. These results suggest that there is active transport of PGs from CSF to blood in fetal sheep from at least 127 days gestation. Inhibition of this transport results in the accumulation of PGs within interstitial fluid of the brain, one effect of which is to suppress the spontaneous activity of the respiratory centres. PMID:9481686

  16. Evaluation of some Samoan and Peruvian medicinal plants by prostaglandin biosynthesis and rat ear oedema assays.

    Science.gov (United States)

    Dunstan, C A; Noreen, Y; Serrano, G; Cox, P A; Perera, P; Bohlin, L

    1997-06-01

    In our ongoing program to find new anti-inflammatory compounds, 58 extracts from 46 different medicinal plant species, used in treatment of inflammatory disorders-38 plants from the traditional medicine of Western Samoa and eight originating from the indigenous medicine of the Shipibo-Conibo tribe of Peruvian Amazonia-ere evaluated. The ability of all extracts to inhibit cyclooxygenase-1 catalysed prostaglandin biosynthesis in vitro was examined. Of the plant species tested 14 showed moderate to strong inhibition; including 11 Samoan and three Peruvian species. Further, 12 Samoan and all eight Peruvian species were investigated on their inhibitory activity of ethyl phenylpropiolate induced rat ear oedema in vivo. Significant activity was shown by 10 of the Samoan and by all eight Peruvian species. An additional evaluation of the most active species was provided through a compilation of existing literature documenting traditional medicinal uses, pharmacological activity and chemical constituents. Several known cyclooxygenase-1 inhibitors were reported to which the observed pharmacological activity can be attributed at least partly. The combination of chemical and pharmacological literature data and our experimental data may help to explain the anti-inflammatory use of these species in indigenous medicine.

  17. PROSTAGLANDINS AND 5-HT RESPONSE ON GASTRIC SECRETION IN ALBINO RATS

    Directory of Open Access Journals (Sweden)

    P.K. Debnath

    2015-06-01

    Full Text Available Prostaglandins (PGE1 0.1, 0.2 and 0.4 mg/kg and 5-hydroxytryptamine (5-HT 1, 2.5 and 5 mg/kg dose dependently inhibited gastric secretion in pyloric legated rats model While PGF2 ∝ 0.1, 0.4 and 1mg/kg inhibited gastric acid secretion. Methysergide in the dose 0.05 mg/kg significantly stimulated the gastric secretion. When non-inhibitory dose of PGE1 (0.1 and 5-HT (1.0 mg/kg are injected simultaneously there were potentiation of inhibitory activity on gastric secretary response on volume, acid output, chloride output and pepsin output. The inhibitory activity of both PGE1 (0.4 mg/ kg and 5-HT (5.0 mg/kg including the inhibitory potentiating activity could not be modified by the pretreatment of methysergide (0.05 mg/kg. Similarly stimulatory dose of PGF2 ∝ (0.4 mg/kg and inhibitory dose of PGE1 (0.4 mg/kg administered together inhibitory response of PGE1 (0.4 mg/kg were also not modified by methysergide pretreatment.

  18. Prostaglandin H synthase-mediated bioactivation of the amino acid pyrolysate product Trp P-2

    Energy Technology Data Exchange (ETDEWEB)

    Petry, T.W.; Krauss, R.S.; Eling, T.E.

    1986-08-01

    We report evidence that the mutagen and carcinogen 3-amino-1-methyl-5H pyrido(4,3b)indole (Trp P-2) is a substrate for co-oxidation by prostaglandin H synthase (PHS) in ram seminal vesicle (RSV) microsomes. Trp P-2 serves as a reducing cofactor for the hydroperoxidase activity of PHS as shown by the concentration-dependent inhibition of the hydroperoxidase catalyzed incorporation of molecular oxygen into phenylbutazone. Spectral data suggest that this metabolism results in disruption of the double bond conjugation within the nucleus of the molecule. A single metabolite peak which was dependent upon arachidonic acid and substrate concentration was separated from the parent compound by h.p.l.c. following incubation with RSV microsomes. Co-oxidation of Trp P-2 produced reactive intermediates which bound covalently to microsomal protein (9 nmol/mg) and to calf thymus DNA (475 pmol/mg). Binding was inhibited by indomethacin, and supported by substitution of hydrogen peroxide for arachidonic acid. These data suggest a possible role for PHS in the in situ activation of Trp P-2 to its ultimate carcinogenic form in tissues which contain PHS.

  19. Relation between acid back-diffusion and luminal surface hydrophobicity in canine gastric mucosa: Effects of salicylate and prostaglandin

    International Nuclear Information System (INIS)

    Goddard, P.J.

    1989-01-01

    The stomach is thought to be protected from luminal acid by a gastric mucosal barrier that restricts the diffusion of acid into tissue. This study tested the hypothesis that the hydrophobic luminal surface of canine gastric mucosa incubated in Ussing chambers, impedes the back-diffusion of luminal acid into the tissue. Isolated sheets of mucosa were treated with cimetidine to inhibit spontaneous acid secretion, and incubated under conditions that prevented significant secretion of luminal bicarbonate. By measuring acid loss from the luminal compartment using the pH-stat technique, acid back-diffusion was continuously monitored; potential difference (PD) was measured as an index of tissue viability. Tissue luminal surface hydrophobicity was estimated by contact angle analysis at the end of each experiment. Addition of 16,16-dimethyl prostaglandin E 2 to the nutrient compartment enhanced luminal surface hydrophobicity, but did not reduce acid back-diffusion in tissues that maintained a constant PD. 10 mM salicylate at pH 4.00 in the luminal compartment reduced surface hydrophobicity, but this decrease did not occur if 1 ug/ml prostaglandin was present in the nutrient solution. Despite possessing relatively hydrophilic and relatively hydrophobic surface properties, respectively, acid back-diffusion in the absence of salicylate was not significantly different between these two groups. Neither group maintained a PD after incubation with salicylate. Lastly, radiolabeled salicylate was used to calculate the free (non-salicylate associated) acid loss in tissues incubated with salicylate and/or prostaglandin. No significant correlation was found between free acid back-diffusion and luminal surface hydrophobicity. These data do not support the hypothesis that acid back-diffusion in impeded by the hydrophobic surface presented by isolated canine gastric mucosa

  20. Conditioning of alpha bearing wastes

    International Nuclear Information System (INIS)

    1991-01-01

    Alpha bearing wastes are generated during the reprocessing of spent fuel, mixed oxide fuel fabrication, decommissioning and other activities. The safe and effective management of these wastes is of particular importance owing to the radiotoxicity and long lived characteristics of certain transuranic (TRU) elements. The management of alpha bearing wastes involves a number of stages which include collection, characterization, segregation, treatment, conditioning, transport, storage and disposal. This report describes the currently available matrices and technologies for the conditioning of alpha wastes and relates them to their compatibility with the other stages of the waste management process. The selection of a specific immobilization process is dependent on the waste treatment state and the subsequent handling, transport, storage and disposal requirements. The overall objectives of immobilization are similar for all waste producers and processors, which are to produce: (a) Waste forms with sufficient mechanical, physical and chemical stability to satisfy all stages of handling, transport and storage (referred to as the short term requirements), and (b) Waste forms which will satisfy disposal requirements and inhibit the release of radionuclides to the biosphere (referred to as the long term requirements). Cement and bitumen processes have already been successfully applied to alpha waste conditioning on the industrial scale in many of the IAEA Member States. Cement systems based on BFS and pozzolanic cements have emerged as the principal encapsulation matrices for the full range of alpha bearing wastes. Alternative technologies, such as polymers and ceramics, are being developed for specific waste streams but are unlikely to meet widespread application owing to cost and process complexity. The merits of alpha waste conditioning are improved performance in transport, storage and disposal combined with enhanced public perception of waste management operations. These

  1. Dietary perilla oil inhibits proinflammatory cytokine production in the bronchoalveolar lavage fluid of ovalbumin-challenged mice.

    Science.gov (United States)

    Chang, Hui-Hsiang; Chen, Chin-Shun; Lin, Jin-Yuarn

    2008-06-01

    To evaluate the anti-inflammatory effects of different dietary oils on ovalbumin-sensitized and -challenged mice. Experimental BALB/c mice were fed with different diets containing 5% corn oil [rich in linoleic acid, 18:2n-6 polyunsaturated fatty acids (PUFA), as a control diet], 5% perilla oil (rich in alpha-linolenic acid, 18:3n-3 PUFA) or 5% compound oil containing 50% corn oil and 50% perilla oil, for 5 consecutive weeks. The leukocyte count, inflammatory mediators, and cytokine levels, including proinflammatory and Th1/Th2 cytokines in the bronchoalveolar lavage fluid (BALF) from the mice were determined. The results showed that 5% compound oil administration significantly (P 0.05) decrease the eosinophil accumulation or the secretions of inflammatory mediators such as prostaglandin E2 (PGE2), histamine, nitric oxide and eotaxin. However, dietary perilla oil significantly (P < 0.05) reduced proinflammatory cytokine (TNF-alpha, IL-1beta and IL-6) and Th1 cytokine (IFN-gamma and IL-2) production. The production of Th2 cytokine IL-10, but not IL-4 and IL-5, was also significantly inhibited by perilla oil administration. The results suggest that dietary perilla oil might alleviate inflammation via decreasing the secretion of pro-inflammatory cytokines in BALF, but failed to regulate the Th1/Th2 balance toward Th1 pole during the Th2-skewed allergic airway inflammation.

  2. Opposing actions of the progesterone metabolites, 5alpha-dihydroprogesterone (5alphaP) and 3alpha-dihydroprogesterone (3alphaHP) on mitosis, apoptosis, and expression of Bcl-2, Bax and p21 in human breast cell lines.

    Science.gov (United States)

    Wiebe, John P; Beausoleil, Michel; Zhang, Guihua; Cialacu, Valentin

    2010-01-01

    Previous studies have shown that breast tissues and breast cell lines convert progesterone (P) to 5alpha-dihydroprogesterone (5alphaP) and 3alpha-dihydroprogesterone (3alphaHP) and that 3alphaHP suppresses, whereas 5alphaP promotes, cell proliferation and detachment. The objectives of the current studies were to determine if the 5alphaP- and 3alphaHP-induced changes in cell numbers are due to altered rates of mitosis and/or apoptosis, and if 3alphaHP and 5alphaP act on tumorigenic and non-tumorigenic cells, regardless of estrogen (E) and P receptor status. The studies were conducted on tumorigenic (MCF-7, MDA-MB-231, T47D) and non-tumorigenic (MCF-10A) human breast cell lines, employing several methods to assess the effects of the hormones on cell proliferation, mitosis, apoptosis and expression of Bcl-2, Bax and p21. In all four cell lines, 5alphaP increased, whereas 3alphaHP decreased cell numbers, [(3)H]thymidine uptake and mitotic index. Apoptosis was stimulated by 3alphaHP and suppressed by 5alphaP. 5alphaP resulted in increases in Bcl-2/Bax ratio, indicating decreased apoptosis; 3alphaHP resulted in decreases in Bcl-2/Bax ratio, indicating increased apoptosis. The effects of either 3alphaHP or 5alphaP on cell numbers, [(3)H]thymidine uptake, mitosis, apoptosis, and Bcl-2/Bax ratio, were abrogated when cells were treated simultaneously with both hormones. The expression of p21 was increased by 3alphaHP, and was unaffected by 5alphaP. The results provide the first evidence that 5alphaP stimulates mitosis and suppresses apoptosis, whereas 3alphaHP inhibits mitosis and stimulates apoptosis. The opposing effects of 5alphaP and 3alphaHP were observed in all four breast cell lines examined and the data suggest that all breast cancers (estrogen-responsive and unresponsive) might be suppressed by blocking 5alphaP formation and/or increasing 3alphaHP. The findings further support the hypothesis that progesterone metabolites are key regulatory hormones and that changes

  3. Prostaglandin-associated periorbitopathy in latanoprost users

    Directory of Open Access Journals (Sweden)

    Nakakura S

    2014-12-01

    Full Text Available Shunsuke Nakakura,1 Minamai Yamamoto,1 Etsuko Terao,1 Nozomi Nagatomi,1 Naoko Matsuo,1 Yausko Fujisawa,1 Yuki Fujio,1 Hitoshi Tabuchi,1 Yoshiaki Kiuchi2 1Department of Ophthalmology, Saneikai Tsukazaki Hospital, Himeji, Japan; 2Department of Ophthalmology and Visual Sciences, Graduate School of Biomedical Sciences, Hiroshima University, Hiroshima, Japan Purpose: We investigated the incidence of prostaglandin-associated periorbitopathy (PAP in subjects with glaucoma treated with latanoprost ophthalmic solution.Subjects and methods: One eye and the forehead in 22 subjects were evaluated. All patients had used latanoprost for more than 1 year (range, 12 to 45 months; mean, 26.0 months and were prostaglandin F2α analogue treatment-naïve. Digital photographs of the subjects obtained before latanoprost therapy and at the last examination were compared retrospectively. Four signs of PAP (deepening of the upper eyelid sulcus (DUES, upper eyelid ptosis, flattening of the lower eyelid bags, and inferior scleral show and supplemental side effects around the eyelids (eyelash growth, poliosis, and eyelid pigmentation were judged to be negative or positive by three independent observers. If the observers unanimously rated a sign as positive, the result was defined as positive.Results: Twelve subjects (54.5% had no apparent signs. Three subjects were judged to have DUES (13.6%, and two subjects each were judged to have flattening of the lower eyelid bags and eyelid pigmentation (9.0%. The other signs were judged as positive in only one subject each, respectively (4.5%. A univariate logistic regression analysis showed no significant associations between any of the signs and age, sex, or the duration of therapy.Conclusion: Latanoprost induced DUES, upper eyelid ptosis, flattening of the lower eyelid bags, inferior scleral show, and supplemental side effects around the eyelids; however, the rates of such occurrence might be relatively low. Keywords: glaucoma

  4. Expression of prostaglandin synthases (pgds and pges) duringzebrafishgonadal differentiation

    DEFF Research Database (Denmark)

    Jørgensen, Anne; Nielsen, John E.; Nielsen, Betina F.

    2010-01-01

    The present study aimed at elucidating whether the expression pattern of the membrane bound form of prostaglandin E-2 synthase (pges) and especially the lipocalin-type prostaglandin D-2 synthase (pgds) indicates involvement in gonadal sex differentiation in zebrafish as has previously been found ...

  5. The Value of Intravenous Prostaglandin E2 after Intra-uterine Death

    African Journals Online (AJOL)

    1974-09-21

    Sep 21, 1974 ... ficantly smaller doses of prostaglandins can achieve deli- very of the fetus and an intravenous route will be the method of choice. However, in cases of rhesus iso- immunisation, where larger doses of prostaglandin are required, with correspondingly more severe side-effects, the extra-amniotic route may be ...

  6. Mifepristone in combination with prostaglandins for termination of 10-16 weeks' gestation: a systematic review

    NARCIS (Netherlands)

    Chen, Qiu-ju; Hou, Shu-ping; Meads, Catherine; Huang, Yong-mei; Hong, Qing-qing; Zhu, Hao-ping; Cheng, Li-nan; Mignini, L.; von Dadelszen, P.; Magee, L.; Sawchuck, D.; Gao, E.; Mol, B. W.; Oude Rengerink, K.; Zamora, J.; Fox, C.; Daniels, J.; Khan, K. S.; Thangaratinam, S.; Meads, C.

    2011-01-01

    Medical regimens using mifepristone in combination with prostaglandins have been widely available for women undergoing termination of pregnancy (TOP) at 10-16 weeks' gestation in China. We undertook a systematic review to compare different regimens of mifepristone with prostaglandins for TOP at

  7. The Prostaglandin E2-EP3 Receptor Axis Regulates Anaplasma phagocytophilum-Mediated NLRC4 Inflammasome Activation.

    Directory of Open Access Journals (Sweden)

    Xiaowei Wang

    2016-08-01

    Full Text Available Rickettsial agents are sensed by pattern recognition receptors but lack pathogen-associated molecular patterns commonly observed in facultative intracellular bacteria. Due to these molecular features, the order Rickettsiales can be used to uncover broader principles of bacterial immunity. Here, we used the bacterium Anaplasma phagocytophilum, the agent of human granulocytic anaplasmosis, to reveal a novel microbial surveillance system. Mechanistically, we discovered that upon A. phagocytophilum infection, cytosolic phospholipase A2 cleaves arachidonic acid from phospholipids, which is converted to the eicosanoid prostaglandin E2 (PGE2 via cyclooxygenase 2 (COX2 and the membrane associated prostaglandin E synthase-1 (mPGES-1. PGE2-EP3 receptor signaling leads to activation of the NLRC4 inflammasome and secretion of interleukin (IL-1β and IL-18. Importantly, the receptor-interacting serine/threonine-protein kinase 2 (RIPK2 was identified as a major regulator of the immune response against A. phagocytophilum. Accordingly, mice lacking COX2 were more susceptible to A. phagocytophilum, had a defect in IL-18 secretion and exhibited splenomegaly and damage to the splenic architecture. Remarkably, Salmonella-induced NLRC4 inflammasome activation was not affected by either chemical inhibition or genetic ablation of genes associated with PGE2 biosynthesis and signaling. This divergence in immune circuitry was due to reduced levels of the PGE2-EP