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Sample records for prostaglandin f2alpha regulates

  1. Prostaglandin F(2alpha) receptor in the neurohypophysis of hens.

    PubMed

    Takahashi, T; Kawashima, M

    2009-08-01

    To elucidate whether the receptor for prostaglandin (PG) F(2alpha), one of PG, exists in the neurohypophysis in hens and whether the binding of receptor changes with relation to oviposition, the PGF(2alpha) binding component in the membrane fraction of the neurohypophysis of laying hens was analyzed by radioligand binding assay using [5,6,8,9,11,12,14,15(n)-(3)H]PGF(2alpha). The binding component had characteristics of a receptor such as binding specificity, high affinity, and limited capacity for PGF(2alpha). Scatchard analysis indicated that the binding site was of a single class. The binding capacity of the receptor was smaller in laying hens than in nonlaying hens, whereas the binding affinity was not significantly different between these hens. When non-laying hens received an i.m. injection of estradiol-17beta or progesterone (0.5 mg/hen), the specific binding of the PGF(2alpha) receptor in the neurohypophysis was decreased. In laying hens, the specific binding decreased and the blood arginine vasotocin (AVT) concentration increased just after oviposition but did not change during a 24-h day in nonlaying hens. An i.v. injection of PGF(2alpha) (2 microg/hen) induced oviposition and caused an increase in the blood AVT concentration with a decrease in the specific binding of PGF(2alpha) receptor. The present study suggests a possibility that PGF(2alpha) may directly cause the AVT release from the neurohypophysis at oviposition time in hens. PMID:19590087

  2. Bimatoprost and prostaglandin F(2 alpha) selectively stimulate intracellular calcium signaling in different cat iris sphincter cells.

    PubMed

    Spada, Clayton S; Krauss, Achim H-P; Woodward, David F; Chen, June; Protzman, Charles E; Nieves, Amelia L; Wheeler, Larry A; Scott, David F; Sachs, George

    2005-01-01

    Bimatoprost is a synthetic analog of prostaglandin F(2 alpha) ethanolamide (prostamide F(2 alpha)), and shares a pharmacological profile consistent with that of the prostamides. Like prostaglandin F(2 alpha) carboxylic acid, bimatoprost potently lowers intraocular pressure in dogs, primates and humans. In order to distinguish its mechanism of action from prostaglandin F(2 alpha), fluorescence confocal microscopy was used to examine the effects of bimatoprost, prostaglandin F(2 alpha) and 17-phenyl prostaglandin F(2 alpha) on calcium signaling in resident cells of digested cat iris sphincter, a tissue which exhibits contractile responses to both agonists. Constant superfusion conditions obviated effective conversion of bimatoprost. Serial challenge with 100 nM bimatoprost and prostaglandin F(2 alpha) consistently evoked responses in different cells within the same tissue preparation, whereas prostaglandin F(2 alpha) and 17-phenyl prostaglandin F(2 alpha) elicited signaling responses in the same cells. Bimatoprost-sensitive cells were consistently re-stimulated with bimatoprost only, and prostaglandin F(2 alpha) sensitive cells could only be re-stimulated with prostaglandin F(2 alpha). The selective stimulation of different cells in the same cat iris sphincter preparation by bimatoprost and prostaglandin F(2 alpha), along with the complete absence of observed instances in which the same cells respond to both agonists, strongly suggests the involvement of distinct receptors for prostaglandin F(2 alpha) and bimatoprost. Further, prostaglandin F(2 alpha) but not bimatoprost potently stimulated calcium signaling in isolated human embryonic kidney cells stably transfected with the feline- and human-prostaglandin F(2 alpha) FP-receptor and in human dermal fibroblast cells, and only prostaglandin F(2 alpha) competed with radioligand binding in HEK-feFP cells. These studies provide further evidence for the existence of a bimatoprost-sensitive receptor that is distinct from

  3. Isoprostane 8-epi-prostaglandin F2 alpha is a potent contractor of human peripheral lymphatics.

    PubMed

    Sinzinger, H; Oguogho, A; Kaliman, J

    1997-09-01

    Isoprostanes are products of free radical-catalyzed peroxidation and 8-epi-prostaglandin (PG) F2 alpha is the most important vasomodulator of this group of compounds. In human lower leg lymphatics isolated from 5 different patients without a smoking history or hyperlipidemia, 8-epi-PGF2 alpha stimulated in vitro contraction more strongly than the thromboxane receptor agonist U46619. Other isoprostanes (8-epi-PGE1, 8-epi-PGE2) had only limited lymphatic contractile potency. These data suggest a potentially relevant role for epi-8-PGF2 alpha in facilitating lymph transport especially in conditions of inflammation. PMID:9313207

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

    SciTech Connect

    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.

  5. Rapid induction of gene expression in the corpus luteum following in vivo treatment with prostaglandin F2 alpha

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The pulsatile uterine secretion of prostaglandin F2 alpha (PGF) triggers the regression of the corpus luteum (CL). Research from many laboratories has identified the early intracellular signaling events initiated by PGF (for example, activation of phospholipases, increased intracellular calcium, an...

  6. Studies on a novel series of acyl ester prodrugs of prostaglandin F2 alpha.

    PubMed Central

    Cheng-Bennett, A; Chan, M F; Chen, G; Gac, T; Garst, M E; Gluchowski, C; Kaplan, L J; Protzman, C E; Roof, M B; Sachs, G

    1994-01-01

    A novel series of prostaglandin F2 alpha (PGF2 alpha) prodrugs, with acyl ester groups at the 9, 11, and 15 positions, was prepared in order to design clinically acceptable prostaglandins for treating glaucoma. Studies involving isolated esterases and ocular tissue homogenates indicated that 9-acyl esters cannot provide a prodrug since PGF2 alpha would not be formed as a product. In contrast, 11-mono, 15-mono, and 11, 15-diesters were converted to PGF2 alpha in ocular tissues and could, therefore, be considered as prodrugs of PGF2 alpha. Carboxylesterase (CE) appeared critically important for the hydrolytic conversion of those PGF2 alpha prodrugs where the 11 or 15-OH group was esterified and such prodrugs were not substrates for acetylcholinesterase (ACHE) or butyrylcholinesterase (BuCHE). The enzymatic hydrolysis of PGF2 alpha-1-isopropyl ester was also investigated for comparative purposes. This PGF2 alpha prodrug was a good substrate for CE, but was also hydrolysed by BuCHE, albeit at a much slower rate. The most striking feature of the enzymatic hydrolysis of PGF2 alpha-1-isopropyl ester in ocular tissue homogenates was that it was much faster than for prodrugs esterified at the 11 and/or 15 positions. In terms of ocular hypotensive activity, all prodrugs which showed detectable conversion to nascent PGF2 alpha were potent ocular hypotensives. Although no separation of ocular hypotensive and ocular surface hyperaemic effects was apparent for PGF2 alpha-1-isopropyl ester, a temporal separation of these effects was apparent for the novel PGF2 alpha ester series. This difference may reflect an unfavourably rapid conversion of PGF2 alpha-1-isopropyl ester in ocular surface tissues compared with anterior segment tissues. PMID:7918269

  7. Inhibitory effect of progesterone on the lactogenic and abortive action of prostaglandin F2alpha.

    PubMed

    Vermouth, N T; Deis, R P

    1975-07-01

    The effect of ovariectomy, progesterone and prolactin treatment on the action of prostaglandin F2alpha (PGF2alpha) was determined in pregnant rats. PGF2alpha (150 mug times 2) injected i.p. on day 1. or 18 of pregnancy induced lactogenesis about 25 h later and abortion on days 20 and 21 of pregnancy. Treatment with PGF2alpha (100 mug times 2 or 50 mug times 2) on day 19 induced lactogenesis around 22 or 38 h later, respectively, and abortion on day 21. PHF2alpha treatment on day 17 was less effective. Unilateral ovariectomy on day 17 of pregnancy induced lactogenesis 32 h later but not abortion. PGF2alpha (150 mug times 2) given on the day of surgery advanced lactogenesis 12 h and rats aborted on day 19. Bilateral overiectomy on day 17 induced abortion between days 20 to 21, but if a single dose of PGF2alpha (300 mug) was injected on day 18. all the ovariectomized rats aborted on day 19. Progesterone (10 mg) injected into rats treated with PGF2alpha (150 mug times 2) on day 18, prevented abortion and delayed lactogenesis. Prolactin (1 mg times 4) treatment delayed only abortion. Serum prolactin levels were significantly higher 12 h after the last dose of PGF2alpha (150 mug times 2) in rats treated on days 17, 18 or 19 of pregnancy. Pretreatment with progesterone prevented the rise in prolactin concentration. These result suggest that the lactogenic and abortive action of PGF2alpha may be dependent on the uterine and plasma concentration of progesterone. PMID:1165437

  8. Metabolism of prostaglandin F2 alpha in Zellweger syndrome. Peroxisomal beta-oxidation is a major importance for in vivo degradation of prostaglandins in humans.

    PubMed Central

    Diczfalusy, U; Kase, B F; Alexson, S E; Björkhem, I

    1991-01-01

    We have recently shown in vitro that the peroxisomal fraction of a rat liver homogenate has the highest capacity to beta-oxidize prostaglandins. In order to evaluate the relative importance of peroxisomes for this conversion also in vivo, we administered [3H]prostaglandin F2 alpha to an infant suffering from Zellweger syndrome, a congenital disorder characterized by the absence of intact peroxisomes. As a control, labeled compound was administered to two healthy volunteers. Urine was collected, fractionated on a SEP-PAK C18 cartridge, and subjected to reversed-phase high-performance liquid chromatography. The Zellweger patient was found to excrete prostaglandin metabolites considerably less polar than those of the control subjects. The major urinary metabolite in the control subjects was practically absent in the urine from the Zellweger patient. The major urinary prostaglandin F2 alpha metabolite from the Zellweger patient was identified as an omega-oxidized C20-prostaglandin, 9,11-dihydroxy-15-oxoprost-5-ene-1,20-dioic acid. The major urinary prostaglandin F2 alpha metabolite from the control subjects had chromatographic properties of a tetranor (C16) prostaglandin, in accordance with earlier published data. The present results, in combination with our previous in vitro data, indicate that peroxisomal beta-oxidation is of major importance for in vivo chain shortening of prostaglandins. PMID:1885782

  9. Electromyographical study of uterine activity in the human during labour induced by prostaglandin F2 alpha.

    PubMed

    Lopes, P; Germain, G; Breart, G; Reitano, S; Le Houezec, R; Sureau, C

    1984-01-01

    In full-term pregnant women, electrical and mechanical activity of the uterus was monitored throughout the course of labour promoted by intravenous infusion of Pg F2 alpha. The recorded potentials were mostly biphasic and characterized by their long duration ranging from 1 to 2s. A wide range of potential amplitudes (100 microV to 1.8 mV) was observed according to the various patients. Early at the beginning of labour induction, the electrical complexes firing at various uterine sites were proved to be in close relationship and also well correlated with the mechanical events. This feature remained unchanged during labour. Potential amplitudes also remained unchanged during the same period of time. Under these conditions, improvement of uterine coordination does not appear to be the mechanism by which the increase of uterine contractile strength, necessary to expel the fetus, is obtained at the end of gestation. PMID:6584391

  10. The effect of inhibition of prostaglandin F2 alpha synthesis on placental expulsion in the ewe.

    PubMed Central

    Chassagne, M; Barnouin, J

    1993-01-01

    Five ewes were injected with two doses of a nonsteroidal anti-inflammatory drug (NSAI), lysine acetyl salicylate, at birth of their first lamb and one hour later, and five others were injected once only, at birth of their first lamb. A control group of six animals was constituted. The times needed for fetal expulsion and placental release were recorded. The peripheral plasma PgF2 alpha (as PGFM) levels were measured prepartum during the seven last days of gestation, at parturition, then 1 h, 2 h and 12 h after lambing. The results were compared among and within treatment groups. They indicate that the physiological increase in peripheral PGFM levels starts two days before lambing and that the level peaks at lambing. The normal decrease after parturition is emphasized by NSAI injections as detected 1 h and 2 h posttreatment (p < 0.01). The NSAI drug is short-acting as revealed by the lower PGFM levels in twice-treated animals 2 h after birth compared to once treated animals and the similar low levels in all three groups 12 h after birth. The fetal membranes were expelled normally in all treated and nontreated animals, but the time needed for placental expulsion in ewes injected with two doses of NSAI was longer than in controls (p < 0.05). A negative correlation (p < 0.05) was found between plasma PGFM levels measured two hours after lambing and the time needed for fetal membrane expulsion. PgF2 alpha appears to have a role in placental release in the ewe. PMID:8490813

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

    PubMed

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

    1997-12-01

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

  12. Control of luteal relaxin release by prostaglandin F2 alpha: differences in the sow cycle and pregnancy.

    PubMed

    Bagnell, C A; Baker, N K; McMurtry, J P; Brocht, D M; Lewis, G S

    1990-06-01

    The effect of an in vivo prostaglandin F2 alpha (PGF2 alpha) challenge in pregnant and cyclic sows was compared to determine whether PGF2 alpha-induced release of relaxin (RLX) from the corpus luteum (CL) in late pregnancy is also effective during the cycle. Ovarian venous RLX and progesterone were monitored by radioimmunoassay and RLX localized in the CL by immunohistochemistry. In Day 108 pregnant sows, infusion of PGF2 alpha (100 micrograms) into the ovarian artery resulted in an immediate and sustained rise in ovarian venous RLX with an initial decline in progesterone levels by 30 min which then returned to pretreatment levels. In Day 13 or 15 cyclic sows with functional corpora lutea (i.e., elevated progesterone), RLX was undetectable in ovarian venous blood after 100 micrograms of PGF2 alpha. Administration of PGF2 alpha via either the jugular vein or intramuscular route was also ineffective in releasing RLX from the CL of the cycle. The intensity of RLX immunostaining of the CL was similar in saline and PGF2 alpha-treated sows. These studies indicate that the control of RLX release from the sow CL differs in the estrous cycle and pregnancy. PMID:2349248

  13. Induction of abortion in the second trimester of pregnancy by intramuscular 15-methyl prostaglandin F 2 alpha (Prostin 15M).

    PubMed

    Novak-Antolic, Z; Assejev, V

    1982-01-01

    40 patients, pregnant clinically from 12 to 24 weeks in whom pregnancy termination for medical or medicosocial reasons was indicated, were given 250 micrograms Prostin 15M (15 methyl prostaglandin F 2 alpha, Upjohn) intramuscularly every three hours in total dose from 500 micrograms to 3000 micrograms. The Committee for Medical Ethics of the Committee for Medical and Social Security of SRS approved the study to be performed at the University Gynecological Hospital of Ljubljana using the drug and following the protocol of Upjohn (Tehnoservis). 36 patients (90%) aborted within 48 hours after the first injection (mean interval was 15.43 hours). In three out of 40 patients (7.5%) the abortion was complete, in 34 (85.0%) it was incomplete. In two patients, dilatation of cervical canal was complete, but the expected abortion did not take place. One patient aborted in 52 hours and 10 minutes. Only in a single case induction of abortion was completely unsuccessful. The drug is considered effective for induction of abortion in the second trimester of pregnancy. PMID:7172431

  14. Ovarian and hormonal responses of cows to treatment with an analogue of gonadotrophin releasing hormone and prostaglandin F2 alpha.

    PubMed

    Peters, A R; Ward, S J; Warren, M J; Gordon, P J; Mann, G E; Webb, R

    1999-03-27

    Blood samples were taken from 11 cows and their ovaries were scanned by ultrasound at least daily. Around day 5 of an induced cycle, they were injected with 10 micrograms buserelin, an analogue of gonadotrophin releasing hormone, and on day 12 they received 0.5 mg cloprostenol, an analogue of prostaglandin F2 alpha (PGF2 alpha). Two days later six of the cows (the treated group) received a second injection of 10 micrograms buserelin, but the remaining five received no further treatment (control group). The dominant, that is, the largest follicle in each cow disappeared after the first buserelin injection and was replaced by a new one which grew synchronously in all the cows until after the treatment with PGF2 alpha. Ovulation occurred significantly earlier after PGF2 alpha in the treated group than in the control group (72 to 96 hours v 96 to 120 hours; P < 0.05). Plasma progesterone concentrations then increased more rapidly in the treated group than in the control group and were significantly higher on days 3 and 4 after ovulation (P < 0.05). PMID:10230012

  15. Prostaglandin F2 alpha administered in vivo induces Ca2+-dependent protein phosphorylation in rat luteal tissue

    SciTech Connect

    Baum, M.S.

    1989-01-01

    The present study was performed in order to further elucidate the mechanism of action of PGF2 alpha in luteolysis in the rat ovary. Seven days after priming with superovulatory doses of pregnant mare serum gonadotropin and human chorionic gonadotropin to induce luteal tissue formation, the rats were injected with a luteolytic dose of the prostaglandin F2 alpha analogue cloprostenol. The ovaries were then homogenized, a 30,000 x g supernatant and pellet were prepared, whereafter aliquots of the preparations were incubated in the presence of (gamma-/sup 32/P)ATP with or without Ca2+. The phosphorylated proteins were separated by sodium dodecyl sulfate polyacrylamide gel electrophoresis and localized by autoradiography. The presence of Ca2+ caused an increased phosphorylation of a 45 kDa protein band in the particulate, but not in the cytosol, fraction. Furthermore, PGF2 alpha rapidly increased the /sup 32/P incorporation into the same protein band of 45 kDa. Thus, the PGF2 alpha-stimulated /sup 32/P incorporation was Ca2+-dependent and seen only in the particulate fraction. These results suggest that PGF2 alpha in its role as a luteolytic agent stimulates a Ca2+-dependent phosphorylation of a specific protein in luteal membranes of the rat ovary.

  16. Efficacy of intravaginal progesterone administration combined with prostaglandin f(2alpha) for cystic ovarian disease in Japanese Black cows.

    PubMed

    Iwakuma, Akihiro; Suzuki, Yoshihito; Haneishi, Takashi; Kajisa, Makoto; Kamimura, Shunichi

    2008-10-01

    The objective of this study was to investigate cystic ovarian disease (COD) in commercial Japanese Black cows and to evaluate the efficacy of 7-day insertion of an intravaginal progesterone insert (CIDR) combined with prostaglandin F(2alpha) (PGF(2alpha)) at CIDR removal. Experiment 1 was conducted to group cysts into 4 patterns based on alteration of plasma progesterone (P(4)) concentrations on d -7 and d 0 (=CIDR insertion) with 1.0 ng/ml as the cut-off level by ultrasonographic examination of 28 cows with COD that were >or=40 days postpartum and anoestrous after calving. In Experiment 2, a total of 55 cows under the same conditions as in Experiment 1 were utilized, and the same regimen as in Experiment 1 was performed without 7 days of pre-observation before treatment. As a result, 92.9% of CLs on d 21 were highly formed in Experiment 1 and 83.6% were highly formed in Experiment 2. The conception rates within 60 days after CIDR removal were also satisfactory high and were 71.4% and 54.5%, respectively. There were no differences in any overall reproductive parameters between Experiments 1 and 2 (P>0.05). The average days between CIDR removal and conception were 24.4 +/- 5.3 and 24.0 +/- 6.5 days, respectively (P>0.05); therefore, the conception dates of the cows in Experiment 2 were at least 7 days earlier compared with Experiment 1. In conclusion, treatment with a CIDR and PGF(2alpha) against COD could minimize the risk of incorrect treatment and provide sufficient reproductive performance in Japanese Black cows. PMID:18981664

  17. Prostaglandin F(2alpha) suppresses early phase of adipogenesis, but is not associated with osteoblastogenesis in mouse mesenchymal stem cells.

    PubMed

    Fujimori, Ko; Ueno, Toshiyuki; Amano, Fumio

    2010-09-01

    In this study, we investigated the roles of prostaglandin (PG) F(2alpha) in the differentiation of mouse ST2 mesenchymal stem cells (MSC) into adipocytes and osteoblasts. PGF(2alpha) was not produced in the undifferentiated ST2 MSC, but its highest level of production was detected at 3h after the initiation of adipogenesis and then quickly decreased. On the contrary, apparent PGF(2alpha) production was not detected during the osteoblastogenesis of ST2 MSC. The PGF(2alpha) production pattern during adipogenesis well resembled the expression profiles of aldo-keto reductase (AKR) 1B3, which acted as the PGF(2alpha) synthase, and cyclooxygenase-2 genes; but the pattern showed a slight delay compared with these profiles. The siRNA for AKR1B3, but not that for AKR1B8 or 1B10, decreased PGF(2alpha) production and enhanced the expression of adipogenic genes, but did not affect the mRNA levels of osteoblastogenic genes, during the adipogenesis of ST2 MSC. The FP receptor was expressed during adipogenesis of ST2 MSC, and its agonist or antagonist suppressed or enhanced, respectively, the lipid accumulation and the adipogenic gene expression; but this receptor was not associated with the osteoblastogenesis. These results indicate that AKR1B3-mediated PGF(2alpha) suppressed the early phase of adipogenesis through FP receptors, but did not affect osteoblastogenesis in ST2 MSC. Therefore, PGF(2alpha) suppressed the progression of early phase adipogenesis after determination of the cell fate that causes MSC to differentiate into adipocytes. PMID:20601070

  18. Comparison of prostaglandin F2alpha, bimatoprost (prostamide), and butaprost (EP2 agonist) on Cyr61 and connective tissue growth factor gene expression.

    PubMed

    Liang, Yanbin; Li, Chen; Guzman, Victor M; Evinger, Albert J; Protzman, Charles E; Krauss, Achim H-P; Woodward, David F

    2003-07-18

    Connective tissue growth factor (CTGF) and Cyr61 (cysteine-rich angiogenic protein 61) are members of the CCN gene family that encode multifunctional, extracellular matrix-associated signaling proteins. Because the mechanism of action of certain anti-glaucoma drugs involves extracellular matrix remodeling of ocular ciliary muscle, with a resultant increase in drainage of aqueous humor from the eye, we compared the effects of three pharmacologically distinct ocular hypotensive agents on Cyr61 and CTGF gene expression. Thus, prostaglandin F2alpha (PGF2alpha) (FP receptor agonist), Butaprost (EP2 receptor agonist), and Bimatoprost (a prostamide) were compared. Using Affymetrix gene chip technology, we first identified that PGF2alpha dramatically up-regulated Cyr61 and CTGF mRNA expression in HEK 293/EBNA cells (hFP-HEK 293/EBNA). Northern blot further confirmed the Cyr61 and CTGF up-regulation is in a dose- and time-dependent manner. PGF2alpha-induced up-regulation of Cyr61 appeared to exclusively involve the Rho pathway, and up-regulation of CTGF was via multiple intracellular pathways. Because prostamide receptors are, to date, defined only at the pharmacological level, Bimatoprost effects on Cyr61 and CTGF were studied in the isolated feline iris sphincter preparation, a tissue highly responsive to prostamides. Both PGF2alpha and Bimatoprost up-regulated Cyr61 mRNA expression in the cat iris tissue. Only PGF2alpha up-regulated CTGF mRNA expression in the cat iris. Therefore, PGF2alpha and Bimatoprost appear to interact with different receptors populations in the cat iris, according to their markedly different effects on CTGF. Activation of prostaglandin EP2 receptors (Gs-coupled) also up-regulated Cyr61 but not CTGF mRNA expression in the isolated cat iris. Similar data were observed in human primary ciliary smooth muscle cells. Thus, despite quite different signal transduction pathways, FP receptor stimulation up-regulates CTGF and Cyr61. The prostamide analog

  19. [The influence of intravenous laser therapy on prostaglandin E2 and F2-alpha dynamics and the state of microcirculation in the patients presenting with gastroesophageal reflux disease].

    PubMed

    Burduli, N M; Tadtaeva, D Ia

    2012-01-01

    The objective of the present work was to study the influence of low-frequency laser radiation on the levels of prostaglandins E2 and F2-alpha and characteristics of microcirculation in the patients suffering from gastroesophageal reflux disease (GERD). A total of 112 patients at the age from 19 to 79 years presenting with GERD were examined. 78 of them were given the complete 10-day course of intravenous laser therapy based on a Matriks-VLOK ("Matriks", Russia) therapeutic laser set emitting in the continuous mode at a wavelength of 0.405 mcm with the radiation power 1-11.5 mW at the output of the main lightguide. The characteristics of interest were determined before and after the treatment. It was shown that laser irradiation resulted in the elevation of pro-inflammatory prostaglandin levels and the improvement of parameters of microcirculation. PMID:23373291

  20. Stable analogs of prostaglandins E1 and F2 alpha ameliorate the proteinuria of aminonucleoside-of-puromycin nephrosis in Lewis rats.

    PubMed Central

    Ulich, T. R.; Meline, J. A.; Ni, R. X.; Keys, M.; Wu, C. H.

    1987-01-01

    Prostaglandins have been implicated by previous investigators in the pathogenesis of the nephrotic syndrome. A single subcutaneous injection of 1 mg/kg of stable analogs of prostaglandins E1 or F2 alpha (15[S]-15-methyl -PGE1 [M-PGE1] and -PGF2 alpha [M-PGF2 alpha]) was found in the present study to dramatically decrease proteinuria on Day 10 of puromycin aminonucleoside (PAN) nephrosis in Lewis rats. The decrease in proteinuria was mediated at least in part by a decrease in glomerular filtration rate (GFR), as quantitated by inulin clearances in nephrotic control and prostaglandin-treated rats. M-PGE1, moderately, and M-PGF2 alpha, to a lesser degree, also decreased the GFR in normal rats. Interestingly, the GFR was dramatically decreased in nephrotic as compared with nonnephrotic control rats, which suggests that PAN nephrosis may not be an ideal experimental model for human minimal change nephrosis in which the GFR is usually not severely compromised. The prostaglandin-induced decrease in GFR in both nephrotic and normal rats was coincident with a drop in systemic blood pressure. Nephrotic rats, however, had a slightly higher baseline blood pressure than normals, and the hypotensive effects of both prostaglandins were much less in nephrotic than in normal rats. The decrease in proteinuria was not related to a cytoprotective effect, as indicated by the failure of daily doses of 5 micrograms/kg M-PGE1 to reduce proteinuria 6, 8, or 10 days after injection of puromycin aminonucleoside. The similar antiproteinuric effects of prostaglandin synthesis inhibitors and of pharmacologic doses of prostaglandins are somewhat paradoxical but are reminiscent of the similarly paradoxical mutual antiinflammatory effects of these agents. The high doses of prostaglandins required to reduce proteinuria as well as their reduction of blood pressure and GFR will limit their clinical usefulness in the nephrotic syndrome. PMID:3499082

  1. Profiling of Luteal Transcriptome during Prostaglandin F2-Alpha Treatment in Buffalo Cows: Analysis of Signaling Pathways Associated with Luteolysis

    PubMed Central

    Suganthi, Hepziba; Rudraiah, Medhamurthy

    2014-01-01

    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. PMID:25102061

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

    PubMed

    Miao, Yun-gen; Jiang, Li-jun

    2003-01-01

    The growth of the silkworm is influenced by the outside and inside environment. Among them, the category of various endocrine hormone of inside is the main factors that adjust the characters such as growth and propagate. In this experiment, we applied different dosage of prostaglandin to the fourth and fifth instar silkworm to observe the effects of prostaglandin F2alpha (PGF2alpha) on silk gland growth, mid-gut biochemical constituents and the lipid profiles of silkworm larva, Bombyx mori L. The weight of the posterior silk gland increased significantly (P < 0.001) by 20-24% after treatment with PGF2alpha. The increase in the lipid profiles except lipase activity suggests that the silk gland had more synthetic activity that might reflect in active spinning of silkworm larva. The changes of total proteins, free amino acids and alkaline phosphatase in mid-gut of control and PGF2alpha treated silkworm, B. mori L. indicate that PGF2alpha favored stimulatory effect on physiology of digestion, absorption and transportation of nutrients which might influence on the growth and development of larva. PMID:12611497

  3. [Genetic variation and association of prostaglandin F2alpha receptor (PTGFR) gene with sow maternal behaviors in a White Duroc x Erhualian resource population].

    PubMed

    Yang, Zhu-Qing; Ren, Jun; Zhang, Zhi-Yan; Chen, Cong-Ying

    2010-11-01

    Maternal behaviors of sows around parturition are important for survival of newborn offspring. Failure to establish normal maternal bonds such as maternal infanticide and crushing often occurs in some individuals. It causes both significant economic losses to the pig industry and severe problems of piglet welfare. Prostaglandin F2-alpha not only can stimulate the nest-building behavior of sows before parturition but also plays an important role in reproductive process and maternal behavior through protein FP encoded by the prostaglandin F receptor gene (PTGFR) as its receptor. In this study, genetic variation and association study of PTGFR gene with nest-building behavior, maternal infanticide, and crushing behavior was carried out in a White Duroc x Erhualian resource population. As a result, five synonymous mutations were identified on exon 1 and exon 2. Exon 1 g .250 A>G, Exon 1 g.619 G>A and Exon 2 g.483 T>C were chosen for genotyping in individuals of F0, F1 and 289 F2 sows. Family-based transmission disequilibrium test (TDT) demonstrated that there were no significant associations of 3 SNPs and haplotypes of PTGFR gene with sow nest-building, maternal infanticide and crushing behavior (P > 0.05). Therefore, it can be concluded that PTGFR gene is not the causative candidate gene for sow maternal behaviors. PMID:21513166

  4. Mechanical stimulation of skeletal muscle increases prostaglandin F2(alpha) synthesis and cyclooxygenase activity by a pertussis toxin sensitive mechanism

    NASA Technical Reports Server (NTRS)

    Vandenburgh, Herman H.; Shansky, Janet; Solerssi, Rosa; Chromiak, Joseph

    1992-01-01

    Repetitive mechanical stimulation of differentiated skeletal muscle in tissue culture increases the production of prostaglandin F(sub 2(alpha)), an anabolic stimulator of myofiber growth. Within 4 h of initiating mechanical activity, the activity of cyclooxygenase, a regulatory enzyme in prostaglandin synthesis, was increased 82% (P is less than .005), and this increase was maintained for at least 24 h. Kinetic analysis of the stretch-activated cyclooxygenase indicated a two to three-fold decrease in the enzyme's K(sub m) with no change in V(sub max). The stretch-induced increase in enzymatic activity was not inhibited by cycloheximide, was independent of cellular electrical activity (tetrodotoxin-insensitive), but was prevented by the G protein inhibitor pertussis toxin. Pertussis toxin also inhibited the stretch-induced increases in PGF(sub 2(alpha)) production, and cell growth. It is concluded that stretch of skeletal muscle increases the synthesis of the anabolic modulator PGF(sub 2(alpha)) by a G protein-dependent process which involves activation of cyclooxygenase by a posttranslational mechanism.

  5. Differential effects of n-3 and n-6 fatty acids on prostaglandin F2alpha production by bovine endometrial cells.

    PubMed

    Caldari-Torres, C; Rodriguez-Sallaberry, C; Greene, E S; Badinga, L

    2006-03-01

    Recent studies have implicated n-3 polyunsaturated fatty acids in the reduction of eicosanoid production in the bovine uterus. The objective of this study was to determine whether the effect of eicosapentaenoic acid (EPA; C(20:5), n-3) on PGF2alpha production by bovine endometrial (BEND) cells is influenced by the quantity of linoleic acid (C(18:2), n-6) in the incubation medium. Confluent BEND cells were incubated in the absence (control) or presence of 100 microM of EPA for 24 h. After incubation, cells were rinsed and then stimulated with phorbol 12,13-dibutyrate (PDBu; 100 ng/mL) for 6 h. Additional sets of culture dishes were treated with a combination of EPA and increasing n-6/n-3 fatty acid ratios for 24 h and then challenged with PDBu for 6 h. The PDBu stimulated PGF2alpha secretion and upregulated steady-state concentrations of prostaglandin endoperoxide synthase-2 and peroxisome proliferator-activated receptor delta mRNA within 6 h. Preincubation of BEND cells with EPA for 24 h decreased PGF2alpha response to phorbol ester, but had no detectable effects on prostaglandin endoperoxide synthase-2 or peroxisome proliferator-activated receptor delta mRNA abundance in PDBu-stimulated BEND cells. The inhibitory effect of EPA on PGF2alpha production was reverted in BEND cells treated with an increasing n-6-to-n-3 fatty acid ratio. Findings indicate that the net inhibition of endometrial PGF2alpha bioynthesis by n-3 fatty acids may vary depending on the ratio of n-6 to n-3 fatty acids in the uterus. PMID:16507691

  6. Generation of the isoprostane 8-epi-prostaglandin F2alpha in vitro and in vivo via the cyclooxygenases.

    PubMed

    Klein, T; Reutter, F; Schweer, H; Seyberth, H W; Nüsing, R M

    1997-09-01

    F2-isoprostanes are isomers of the prostaglandin PGF2alpha. At least one compound of this group, 8-epi-PGF2alpha, exhibits biological activity, and therefore special interest is focused on the mechanism of isoprostane formation: enzyme catalyzed or radical mediated. We analyzed the formation of isoprostanes in vitro and in vivo. In both systems, purified cyclooxygenase isoenzymes and cell models specific for the cyclooxygenase isoenzymes, 8-epi-PGF2alpha formation could be totally suppressed by cyclooxygenase inhibitors. Indomethacin inhibited concentration-dependent 8-epi-PGF2alpha formation in platelets stimulated with calcium ionophore, arachidonic acid or thrombin. Nordihydroguaiaretic acid, an antioxidant, blocked isoprostane formation with a similar IC50 value as thromboxane B2 synthesis, pointing toward cyclooxygenase as the primary target of inhibition. Based on the turnover number, cyclooxygenase-2 formed higher levels of 8-epi-PGF2alpha than cyclooxygenase-1. Endogenous 8-epi-PGF2alpha production in rat mesangial cells correlated well with the mRNA and protein expression of cyclooxygenase-2 during interleukin-1 induction. However, in contrast to human platelets, which produced different forms of isoprostanes, rat mesangial cells appeared to form only 8-epi-PGF2alpha. Further, this indicates that mesangial cells may represent a cellular origin for renal 8-epi-PGF2alpha formation. Next, we analyzed the formation of isoprostanes in humans. A direct correlation was observed between indomethacin treatment and the decrease in 8-epi-PGF2alpha and isoprostane levels, but compared with other prostanoids the inhibition was less pronounced. In summary, based on the in vitro studies, a clear cyclooxygenase-dependent formation of isoprostanes, especially 8-epi-PGF2alpha, was observed. However, in vivo additional formation via cyclooxygenase enzyme-independent mechanisms is likely. PMID:9316884

  7. Actions of prostaglandin F2 alpha and noradrenaline on calcium exchange and contraction in rat mesenteric arteries and their sensitivity to calcium entry blockers.

    PubMed Central

    Godfraind, T.; Miller, R. C.

    1982-01-01

    1 The actions of prostaglandin F2 alpha (PGF2 alpha) and noradrenaline on contraction and 45Ca exchange have been studied in rat mesenteric arteries. 2 PGF2 alpha and noradrenaline contracted rat isolated mesenteric artery preparations to about the same extent. The PGF2 alpha-stimulated contractions, unlike those produced by noradrenaline, were completely inhibited in calcium-free physiological solution. 3 The calcium entry blocking drugs, cinnarizine and flunarizine, had little effect on the resting exchange of calcium in the arterial smooth muscle, but inhibited PGF2 alpha-stimulated contractions and 45Ca uptake to a similar extent. 4 Flunarizine was about 7 fold more potent as an inhibitor of noradrenaline- than of PGF2 alpha-mediated contraction and 45Ca uptake and this ratio was about 50 for cinnarizine. 5 EGTA (1.25 mM) produced a relaxation of noradrenaline and PGF2 alpha-induced maximal contractions. Measured over the first 2 min of EGTA contact, the rate of relaxation was much faster in noradrenaline than in PGF2 alpha-stimulated preparations. 6 Turnover of cellular calcium (influx plus efflux) during the first 2 min of noradrenaline contact was much greater than that produced by PGF2 alpha, largely due to a greater effect of noradrenaline on calcium efflux. 7 The results suggest that PGF2 alpha-but not noradrenaline-induced contractions are entirely dependent on the influx of extracellular calcium and that the agonists may stimulate calcium gating mechanisms differently. PMID:6951620

  8. Maintained reduction of intraocular pressure by prostaglandin F2 alpha-1-isopropyl ester applied in multiple doses in ocular hypertensive and glaucoma patients.

    PubMed

    Camras, C B; Siebold, E C; Lustgarten, J S; Serle, J B; Frisch, S C; Podos, S M; Bito, L Z

    1989-09-01

    In a randomized, double-masked, placebo-controlled study, 0.25 microgram (n = 11) or 0.5 microgram (n = 13) of prostaglandin F2 alpha-1-isopropyl ester (PGF2 alpha-IE) was applied topically twice daily for 8 days to one eye of ocular hypertensive or chronic open-angle glaucoma patients. Compared with contralateral, vehicle-treated eyes, PGF2 alpha-IE significantly (P less than 0.05) reduced intraocular pressure (IOP), beginning 4 hours after the first 0.5-microgram dose and lasting at least 12 hours after the fourteenth dose, with a significant (P less than 0.005) mean reduction of 4 to 6 mmHg maintained throughout the last day of therapy with either dose. A contralateral effect was not observed. Mean tonographic outflow facility was significantly (P less than 0.05) higher in PG-treated compared with vehicle-treated eyes (0.17 +/- 0.02 versus 0.12 +/- 0.01 microliter/minute/mmHg, respectively; +/- standard error of the mean) for the 0.5 microgram dose. Conjunctival hyperemia reached a maximum at 30 to 60 minutes after PGF2 alpha-IE application. Some patients reported mild irritation lasting several minutes after some doses. Visual acuity, accommodative amplitude, pupillary diameter, aqueous humor flare, anterior chamber cellular response, Schirmer's test, pulse rate, and blood pressure were not significantly altered. Our findings show that PGF2 alpha-IE is a potent ocular hypotensive agent and a promising drug for glaucoma therapy. PMID:2780003

  9. Effects of yohimbine, rauwolscine and corynanthine on contractions and calcium fluxes induced by depolarization and prostaglandin F2 alpha in rat aorta.

    PubMed Central

    Godfraind, T.; Miller, R. C.; Socrates Lima, J.

    1983-01-01

    The effects of the selective alpha 2-adrenoceptor antagonists yohimbine and its stereo-isomer rauwolscine and the selective alpha 1-adrenoceptor antagonist corynanthine (a third yohimbine stereoisomer) on contractions induced in rat aorta by depolarization and prostaglandin F2 alpha (PGF2 alpha) have been compared. In calcium-free solution, depolarization with 100 mM K+ failed to produce a contraction of rat aorta but PGF2 alpha (3 microM) stimulated a contraction equal to about 23% of maximal elicited in normal physiological solution. Yohimbine had no significant effect on depolarization-induced contractions except at concentrations greater than 30 microM. Rauwolscine and corynanthine (1 to 100 microM) depressed depolarization-induced contractions in a concentration-dependent manner, but the characteristics of inhibition were not identical. Contractions induced by PGF2 alpha (3 microM) were depressed in a concentration-dependent manner by rauwolscine (3 to 100 microM) but were unaffected by yohimbine or corynanthine. Depolarization-stimulated 45Ca influx was depressed by rauwolscine and corynanthine to about the same extent as were the contractions; while rauwolscine (100 microM) completely inhibited PGF2 alpha-stimulated 45Ca influx, it also depressed part of the PGF2 alpha-stimulated contraction dependent on intracellular calcium. Rauwolscine (100 microM) partly inhibited PGF2 alpha-stimulated release of 45Ca from aortic smooth muscle in calcium-free solution. It is concluded that the yohimbine structure possesses a calcium entry blocking action as well as a depressant action on contractions not dependent on calcium entry. The predominant effect depends on the structural configuration and the nature of the stimulating agent. PMID:6580937

  10. Decreased Cholesterol Uptake and Increased Liver X Receptor-Mediated Cholesterol Efflux Pathways During Prostaglandin F2 Alpha-Induced and Spontaneous Luteolysis in Sheep1

    PubMed Central

    Seto, Nickie L.; Bogan, Randy L.

    2015-01-01

    In nonprimate species, it has been well established that prostaglandin F2 alpha (PGF2alpha) initiates luteolysis. Changes in intracellular cholesterol concentrations caused by modulation of cholesterol uptake and efflux may mediate PGF2alpha-induced luteolysis. These changes in cholesterol efflux and uptake are controlled, in part, by the liver x receptors (LXR) alpha (NR1H3) and beta (NR1H2), nuclear receptors that increase expression of genes necessary for cholesterol efflux or limiting cholesterol uptake. Therefore, we hypothesized that PGF2alpha reduces expression of cholesterol uptake and increases expression of cholesterol efflux genes, mediated in part by enhanced LXR activity. To test this hypothesis, an induced luteolysis model was used whereby ewes were treated during their midluteal phase with saline or PGF2alpha and corpora lutea (CL) collected 12, 24, or 48 h later for determination of mRNA and protein concentrations by quantitative real-time PCR and Western blot analysis, respectively. As a complementary approach, CL undergoing spontaneous luteolysis were compared to midluteal phase CL. The lipoprotein receptors responsible for cholesterol uptake were significantly decreased in both luteolysis models. Expression of the LXR target gene ATP binding cassette subfamily A1 (ABCA1), an important mediator of cholesterol efflux, was significantly increased in both experimental models. Chromatin immunoprecipitation confirmed that PGF2alpha treatment resulted in enhanced NR1H3 and NR1H2 binding to the ABCA1 promoter. Qualitative changes in lipid droplet distribution were also observed following PGF2alpha treatment. These data support the hypothesis that reduced cholesterol uptake and increased efflux mediate luteolysis in sheep, which is partially controlled by PGF2alpha stimulation of LXR activity. PMID:25882703

  11. Effects of a single administration of prostaglandin F2alpha, or a combination of prostaglandin F2alpha and prostaglandin E2, or placebo on fertility variables in dairy cows 3–5 weeks post partum, a randomized, double-blind clinical trial

    PubMed Central

    Hirsbrunner, Gaby; Burkhardt, Heinz W; Steiner, Adrian

    2006-01-01

    Background Delayed uterine involution has negative effects on the fertility of cows; use of prostaglandin F2alpha alone as a single treatment has not been shown to consistently improve fertility. Combined administration of PGF2alpha and PGE2 increased uterine pressure in healthy cows. We hypothesized, that the combination of both prostaglandins would accelerate uterine involution and have, therefore, a positive effect on fertility variables. In commercial dairy farming, the benefit of a single post partum combined prostaglandin treatment should be demonstrated. Methods 383 cows from commercial dairy farms were included in this study. Uterine size and secretion were evaluated at treatment 21–35 days post partum and 14 days later. Cows were randomly allocated to one of three treatment groups: PGF2alpha and PGE2, PGF2alpha or placebo. For every animal participating in the study, the following reproduction variables were recorded: Interval from calving to first insemination, days open, number of artificial inseminations (AI) to conception; subsequent treatment of uterus, subsequent treatment of ovaries. Plasma progesterone level at time of treatment was used as a covariable. For continuous measurements, analysis of variance was performed. Fisher's exact test for categorical non-ordered data and exact Kruskal-Wallis test for ordered data were used; pairwise group comparisons with Bonferroni adjustment of significance level were performed. Results There was no significant difference among treatment groups in uterine size. Furthermore, there was no significant difference among treatments concerning days open, number of AI, and subsequent treatment of uterus and ovaries. Days from calving to first insemination tended to be shorter for cows with low progesterone level given PGF2alpha and PGE2 in combination than for the placebo-group (P = 0.024). Conclusion The results of this study indicate that the administration of PGF2alpha or a combination of PGF2alpha and PGE2 21 to

  12. Prostaglandin F2 alpha-induced calcium transient in ovine large luteal cells: II. Modulation of the transient and resting cytosolic free calcium alters progesterone secretion.

    PubMed

    Wegner, J A; Martinez-Zaguilan, R; Gillies, R J; Hoyer, P B

    1991-02-01

    A previous study demonstrated that prostaglandin F2 alpha (PGF2 alpha) stimulates a transient increase in cytosolic free Ca2+ levels [( Ca2+]i) in ovine large luteal cells. In the present study, the magnitude of the PGF2 alpha (0.5 microM)-induced calcium transient in Hanks' medium (87 +/- 2 nM increase above resting levels) was reduced (P less than 0.05) but not completely eliminated in fura-2 loaded large luteal cells incubated in Ca2(+)-free or phosphate- and carbonate-free medium (10 +/- 1 nM, 32 +/- 6 nM, above resting levels; respectively). Preincubation for 2 min with 1 mM LaCl3 (calcium antagonist) eliminated the PGF2 alpha-induced calcium transient. The inhibitory effect of PGF2 alpha on secretion of progesterone was reduced in Ca2(+)-free medium or medium plus LaCl3. Resting [Ca2+]i levels and basal secretion of progesterone were both reduced (P less than 0.05) in large cells incubated in Ca2(+)-free medium (27 +/- 4 nM; 70 +/- 6% control, respectively) or with 5 microM 5,5'-dimethyl bis-(O-aminophenoxy)ethane-N,N,N'N'-tetraacetic acid (40 +/- 2 nM; 49 +/- 1% control; respectively). In addition, secretion of progesterone was inhibited (P less than 0.05) by conditions that increased (P less than 0.05) [Ca2+]i; that is LaCl3 ([Ca2+]i, 120 +/- 17 nM; progesterone, 82 +/- 8% control) and PGF2 alpha ([Ca2+]i, 102 +/- 10 nM; progesterone, 82 +/- 3% control). In small luteal cells, resting [Ca2+]i levels and secretion of progesterone were reduced by incubation in Ca2(+)-free Hanks ([Ca2+]i, 28 +/- 2 nM; progesterone, 71 +/- 6% control), however, neither LaCl3 nor PGF2 alpha increased [Ca2+]i levels or inhibited secretion of progesterone. The findings presented here provide evidence that extracellular as well as intracellular calcium contribute to the PGF2 alpha-induced [Ca2+]i transient in large cells. Furthermore, whereas an adequate level of [Ca2+]i is required to support progesterone production in both small and large cells, optimal progesterone production in

  13. Effects of prostaglandin F2 alpha on bone formation and resorption in cultured neonatal mouse calvariae: Role of prostaglandin E2 production

    SciTech Connect

    Raisz, L.G.; Alander, C.B.; Fall, P.M.; Simmons, H.A. )

    1990-02-01

    Although most studies show that prostaglandin E2 (PGE2) is the most potent and effective of the prostanoids in bone, recent data in cell culture suggest that PGF2 alpha may have unique effects, particularly on cell replication. The present study was undertaken to compare the effects of PGF2 alpha and PGE2 in cultured neonatal mouse parietal bones by simultaneous measurement of bone resorption as release of previously incorporated 45Ca, bone formation as incorporation of (3H)proline into collagenase-digestible (CDP) and noncollagen protein, and DNA synthesis as incorporation of (3H)thymidine. PGF2 alpha was less effective than PGE2 as a stimulator of bone resorption, and its effects were partially inhibited by indomethacin and markedly inhibited by glucocorticoids. In contrast, the resorptive response to PGE2 was unaffected by indomethacin and only partially inhibited by cortisol. PGF2 alpha had little effect on bone formation, in contrast to the biphasic effect of PGE2, which inhibited labeling of CDP in the absence of cortisol and stimulated CDP labeling in the presence of cortisol. PGF2 alpha increased thymidine incorporation into DNA, but the effect was smaller than that of PGE2 and was inhibited by indomethacin. These observations suggested that PGF2 alpha might act in part by stimulating PGE2 production. By RIA, PGE2 concentrations were increased in the medium of bones treated with PGF2 alpha, and this increase was blocked by indomethacin. By HPLC, bones prelabeled with (3H)arachidonic acid showed an increase in labeled PGE2 release, and RIA showed an increase in PGE2 after PGF2 alpha treatment. These results indicate that PGF2 alpha is a relatively weak agonist in bone compared to PGE2 and that some of the effects of PGF2 alpha on bone resorption, formation, and cell replication may be mediated by an increase in endogenous PGE2 production.

  14. Evidence for human thromboxane receptor heterogeneity using a novel series of 9,11-cyclic carbonate derivatives of prostaglandin F2 alpha.

    PubMed Central

    Krauss, A. H.; Woodward, D. F.; Gibson, L. L.; Protzman, C. E.; Williams, L. S.; Burk, R. M.; Gac, T. S.; Roof, M. B.; Abbas, F.; Marshall, K.; Senior, J.

    1996-01-01

    1. The pharmacological activity of a novel series of 9,11-cyclic carbonate derivatives of prostaglandin F2 alpha (PGF2 alpha) was investigated in various isolated smooth muscle preparations possessing different prostanoid receptor subtypes as well as in human platelets. Since subdivision of thromboxane (TP-) receptors into vascular/smooth muscle and platelet subtypes is a controversial subject, our studies included a human smooth muscle preparation (myometrium) in addition to the widely used rat aorta and human platelets as TP-receptor preparations. 2. Two members of that series, AGN191976 and AGN192093 were found to be highly potent and selective thromboxane-mimetics. AGN191976 and AGN192093 contracted isolated tissues of the rat thoracic aorta with EC50 values of 0.32 +/- 0.08 and 1.30 +/- 0.53 nM, respectively. Both agonists were at least 10 times more potent than the benchmark TP-agonist, U-46619, in this preparation, whilst being at least 500 times less potent at other prostanoid receptors (DP, EP1, EP3, FP, IP) in vitro. 3. In human myometrial strips from pregnant and non-pregnant donors, both AGN191976 and AGN192093 were potent contractile agonists. The rank order of potency in myometrium of AGN191976 > AGN192093 > U-46619 correlated well with that in the rat aorta. In human platelet-rich plasma (PRP), however, AGN191976 had potent proaggregatory activity (EC50 = 16.3 +/- 1.4 nM), which is a TP-receptor-mediated event, whereas AGN192093 was a much weaker agonist (EC50 = 37.9 +/- 2.0 microM). AGN192093 did not behave as an antagonist in the platelets, since it did not antagonize platelet aggregation induced by ADP, arachidonic acid, U-46619 or AGN191976. In human washed platelets, the activity profile of AGN191976 (EC50 = 4.15 +/- 0.52 nM) and AGN192093 (no aggregation up to 10 microM) was similar to that obtained in PRP. 4. The involvement of TP-receptors was verified with the potent TP-antagonist, SQ29548. SQ29548 (0.1 microM in myometrium; 1 microM in

  15. Differential gene expression in the bovine corpus luteum during transition from early phase to midphase and its potential role in acquisition of luteolytic sensitivity to prostaglandin F2 alpha.

    PubMed

    Goravanahally, Madhusudan P; Salem, Mohamed; Yao, Jianbo; Inskeep, E Keith; Flores, Jorge A

    2009-05-01

    Prostaglandin F2 alpha (PGF(2alpha)) brings about regression of the bovine corpus luteum (CL). This luteolytic property of PGF(2alpha) is used in beef and dairy cattle to synchronize estrus. A limitation of this protocol is insensitivity of the early CL to luteolytic actions of PGF(2alpha). The mechanisms underlying this differential luteal sensitivity are poorly understood. The developing CL has a maximum number of PGF(2alpha) receptors; therefore, differences in signaling events may be responsible for luteal insensitivity. Hence, differential gene expression at two developmental stages of CL, Day 4 (D-4) and D-10 after estrus, might account for differences in signal transduction pathways associated with luteal sensitivity. This possibility was examined in these studies. Microarray analysis (n = 3 cows per stage) identified 167 genes that were differentially expressed (P < 0.05). These were categorized into genes involved in protein biosynthesis and modification (18.5%), transcription regulation and DNA biosynthesis (18.5%), miscellaneous (17.0%), cell signaling (12.0%), steroidogenesis and metabolism (10.2%), extracellular matrix and cytoskeletal proteins (9.5%), unknown functions (6.0%), protein degradation (5.3%), and antioxidant property (3.0%). Real-time PCR confirmed the differential expression of nine selected genes, including tyrosine 3-monooxygenase/tryptophan 5-monooxygense activation protein zeta polypeptide (YWHAZ) and regulator of G protein signaling 2 24-kDa (RGS2), observed in microarray. Furthermore, the in vivo effect of exogenous PGF(2alpha) (n = 3 cows per stage) on selected genes that were found to be differentially expressed during this developmental transition was examined. PGF(2alpha) increased the expression of a guanine nucleotide-binding protein (G protein) beta polypeptide 1 (GNB1) in D-4 CL and calcium/calmodulin-dependent kinase kinase 2 beta (CAMKK2) in D-10 CL. Therefore, GNB1, CAMKK2, YWHAZ, and RGS2 are candidate genes that may

  16. Desensitization of prostaglandin F2 alpha-stimulated inositol phosphate generation in NIH-3T3 fibroblasts transformed by overexpression of normal c-Ha-ras-1, c-Ki-ras-2 and c-N-ras genes.

    PubMed Central

    Black, F M; Wakelam, M J

    1990-01-01

    The stimulation of inositol phosphate generation in control and ras-gene-transformed NIH-3T3 cells by prostaglandin F2 alpha (PGF2 alpha) was investigated. Compared with the control cells, a desensitization of the response was observed in cells transformed by the overexpression of N-, Ha-, or Ki-ras genes. This desensitization was without effect upon the concentration causing half-maximal effect (EC50), dissociation constant (Kd) or number of PGF2 alpha receptors. Inhibition of PG synthesis was without effect upon desensitization, demonstrating that the effect was not agonist-induced. Desensitization could be induced in NIH-3T3 cells by culturing under conditions where the cells were all in the exponential growth phase, or by a 12 h exposure to a C-kinase-activating phorbol ester. These results suggest that desensitization of certain agonist-induced inositol phospholipid responses in ras-transformed cells is a consequence of increased cell proliferation and associated amplification in C-kinase activity and is an indirect consequence of transformation by ras. PMID:2187437

  17. Prostaglandin (PG) F2 Alpha Synthesis in Human Subcutaneous and Omental Adipose Tissue: Modulation by Inflammatory Cytokines and Role of the Human Aldose Reductase AKR1B1

    PubMed Central

    Michaud, Andréanne; Lacroix-Pépin, Nicolas; Pelletier, Mélissa; Veilleux, Alain; Noël, Suzanne; Bouchard, Céline; Marceau, Picard; Fortier, Michel A.; Tchernof, André

    2014-01-01

    Introduction PGF2α may be involved in the regulation of adipose tissue function. Objectives 1) To examine PGF2α release by primary preadipocytes, mature adipocytes and whole tissue explants from the subcutaneous and omental fat compartments; 2) To assess which PGF synthase is the most relevant in human adipose tissue. Methods Fat samples were obtained by surgery in women. PGF2α release by preadipocytes, adipocytes and explants under stimulation by TNF-α, IL-1β or both was measured. Messenger RNA expression levels of AKR1B1 and AKR1C3 were measured by RT-PCR in whole adipose tissue and cytokine-treated preadipocytes. The effect of AKR1B1 inhibitor ponalrestat on PGF2α synthesis was investigated. Results PGF2α release was significantly induced in response to cytokines compared to control in omental (p = 0.01) and to a lesser extent in subcutaneous preadipocytes (p = 0.02). Messenger RNA of COX-2 was significantly higher in omental compared to subcutaneous preadipocytes in response to combined TNF-α and IL-1β (p = 0.01). Inflammatory cytokines increased AKR1B1 mRNA expression and protein levels (p≤0.05), but failed to increase expression levels of AKR1C3 in cultured preadipocytes. Accordingly, ponalrestat blunted PGF2α synthesis by preadipocytes in basal and stimulated conditions (p≤0.05). Women with the highest PGF2α release by omental adipocytes had a higher BMI (p = 0.05), waist circumference (p≤0.05) and HOMAir index (p≤0.005) as well as higher mRNA expression of AKR1B1 in omental (p<0.10) and subcutaneous (p≤0.05) adipose tissue compared to women with low omental adipocytes PGF2α release. Positive correlations were observed between mRNA expression of AKR1B1 in both compartments and BMI, waist circumference as well as HOMAir index (p≤0.05 for all). Conclusion PGF2α release by omental mature adipocytes is increased in abdominally obese women. Moreover, COX-2 expression and PGF2α release is particularly responsive to

  18. Variation in plasma concentrations of oestradiol-17 beta and their relationship to those of progesterone, 13,14-dihydro-15-keto-prostaglandin F-2 alpha and oxytocin across pregnancy and at parturition in pony mares.

    PubMed

    Haluska, G J; Currie, W B

    1988-11-01

    Concentrations of plasma progesterone were similar to values reported in the literature except that a significant decrease in progesterone during the last day, but before parturition, was detected by systematic, high-intensity blood sampling. Mean concentrations of oestradiol-17 beta increased sharply and significantly, plateaued for 132.8 +/- 1.5 days (mean +/- s.e.m., N = 9), then declined sharply in each mare. There was obvious variation between the mares in when these increases and decreases in oestradiol-17 beta occurred, with the events being related closely to ambient photoperiod conditions rather than to the stage of pregnancy. Concentration of 13,14-dihydro-15-keto-prostaglandin F-2 alpha (PGFM) remained at low levels (less than 400 pg/ml) until Day 200 then increased to peak pregnancy levels (greater than 2000 pg/ml) by Day 300 and remained at this value until parturition. The concentrations of oxytocin remained basal (less than 15 microU/ml) throughout pregnancy and increased only at the beginning of the expulsive stage of labour. There was an increase, although not statistically significant, in the relative concentrations of oestradiol-17 beta to progesterone beginning 3 days before parturition, with the highest value of the ratio occurring at fetal delivery. Far more striking were acute changes in PGFM and oxytocin during parturition. Maximal concentrations of PGFM (approximately 30 ng/ml) and oxytocin (greater than 200 microU/ml) were measured between rupture of the chorioallantois and the completion of delivery. Closely timed samples from one animal showed that oxytocin increased (more than 10 standard deviations of the mean levels during late pregnancy for this animal) before any change in PGFM. In another dystocic mare, both oxytocin and PGFM peaked in the initial stages of delivery but only oxytocin remained elevated until the dystocia was remedied. The results suggest that an abrupt increase in oxytocin secretion precipitates the expulsive phase

  19. Influence of maternal and service-sire breed on serum progesterone and estrogen before calving and plasma 13,14-dihydro-15-keto-prostaglandin F2 alpha after calving.

    PubMed

    Lammoglia, M A; Holloway, J W; Lewis, A W; Neuendorff, D A; Randel, R D

    1995-04-01

    Effects of breed of service sire and cow on birth weight and prepartum and postpartum endocrine function were studied in multiparous Brahman (n = 20) and Angus (n = 20) cows bred to Brahman or Angus bulls. Before calving, blood samples were collected on d 34 to 28, 27 to 21, 20 to 14, and 13 to 7, and after calving, samples were collected from d 0 to 7. Progesterone (P4), estrogen (E2), and 13,14-dihydro-15-keto-prostaglandin F2 alpha (PGFM) were quantified with RIA. Calves born to Brahman were smaller (P < .05) than calves born to Angus cows. Prepartum concentrations of P4 were greater in Angus cows and decreased more rapidly near parturition than in Brahman cows (breed of dam x period; P < .03). Cows bearing bull calves had greater concentrations of P4 on d 20 to 14 before calving than cows bearing heifer calves (sex of calf x period; P < .04). Prepartum E2 was influenced (P < .05) by the breed of dam x breed of sire x period interaction. The ratio of P4:E2 tended to decrease more in Angus than in Brahman cows near parturition (breed of dam x period; P < .09). Postpartum PGFM tended to be influenced (P < .08) by breed of dam x breed of sire; from d 3 to 5, Brahman cows bred to Angus bulls tended (P < .08) to have greater PGFM than Brahman cows bred to Brahman bulls or than Angus cows bred to Brahman or Angus bulls.2+ f1p4 PMID:7628961

  20. Enzymatic formation of prostamide F2alpha from anandamide involves a newly identified intermediate metabolite, prostamide H2.

    PubMed

    Yang, Wu; Ni, Jinsong; Woodward, David F; Tang-Liu, Diane D-S; Ling, Kah-Hiing John

    2005-12-01

    Prostaglandin F2alpha 1-ethanolamide (prostamide F2alpha) is a potent ocular hypotensive agent in animals and represents a new class of fatty acid amide compounds. Accumulated evidence indicated that anandamide, an endogenous bioactive ligand for cannabinoid receptors, may serve as a common substrate to produce all prostamides, including prostamide F2alpha. After incubation of anandamide with cyclooxygenase 2 (COX-2), the reaction mixture was profiled by HPLC and an intermediate metabolite was discovered and characterized as a cyclic endoperoxide ethanolamide using HPLC-tandem mass spectrometry. Formation of prostamide F2alpha was also demonstrated when the intermediate metabolite was isolated and incubated with prostaglandin F synthase (PGF synthase). These results suggest that the biosynthesis of prostamide F2alpha proceeds in two consecutive steps: oxidation of anandamide to form an endoperoxide intermediate by COX-2, and reduction of the endoperoxide intermediate to form prostamide F2alpha by PGF synthase. This endoperoxide ethanolamide intermediate has been proposed as prostamide H2. PMID:16150817

  1. Effect of 8-isoprostaglandin F2alpha on the newborn rat pulmonary arterial muscle and endothelium.

    PubMed

    Belik, J; Jankov, R P; Pan, J; Yi, M; Pace-Asciak, C R; Tanswell, A K

    2003-11-01

    8-Isoprostaglandin F2alpha (8-iso-PGF2alpha) is a bioactive lipid peroxidation product that is a vasoconstrictor at high concentrations. Paradoxically, at lower, and possibly physiological, concentrations, it is a pulmonary vascular muscle's relaxant. Its effects on newborn pulmonary vasculature are unknown. We hypothesized that the pulmonary arterial 8-iso-PGF2alpha responses may be developmentally regulated. Therefore, the purpose of this study was to evaluate and compare 8-iso-PGF2alpha effects between 1- and 2-wk-old newborn and adult rat isolated intrapulmonary arteries (100 microm) mounted on a myograph. Force after 8-iso-PGF2alpha stimulation was greatest in the adult (P < 0.01). In newborns, force was significantly increased by the nitric oxide (NO) synthase inhibitor NG-nitro-l-arginine methyl ester (l-NAME) (P < 0.01) and was suppressed by blockade of the thromboxane (Tx) A2 receptor. Whereas 8-iso-PGF2alpha induced a significant dose-dependent relaxation of adult precontracted vessels in the presence of a TxA2 mimetic (U-46619; 1 microM), contraction was observed in the 1-wk-old rat. This 8-iso-PGF2alpha-induced contraction was abolished by endothelium removal and l-NAME and was attenuated by the cyclooxygenase inhibitor ibuprofen. In the presence of a TxA2/prostaglandin H2 receptor blocker, 8-iso-PGF2alpha induced NO-mediated relaxation, the magnitude of which was greater in the newborn, compared with the adult (P < 0.01). When exposed to 8-iso-PGF2alpha in vitro, only the newborn lung secreted TxB2. We conclude that, in contrast to its relaxant effect in the adult, 8-iso-PGF2alpha induces contraction of the pulmonary arteries in the early postnatal period, which is likely to be mediated by endothelium-derived TxA2. This phenomenon may contribute to the maintenance of a higher pulmonary vascular resistance in the early postnatal period. PMID:12857766

  2. The current status of prostaglandins as abortifacients.

    PubMed

    Brenner, W E

    1975-10-01

    The present use and potential uses of prostaglandins as abortifacients are summarized. Pertinent history, chemistry, prostaglandins' possible role in physiologic and pathologic processes and pharmacologic actions are discussed. The results of natural prostaglandins and their analogues by systemic and intrauterine administration for the purposes of postcoital contraception, menstrual regulation, first- and second-trimester abortion, preoperative dilation of the cervix, and delivery of patients with death in utero are presented. The only approved method of induction of abortion with prostaglandins, prostaglandin F2alpha by the intra-amniotic route for the induction of midtrimester abortion, is evaluated and compared to other methods of midtrimester abortion. It was concluded that: (1) the present use of prostaglandins is an important addition to the obstetrician's armamentarium, (2) more effective and/or convenient methods that are useful in patients over a wider gestational age appear to have been defined, and (3) the routine use of prostaglandins for postcoital contraception, menstrual regulation, and first-trimester abortion will require the development of analogues that are more specific as to their abortifacient actions than the natural prostaglandins and/or the development of improved delivery systems. PMID:810025

  3. Steroidal regulation of uterine resistance to bacterial infection in livestock

    PubMed Central

    Lewis, Gregory S

    2003-01-01

    Postpartum uterine infections reduce reproductive efficiency and have significant animal welfare and economic consequences. Postpartum uterine infections are classified as nonspecific, but Arcanobacterium pyogenes and Escherichia coli are usually associated with them in cattle and sheep. Pyometra is the most common type of uterine infection in dairy cattle, and it is detected almost exclusively in cows with active corpora lutea. Luteal progesterone typically down-regulates uterine immune functions and prevents the uterus from resisting infections. Progesterone also can down-regulate uterine eicosanoid synthesis. This seems to be a critical event in the onset of uterine infections, because eicosanoids can up-regulate immune cell functions in vitro. In addition, exogenous prostaglandin F2 alpha stimulates uterine secretion of prostaglandin F2 alpha and enhances immune functions in vivo. Thus, one may hypothesize that eicosanoids can override the negative effects of progesterone and that the up-regulatory effects of exogenous prostaglandin F2 alpha allow the uterus to resolve an infection, regardless of progesterone concentrations. Based on the results of studies to test that hypothesis, cows, sheep, and pigs in various physiological statuses are resistant to intrauterine infusions of Arcanobacterium pyogenes and Escherichia coli, unless progesterone concentrations are increased. In sheep and pigs, exogenous prostaglandin F2 alpha stimulates uterine production of prostaglandin F2 alpha and allows the uterus to resolve Arcanobacterium pyogenes-Escherichia coli-induced infections, even when progesterone is maintained at luteal phase concentrations before and after treatment. Prostaglandin F2 alpha is a proinflammatory molecule that stimulates the production of various proinflammatory cytokines, and it may enhance uterine production of leukotriene B4. Proinflammatory cytokines and leukotriene B4 enhance phagocytosis and lymphocyte functions. Even though there are clear

  4. Use of prostaglandin F2 alpha as a postpartum reproductive management tool for lactating dairy cows.

    PubMed

    Pankowski, J W; Galton, D M; Erb, H N; Guard, C L; Gröhn, Y T

    1995-07-01

    This study compared three programs for reproductive management of the postpartum period for reproductive performance and net economic benefit within three dairy herds (n = 1624 cows). Cows on one program received PGF alpha injection at 25 to 32 d postpartum for reproductive therapy, and cows on a second program received additional PGF2 alpha at 39 to 46 d postpartum for synchronization of estrus. These programs were compared with a postpartum program of rectal palpation based on veterinary intervention. Survival analysis indicated that cows receiving PGF2 alpha for reproductive therapy and synchronization of estrus had an 11% higher rate of first AI and 10% higher rate of pregnancy than did cows receiving the rectal palpation. No differences existed between the cows receiving rectal palpation and those receiving the PGF2 alpha. Because overall conception rates and conception rates at first AI did not differ among programs, the improved reproductive performance of cows receiving PGF2 alpha for both therapy and synchronization may be attributed to greater synchronization of estrus, which resulted in improved estrus detection. A partial budget indicated that the PGF2 alpha programs were less expensive than the rectal palpation program. When PGF2 alpha was used for postpartum reproductive therapy and synchronization of estrus, reproductive performance and net economic benefit were increased compared with those of the other programs. PMID:7593841

  5. Estrus synchronization of lactating dairy cows with GnRH, progesterone, and prostaglandin F2 alpha.

    PubMed

    Xu, Z Z; Burton, L J

    2000-03-01

    The reproductive performance of synchronized cows was compared with that of nonsynchronized cows. In trial 1, cyclic cows in five seasonal herds were randomly divided into two groups. Cows in one group (n = 515) were treated with a GnRH agonist and an intravaginal progesterone device, followed in 7 d by a PGF2 alpha injection, and the device was removed 1 d after PGF2 alpha. Cows in the other group (n = 512) did not receive any treatment and acted as control. In trial 2, the treatments were similar to those used in trial 1 except that the progesterone device was removed at the time of PGF2 alpha injection (synchronized: n = 516; control: n = 512). The estrus synchronization rate was 92.8% in trial 1 and 92.2% in trial 2. Conception rate to first artificial insemination (AI) was lower for synchronized cows than for control cows in trial 1 (56.5 vs. 62.7%), but similar in trial 2 (64.6 vs. 63.3%). Across both trials, the pregnancy rate during the AI breeding period was greater for the synchronized cows (85.6%) than for the control cows (81.2%). The synchronization treatment reduced the interval from start of the breeding season to conception for cows conceiving by AI (8.9 vs. 14.8 d) or by AI or natural mating (14.1 vs. 21.6 d). The synchronization protocol used in trial 2 achieved better conception rate than that used in trial 1, but the precision of estrus was less in trial 2 than in trial 1. PMID:10750104

  6. Prostaglandin signaling regulates ciliogenesis by modulating intraflagellar transport

    PubMed Central

    Jin, Daqing; Ni, Terri T.; Sun, Jianjian; Wan, Haiyan; Amack, Jeffrey D.; Yu, Guangju; Fleming, Jonathan; Chiang, Chin; Li, Wenyan; Papierniak, Anna; Cheepala, Satish; Conseil, Gwenaëlle; Cole, Susan P.C.; Zhou, Bin; Drummond, Iain A.; Schuetz, John D.; Malicki, Jarema; Zhong, Tao P.

    2014-01-01

    Cilia are microtubule-based organelles that mediate signal transduction in a variety of tissues. Despite their importance, the signaling cascades that regulate cilia formation remain incompletely understood. Here we report that prostaglandin signaling affects ciliogenesis by regulating anterograde intraflagellar transport (IFT). Zebrafish leakytail (lkt) mutants display ciliogenesis defects, and lkt locus encodes an ATP-binding cassette transporter (ABCC4). We show that Lkt/ABCC4 localizes to the cell membrane and exports prostaglandin E2 (PGE2), a function that is abrogated by the Lkt/ABCC4T804M mutant. PGE2 synthesis enzyme Cyclooxygenase-1 and its receptor, EP4, which localizes to the cilium and activates cAMP-mediated signaling cascade, are required for cilia formation and elongation. Importantly, PGE2 signaling increases anterograde but not retrograde velocity of IFT and promotes ciliogenesis in mammalian cells. These findings lead us to propose that Lkt/ABCC4-mediated PGE2 signaling acts through a ciliary G-protein-coupled receptor, EP4, to upregulate cAMP synthesis and increase anterograde IFT, thereby promoting ciliogenesis. PMID:25173977

  7. Conceptus-derived prostaglandins regulate endometrial function in sheep.

    PubMed

    Dorniak, Piotr; Bazer, Fuller W; Wu, Guoyao; Spencer, Thomas E

    2012-07-01

    In sheep, the trophectoderm of the elongating conceptus secretes interferon tau (IFNT) and prostaglandins (PGE2, PGF2alpha, PGI2). The PGs are derived from PG synthase 2 (PTGS2), and inhibition of PTGS2 in utero prevents conceptus elongation. IFNT increases expression of many genes in the endometrial epithelia that regulate conceptus elongation. This study tested the hypothesis that PGs secreted by the conceptus regulate endometrial functions that govern conceptus elongation. Cyclic ewes received intrauterine infusions of control vehicle or early pregnancy levels of IFNT, PGE2, PGF2alpha, or PGI2 from Days 10-14 postestrus. Expression levels of endometrial GRP, IGFBP1, and LGALS15, whose products stimulate trophectoderm cell migration and attachment, were increased by PGE2, PGI2, and IFNT. All PGs and IFNT increased expression of the HEXB protease gene, but only IFNT increased the CST6 protease inhibitor gene. Differential effects of PGs were observed for expression of the CTSL protease gene and its inhibitor, CST3. IFNT, PGF2alpha, and PGI2 increased ANGPTL3 expression, but only IFNT and PGE2 increased HIF1A expression, both of which regulate angiogenesis. For glucose transporters, IFNT and all PGs increased SLC2A1 expression, but only PGs increased SLC2A5 expression, whereas endometrial SLC2A12 and SLC5A1 expression levels were increased by IFNT, PGE2, and PGF2alpha. Infusions of all PGs and IFNT increased the amino acid transporter SLC1A5, but only IFNT increased SLC7A2 expression. In the uterine lumen, only IFNT increased glucose levels, and only PGE2 and PGF2alpha increased total amino acids. These results indicate that PGs and IFNT from the conceptus coordinately regulate endometrial functions important for growth and development of the conceptus during the peri-implantation period of pregnancy. PMID:22517622

  8. Metabolic fate of radiolabeled prostaglandin D2 in a normal human male volunteer

    SciTech Connect

    Liston, T.E.; Roberts, L.J. 2d.

    1985-10-25

    50 microCi of (TH)prostaglandin D2 tracer (100 Ci/mmol) was infused intravenously into a normal human male volunteer. 75% of the infused radioactivity was excreted into the urine within 5 h. This urine was added to urine obtained from two mastocytosis patients with marked overproduction of prostaglandin D2. Radiolabeled prostaglandin D2 urinary metabolites were chromatographically isolated and purified and subsequently identified by gas chromatography-mass spectrometry. 25 metabolites were identified. 23 of these compounds comprising 37% of the recovered radioactivity had prostaglandin F-ring structures, and only two metabolites comprising 2.7% of the recovered radioactivity retained the prostaglandin D-ring structure. The single most abundant metabolite identified was 9,11-dihydroxy-15-oxo-2,3,18,19-tetranorprost-5-ene-1,20-dioic acid which was isolated in a tricyclic form as a result of formation of a lower side chain hemiketal followed by lactonization of the terminal carboxyl and the hemiketal hydroxyl. Different isomeric forms of several prostaglandin F-ring metabolites were identified. An isomer of prostaglandin F2 alpha was also excreted intact into the urine as a metabolite of prostaglandin D2. 15 PGF-ring compounds were treated with n-butylboronic acid and 13 failed to form a boronate derivative, suggesting that the orientation of the hydroxyl group at C-11 in these 13 metabolites is beta. This study documents that prostaglandin D2 is metabolized to prostaglandin F-ring metabolites in vivo in humans. These results also bring into question the accuracy of quantifying prostaglandin F2 alpha metabolites as a specific index of endogenous prostaglandin F2 alpha biosynthesis, as well as quantifying urinary prostaglandin F2 alpha as an accurate index of renal production of prostaglandin F2 alpha.

  9. Generation of 8-epi-prostaglandin F(2alpha) in isolated rat kidney glomeruli by a radical-independent mechanism.

    PubMed

    Klein, T; Neuhaus, K; Reutter, F; Nüsing, R M

    2001-07-01

    Isoprostanes comprise a group of free radical-catalyzed products of arachidonic acid. However, there is recent evidence pointing towards an enzyme-dependent formation of isoprostanes. With the use of isolated rat glomeruli we addressed the mechanisms of isoprostane generation. Synthesis of prostanoids and isoprostanes, including 8-epi-PGF(2alpha), was studied under conditions favouring radical formation. Cultured glomeruli formed different prostanoids including 8-epi-PGF(2alpha). Upon LPS challenge cyclo-oxygenase (COX)-2 expression was enhanced, and this was paralleled by a 2 - 9-fold increase in prostanoid formation, including isoprostanes. Addition of COX-isoform unselective inhibitors (diclofenac, indomethacin) or a selective inhibitor (NS-398) suppressed the synthesis of prostanoids, 8-epi-PGF(2alpha) and total isoprostane fraction; however, inhibition of the latter was less pronounced. Antioxidants such as butylated hydroxytoluene (BHT), nordihydroguaiaretic acid (NDGA), or dimethylurea exhibited an only minimal inhibitory effect on 8-epi-PGF(2alpha) synthesis. Moreover, ROS-generating drugs (menadione, methylviologen) or NADPH-driven radical formation were unable to cause the generation of significant amounts of 8-epi-PGF(2alpha) by rat glomeruli. In contrast, the total isoprostane fraction could be increased by menadione addition. These data provide further evidence for a radical-independent, but COX-dependent formation of 8-epi-PGF(2alpha) in renal tissue. Regarding the other isoprostanes, both radicals and COX enzymes contribute to their formation. Based on our data we assume that elevated release of vasoactive 8-epi-PGF(2alpha) has to be expected under conditions when the prostanoid system in the kidney is stimulated, e.g. under inflammatory conditions. Regarding renal oxidative injuries, the usefulness of 8-epi-PGF(2alpha) as a representative marker molecule of oxidative stress has to be questioned. PMID:11429387

  10. Intrauterine pregnancy after treatment of tubal pregnancy with local and systemic prostaglandins in a patient with a single oviduct.

    PubMed

    Hönigl, W; Lang, P F; Weiss, P A; Winter, R

    1992-04-01

    A spontaneous intrauterine pregnancy occurred after instillation of prostaglandin-F2 alpha into the solitary tube and systemic prostaglandin administration for treatment of an ectopic gestation. This is the first unequivocal proof of intact function of the affected tube after non-surgical treatment of a tubal pregnancy with prostaglandins. PMID:1325989

  11. Anorectic activity of prostaglandin precursors.

    PubMed Central

    Doggett, N S; Jawaharlal, K

    1977-01-01

    1 Intraperitoneal and intragastric (i.g.) administration of prostaglandin precursors arachidonic (2 mg, 15 mg/kg, i.p; 30 mg/kg i.g.), linolenic (100 mg/kg i.p.; 200 mg/kg, i.g.) and linoleic (15, 100 mg/kg, i.p.; 100 mg/kg, i.g.) acids to 22 h food-deprived rats inhibits food intake. 2 This anorexia is similar to that induced by prostaglandin F2alpha (1 mg/kg, i.p.). 3 At anorectic doses these fatty acids do not cause pyrexia, in fact arachidonic acid causes hypothermia. 4 Prior treatment with indomethacin (15 mg/kg) and paracetamol (50 mg/kg) specifically reverses the anorexia and the behavioural satiety induced by the three fatty acids, while not affecting prostaglandin F2alpha-induced suppression of food intake. 5 Results of the present experiments suggest that both physiological and pharmacological modification of appetite could be brought about through an effect on prostaglandin generating systems. PMID:890209

  12. Dioscorea japonica extract down-regulates prostaglandin E2 synthetic pathway and induces apoptosis in lung cancer cells

    PubMed Central

    Suzuki-Yamamoto, Toshiko; Tanaka, Sayuri; Tsukayama, Izumi; Takafuji, Miki; Hanada, Takae; Arakawa, Toshiya; Kawakami, Yuki; Kimoto, Masumi; Takahashi, Yoshitaka

    2014-01-01

    Prostaglandin E2 plays a role in an array of pathophysiological responses, including inflammation, carcinogenesis and so on. Prostaglandin E2 is synthesized from arachidonic acid by the enzymes cyclooxygenase and prostaglandin E synthase. In some pathological conditions, the isozymes cyclooxygenase-2 and microsomal prostaglandin E synthase-1 are transiently induced, leading to prostaglandin E2 overproduction. The present study showed that Dioscorea japonica extract suppresses mRNA expression of cyclooxygenase-2 and microsomal prostaglandin E synthase-1 in human non-small-cell lung carcinoma A549 cells in a dose-dependent manner. The suppressive effects of Dioscorea japonica extract on the expression of cyclooxygenase-2 and microsomal prostaglandin E synthase-1 were confirmed by Western blotting, cyclooxygenase activity and prostaglandin E2 production. Dioscorea japonica extract induced the translocation of nuclear factor-κB from the nucleus to the cytosol and inhibited the activity of the cyclooxygenase-2 promoter. Furthermore Dioscorea japonica extract suppressed the expression of the anti-apoptotic factor B-cell chronic lymphocytic leukemia/lymphoma 2 and enhanced apoptotic terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling-positive intensity in A549 cells. These results suggest that Dioscorea japonica extract suppresses the expression of cyclooxygenase-2 and microsomal prostaglandin E synthase-1, with the regulation of the transcriptional activity of cyclooxygenase-2, and induces apoptosis in cancer cells. Thus, Dioscorea japonica may contribute to the prevention of prostaglandin E2-mediated pathophysiological responses such as carcinogenesis and inflammation. PMID:25411520

  13. Prostaglandin F2α receptor (FP) signaling regulates Bmp signaling and promotes chondrocyte differentiation

    PubMed Central

    Kim, Joohwee; Shim, Minsub

    2015-01-01

    Prostaglandins are a group of lipid signaling molecules involved in various physiological processes. In addition, prostaglandins have been implicated in the development and progression of diseases including cancer, cardiovascular disease, and arthritis. Prostaglandins exert their effects through the activation of specific G protein-coupled receptors (GPCRs). In this report, we examined the role of prostaglandin F2α receptor (FP) signaling as a regulator of chondrocyte differentiation. We found that FP expression was dramatically induced during the differentiation of chondrocytes and was up-regulated in cartilages. Forced expression of FP in ATDC5 chondrogenic cell line resulted in the increased expression of differentiation-related genes and increased synthesis of the extracellular matrix (ECM) regardless of the presence of insulin. Similarly, PGF2α treatment induced the expression of chondrogenic marker genes. In contrast, knockdown of endogenous FP expression suppressed the expression of chondrocyte marker genes and ECM synthesis. Organ culture of cartilage rudiments revealed that PGF2α induces chondrocyte hypertrophy. Additionally, FP overexpression increased the levels of Bmp-6, phospho-Smad1/5, and Bmpr1a, while knockdown of FP reduced expression of those genes. These results demonstrate that up-regulation of FP expression plays an important role in chondrocyte differentiation and modulates Bmp signaling. PMID:25499765

  14. Multifactorial regulation of prostaglandin synthesis in preovulatory goldfish ovarian follicles.

    PubMed

    Kellner, R G; Van der Kraak, G

    1992-04-01

    Goldfish preovulatory ovarian follicles (prior to germinal vesicle breakdown) were utilized for studies investigating the actions of activators of different signal transduction pathways on prostaglandin (PG) production. The protein kinase C (PKC) activators phorbol 12-myristate 13-acetate (PMA; 100-400 nM), 1-oleoyl-2-acetylglycerol (5 and 25 micrograms/ml), and 1,2-dioctanoylglycerol (10 and 50 micrograms/ml) stimulated PGE production; the inactive phorbol 4 alpha-phorbol didecanoate, which does not activate PKC, had no effect. Calcium ionophore A23187 (0.25-4.0 microM) stimulated PGE production and acted in a synergistic manner with activators of PKC. Although produced in lower amounts than PGE, PGF was stimulated by PMA and A23187. The direct activator of phospholipase A2, melittin (0.1-1.0 microM), stimulated a dose-related increase in PGE production, whereas chloroquine (100 microM), a putative inhibitor of phospholipase A2, blocked basal and PMA + A23187-stimulated PGE production. Several drugs known to elevate intracellular levels of cAMP including the phosphodiesterase inhibitor 3-isobutyl-1-methylxanthine (0.1-1.0 mM), forskolin (10 microM), and dibutyryl cAMP (dbcAMP; 5 mM) attenuate PMA + A23187-stimulated PGE production. Melittin-stimulated production of PGE was inhibited by dbcAMP, suggesting that the action of cAMP was distal to the activation of phospholipase A2. In summary, these studies demonstrate that activation of PKC and elevation of intracellular calcium levels stimulate PG production, in part, through activation of phospholipase A2. The adenylate cyclase/cAMP signalling pathway is inhibitory to PG production by goldfish ovarian follicles. PMID:1315582

  15. Prostaglandins induce early growth response 1 transcription factor mediated microsomal prostaglandin E2 synthase up-regulation for colorectal cancer progression

    PubMed Central

    Stamatakis, Konstantinos; Jimenez-Martinez, Marta; Jimenez-Segovia, Alba; Chico-Calero, Isabel; Conde, Elisa; Galán-Martínez, Javier; Ruiz, Julia; Pascual, Alejandro; Barrocal, Beatriz; López-Pérez, Ricardo; García-Bermejo, María Laura; Fresno, Manuel

    2015-01-01

    Cyclooxygenase2 (COX2) has been associated with cell growth, invasiveness, tumor progression and metastasis of colorectal carcinomas. However, the downstream prostaglandin (PG)-PG receptor pathway involved in these effects is poorly characterized. We studied the PG-pathway in gene expression databases and we found that PTGS2 (prostaglandin G/H synthase and cyclooxygenase) and PTGES (prostaglandin E synthase) are co-expressed in human colorectal tumors. Moreover, we detected that COX2 and microsomal Prostaglandin E2 synthase 1 (mPGES1) proteins are both up-regulated in colorectal human tumor biopsies. Using colon carcinoma cell cultures we found that COX2 overexpression significantly increased mPGES1 mRNA and protein. This up-regulation was due to an increase in early growth response 1 (EGR1) levels and its transcriptional activity. EGR1 was induced by COX2-generated PGF2α. A PGF2α receptor antagonist, or EGR1 silencing, inhibited the mPGES1 induction by COX2 overexpression. Moreover, using immunodeficient mice, we also demonstrated that both COX2- and mPGES1-overexpressing carcinoma cells were more efficient forming tumors. Our results describe for the first time the molecular pathway correlating PTGS2 and PTGES in colon cancer progression. We demonstrated that in this pathway mPGES1 is induced by COX2 overexpression, via autocrine PGs release, likely PGF2α, through an EGR1-dependent mechanism. This signaling provides a molecular explanation to PTGS2 and PTGES association and contribute to colon cancer advance, pointing out novel potential therapeutic targets in this oncological context. PMID:26498686

  16. Prostaglandins of the E-series inhibit connective tissue proliferation in the liver wound of the rat.

    PubMed

    Arend, A; Aunapuu, M; Masso, R; Selstam, G

    2005-03-01

    The present study was undertaken to relate wound healing of an internal organ to prostaglandins of the E and F series. A small liver wound was induced by a galvanic cauter via the abdominal route under general anesthesia and prostaglandin E1, E2 and F2alpha were injected twice daily at a dose of 250 microg/kg. Proliferation of the connective tissue in the liver wound was estimated morphometrically 6 days after liver wound infliction. Levels of prostaglandins E2 and F2alpha were measured in the liver wound as well as in normal liver tissue from adjacent lobes using radioimmunoassay. The results show that exogenous prostaglandins of the E-series suppress connective tissue proliferation. Three minutes after the last prostaglandin E2 injection, high prostaglandin concentrations were measured both in the liver wound and in the liver tissue of the adjacent lobe. Prostaglandin F2alpha injections had no effect on wound healing. We believe that the rat thermic liver wound model can be used for different studies on wound healing mechanisms and that prostaglandins of the E-series are involved in wound healing in the specific time period studied. PMID:15835401

  17. Up-regulation of cyclooxygenase-2 by product-prostaglandin E2

    NASA Technical Reports Server (NTRS)

    Tjandrawinata, R. R.; Hughes-Fulford, M.

    1997-01-01

    The development of prostate cancer has been linked to high level of dietary fat intake. Our laboratory investigates the connection between cancer cell growth and fatty acid products. Studying human prostatic carcinoma PC-3 cells, we found that prostaglandin E2 (PGE2) increased cell growth and up-regulated the gene expression of its own synthesizing enzyme, cyclooxygenase-2 (COX-2). PGE2 increased COX-2 mRNA expression dose-dependently with the highest levels of stimulation seen at the 3-hour period following PGE2 addition. The NSAID flurbiprofen (5 microM), in the presence of exogenous PGE2, inhibited the up-regulation of COX-2 mRNA and cell growth. These data suggest that the levels of local intracellular PGE2 play a major role in the growth of prostate cancer cells through an activation of COX-2 gene expression.

  18. Inhibition of protein translation as a novel mechanism for prostaglandin E2 regulation of cell functions

    PubMed Central

    Okunishi, Katsuhide; DeGraaf, Angela J.; Zasłona, Zbigniew; Peters-Golden, Marc

    2014-01-01

    Prostaglandin E2 (PGE2) regulates numerous biological processes by modulating transcriptional activation, epigenetic control, proteolysis, and secretion of various proteins. Scar formation depends on fibroblast elaboration of matrix proteins such as collagen, and this process is strongly suppressed by PGE2 through activation of cAMP-dependent protein kinase A (PKA). However, the actual mechanism by which PGE2-PKA signaling inhibits collagen expression in fibroblasts has never been delineated, and that was the objective of this study. PGE2 unexpectedly induced a rapid reduction in procollagen I protein expression in adult lung fibroblasts, with a half-maximum effect at 1.5 h. This effect reflected its inhibition of translation rather than transcription. Global protein synthesis was also inhibited by PGE2. This action was mediated by PKA and involved both activation of ribosomal protein (rpS6) and suppression of mammalian target of rapamycin (mTOR). Similar effects of PGE2 were demonstrated in mouse peritoneal macrophages (PMs). These findings identify inhibition of translation as a new mechanism by which PGE2 regulates cellular function and a novel example of translational inhibition mediated by opposing actions on two distinct translational control pathways. Translational inhibition would be expected to contribute to dynamic alterations in cell function that accompany the changing PGE2 levels observed in disease states and with various pharmacotherapies.—Okunishi K., DeGraaf, A. J., Zasłona, Z., Peters-Golden, M. Inhibition of protein translation as a novel mechanism for prostaglandin E2 regulation of cell functions. PMID:24072780

  19. Treatment of noncyclic lactating dairy cows with progesterone and estradiol or with progesterone, GnRH, prostaglandin F2 alpha, and estradiol.

    PubMed

    Xu, Z Z; Burton, L J; McDougall, S; Jolly, P D

    2000-03-01

    The efficacy of two programs for treating noncyclic cows was compared. In trial 1, 478 cows in five herds were randomly divided into two groups. Cows in one group (C group) were treated with an intravaginal progesterone device for 8 d followed in 48 h by 1 mg of estradiol benzoate to cows that had not been detected in estrus since device removal. Those in the other group (CGP group) were treated with progesterone and estradiol as for the C group plus 10 micrograms of a GnRH agonist (buserelin) at device insertion and 25 mg of PGF2 alpha 7 d after device insertion. In trial 2 with 729 cows in nine herds, the treatments were similar to those in trial 1 except that the duration of progesterone treatment was 7 d. No significant difference was found between trials and results from both trials were combined. Compared with C group cows, CGP group cows had a greater estrous response rate (93.2 vs. 89.1%), a greater conception rate to first artificial insemination (AI, 47.1 vs. 29.4%), marginally lower conception rate to second AI (52.9 vs. 59.7%), lower nonpregnancy rate (8.3 vs. 11.1%), and shorter intervals from the start of breeding to conception by AI (9.8 vs. 15.3 d) or by AI or natural mating (21.6 vs. 26.3 d). The treatment protocol used for the CGP group achieved better reproductive performance than that used for the C group. PMID:10750103

  20. Estrus synchronization and fertility in post-partum dairy cattle after administration of human chorionic gonadotrophin (HCG) and prostaglandin F2 alpha analog.

    PubMed

    De Rensis, F; Allegri, M; Seidel, G E

    1999-07-15

    Human chorionic gonadotrophin (hCG) plus PGF2 alpha was compared with GnRH plus PGF2 alpha for estrus synchronization of dairy cows. There were 3 treatments: GnRH analog (Buserelin, 12.6 micrograms) plus PGF2 alpha analog (Cloprostenol, 150 micrograms) 6 d later (GnRH + PGF[Day 6]); hCG (2000 IU) plus PGF2 alpha 9 d later (hCG + PGF[Day 9]); and hCG plus PGF2 alpha 6 d later (hCG + PGF[Day 6]). Treatment occurred either Days 55 to 90 or Days 91 to 135 post partum. For responses during the first 10 d after PGF2 alpha administration, estrus synchronization (P = 0.24), efficacy (percentage of treated pregnant; P = 0.20) and conception (percentage of inseminated pregnant; P = 0.23) rates were not different among the 3 treatments. Cows treated between Days 55 and 90 had a higher rate (P < 0.05) of detected estrus during this period (69% for GnRH + PG [Day 6], 70% for hCG + PGF[Day 9] and 72% for hCG + PGF[Day 6]) compared with cows treated between Days 91 and 135 (52% for GnRH + PGF[Day 6], 50% for hCG + PGF[Day 9] and 57% for hCG + PGF[Day 6]). Efficacy of treatment was higher (P < 0.05) in animals treated between Days 55 and 90 (54% for GnRH + PGF[Day 6], 56% for hCG + PGF[Day 9] and 63% for hCG + PGF [Day 6]) compared to animals treated between Days 91 and 135 (36% for GnRH + PGF[Day 6], 35% for hCG + PGF[Day 9] and 47% for hCG + PGF[Day 6]). There were no significant differences in conception between Days 51 and 90 and Days 91 and 135. The interval between parturition-first AI with conception was significantly (P < 0.001) shorter in GnRH + PGF (Day 6; 106 d), hCG + PGF (Day 9; 109 d) and hCG + PGF (Day 6; 103 d) treated cattle than in 106 untreated animals (136 d). Thus, GnRH plus PGF2 alpha or hCG plus PGF2 alpha treatments elicited similar effects in estrus synchronization, treatment efficacy, and conception rate in post-partum dairy cows. PMID:10734393

  1. Efficacy of induction of luteolysis in superovulated cows is dependent on time of prostaglandin F2alpha analog treatment: effects on plasma progesterone and luteinizing hormone profiles.

    PubMed

    Viana, J H M; Vargas, M S B; Siqueira, L G B; Camargo, L S A; Figueiredo, A C S; Fernandes, C A C; Palhao, M P

    2016-09-01

    The objectives were to (1) evaluate the effectiveness of induction of luteolysis in superovulated (SOV) cows at two distinct time points after embryo flushing; and (2) compare the pattern of LH release after treatment with PGF in cows with single vs. multiple ovulations. In the first experiment, Holstein cows were SOV with 400 IU of FSH following standard procedures. Uterine flushing for embryo recovery was performed 7 days after artificial insemination (Day 0), and cows were randomly allocated into two groups to receive PGF (0.5-mg sodium cloprostenol, intramascular) either immediately after flushing (Day 7 group, N = 19) or 4 days later (Day 11 group, N = 20). Time of luteolysis was determined on the basis of plasma progesterone (P4) concentrations. There was no difference (P > 0.05) in plasma P4 before treatment between Day 7 and Day 11 groups. A decline in plasma P4 was observed 48 hours after PGF treatment in both the groups (P < 0.0001). In Day 11 cows, P4 continued to decrease thereafter, whereas Day 7 animals had no further reduction in plasma P4. Luteolysis (P4 < 1 ng/mL) occurred in all Day 11 cows. In the Day 7 group, however, luteolysis failure was observed for 11 of 19 cows (57.9%). In cows without luteolysis, plasma P4 increased after the initial PGF-induced decline. The second experiment compared luteolysis in (SOV, N = 6) vs. non-SOV (control, N = 8) cows. Both groups received a single PGF treatment on Day 11 after estrus, and luteolysis was monitored daily by ovarian ultrasonography and plasma P4 measurements. In addition, plasma LH was measured in blood samples taken every 20 minutes for 1 hour during five consecutive days after treatment. A similar percentage of reduction in P4 was observed in both groups 24 hours after treatment; however, SOV cows only reached plasma P4 values similar (P > 0.05) to controls 96 hours after treatment. There was no difference in initial LH values between SOV and controls (P > 0.05). The slower decrease in plasma P4 in the SOV group prevented an increase in LH for up to 96 hours after luteolysis induction, whereas LH values increased (P < 0.05) in controls 24 hours after treatment. In conclusion, (1) luteolysis may fail or be incomplete when PGF treatment is given on the day of uterine flushing (Day 7) in SOV cows; (2) induction of luteolysis 4 days later (Day 11) is effective, but the initial high-plasma P4 concentrations result in a slower slope of P4 decline to basal levels, and consequently, delayed increase in LH pulses. PMID:27118386

  2. Distinct Roles of Central and Peripheral Prostaglandin E2 and EP Subtypes in Blood Pressure Regulation

    PubMed Central

    Yang, Tianxin; Du, Yaomin

    2012-01-01

    Prostaglandin E2 (PGE2) is a major prostanoid with a wide variety of biological activities. PGE2 can influence blood pressure (BP) both positively and negatively. In particular, centrally administered PGE2 induces hypertension whereas systemic administration of PGE2 produces a hypotensive effect. These physiologically opposing effects are generated by the existence of multiple EP receptors, namely EP1–4, which are G protein-coupled receptors with distinct signaling properties. This review highlights the distinct roles of PGE2 in BP regulation and the involvement of specific EP receptor subtypes. American Journal of Hypertension, advance online publication 14 June 2012; doi:10.1038/ajh.2012.67 PMID:22695507

  3. Prostaglandin F{sub 2{alpha}} regulates cytokine responses of mast cells through the receptors for prostaglandin E

    SciTech Connect

    Kaneko, Izumi; Hishinuma, Takanori; Suzuki, Kaori; Owada, Yuji; Kitanaka, Noriko; Kondo, Hisatake; Goto, Junichi; Furukawa, Hiroshi; Ono, Masao

    2008-03-14

    There is an increasing body of evidence that prostanoids modulate mast cell functions and contribute to the development of allergic inflammation. The present study aimed to identify an undetermined function of prostaglandin (PG) F{sub 2{alpha}} in mast cell activation and the signaling mechanism involved in it. Simultaneous quantification of prostanoids by liquid chromatography/tandem mass spectrometry revealed the constitutive release of PGF{sub 2{alpha}}, thromboxane B{sub 2}, and 6-keto-PGF{sub 1{alpha}} from bone marrow-derived mast cells (BMMCs). Upon activation of BMMCs by lipopolysaccharide, the cytokine production in BMMCs was enhanced when the culture was supplemented with PGF{sub 2{alpha}}. However, F prostanoid receptor-a selective receptor for PGF{sub 2{alpha}}-was not detected in BMMCs. Further investigations performed using prostanoid receptor antagonists revealed an alternative mechanism wherein the receptors for PGE species-E prostanoid receptors-mediated the PGF{sub 2{alpha}} signal in BMMCs. The present study provides an insight into a novel function of PGF{sub 2{alpha}}, i.e., an autocrine accelerator for mast cell activation.

  4. Prostaglandin E{sub 2} regulates melanocyte dendrite formation through activation of PKC{zeta}

    SciTech Connect

    Scott, Glynis Fricke, Alex; Fender, Anne; McClelland, Lindy; Jacobs, Stacey

    2007-11-01

    Prostaglandins are lipid signaling intermediates released by keratinocytes in response to ultraviolet irradiation (UVR) in the skin. The main prostaglandin released following UVR is PGE{sub 2}, a ligand for 4 related G-protein-coupled receptors (EP{sub 1}, EP{sub 2}, EP{sub 3} and EP{sub 4}). Our previous work established that PGE{sub 2} stimulates melanocyte dendrite formation through activation of the EP{sub 1} and EP{sub 3} receptors. The purpose of the present report is to define the signaling intermediates involved in EP{sub 1}- and EP{sub 3}-dependent dendrite formation in human melanocytes. We recently showed that activation of the atypical PKC{zeta} isoform stimulates melanocyte dendricity in response to treatment with lysophosphatidylcholine. We therefore examined the potential contribution of PKC{zeta} activation on EP{sub 1}- and EP{sub 3}-dependent dendrite formation in melanocytes. Stimulation of the EP{sub 1} and EP{sub 3} receptors by selective agonists activated PKC{zeta}, and inhibition of PKC{zeta} activation abrogated EP{sub 1}- and EP{sub 3}-receptor-mediated melanocyte dendricity. Because of the importance of Rho-GTP binding proteins in the regulation of melanocyte dendricity, we also examined the effect of EP{sub 1} and EP{sub 3} receptor activation on Rac and Rho activity. Neither Rac nor Rho was activated upon treatment with EP{sub 1,3}-receptor agonists. We show that melanocytes express only the EP{sub 3A1} isoform, but not the EP{sub 3B} receptor isoform, previously associated with Rho activation, consistent with a lack of Rho stimulation by EP{sub 3} agonists. Our data suggest that PKC{zeta} activation plays a predominant role in regulation of PGE{sub 2}-dependent melanocyte dendricity.

  5. Influence of prostaglandins and adrenoceptor agonists on contractile activity in the human cervix at term.

    PubMed

    Bryman, I; Norström, A; Lindblom, B

    1986-04-01

    The influence of prostaglandins as well as adrenoceptor agonists and antagonists on contractile activity of isolated cervical smooth muscle from term pregnant women was studied. Prostaglandin E2 had an inhibitory effect at extremely low concentrations. Inhibition also was induced by prostaglandin F2 alpha, prostaglandin I2, and 6-keto-prostaglandin F1 alpha, but at considerably higher concentrations. Contractions evoked by noradrenaline or phenylephrine were blocked by the alpha-adrenoceptor antagonist phenoxybenzamine. The beta-adrenoceptor agonist terbutaline acted as an inhibitor, whereas isoprenaline in most cases stimulated contractile activity. The inhibitory action of prostaglandins and especially the high sensitivity to prostaglandin E2 point to a physiologic role of these compounds for cervical dilatation and retraction. A predominance of alpha-adrenoceptors might be of importance for the maintenance of cervical competence during pregnancy. PMID:2870450

  6. Prostaglandin ethanolamides (prostamides): in vitro pharmacology and metabolism.

    PubMed

    Matias, I; Chen, J; De Petrocellis, L; Bisogno, T; Ligresti, A; Fezza, F; Krauss, A H-P; Shi, L; Protzman, C E; Li, C; Liang, Y; Nieves, A L; Kedzie, K M; Burk, R M; Di Marzo, V; Woodward, D F

    2004-05-01

    We investigated whether prostaglandin ethanolamides (prostamides) E(2), F(2alpha), and D(2) exert some of their effects by 1) activating prostanoid receptors either per se or after conversion into the corresponding prostaglandins; 2) interacting with proteins for the inactivation of the endocannabinoid N-arachidonoylethanolamide (AEA), for example fatty acid amide hydrolase (FAAH), thereby enhancing AEA endogenous levels; or 3) activating the vanilloid receptor type-1 (TRPV1). Prostamides potently stimulated cat iris contraction with potency approaching that of the corresponding prostaglandins. However, prostamides D(2), E(2), and F(2alpha) exhibited no meaningful interaction with the cat recombinant FP receptor, nor with human recombinant DP, EP(1-4), FP, IP, and TP prostanoid receptors. Prostamide F(2alpha) was also very weak or inactive in a panel of bioassays specific for the various prostanoid receptors. None of the prostamides inhibited AEA enzymatic hydrolysis by FAAH in cell homogenates, or AEA cellular uptake in intact cells. Furthermore, less than 3% of the compounds were hydrolyzed to the corresponding prostaglandins when incubated for 4 h with homogenates of rat brain, lung, or liver, and cat iris or ciliary body. Very little temperature-dependent uptake of prostamides was observed after incubation with rat brain synaptosomes or RBL-2H3 cells. We suggest that prostamides' most prominent pharmacological actions are not due to transformation into prostaglandins, activation of prostanoid receptors, enhancement of AEA levels, or gating of TRPV1 receptors, but possibly to interaction with novel receptors that seem to be functional in the cat iris. PMID:14757851

  7. Prostaglandin E2 Regulates Liver versus Pancreas Cell Fate Decisions and Endodermal Outgrowth

    PubMed Central

    Nissim, Sahar; Sherwood, Richard I.; Wucherpfennig, Julia; Saunders, Diane; Harris, James M.; Esain, Virginie; Carroll, Kelli J.; Frechette, Gregory M.; Kim, Andrew J.; Hwang, Katie L.; Cutting, Claire C.; Elledge, Susanna; North, Trista E.; Goessling, Wolfram

    2014-01-01

    SUMMARY The liver and pancreas arise from common endodermal progenitors. How these distinct cell fates are specified is poorly understood. Here, we describe prostaglandin E2 (PGE2) as a regulator of endodermal fate specification during development. Modulating PGE2 activity has opposing effects on liver-versus-pancreas specification in zebrafish embryos as well as mouse endodermal progenitors. The PGE2 synthetic enzyme cox2a and receptor ep2a are patterned such that cells closest to PGE2 synthesis acquire a liver fate whereas more distant cells acquire a pancreas fate. PGE2 interacts with the bmp2b pathway to regulate fate specification. At later stages of development, PGE2 acting via the ep4a receptor promotes outgrowth of both the liver and pancreas. PGE2 remains important for adult organ growth, as it modulates liver regeneration. This work provides in vivo evidence that PGE2 may act as a morphogen to regulate cell fate decisions and outgrowth of the embryonic endodermal anlagen. PMID:24530296

  8. Intracrine prostaglandin E(2) signalling regulates hypoxia-inducible factor-1α expression through retinoic acid receptor-β.

    PubMed

    Fernández-Martínez, Ana B; Jiménez, María I Arenas; Manzano, Victoria Moreno; Lucio-Cazaña, Francisco J

    2012-12-01

    We have previously found in human renal proximal tubular HK-2 cells that hypoxia- and all-trans retinoic acid-induced hypoxia-inducible factor-1α up-regulation is accompanied by retinoic acid receptor-β up-regulation. Here we first investigated whether hypoxia-inducible factor-1α expression is dependent on retinoic acid receptor-β and our results confirmed it since (i) hypoxia-inducible factor-1α-inducing agents hypoxia, hypoxia-mimetic agent desferrioxamine, all-trans retinoic acid and interleukin-1β increased retinoic acid receptor-β expression, (ii) hypoxia-inducible factor-1α up-regulation was prevented by retinoic acid receptor-β antagonist LE-135 or siRNA retinoic acid receptor-β and (iii) there was direct binding of retinoic acid receptor-β to the retinoic acid response element in hypoxia-inducible factor-1α promoter upon treatment with all-trans retinoic acid and 16,16-dimethyl-prostaglandin E(2). Since intracellular prostaglandin E(2) mediates hypoxia-inducible factor-1α up-regulation in normoxia in HK-2 cells, we next investigated and confirmed, its role in the up-regulation of retinoic acid receptor-β in normoxia by hypoxia-inducible factor-1α-inducing agents all-trans retinoic acid, interleukin-1β and 16,16-dimethyl-prostaglandin E(2) by inhibiting cyclooxygenases, prostaglandin influx transporter or EP receptors. Interestingly, the hypoxia-induced increase in retinoic acid receptor-β expression and accumulation of hypoxia-inducible factor-1α was also blocked by the inhibitors tested. This is the first time, to our knowledge, that retinoic acid receptor-β signalling is involved in the control of the expression of transcription factor hypoxia-inducible factor-1α in both normoxia and hypoxia and that retinoic acid receptor-β expression is found to be strictly regulated by intracellular prostaglandin E(2). Given the relevance of hypoxia-inducible factor-1α in the kidney in terms of tumorigenesis, progressive renal failure, production

  9. Prostaglandin F2a activates stress response signaling and induces expression of activating transcription factor 3 (ATF3) in bovine large luteal cells

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The pulsatile uterine secretion of prostaglandin F2 alpha (PGF) triggers the regression of the corpus luteum (CL). Recent studies have explored global changes in gene expression in response to PGF that may contribute to structural and functional regression of the CL. Activating transcription facto...

  10. Prostaglandins regulate nuclear localization of Fascin and its function in nucleolar architecture

    PubMed Central

    Groen, Christopher M.; Jayo, Asier; Parsons, Maddy; Tootle, Tina L.

    2015-01-01

    Fascin, a highly conserved actin-bundling protein, localizes and functions at new cellular sites in both Drosophila and multiple mammalian cell types. During Drosophila follicle development, in addition to being cytoplasmic, Fascin is in the nuclei of the germline-derived nurse cells during stages 10B–12 (S10B–12) and at the nuclear periphery during stage 13 (S13). This localization is specific to Fascin, as other actin-binding proteins, Villin and Profilin, do not exhibit the same subcellular distribution. In addition, localization of fascin1 to the nucleus and nuclear periphery is observed in multiple mammalian cell types. Thus the regulation and function of Fascin at these new cellular locations is likely to be highly conserved. In Drosophila, loss of prostaglandin signaling causes a global reduction in nuclear Fascin and a failure to relocalize to the nuclear periphery. Alterations in nuclear Fascin levels result in defects in nucleolar morphology in both Drosophila follicles and cultured mammalian cells, suggesting that nuclear Fascin plays an important role in nucleolar architecture. Given the numerous roles of Fascin in development and disease, including cancer, our novel finding that Fascin has functions within the nucleus sheds new light on the potential roles of Fascin in these contexts. PMID:25808493

  11. Regulation of bovine oviductal NO synthesis by follicular steroids and prostaglandins.

    PubMed

    Kobayashi, Yoshihiko; Yamamoto, Yuki; Kageyama, Soichi; Hirayama, Hiroki; Kimura, Koji; Okuda, Kiyoshi

    2016-06-01

    Nitric oxide (NO) is a regulator of sperm motility, oocyte/embryo survival, and waves of contraction/relaxation in mammalian oviducts. As follicles control oviductal functions by two routes at least, (1) a systemic way via blood vessels before ovulation, (2) a direct way by entering of follicular fluid through fimbria at ovulation, we hypothesized that NO synthesis in the bovine oviduct is regulated by follicular steroids and prostaglandins (PGs). Quantification of mRNA expressions in the ampullary tissues showed that inducible NO synthase (NOS2) mRNA expression was highest on the day of ovulation (day 0). By contrast, NOS2 mRNA expression in the isthmus was highest on days 5-6 and lowest on days 19-21. Endothelial NOS (NOS3) mRNA expressions in either the ampulla or the isthmus did not change during the estrous cycle. PGE2 and PGF2α increased NOS2 mRNA expressions in cultured ampullary oviductal epithelial cells after 1-h incubation. These increases were suppressed by an antagonist of E-prostanoid receptor type 2, one of the PGE2 receptor. Estradiol-17β decreased the expression of NOS2 mRNA expression in cultured isthmic epithelial cells 24h after treatment. This effect was suppressed by an antagonist of estrogen receptorα(ESR1). Expression of ESR1 was highest on days 19-21 in the isthmic tissues. The overall findings indicate region-specific difference of NO synthesis in the oviduct. PGs flowed from ruptured follicle may up-regulate NO synthesis in the oviductal epithelium, whereas circulating E2 seems to inhibit NO synthesis via ESR1 in the isthmus at the follicular stage. PMID:26940101

  12. Prostaglandin E2 promotes neural proliferation and differentiation and regulates Wnt target gene expression.

    PubMed

    Wong, Christine T; Ussyshkin, Netta; Ahmad, Eizaaz; Rai-Bhogal, Ravneet; Li, Hongyan; Crawford, Dorota A

    2016-08-01

    Prostaglandin E2 (PGE2 ) is an endogenous lipid molecule that regulates important physiological functions, including calcium signaling, neuronal plasticity, and immune responses. Exogenous factors such as diet, exposure to immunological agents, toxic chemicals, and drugs can influence PGE2 levels in the developing brain and have been associated with autism disorders. This study seeks to determine whether changes in PGE2 level can alter the behavior of undifferentiated and differentiating neuroectodermal (NE-4C) stem cells and whether PGE2 signaling impinges on the Wnt/β-catenin pathways. We show that PGE2 increases proliferation of undifferentiated NE-4C stem cells. PGE2 also promotes the progression of NE-4C stem cell differentiation into neuronal-lineage cells, which is apparent by accelerated appearance of neuronal clusters (neurospheres) and earlier expression of the neuronal marker microtubule-associated protein tau. Furthermore, PGE2 alters the expression of downstream Wnt-regulated genes previously associated with neurodevelopmental disorders. In undifferentiated stem cells, PGE2 downregulates Ptgs2 expression and upregulates Mmp9 and Ccnd1 expression. In differentiating neuronal cells, PGE2 causes upregulation of Wnt3, Tcf4, and Ccnd1. The convergence of the PGE2 and the Wnt pathways is also apparent through increased expression of active β-catenin, a key signaling component of the Wnt/β-catenin pathways. This study provides novel evidence that PGE2 influences progression of neuronal development and influences Wnt target gene expression. We discuss how these findings could have potential implications for neurodevelopmental disorders such as autism. © 2016 Wiley Periodicals, Inc. PMID:27265882

  13. Conceptus-derived prostaglandins regulate gene expression in the endometrium prior to pregnancy recognition in ruminants

    PubMed Central

    Spencer, Thomas E.; Forde, Niamh; Dorniak, Piotr; Hansen, Thomas R.; Romero, Jared J.; Lonergan, Patrick

    2013-01-01

    In cattle, the blastocyst hatches from the zona pellucida on days 8 to 9 and then forms a conceptus that grows and elongates into an ovoid and then filamentous shape between days 9 and 16. The growing conceptus synthesizes and secretes prostaglandins and interferon tau. Our hypothesis was that the ovoid conceptus exerts a local effect on the endometrium prior to maternal recognition of pregnancy on day 16 in cattle. In Study One, synchronized cyclic heifers received nothing or 20 in vitro produced blastocysts on day 7, and uteri were collected on day 13. Interferon tau was not detected by radioimmunoassay in the uterine flush of pregnant heifers containing multiple ovoid conceptuses; however, total prostaglandin levels were higher in the uterine lumen of pregnant as compared to cyclic heifers. Microarray analysis revealed that 44 genes were increased in the endometrium of day 13 pregnant as compared to cyclic heifers, and many of those genes were classical Type I IFN-stimulated genes (ISGs). Studies Two and Three determined effects of infusing prostaglandins at the levels produced by the elongating day 14 conceptus into the uterine lumen of cyclic ewes on ISG expression in the endometrium. Results indicated that prostaglandin infusion increased the abundance of several ISGs in the endometrium. These studies support the hypothesis that the day 13 conceptus secretes prostaglandins that act locally in a paracrine manner to alter gene expression in the endometrium prior to pregnancy recognition in cattle. PMID:23966582

  14. Regulation of purinergic signaling by prostaglandin E2 in murine macrophages.

    PubMed

    Ito, Masaaki; Matsuoka, Isao

    2008-08-01

    Extracellular nucleotides are primary signals for tissue injury, acting together with various chemical mediators such as prostanoids at the inflammatory site. We investigated whether prostaglandin E2 (PGE2) affects purinergic signaling in murine J774 macrophages. J774 cells expressed four different purinoceptor mRNAs: the ionotropic P2X4 and P2X7 receptors and G-protein-coupled P2Y2 and P2Y6 receptors. Functional responses mediated by these purinoceptor subtypes were confirmed by measurement of intracellular Ca2+ concentration ([Ca2+]i) in fura-2-loaded cells. Thus, low concentrations (10 microM) of ATP (P2Y2 agonist) and UDP (P2Y6 agonist) evoked Ca2+ transient in a phospholipase C (PLC)-dependent manner, whereas the P2X7 agonist benzoylbenzoyl-ATP (BzATP, 500 microM) caused a sustained rise in [Ca2+]i. Furthermore, ivermectin, an activator of the P2X4-receptor channel, enhanced the ATP-induced [Ca2+]i elevation. PGE2 inhibited ATP- and UDP-induced [Ca2+]i elevation, without affecting the BzATP-induced sustained [Ca2+]i elevation. Stimulation of J774 cells by UDP or BzATP increased the production of macrophage inflammatory peptide-alpha (MIP-alpha). PGE2 abolished the UDP-induced MIP-alpha production, but not the BzATP-induced one. These results demonstrate that purinergic signalings in macrophages were regulated by PGE2 in a subtype-specific manner. The different inhibitory effects on distinct purinoceptor functions may be related to the anti-inflammatory property of PGE2. PMID:18678987

  15. Effects on body temperature of prostaglandins of the A, E and F series on injection into the third ventricle of unanaesthetized cats and rabbits.

    PubMed

    Milton, A S; Wendlandt, S

    1971-10-01

    1. Prostaglandins were injected into the third ventricle of unanaesthetized cats and rabbits whilst rectal temperature was recorded.2. In cats prostaglandin E(1) and E(2) (PGE(1) and PGE(2)) produced hyperthermia which mostly began within a minute of injection and lasted 1 or more hours. With PGE(1) the hyperthermia was shown to be dose dependent between 10 ng and 10 mug (2.8 x 10(-11) and 2.8 x 10(-8)M). The hyperthermia was associated with vigorous shivering, skin vasoconstriction and piloerection. In several experiments a secondary rise in temperature occurred a few hours after the injection but such an effect was sometimes observed with control injections of 0.9% NaCl solution as well.3. None of the other prostaglandins (A(1), F(1alpha), F(2alpha)) examined in cats had an immediate or strong effect on temperature comparable to the hyperthermia produced by PGE(1) and PGE(2).4. In rabbits PGE(1) (2 mug) also caused hyperthermia which began shortly after the injection and lasted for hours. PGF(2alpha) and PGA(1), did not affect temperature.5. In cats it was seen that an intraperitoneal injection of 4-acetamidophenol (paracetamol 50 mg/kg) did not affect the initial strong hyperthermia produced by PGE(1) and PGE(2) but abolished the secondary rise.6. The possibility is discussed that PGE(1) plays a role as a central transmitter or modulator in temperature regulation. PMID:4330929

  16. Influence of prostaglandins on contractility of the isolated human cervical muscle.

    PubMed

    Bryman, I; Sahni, S; Norström, A; Lindblom, B

    1984-03-01

    The contractile activity of smooth muscle from the pregnant and nonpregnant human cervix uteri was studied in organ bath experiments. Several patterns of spontaneous activity with varying frequency and amplitude were observed. Prostaglandin E2 inhibited muscle activity in a concentration-dependent manner, and total inhibition was achieved in pregnant tissue at extremely low concentrations. Prostaglandin F2 alpha, on the other hand, did not influence spontaneous contractions. Prostaglandin I2 and 6-keto-prostaglandin F1 alpha had an inhibitory effect but only at comparatively high concentrations. 5,8,11,14-Eicosatetraynoic acid and indomethacin abolished spontaneous contractions, indicating a regulatory influence of endogenous prostanoids on cervical contractility. The extreme sensitivity to prostaglandin E2 and enhancement of its action during early pregnancy provide evidence for a specific role of this compound in controlling cervical smooth muscle activity in the human female. PMID:6583598

  17. Prostaglandin E2 in tick saliva regulates macrophage cell migration and cytokine profile

    PubMed Central

    2013-01-01

    Background Ticks are obligate hematophagous ectoparasites that suppress the host’s immune and inflammatory responses by secreting immuno-modulatory and anti-inflammatory molecules in their saliva. In previous studies we have shown that tick salivary gland extract (SGE) and saliva from Dermacentor variabilis have distinct effects on platelet-derived growth factor (PDGF)-stimulated IC-21 macrophage and NIH3T3-L1 fibroblast migration. Since tick saliva contains a high concentration of prostaglandin E2 (PGE2), a potent modulator of inflammation, we used a PGE2 receptor antagonist to evaluate the role of PGE2 in the different migratory responses induced by saliva and its impact on macrophage cytokine profile. Methods Adult ticks were fed on female New Zealand white rabbits for 5-8 days. Female ticks were stimulated with dopamine/theophylline to induce salivation and saliva was pooled. Competitive enzyme immunoassays (EIA) were used to measure saliva PGE2 content and the changes in macrophage intracellular cyclic adenosine monophosphate (cAMP) levels. The effects of tick saliva on macrophage and fibroblast migration were assessed in the absence and presence of the PGE2 receptor antagonist, AH 6809, using blind well chamber assays. A cytokine antibody array was used to examine the effects of tick saliva on macrophage cytokine secretion. Statistical significance was determined by one-way ANOVA; Student Newman-Kuels post-test was used for multiple comparisons. Results The saliva-induced increase in PDGF-stimulated macrophage migration was reversed by AH 6809. The inhibition of PDGF-stimulated fibroblast migration by saliva was also antagonist-sensitive. Tick saliva induced macrophages to secrete copious amounts of PGE2, and conditioned medium from these cells caused an AH 6809-sensitive inhibition of stimulated fibroblast migration, showing that macrophages can regulate fibroblast activity. We show that tick saliva decreased the secretion of the pro

  18. Androgen regulation of thromboxane A2/prostaglandin H2 receptor expression in human erythroleukemia cells.

    PubMed

    Matsuda, K; Mathur, R S; Duzic, E; Halushka, P V

    1993-12-01

    Thromboxane A2 (TxA2), a platelet aggregator and vasoconstrictor, has been implicated as a potential mediator of cardiovascular diseases. Abuse of androgenic steroids has been associated with thrombotic cardiovascular diseases. Human erythroleukemia (HEL) cells, a megakaryocyte-like cell line, express functional TxA2/prostaglandin H2 (PGH2) receptors with characteristics similar to those seen in platelets. This study characterized testosterone regulation of HEL cell TxA2/PGH2 receptors. TxA2/PGH2 receptor affinity (Kd) and density (Bmax) were determined via equilibrium binding experiments using the radiolabeled TxA2 mimetic (1S-[1 alpha,2 beta(5Z),3 alpha(1E,3R*),4 alpha])-7-(3-[3-hydroxy-4-(4'- iodophenoxy)-1-butenyl]-7-oxabicyclo[2.2.1]heptan-2-yl)-5-he ptenoic acid (125I-labeled BOP). Testosterone (200 nM) but not estradiol increased Bmax from 108 +/- 9 fmol/mg protein to 157 +/- 9 fmol/mg protein (n = 7 experiments; P < 0.01) without any significant change in Kd. Testosterone had no significant effect on alpha 2-adrenergic receptor density. The maximum increase in intracellular free calcium induced by the TxA2 agonists I-BOP or U-46619 was significantly (P < 0.005) greater in testosterone-treated cells compared with controls. Hydroxyflutamide (1 microM), an androgen-receptor antagonist, completely blocked the effect of testosterone (P < 0.01). Dihydrotestosterone, the active metabolite of testosterone, also increased Bmax in a concentration-dependent manner and was more potent than testosterone. The effect of testosterone to increase Bmax was significantly (P < 0.01) inhibited by coincubation with cycloheximide (0.1 microgram/ml) or actinomycin D (10 ng/ml). These results indicate that androgenic steroids regulate the expression of functional TxA2/PGH2 receptors in HEL cells. These findings may have relevance to cardiovascular disease. PMID:8279549

  19. Clinical applications of prostaglandins in Obstetrics and Gynaecology.

    PubMed

    Karim, S M

    1982-10-01

    Although a number of potential practical uses of prostaglandins have been identified, these compounds have so far found clinical applications mainly in Obstetrics and Gynaecology. It is almost 15 years since a prostaglandin was first used for the induction of term labour and prostaglandin E2 is now commercially available for this purpose in many countries. For the termination of second trimester pregnancy, prostaglandins have almost completely replaced other methods previously in use. Other areas where prostaglandins are routinely used or where their uses are being developed, include menstrual induction, preevacuation dilatation of the cervix in the first trimester, termination of pregnancy in cases of missed abortion, intrauterine fetal death and other types of abnormal pregnancies, control of post-partum haemorrhage, treatment of post-partum or post surgical urine retention and ripening of the cervix prior to induction of labour at term. In early studies, prostaglandins E2 and F2 alpha were used for all the applications listed above. In order to increase efficacy and reduce side effects, a number of synthetic analogues were later evaluated for application in selected areas. Those with modification in the 15 and 16 positions of PGE2 and PGF2 alpha molecules have undergone extensive clinical trials and some of these analogues are now in routine use. The current status of the practical applications of prostaglandins in Obstetrics and Gynaecology is reviewed. PMID:6299163

  20. The Prostaglandin E2 Receptor EP4 Regulates Obesity-Related Inflammation and Insulin Sensitivity

    PubMed Central

    Yasui, Mika; Tamura, Yukinori; Minami, Manabu; Higuchi, Sei; Fujikawa, Risako; Ikedo, Taichi; Nagata, Manabu; Arai, Hidenori; Murayama, Toshinori; Yokode, Masayuki

    2015-01-01

    With increasing body weight, macrophages accumulate in adipose tissue. There, activated macrophages secrete numerous proinflammatory cytokines and chemokines, giving rise to chronic inflammation and insulin resistance. Prostaglandin E2 suppresses macrophage activation via EP4; however, the role of EP4 signaling in insulin resistance and type 2 diabetes mellitus remains unknown. In this study, we treated db/db mice with an EP4-selective agonist, ONO-AE1-329, for 4 weeks to explore the role of EP4 signaling in obesity-related inflammation in vivo. Administration of the EP4 agonist did not affect body weight gain or food intake; however, in the EP4 agonist–treated group, glucose tolerance and insulin resistance were significantly improved over that of the vehicle–treated group. Additionally, administration of the EP4 agonist inhibited the accumulation of F4/80-positive macrophages and the formation of crown-like structures in white adipose tissue, and the adipocytes were significantly smaller. The treatment of the EP4 agonist increased the number of anti-inflammatory M2 macrophages, and in the stromal vascular fraction of white adipose tissue, which includes macrophages, it markedly decreased the levels of proinflammatory cytokines and chemokines. Further, EP4 activation increased the expression of adiponectin and peroxidase proliferator–activated receptors in white adipose tissue. Next, we examined in vitro M1/M2 polarization assay to investigate the impact of EP4 signaling on determining the functional phenotypes of macrophages. Treatment with EP4 agonist enhanced M2 polarization in wild-type peritoneal macrophages, whereas EP4-deficient macrophages were less susceptible to M2 polarization. Notably, antagonizing peroxidase proliferator–activated receptor δ activity suppressed EP4 signaling-mediated shift toward M2 macrophage polarization. Thus, our results demonstrate that EP4 signaling plays a critical role in obesity-related adipose tissue inflammation

  1. Close teamwork between Nrf2 and peroxiredoxins 1 and 6 for the regulation of prostaglandin D2 and E2 production in macrophages in acute inflammation.

    PubMed

    Ishii, Tetsuro

    2015-11-01

    Inflammation is a complex biological self-defense reaction triggered by tissue damage or infection by pathogens. Acute inflammation is regulated by the time- and cell type-dependent production of cytokines and small signaling molecules including reactive oxygen species and prostaglandins. Recent studies have unveiled the important role of the transcription factor Nrf2 in the regulation of prostaglandin production through transcriptional regulation of peroxiredoxins 1 and 6 (Prx1 and Prx6) and lipocalin-type prostaglandin D synthase (L-PGDS). Prx1 and Prx6 are multifunctional proteins important for cell protection against oxidative stress, but also work together to facilitate production of prostaglandins E2 and D2 (PGE2 and PGD2). Prx1 secreted from cells under mild oxidative stress binds Toll-like receptor 4 and induces NF-κB activation, important for the expression of cyclooxygenase-2 and microsomal PGE synthase-1 (mPGES-1) expression. The activated MAPKs p38 and ERK phosphorylate Prx6, leading to NADPH oxidase-2 activation, which contributes to production of PGD2 by hematopoietic prostaglandin D synthase (H-PGDS). PGD2 and its end product 15-deoxy-∆(12,14)-prostaglandin J2 (15d-PGJ2) activate Nrf2 thereby forming a positive feedback loop for further production of PGD2 by L-PGDS. Maintenance of cellular glutathione levels is an important role of Nrf2 not only for cell protection but also for the synthesis of prostaglandins, as mPGES-1 and H-PGDS require glutathione for their activities. This review is aimed at describing the functions of Prx1 and Prx6 in the regulation of PGD2 and PGE2 production in acute inflammation in macrophages and the importance of 15d-PGJ2 as an intrinsic Nrf2 activator. PMID:25968070

  2. The effect of cloprostenol on human luteal steroid and prostaglandin secretion in vitro.

    PubMed Central

    McDougall, A N; Walker, F M; Watson, J

    1977-01-01

    1 Human luteal tissue slices from days 18, 21 and 25 of the menstrual cycle were superfused in vitro with Medium 199 alone or containing cloprostenol (1 microgram/ml). Concentrations of progesterone, oestradiol-17beta and prostaglandins F2alpha and E2 were determined in the superfusate samples. 2 Secretion of steroids and prostaglandins was maintained at an approximately constant level throughout the experiments (21 h in one case) when the tissue was perfused with M199 alone. 3 Superfusion with cloprostenol (1 microgram/ml) resulted in an initial depression of progesterone and oestradiol-17beta but this was not maintained, levels returning to control values or showing an increase, while superfusion with cloprostenol continued. Cloprostenol is not therefore considered to be luteolytic at this dose and under these conditions for human luteal tissue in vitro. 4 Superfusion with cloprostenol (1 microgram/ml) also resulted in a large stimulation of secretion of endogenous prostaglandin F2 alpha following a short lag phase. This stimulation was possibly due to the initial depression of progesterone secretion. A short-lived stimulation of prostaglandin E2 secretion was also observed. 5 The significance of the increase in prostaglandin E2 secretion and the interrelationships between the various changes observed with cloprostenol are difficult to interpret. PMID:890210

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

    PubMed Central

    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

  4. The Prostaglandin E2-EP3 Receptor Axis Regulates Anaplasma phagocytophilum-Mediated NLRC4 Inflammasome Activation.

    PubMed

    Wang, Xiaowei; Shaw, Dana K; Hammond, Holly L; Sutterwala, Fayyaz S; Rayamajhi, Manira; Shirey, Kari Ann; Perkins, Darren J; Bonventre, Joseph V; Velayutham, Thangam S; Evans, Sean M; Rodino, Kyle G; VieBrock, Lauren; Scanlon, Karen M; Carbonetti, Nicholas H; Carlyon, Jason A; Miao, Edward A; McBride, Jere W; Kotsyfakis, Michail; Pedra, Joao H F

    2016-08-01

    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-EP3 receptor during Salmonella infection when compared to A. phagocytophilum. Collectively, we reveal the existence of a functionally distinct NLRC4 inflammasome illustrated by the rickettsial agent A. phagocytophilum. PMID:27482714

  5. The Prostaglandin E2-EP3 Receptor Axis Regulates Anaplasma phagocytophilum-Mediated NLRC4 Inflammasome Activation

    PubMed Central

    Wang, Xiaowei; Shaw, Dana K.; Hammond, Holly L.; Sutterwala, Fayyaz S.; Rayamajhi, Manira; Shirey, Kari Ann; Perkins, Darren J.; Bonventre, Joseph V.; Velayutham, Thangam S.; Evans, Sean M.; Rodino, Kyle G.; VieBrock, Lauren; Scanlon, Karen M.; Carbonetti, Nicholas H.; Carlyon, Jason A.; Miao, Edward A.; McBride, Jere W.; Kotsyfakis, Michail

    2016-01-01

    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-EP3 receptor during Salmonella infection when compared to A. phagocytophilum. Collectively, we reveal the existence of a functionally distinct NLRC4 inflammasome illustrated by the rickettsial agent A. phagocytophilum. PMID:27482714

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

    SciTech Connect

    Sonnenburg, W.K.

    1987-01-01

    In the rabbit cortical collecting tubule (RCCT), prostaglandin E/sub 1/ (PGE/sub 1/) and prostaglandin E/sub 2/ (PGE/sub 2/) at 1 nM inhibit arginine-vasopressin (AVP)-induced water reabsorption, while 100 nM PGE/sub 1/ and PGE/sub 2/ alone stimulate water reabsorption. Reported here are studies designed to investigate the molecular basis for the biphasic physiological action of PGE/sub 1/ and PGE/sub 2/ in the collecting duct. In freshly isolated RCCT cells, PGE/sub 1/, PGE/sub 2/, and 16,16-dimethyl-PGE/sub 2/ (DM-PGE/sub 2/) stimulated cAMP synthesis at concentrations ranging from 0.1 to 10 M. Other prostaglandins including the synthetic PGE/sub 2/ analogue, sulprostone, failed to stimulate cAMP synthesis. Moreover, sulprostone did not antagonize PGE/sub 2/-stimulated cAMP formation. In contrast, PGE/sub 2/ and sulprostone at concentrations ranging from 1 to 100 nM, inhibited AVP-induced cAMP accumulation in freshly isolated RCCT cells. PGE/sub 2/, PGE/sub 1/, DM-PGE/sub 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/sub 2/ binding to freshly isolated RCCT cell membranes was characterized. Two different classes of PGE/sub 2/ binding were detected. //sup 3/H/PGE/sub 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, //sup 3/H/ PGE/sub 2/ binding to the low affinity class of sites was decreased by GTP S; this inhibitory effect was not blocked by pertussis toxin pretreatment.

  7. Aldo Keto Reductase 1B7 and Prostaglandin F2α Are Regulators of Adrenal Endocrine Functions

    PubMed Central

    Lambert-Langlais, Sarah; Volat, Fanny; Manin, Michèle; Coudoré, François; Val, Pierre; Sahut-Barnola, Isabelle; Ragazzon, Bruno; Louiset, Estelle; Delarue, Catherine; Lefebvre, Hervé; Urade, Yoshihiro; Martinez, Antoine

    2009-01-01

    Prostaglandin F2α (PGF2α), represses ovarian steroidogenesis and initiates parturition in mammals but its impact on adrenal gland is unknown. Prostaglandins biosynthesis depends on the sequential action of upstream cyclooxygenases (COX) and terminal synthases but no PGF2α synthases (PGFS) were functionally identified in mammalian cells. In vitro, the most efficient mammalian PGFS belong to aldo-keto reductase 1B (AKR1B) family. The adrenal gland is a major site of AKR1B expression in both human (AKR1B1) and mouse (AKR1B3, AKR1B7). Thus, we examined the PGF2α biosynthetic pathway and its functional impact on both cortical and medullary zones. Both compartments produced PGF2α but expressed different biosynthetic isozymes. In chromaffin cells, PGF2α secretion appeared constitutive and correlated to continuous expression of COX1 and AKR1B3. In steroidogenic cells, PGF2α secretion was stimulated by adrenocorticotropic hormone (ACTH) and correlated to ACTH-responsiveness of both COX2 and AKR1B7/B1. The pivotal role of AKR1B7 in ACTH-induced PGF2α release and functional coupling with COX2 was demonstrated using over- and down-expression in cell lines. PGF2α receptor was only detected in chromaffin cells, making medulla the primary target of PGF2α action. By comparing PGF2α-responsiveness of isolated cells and whole adrenal cultures, we demonstrated that PGF2α repressed glucocorticoid secretion by an indirect mechanism involving a decrease in catecholamine release which in turn decreased adrenal steroidogenesis. PGF2α may be regarded as a negative autocrine/paracrine regulator within a novel intra-adrenal feedback loop. The coordinated cell-specific regulation of COX2 and AKR1B7 ensures the generation of this stress-induced corticostatic signal. PMID:19809495

  8. The prostaglandin D2 receptor CRTH2 regulates accumulation of group 2 innate lymphoid cells in the inflamed lung

    PubMed Central

    Tait Wojno, ED; Monticelli, LA; Tran, SV; Alenghat, T; Osborne, LC; Thome, JJ; Willis, C; Budelsky, A; Farber, DL; Artis, D

    2015-01-01

    Group 2 innate lymphoid cells (ILC2s) promote type 2 cytokine-dependent immunity, inflammation and tissue repair. While epithelial cell-derived cytokines regulate ILC2 effector functions, the pathways that control the in vivo migration of ILC2s into inflamed tissues remain poorly understood. Here, we provide the first demonstration that expression of the prostaglandin D2 (PGD2) receptor CRTH2 (chemoattractant receptor homologous molecule expressed on Th2 cells) regulates the in vivo accumulation of ILC2s in the lung. While a significant proportion of ILC2s isolated from healthy human peripheral blood expressed CRTH2, a smaller proportion of ILC2s isolated from non-diseased human lung expressed CRTH2, suggesting that dynamic regulation of CRTH2 expression might be associated with the migration of ILC2s into tissues. Consistent with this, murine ILC2s expressed CRTH2, migrated towards PGD2 in vitro and accumulated in the lung in response to PGD2 in vivo. Further, mice deficient in CRTH2 exhibited reduced ILC2 responses and inflammation in a murine model of helminth-induced pulmonary type 2 inflammation. Critically, adoptive transfer of CRTH2-sufficient ILC2s restored pulmonary inflammation in CRTH2-deficient mice. Together, these data identify a role for the PGD2-CRTH2 pathway in regulating the in vivo accumulation of ILC2s and the development of type 2 inflammation in the lung. PMID:25850654

  9. Oestradiol and prostaglandin F2α regulate sexual displays in females of a sex-role reversed fish

    PubMed Central

    Gonçalves, David; Costa, Silvia Santos; Teles, Magda C.; Silva, Helena; Inglês, Mafalda; Oliveira, Rui F.

    2014-01-01

    The mechanisms regulating sexual behaviours in female vertebrates are still poorly understood, mainly because in most species sexual displays in females are more subtle and less frequent than displays in males. In a sex-role reversed population of a teleost fish, the peacock blenny Salaria pavo, an external fertilizer, females are the courting sex and their sexual displays are conspicuous and unambiguous. We took advantage of this to investigate the role of ovarian-synthesized hormones in the induction of sexual displays in females. In particular, the effects of the sex steroids oestradiol (E2) and testosterone (T) and of the prostaglandin F2α (PGF2α) were tested. Females were ovariectomized and their sexual behaviour tested 7 days (sex steroids and PGF2α) and 14 days (sex steroids) after ovariectomy by presenting females to an established nesting male. Ovariectomy reduced the expression of sexual behaviours, although a significant proportion of females still courted the male 14 days after the ovary removal. Administration of PGF2α to ovariectomized females recovered the frequency of approaches to the male's nest and of courtship displays towards the nesting male. However, E2 also had a positive effect on sexual behaviour, particularly on the frequency of approaches to the male's nest. T administration failed to recover sexual behaviours in ovariectomized females. These results suggest that the increase in E2 levels postulated to occur during the breeding season facilitates female mate-searching and assessment behaviours, whereas PGF2α acts as a short-latency endogenous signal informing the brain that oocytes are mature and ready to be spawned. In the light of these results, the classical view for female fishes, that sex steroids maintain sexual behaviour in internal fertilizers and that prostaglandins activate spawning behaviours in external fertilizers, needs to be reviewed. PMID:24452030

  10. Evidence against a physiological role of prostaglandins in the regulation of noradrenaline release in the cat spleen.

    PubMed Central

    Dubocovich, M L; Langer, S Z

    1975-01-01

    1. The effects of prostaglandins E2 (PGE2) and indomethacin on responses and on noradrenaline overflow elicited by nerve stimulation were studied in the perfused cat's spleen, at different calcium concentrations in the perfusion medium: 0-26, 0-65 and 2-6 mve stimulation and in the overflow of the transmitter. PGE2 was more effective in reducing transmitter overflow at 5 than at 30 Hz. 3. Indomethacin, 14-0 muM, prevented the release of PGE-like material in the venous effluent of the spleen elicited by either nerve stimulation or by exogenous noradrenaline. 4. During exposure to 14-0 muM indomethacin there was no increase in responses to nerve stimulation or in the overflow of noradrenaline elicited by nerve stimulation at 5 or at 30 Hz. 5. Similar results to those obtained with exogenous PGE2 and with indomethacin in the presence of 2-6 mM calcium, were observed when the experiments were carried out in the presence of either 0-65 or 0-26 mM calcium. 6. In the presence of the alpha-adrenoceptor blocking agents, phenoxybenzamine (2-9 muM) or phentolamine (3-1 muM), the increase in transmitter overflow obtained during stimulation was 6-5 and 8-3-fold respectively. 7. Since inhibition of the synthesis of PGE did not increase transmitter overflow during nerve stimulation, it appears that the proposed negative feed-back mechanism mediated by endogenous prostaglandins does not play an important physiological role in the regulation of adrenergic neurotransmission in the cat spleen. In this tissue the major endogenous negative feed-back regulatory mechanism is triggered by the neurotransmitter through the activation of prejunctional alpha-adrenoceptors. PMID:171381

  11. Regulation of prostaglandin E{sub 2} synthesis after brain irradiation

    SciTech Connect

    Moore, Amy H.; Olschowka, John A.; Williams, Jacqueline P.; Okunieff, Paul; O'Banion, M. Kerry . E-mail: kerry_obanion@urmc.rochester.edu

    2005-05-01

    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{sub 2} (PGE{sub 2}) levels seen after radiation treatment. Methods and materials: To begin to determine the contributions of other enzymes involved in PGE{sub 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{sub 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{sub 2} levels by about 60%. Surprisingly, COX-1 inhibition with SC560 completely prevented the elevation of PGE{sub 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{sub 2} production in irradiated brain and reveal dependence of PGES isoforms expression on specific cyclooxygenase activities.

  12. Novel Roles for Hypoxia and Prostaglandin E2 in the Regulation of IL-8 During Endometrial Repair

    PubMed Central

    Maybin, Jacqueline A.; Hirani, Nikhil; Jabbour, Henry N.; Critchley, Hilary O.D.

    2011-01-01

    The endometrium has a remarkable capacity for efficient repair; however, factors involved remain undefined. Premenstrual progesterone withdrawal leads to increased prostaglandin (PG) production and local hypoxia. Here we determined human endometrial expression of interleukin-8 (IL-8) and the roles of PGE2 and hypoxia in its regulation. Endometrial biopsy specimens (n = 51) were collected. Endometrial cells and explants were exposed to 100 nmol/L of PGE2 or 0.5% O2. The endometrial IL-8 concentration peaked during menstruation (P < 0.001) and had a significant proangiogenic effect. IL-8 was increased by PGE2 and hypoxia in secretory but not proliferative explants, which suggests that exposure to progesterone is essential. In vitro progesterone withdrawal induced significant IL-8 up-regulation in proliferative explants primed with progestins, but only in the presence of hypoxia. Epithelial cells treated simultaneously with PGE2 and hypoxia demonstrated synergistic increases in IL-8. Inhibition of HIF-1 by short hairpin RNA abolished hypoxic IL-8 induction, and inhibition of NF-κB by an adenoviral dominant negative inhibitor decreased PGE2-induced IL-8 expression (P > 0.05). Increased menstrual IL-8 is consistent with a role in repair. Progesterone withdrawal, hypoxia, and PGE2 regulate endometrial IL-8 by acting via HIF-1 and NF-κB. Hence, progesterone withdrawal may activate two distinct pathways to initiate endometrial repair. PMID:21356375

  13. Regulation of prostaglandin production by nitric oxide; an in vivo analysis.

    PubMed Central

    Salvemini, D; Settle, S L; Masferrer, J L; Seibert, K; Currie, M G; Needleman, P

    1995-01-01

    1. Endotoxin E. Coli lipopolysaccharide (LPS)-treatment in conscious, restrained rats increased plasma and urinary prostaglandin (PG) and nitric oxide (NO) production. Inducible cyclo-oxygenase (COX-2) and nitric oxide synthase (iNOS) expression accounted for the LPS-induced PG and NO release since the glucocorticoid, dexamethasone inhibited both effects. Thus, LPS (4 mg kg-1) increased the plasma levels of nitrite/nitrate from 14 +/- 1 to 84 +/- 7 microM within 3 h and this rise was inhibited to 35 +/- 1 microM by dexamethasone. Levels of 6-keto PGF1 alpha in the plasma were below the detection limit of the assay (< 0.2 ng ml-1). However, 3 h after the injection of LPS these levels rose to 2.6 +/- 0.2 ng ml-1 and to 0.7 +/- 0.01 ng ml-1 after LPS in rats that received dexamethasone. 2. The induced enzymes were inhibited in vivo with selective COX and NOS inhibitors. Furthermore, NOS inhibitors, that did not affect COX activity in vitro markedly suppressed PG production in the LPS-treated animals. For instance, the LPS-induced increased in plasma nitrite/nitrate and 6-keto PGF1 alpha at 3 h was decreased to 18 +/- 2 microM and 0.5 +/- 0.02 ng ml-1, 23 +/- 1 microM and 0.7 +/- 0.01 ng ml-1, 29 +/- 2 microM and 1 +/- 0.01 ng ml-1 in rats treated with LPS in the presence of the NOS inhibitors NG-monomethyl-L-arginine, NG-nitro arginine methyl ester and aminoguanidine, respectively.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7542531

  14. Regulation of sulfated glycosaminoglycan production by prostaglandin E2 in cultured lung fibroblasts

    SciTech Connect

    Karlinsky, J.B.; Goldstein, R.H. )

    1989-08-01

    Prostaglandin E2 (PGE2) has been shown to increase the synthesis of hyaluronic acid in cultured fibroblasts by increasing the activity of hyaluronate synthetase, a group of plasma membrane-bound synthetic enzymes. We examined whether PGE2 also increased the activity of those enzyme systems involved in the synthesis of sulfated glycosaminoglycan in the human embryonic lung fibroblast. Exposure of cells to PGE2 resulted in dose-dependent increases in glucosamine incorporation into all sulfated glycosaminoglycan subtypes. PGE2 at 10(-7) mol/L increased total glycosaminoglycan per dish to 21.6 +/- 3.1 micrograms versus 12.0 +/- 2.5 micrograms in control untreated cultures. Stimulation of endogenous PGE2 production by bradykinin had a similar effect on glycosaminoglycan synthesis. To examine whether PGE2 affected sulfated glycosaminoglycan protein core production, cells were labeled with tritiated glucosamine in the presence of cycloheximide. Under these conditions, incorporation of radiolabel into all glycosaminoglycan subtypes was reduced. However, when exogenous sulfated glycosaminoglycan chain initiator (p-nitrophenyl beta-D-xyloside) was added, incorporation of tritiated glucosamine into sulfated glycosaminoglycan increased but not to levels found in control cultures. Application of PGE2 to cultures treated with cycloheximide alone, or to cultures treated with cycloheximide plus xyloside, increased tritiated glucosamine incorporation into chondroitin, dermatan sulfate, and to a lesser extent into heparan sulfate. We conclude that PGE2 stimulates synthesis of all sulfated glycosaminoglycan even in the absence of new protein core production, probably by increasing activities of sulfated glycosaminoglycan synthetase enzymes. PGE2 stimulation of heparan sulfate synthesis is partially dependent on the availability of heparan sulfate-specific protein core.

  15. Prostaglandin E2 regulates angiogenesis via activation of fibroblast growth factor receptor-1.

    PubMed

    Finetti, Federica; Solito, Raffaella; Morbidelli, Lucia; Giachetti, Antonio; Ziche, Marina; Donnini, Sandra

    2008-01-25

    Prostaglandin E(2) (PGE(2)) behaves as a mitogen in epithelial tumor cells as well as in many other cell types. We investigated the actions of PGE(2) on microvascular endothelial cells (capillary venular endothelial cells) with the purpose of delineating the signaling pathway leading to the acquisition of the angiogenic phenotype and to new vessel formation. PGE(2) (100 nM) produced activation of the fibroblast growth factor receptor 1 (FGFR-1), as measured by its phosphorylation, but not of vascular endothelial growth factor receptor 2. PGE(2) stimulated the EP3 subtype receptor, as deduced by abrogation of EP3 Galpha(i) subunit activity through pertussis toxin. Consistent with this result, in human umbilical venular endothelial cells missing the EP3 receptor, PGE(2) did not phosphorylate FGFR-1. Upon binding to its receptor, PGE(2) initiated an autocrine/paracrine signaling cascade involving the intracellular activation of c-Src, activation of matrix metalloproteinase (predominantly MMP2), which in turn caused the mobilization of membrane-anchored fibroblast growth factor-2 (FGF-2). In fact, in cells unable to release FGF-2 the transfection with both FGFR-1 and EP3 did not result in FGFR-1 phosphorylation in response to PGE(2). Relevance for the FGF2-FGFR-1 system was highlighted by confocal analysis, showing receptor internalization after cell exposure to the prostanoid. ERK1/2 appeared to be the distal signal involved, its phosphorylation being sensitive to either cSrc inhibitor or FGFR-1 blocker. Finally, PGE(2) stimulated cell migration and capillary formation in aortic rings, which were severely reduced by inhibitors of signaling molecules or by receptor antagonist. In conclusion, this study provides evidence for the involvement of FGFR-1 through FGF2 in eliciting PGE(2) angiogenic responses. This signaling pattern is similar to the autocrine-paracrine mechanism which operates in endothelial cells to support neovascular growth. PMID:18042549

  16. Prostaglandin E2 mediates growth arrest in NFS-60 cells by down-regulating interleukin-6 receptor expression.

    PubMed Central

    de Silva, Kumudika I; Daud, Asif N; Deng, JiangPing; Jones, Stephen B; Gamelli, Richard L; Shankar, Ravi

    2003-01-01

    Interleukin-6 (IL-6), a potent myeloid mitogen, and the immunosuppressive prostanoid prostaglandin E2 (PGE2) are elevated following thermal injury and sepsis. We have previously demonstrated that bone marrow myeloid commitment shifts toward monocytopoiesis and away from granulocytopoiesis during thermal injury and sepsis and that PGE2 plays a central role in this alteration. Here we investigated whether PGE2 can modulate IL-6-stimulated growth in the promyelocytic cell line, NFS-60, by down-regulating IL-6 receptor (IL-6r) expression. Exposure of NFS-60 cells to PGE2 suppressed IL-6-stimulated proliferation as well as IL-6r expression. Receptor down-regulation is functionally significant since IL-6-induced signal transduction through activators of transcription (STAT)-3 is also decreased. Down-regulation of IL-6r correlated with the ability of PGE2 to arrest cells in the G0/G1 phase of the cell cycle. PGE2 appears to signal through EP2 receptors. Butaprost (EP2 agonist) but not sulprostone (EP3 agonist) inhibited IL-6-stimulated proliferation. In addition, an EP2 antagonist (AH6809) alleviated the anti-proliferative effects of PGE2. NFS-60 cells express predominantly EP2 and EP4 receptors. While PGE2 down-regulated both the IL-6r protein and mRNA expression, it had no influence on EP2 or EP4 mRNA expression. The present study demonstrates that PGE2 is a potent down-regulator of IL-6r expression and thus may provide a mechanistic explanation for the granulocytopenia seen in thermal injury and sepsis. PMID:12429018

  17. A New Role for Lipocalin Prostaglandin D Synthase in the Regulation of Brown Adipose Tissue Substrate Utilization

    PubMed Central

    Virtue, Sam; Feldmann, Helena; Christian, Mark; Tan, Chong Yew; Masoodi, Mojgan; Dale, Martin; Lelliott, Chris; Burling, Keith; Campbell, Mark; Eguchi, Naomi; Voshol, Peter; Sethi, Jaswinder K.; Parker, Malcolm; Urade, Yoshihiro; Griffin, Julian L.; Cannon, Barbara; Vidal-Puig, Antonio

    2012-01-01

    In this study, we define a new role for lipocalin prostaglandin D synthase (L-PGDS) in the control of metabolic fuel utilization by brown adipose tissue (BAT). We demonstrate that L-PGDS expression in BAT is positively correlated with BAT activity, upregulated by peroxisome proliferator–activated receptor γ coactivator 1α or 1β and repressed by receptor-interacting protein 140. Under cold-acclimated conditions, mice lacking L-PGDS had elevated reliance on carbohydrate to provide fuel for thermogenesis and had increased expression of genes regulating glycolysis and de novo lipogenesis in BAT. These transcriptional differences were associated with increased lipid content in BAT and a BAT lipid composition enriched with de novo synthesized lipids. Consistent with the concept that lack of L-PGDS increases glucose utilization, mice lacking L-PGDS had improved glucose tolerance after high-fat feeding. The improved glucose tolerance appeared to be independent of changes in insulin sensitivity, as insulin levels during the glucose tolerance test and insulin, leptin, and adiponectin levels were unchanged. Moreover, L-PGDS knockout mice exhibited increased expression of genes involved in thermogenesis and increased norepinephrine-stimulated glucose uptake to BAT, suggesting that sympathetically mediated changes in glucose uptake may have improved glucose tolerance. Taken together, these results suggest that L-PGDS plays an important role in the regulation of glucose utilization in vivo. PMID:22923471

  18. Stimulation of prolactin synthesis and of adenosine 3':5'-cyclic phosphate formation by prostaglandins and thyroliberin in cultured rat pituitary cells.

    PubMed Central

    Gautvik, K M; Kriz, M

    1976-01-01

    1. The effects of prostaglandins E2 and F2alpha on prolactin synthesis were examined in a clonal strain of rat pituitary tumour cells, and compared with those of thyroliberin. 2. The prostaglandins and thyroliberin gave a dose-related and time-dependent stimulation of prolactin synthesis. The maximal effects (about twofold increases) were observed after 54h of treatment with 25nM-prostaglandin E2 and 2.5nM-prostaglandin F2alpha. A similar stimulation of prolactin synthesis was observed after 250nM-thyroliberin. The combined treatment with prostaglandins and thyroliberin did not increase prolactin synthesis over and above that obtained with each compound alone. 3. After removal of prostaglandins E2 and F2alpha there was a complete reversal of prolactin synthesis to pre-stimulation values 18h later (t1/2less than or equal to 9h). The rapid reversible effect of prostaglandins was in contrast with that of thyroliberin, where prolactin synthesis returned to control values with a t1/2 of about 42 h. 4. Prostaglandin E2 (5mum) and thyroliberin (5mum) increased cellular concentrations of cyclic AMP eight- and four-fold respectively. Maximal effects were observed after 2-5min of incubation. The increases in cyclic AMP were biphasic; normal values were obtained 60 min after the start of incubation with prostaglandin E2 or thyroliberin. 5. The dose/response curve showed that prostaglandin E2 caused maximal increase of cyclic AMP at 50nM. Concentrations of prostagland in E2 that caused half-maximal stimulation of cyclic AMP accumulation and of prolactin synthesis were 4 and 5nM respectively. 6. Combined treatment with prostaglandin E2 and thyroliberin in concentrations that separately caused maximal cyclic AMP increases did not result in a further increase in this cyclic nucleotide. 7. These results are consistent with a role of cyclic AMP in mediating the effects or prostaglandins and thyroliberin on prolactin synthesis. However, if cyclic AMP is involved as a common

  19. Prostaglandins: pharmacology and clinical application.

    PubMed

    Karim, S M; Hillier, K

    1974-01-01

    Prostaglandin research has been 1 of the most stimulating features of biomedical investigation in the past decade. Interest developed at a time of expanding knowledge of hormonal and neurohormonal behavior and research work received a tremendous impetus in the early 1960s with the elucidation in Sweden of the chemical structures of prostaglandins, followed by the discovery of their biosynthetic pathways. The original findings of large amounts of prostaglandin in the male accessory genital glands and their secretions, and subsequent discovery in the menstrual and amniotic fluids linked these substances with human production. As a result of further investigation, clinical applications of prostaglandins for the induction of labor and termination of early unwanted pregnancies have been developed. Apart from the functions of the prostaglandins in the reproductive area, they have been shown to have a widespread distribution in the body and produce many different pharmacological effects. Prostaglandins are thought to be involved in the regulation of blood pressure and through their vascular effects have therapeutic potential in the treatment of hypertension and peripheral vascular disease. Through their bronchodilator effect, some prostaglandins may become useful in the treatment of asthma. PMID:4611742

  20. Prostaglandin E2 Receptor Subtype 2 Regulation of Scavenger Receptor CD36 Modulates Microglial Aβ42 Phagocytosis

    PubMed Central

    Li, Xianwu; Melief, Erica; Postupna, Nadia; Montine, Kathleen S.; Keene, C. Dirk; Montine, Thomas J.

    2016-01-01

    Recent studies underline the potential relevance of microglial innate immune activation in Alzheimer disease. Primary mouse microglia that lack prostaglandin E2 receptor subtype 2 (EP2) show decreased innate immune-mediated neurotoxicity and increased amyloid β (Aβ) peptide phagocytosis, features that were replicated in vivo. Here, we tested the hypothesis that scavenger receptor CD36 is an effector of EP2-regulated Aβ phagocytosis. CD36 expression was 143-fold greater in mouse primary microglia than in primary astrocytes. Three different means of suppressing EP2 signaling increased and an agonist of EP2 decreased CD36 expression in primary wild-type microglia. Activation of Toll-like receptor (TLR) 3, TLR4, and TLR7, but not TLR2 or TLR9, reduced primary microglial CD36 transcription and cell surface CD36 protein and reduced Aβ42 phagocytosis as well. At each step, the effects of innate immune activation on CD36 were reversed by at least 50% by an EP2 antagonist, and this partial rescue of microglia Aβ42 phagocytosis was largely mediated by CD36 activity. Finally, we showed in hippocampus of wild-type mice that innate immune activation suppressed CD36 expression by an EP2-dependent mechanism. Taken together with results of others that found brain clearance of Aβ peptides and behavioral improvements mediated by CD36 in mice, regulation of CD36-mediated Aβ phagocytosis by suppression of EP2 signaling may provide a new approach to suppressing some aspects of Alzheimer disease pathogenesis. PMID:25452117

  1. The Regulation of Vascular Endothelial Growth Factor by Hypoxia and Prostaglandin F2α during Human Endometrial Repair

    PubMed Central

    Maybin, Jacqueline A.; Hirani, Nikhil; Brown, Pamela; Jabbour, Henry N.

    2011-01-01

    Context: The human endometrium has an exceptional capacity for repeated repair after menses, but its regulation remains undefined. Premenstrually, progesterone levels fall and prostaglandin (PG) F2α synthesis increases, causing spiral arteriole constriction. We hypothesized that progesterone withdrawal, PGF2α, and hypoxia increase vascular endothelial growth factor (VEGF), an endometrial repair factor. Design and Results: Endometrial biopsies were collected (n = 47) with ethical approval and consent. VEGF mRNA, quantified by quantitative RT-PCR, was increased during menstruation (P < 0.01).VEGF protein was maximally secreted from proliferative endometrial explants. Treatment of an endometrial epithelial cell line and primary human endometrial stromal cells with 100 nm PGF2α or hypoxia (0.5% O2) resulted in significant increases in VEGF mRNA and protein. VEGF was maximal when cells were cotreated with PGF2α and hypoxia simultaneously (P < 0.05–0.001). Secretory-phase endometrial explants also showed an increase in VEGF with cotreatment (P < 0.05). However, proliferative-phase explants showed no increase in VEGF on treatment with PGF2α and/or hypoxia. Proliferative tissue was induced to increase VEGF mRNA expression when exposed to progesterone and its withdrawal in vitro but only in the presence of hypoxia and PG. Hypoxia-inducible factor-1α (HIF-1α) silencing with RNA interference suppressed hypoxia-induced VEGF expression in endometrial cells but did not alter PGF2α-induced VEGF expression. Conclusions: Endometrial VEGF is increased at the time of endometrial repair. Progesterone withdrawal, PGF2α, and hypoxia are necessary for this perimenstrual VEGF expression. Hypoxia acts via HIF-1α to increase VEGF, whereas PGF2α acts in a HIF-1α-independent manner. Hence, two pathways regulate the expression of VEGF during endometrial repair. PMID:21677035

  2. Prostaglandin E2 Via Steroidogenic Factor-1 Coordinately Regulates Transcription of Steroidogenic Genes Necessary for Estrogen Synthesis in Endometriosis

    PubMed Central

    Attar, Erkut; Tokunaga, Hideki; Imir, Gonca; Yilmaz, M. Bertan; Redwine, David; Putman, Michael; Gurates, Bilgin; Attar, Rukset; Yaegashi, Nobuo; Hales, Dale B.; Bulun, Serdar E.

    2009-01-01

    Context: Products of at least five specific steroidogenic genes, including steroidogenic acute regulatory protein (StAR), which facilitates the entry of cytosolic cholesterol into the mitochondrion, side chain cleavage P450 enzyme, 3β-hydroxysteroid-dehydrogenase-2, 17-hydroxylase/17-20-lyase, and aromatase, which catalyzes the final step, are necessary for the conversion of cholesterol to estrogen. Expression and biological activity of StAR and aromatase were previously demonstrated in endometriosis but not in normal endometrium. Prostaglandin E2 (PGE2) induces aromatase expression via the transcriptional factor steroidogenic factor-1 (SF1) in endometriosis, which is opposed by chicken-ovalbumin upstream-transcription factor (COUP-TF) and Wilms’ tumor-1 (WT1) in endometrium. Objective: The aim of the study was to demonstrate a complete steroidogenic pathway leading to estrogen biosynthesis in endometriotic cells and the transcriptional mechanisms that regulate basal and PGE2-stimulated estrogen production in endometriotic cells and endometrium. Results: Compared with normal endometrial tissues, mRNA levels of StAR, side chain cleavage P450, 3β-hydroxysteroid-dehydrogenase-2, 17-hydroxylase/17-20-lyase, aromatase, and SF1 were significantly higher in endometriotic tissues. PGE2 induced the expression of all steroidogenic genes; production of progesterone, estrone, and estradiol; and StAR promoter activity in endometriotic cells. Overexpression of SF1 induced, whereas COUP-TFII or WT1 suppressed, StAR promoter activity. PGE2 induced coordinate binding of SF1 to StAR and aromatase promoters but decreased COUP-TFII binding in endometriotic cells. COUP-TFII or WT1 binding to both promoters was significantly higher in endometrial compared with endometriotic cells. Conclusion: Endometriotic cells contain the full complement of steroidogenic genes for de novo synthesis of estradiol from cholesterol, which is stimulated by PGE2 via enhanced binding of SF1 to promoters

  3. Prostaglandins attenuate cardiac contractile dysfunction produced by free radical generation but not by hydrogen peroxide.

    PubMed

    Zimmer, K M; Karmazyn, M

    1997-11-01

    The aim of this study was to examine and compare the potential influence of cyclooxygenase or lipoxygenase derived metabolites of arachidonic acid on myocardial injury produced either by a free radical generating system consisting of purine plus xanthine oxidase or that produced by hydrogen peroxide. A free radical generating system consisting of purine (2.3 mM) and xanthine oxidase (10 U/L) as well as hydrogen peroxide (75 microM) produced significant functional changes in the absence of either significant deficits in high energy phosphates or ultrastructural damage. Prostaglandin F2 alpha (30 nM) significantly attenuated both the negative inotropic effect of purine plus xanthine oxidase as well as the ability of the free radical generator to elevate diastolic pressure. An identical concentration of prostaglandin 12 (prostacyclin) significantly reduced diastolic pressure elevation only and had no effect on contractile depression. The salutary effects of the two PGs occurred in the absence of any inhibitory influence on superoxide anion generation produced by the purine and xanthine oxidase reaction. None of prostaglandins modulated the response to hydrogen peroxide. In addition, neither prostaglandin E2 nor leukotrienes exerted any effect on changes produced by either type of oxidative stress. A 5 fold elevation in the concentrations of free radical generators or hydrogen peroxide produced extensive injury as characterized by a virtual total loss in contractility, 400% elevation in diastolic pressure, ultrastructural damage and significant depletions in high energy phosphate content. None of these effects were modulated by eicosanoid treatment. Our results therefore demonstrate a selective ability of both prostaglandin F2 alpha and to a lesser extent prostacyclin, to attenuate dysfunction produced by purine plus xanthine oxidase but not hydrogen peroxide. It is possible that these eicosanoids may represent endogenous protective factors under conditions of enhanced

  4. Lung Myofibroblasts Are Characterized by Down-Regulated Cyclooxygenase-2 and Its Main Metabolite, Prostaglandin E2

    PubMed Central

    Gabasa, Marta; Royo, Dolores; Molina-Molina, Maria; Roca-Ferrer, Jordi; Pujols, Laura; Picado, Cesar

    2013-01-01

    Background Prostaglandin E2 (PGE2), the main metabolite of cyclooxygenase (COX), is a well-known anti-fibrotic agent. Moreover, myofibroblasts expressing α-smooth muscle actin (α-SMA), fibroblast expansion and epithelial-mesenchymal transition (EMT) are critical to the pathogenesis of idiopathic pulmonary fibrosis (IPF). Our aim was to investigate the expression of COX-2 and PGE2 in human lung myofibroblasts and establish whether fibroblast-myofibroblast transition (FMT) and EMT are associated with COX-2 and PGE2 down-regulation. Methods Fibroblasts obtained from IPF patients (n = 6) and patients undergoing spontaneous pneumothorax (control, n = 6) and alveolar epithelial cell line A549 were incubated with TGF-β1 and FMT and EMT markers were evaluated. COX-2 and α-SMA expression, PGE2 secretion and cell proliferation were measured after IL-1β and PGE2 incubation. Results Myofibroblasts from both control and IPF fibroblast cultures stimulated with IL-1β showed no COX-2 expression. IPF fibroblasts showed increased myofibroblast population and reduced COX-2 expression in response to IL-1β. TGF-β1 increased the number of myofibroblasts in a time-dependent manner. In contrast, TGF-β1 induced slight COX-2 expression at 4 h (without increase in myofibroblasts) and 24 h, but not at 72 h. Both IPF and control cultures incubated with TGF-β1 for 72 h showed diminished COX-2 induction, PGE2 secretion and α-SMA expression after IL-1β addition. The latter decreased proliferation in fibroblasts but not in myofibroblasts. A549 cells incubated with TGF-β1 for 72 h showed down-regulated COX-2 expression and low basal PGE2 secretion in response to IL-1β. Immuno-histochemical analysis of IPF lung tissue showed no COX-2 immuno-reactivity in myofibroblast foci. Conclusions Myofibroblasts are associated with COX-2 down-regulation and reduced PGE2 production, which could be crucial in IPF development and progression. PMID:23755232

  5. Pregnancy rates to timed artificial insemination in Holstein heifers given prostaglandin F2alpha twenty-four hours before or concurrent with removal of an intravaginal progesterone-releasing insert.

    PubMed

    Ambrose, D J; Emmanuel, D G V; Colazo, M G; Kastelic, J P

    2008-07-01

    The objective was to compare pregnancy rates in nulliparous Holstein heifers given PGF(2alpha) 24 h before, or concurrent with, removal of an intravaginal progesterone-releasing (CIDR) insert in 3 timed artificial insemination (TAI) protocols. Heifers (from 2 herds) were assigned randomly, over 11 mo, to 1 of 3 modified Ovsynch protocols. On d 0 (without reference to the stage of the estrous cycle), all heifers were given 100 microg of GnRH i.m. and a CIDR insert (containing 1.9 g of progesterone). In the PG-7/P4-8 protocol (n = 99), PGF(2alpha) was given on d 7, and CIDR inserts were removed on d 8. In the PG-7/P4-7 (n = 98) and PG-8/P4-8 (n = 102) protocols, PGF(2alpha) administration and CIDR removal occurred concurrently, on d 7 or 8, respectively. In all 3 protocols, a second GnRH treatment (100 microg) was given 48 h after PGF(2alpha) with TAI 16 to 20 h later. Blood samples were collected (subset of 124 heifers) on d 0, 7, 10 or 11 (i.e., at TAI), and 17. Pregnancy rates (32 d after TAI) for protocols PG-7/P4-8, PG-7/P4-7, and PG-8/P4-8 were 61.8, 55.6, and 54.1%, respectively. Pregnancy rate was higher when synchronization was initiated during diestrus than when initiated at other stages (57.0 versus 34.8%). Although pregnancy rates were not affected by season, there was an interaction between protocol and season; pregnancy rates were significantly lower in summer in heifers subjected to PG-7/P4-7 and PG-8/P4-8, but season did not affect pregnancy rates in heifers subjected to PG-7/P4-8. In summary, giving PGF(2alpha) 24 h before CIDR removal, followed by TAI (PG-7/P4-8 protocol), resulted in consistent pregnancy rates, regardless of season, relative to protocols involving PGF(2alpha) treatment concurrent with CIDR removal. PMID:18565926

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

    PubMed

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

    2007-01-01

    The objectives of this study were to 1) compare cumulative pregnancy rates in a traditional management (TM) scheme with those using a synchronization of ovulation protocol (CO-Synch + CIDR) for timed AI (TAI) in Bos indicus-influenced cattle; 2) evaluate ovarian and hormonal events associated with CO-Synch + CIDR and CO-Synch without CIDR; and 3) determine estrual and ovulatory distributions in cattle synchronized with Select-Synch + CIDR. The CO-Synch + CIDR regimen included insertion of a controlled internal drug-releasing device (CIDR) and an injection of GnRH (GnRH-1) on d 0, removal of the CIDR and injection of PGF2alpha (PGF) on d 7, and injection of GnRH (GnRH-2) and TAI 48 h later. For Exp. 1, predominantly Brahman x Hereford (F1) and Brangus females (n = 335) were stratified by BCS, parity, and day postpartum (parous females) before random assignment to CO-Synch + CIDR or TM. To maximize the number of observations related to TAI conception rate (n = 266), an additional 96 females in which TM controls were not available for comparison also received CO-Synch + CIDR. Conception rates to TAI averaged 39 +/- 3% and were not affected by location, year, parity, AI sire, or AI technician. Cumulative pregnancy rates were greater (P < 0.05) at 30 and 60 d of the breeding season in CO-Synch + CIDR (74.1 and 95.9%) compared with TM (61.8 and 89.7%). In Exp. 2, postpartum Brahman x Hereford (F1) cows (n = 100) were stratified as in Exp. 1 and divided into 4 replicates of 25. Within each replicate, approximately one-half (12 to 13) received CO-Synch + CIDR, and the other half received CO-Synch only (no CIDR). No differences were observed between treatments, and the data were pooled. Percentages of cows ovulating to GnRH-1, developing a synchronized follicular wave, exhibiting luteal regression to PGF, and ovulating to GnRH-2 were 40 +/- 5, 60 +/- 5, 93 +/- 2, and 72 +/- 4%, respectively. In Exp. 3, primiparous Brahman x Hereford, (F1) heifers (n = 32) and pluriparous cows (n = 18) received the Select Synch + CIDR synchronization regimen (no GnRH-2 or TAI). Mean intervals from CIDR removal to estrus and ovulation, and from estrus to ovulation were 70 +/- 2.9, 99 +/- 2.8, and 29 +/- 2.2 h, respectively. These results indicate that the relatively low TAI conception rate observed with CO-Synch + CIDR in these studies was attributable primarily to failure of 40% of the cattle to develop a synchronized follicular wave after GnRH-1 and also to inappropriate timing of TAI/GnRH-2. PMID:17179551

  7. Estrous behavior and the estrus-to-ovulation interval in Nelore cattle (Bos indicus) with natural estrus or estrus induced with prostaglandin F2 alpha or norgestomet and estradiol valerate.

    PubMed

    Pinheiro, O L; Barros, C M; Figueiredo, R A; do Valle, E R; Encarnação, R O; Padovani, C R

    1998-02-01

    Estrous behavior and the estrus-to-ovulation interval are essential for estimating the best time to artificially inseminate cattle. Because these parameters are not well characterized in the Nelore breed (Bos indicus), the main purpose of the this study was to determine the estrus-to-ovulation interval in Nelore heifers and cows with natural estrus or with estrus induced by treatments with PGF2 alpha or norgestomet and estradiol valerate (NEV). The cows and heifers were observed continuously (24 h a day) to determine the onset of estrus and to study estrous behavior in the cows. Ten hours after the start of estrus the ovaries were scanned every 2 h by ultrasonography to monitor the dominant follicle until ovulation. Blood samples were collected periodically to determine progesterone levels by RIA. Administration of PGF2 alpha (2 injections, 11 days apart) did not induce estrus in most Nelore females in spite of the presence of functional CL, indicated by progesterone concentrations above 6.0 ng/ml in 25 of 28 animals. Treatment with NEV induced high sexual receptivity in cows (10/11), but only 66% ovulated. Cows with natural or induced estrus exhibited behavioral estrus of 10.9 +/- 1.4 h, and ovulation occurred 26.6 +/- 0.44 h (n = 26) after the onset of estrus. In most of the cows (53.8%) estrus began at night (between 1801 and 600 h), and 34.6% it started and finished during the night. It is concluded that in Nelore females ovulation occurs approximately 26 h after the onset of estrus. Additionally, estrous behavior is shorter than in European breeds, and there is a high incidence of estrus at night, which makes it difficult to detect and, consequently, impairs Al in Nelore cattle. The observation that a high percentage of Nelore females with an active CL did not respond to usual dosages of PGF2 alpha warrants further investigation. PMID:10732045

  8. Prostaglandin E2 production and metabolism in human breast cancer cells and breast fibroblasts. Regulation by inflammatory mediators.

    PubMed Central

    Schrey, M. P.; Patel, K. V.

    1995-01-01

    Malignant human breast tumours contain high levels of prostaglandin E2 (PGE2). However, the mechanisms controlling PGE2 production in breast cancer are unknown. This in vitro study investigates the capacity for PGE2 synthesis and metabolism in several human breast cancer cell lines and early passage human breast fibroblasts and seeks to identify potential regulatory factors which may control these pathways. Basal PGE2 production rose up to 30-fold in breast fibroblast lines on addition of exogenous arachidonic acid (10 microM), whereas no such changes were observed in six out of seven cancer cell lines, with the exception of modest increases in MDA-MB-231 cells. Interleukin 1 beta (IL-1 beta) also induced PGE2 production in breast fibroblasts in the presence of excess substrate, consistent with cyclo-oxygenase induction by the cytokine. Under these conditions only Hs578T cells and MDA-MB-231 cells demonstrated large increases in PGE2 in response to IL-1 beta or phorbol ester; no such responses were seen in MCF-7, T47-D, ZR-75-1, BT-20 or CLF-90-1 cells. In the absence of added arachidonate, bradykinin (BK) and endothelin-1 (ET-1), potentiated PGE2 production in IL-1 beta-treated fibroblasts, possibly by mobilising endogenous substrate. PGE2 also stimulated ET-1 production by breast cancer cells. In co-cultures with T47-D cells both basal and stimulated PGE2 production by breast fibroblasts was greatly reduced. This appeared to be due to metabolic inactivation by the cancer cell since T47-D cells readily converted PGE2 to 15-keto-PGE2. This apparent 15-hydroxy-PG dehydrogenase activity was stimulated by TPA and inhibited by cycloheximide. In conclusion, breast fibroblasts, particularly under the influence of inflammatory mediators, provide a potentially rich source for PGE2 production in breast tumours, whereas significant contributions from the epithelial tumour component may be restricted to cancer cells exhibiting an invasive phenotype. Metabolic inactivation by

  9. ERβ- and prostaglandin E2-regulated pathways integrate cell proliferation via Ras-like and estrogen-regulated growth inhibitor in endometriosis.

    PubMed

    Monsivais, D; Dyson, M T; Yin, P; Coon, J S; Navarro, A; Feng, G; Malpani, S S; Ono, M; Ercan, C M; Wei, J J; Pavone, M E; Su, E; Bulun, S E

    2014-08-01

    In endometriosis, stromal and epithelial cells from the endometrium form extrauterine lesions and persist in response to estrogen (E2) and prostaglandin E2 (PGE2). Stromal cells produce excessive quantities of estrogen and PGE2 in a feed-forward manner. However, it is unknown how estrogen stimulates cell proliferation and survival for the establishment and persistence of disease. Previous studies suggest that estrogen receptor-β (ERβ) is strikingly overexpressed in endometriotic stromal cells. Thus, we integrated genome-wide ERβ binding data from previously published studies in breast cells and gene expression profiles in human endometriosis and endometrial tissues (total sample number = 81) and identified Ras-like, estrogen-regulated, growth inhibitor (RERG) as an ERβ target. Estradiol potently induced RERG mRNA and protein levels in primary endometriotic stromal cells. Chromatin immunoprecipitation demonstrated E2-induced enrichment of ERβ at the RERG promoter region. PGE2 via protein kinase A phosphorylated RERG and enhanced the nuclear translocation of RERG. RERG induced the proliferation of primary endometriotic cells. Overall, we demonstrated that E2/ERβ and PGE2 integrate at RERG, leading to increased endometriotic cell proliferation and represents a novel candidate for therapeutic intervention. PMID:24992181

  10. Arachidonic acid release and prostaglandin synthesis in a macrophage-like cell line exposed to asbestos.

    PubMed

    Brown, R C; Poole, A

    1984-10-01

    A macrophage-like cell line (P388D1) has been treated with asbestos and the release of arachidonic acid and its metabolites has been studied using two methods. In the first monolayer cultures of the cells were labelled with tritiated arachidonic acid and the release of label into the medium was quantified: secondly the synthesis and release of prostaglandins E2 and F2 alpha were followed using radioimmune assay. Crocidolite asbestos caused the greatest release of tritium while the medium from chrysotile-treated cultures contained more of both prostaglandins. Both of the fibrous dusts were significantly more active in both test systems than were the two 'inert' materials--titanium dioxide and milled sample of crocidolite. It is suggested that these phenomena are due to the effect of mineral dusts on phospholipase activity and that differences in this activity are associated with differences in the pathogenicity of various mineral dusts. PMID:6098173

  11. The induced prostaglandin E2 pathway is a key regulator of the respiratory response to infection and hypoxia in neonates

    PubMed Central

    Hofstetter, Annika O.; Saha, Sipra; Siljehav, Veronica; Jakobsson, Per-Johan; Herlenius, Eric

    2007-01-01

    Infection during the neonatal period commonly induces apnea episodes, and the proinflammatory cytokine IL-1β may serve as a critical mediator between these events. To determine the mechanism by which IL-1β depresses respiration, we examined a prostaglandin E2 (PGE2)-dependent pathway in newborn mice and human neonates. IL-1β and transient anoxia rapidly induced brainstem-specific microsomal prostaglandin E synthase-1 (mPGES-1) activity in neonatal mice. Furthermore, IL-1β reduced respiratory frequency during hyperoxia and depressed hypoxic gasping and autoresuscitation in mPGES-1 wild-type mice, but not in mPGES-1 knockout mice. In wild-type mice, PGE2 induced apnea and irregular breathing patterns in vivo and inhibited brainstem respiratory rhythm generation in vitro. Mice lacking the EP3 receptor (EP3R) for PGE2 exhibited fewer apneas and sustained brainstem respiratory activity, demonstrating that PGE2 exerts its respiratory effects via EP3R. In human neonates, the infectious marker C-reactive protein was correlated with elevated PGE2 in the cerebrospinal fluid, and elevated central PGE2 was associated with an increased apnea frequency. We conclude that IL-1β adversely affects breathing and its control by mPGES-1 activation and PGE2 binding to brainstem EP3 receptors, resulting in increased apnea frequency and hypoxia-induced mortality. PMID:17535900

  12. Up-Regulation of Cyclooxygenase-2 Expression and Prostaglandin E2 Production in Human Endometriotic Cells by Macrophage Migration Inhibitory Factor: Involvement of Novel Kinase Signaling Pathways

    PubMed Central

    Carli, Cédric; Metz, Christine N.; Al-Abed, Yousef; Naccache, Paul H.; Akoum, Ali

    2009-01-01

    Cyclooxygenase (COX) is the rate-limiting enzyme in the metabolic conversion of arachidonic acid to prostaglandins (PGs), including prostaglandin E2 (PGE2), a major mediator of inflammation and angiogenesis. Herein, we report that macrophage migration inhibitory factor (MIF), a potent proinflammatory and growth-promoting factor found at elevated concentrations in the peritoneal fluid of women with endometriosis and active endometriosis lesions, acts directly on ectopic endometrial cells to stimulate the synthesis of COX-2, the inducible form of COX, and the release of PGE2. MIF treatment strongly activated p38 and ERK MAPK, and specific inhibitors of both pathways completely blocked basal and MIF-induced PGE2 synthesis. Whereas p38 inhibitors negatively affected the stimulated synthesis of COX-2 and that of PGE2, ERK inhibitors only decreased the production of PGE2. These findings show for the first time a direct role for MIF in the up-regulation of COX-2 synthesis and PGE2 secretion in ectopic endometrial cells. They further indicate that whereas p38 and ERK MAPK signaling pathways both play a significant role in the regulation of basal and MIF-induced synthesis of PGE2 by ectopic endometrial cells, only p38 kinase is involved in the regulation of COX-2 expression in these cells. This suggests that MIF acts at more than one level to stimulate the synthesis of PGE2 and triggers the coordinate activation of multiple enzymes in the biosynthesis pathway. Our data provide evidence for a novel mechanism by which MIF can induce a proinflammatory phenotype in ectopic endometrial cells, and favor the establishment of endometriosis and its related clinical symptoms. PMID:19299454

  13. 15-Deoxy-delta 12,14-prostaglandin J2 biphasically regulates the proliferation of mouse hippocampal neural progenitor cells by modulating the redox state.

    PubMed

    Katura, Takashi; Moriya, Takahiro; Nakahata, Norimichi

    2010-04-01

    The activity of neural progenitor cells (NPCs) is regulated by various humoral factors. Although prostaglandin (PG) D(2) is known to mediate various physiological brain functions such as sleep, its actions on NPCs have not been fully understood. In the process of investigating the effects of PGD(2) on NPCs, we found that 15-deoxy-Delta(12,14)-prostaglandin J(2) (15d-PGJ(2)), an endogenous metabolite of PGD(2), exhibits a novel regulation of the proliferation of NPCs derived from mouse hippocampus. 15d-PGJ(2) showed biphasic effects on epidermal growth factor-induced proliferation of NPCs; facilitation at low concentrations ( approximately 0.3 muM) and suppression at higher concentrations (0.5-10 microM) in vitro. 2-Chloro-5-nitrobenzanilide (GW9662), an inhibitor of peroxisome proliferator-activated receptor gamma, known to be a molecular target for 15d-PGJ(2), failed to abolish the effects of 15d-PGJ(2). 9,10-dihydro-15d-PGJ(2) (CAY10410), a structural analog of 15d-PGJ(2) lacking the electrophilic carbon in the cyclopentenone ring, did not show 15d-PGJ(2)-like actions. Treatment with 15d-PGJ(2) increased the levels of reactive oxygen species and decreased endogenous GSH levels. Furthermore, supplementation with a membrane-permeable analog of glutathione, GSH ethyl ester (2 mM), diminished the biphasic effects of 15d-PGJ(2). Finally, cell division in the dentate gyrus of postnatal mice was increased by injection of low-dose (1 ng i.c.v.) 15d-PGJ(2) and suppressed by high-dose (30 ng) 15d-PGJ(2). These results suggest that 15d-PGJ(2) regulates the proliferation of NPCs via its electrophilic nature, which enables covalent binding to molecules such as GSH. PMID:20086036

  14. On the ability of prostaglandin E1, and arachidonic acid to modulate experimentally induced oedema in the rat paw.

    PubMed Central

    Lewis, A J; Nelson, D J; Sugrue, M F

    1975-01-01

    1 Prostaglandins E1 and E2 but not prostaglandin F2alpha, arachidonic acid or linolenic acid, produced slight oedema when injected into the rat hindpaw. 2 Prostaglandin E1 potentiated hindpaw oedema produced by carrageenan, kaolin, bradykinin and trypsin but not that produced by 5-hydroxytryptamine (5-HT), histamine, dextran B or compound 48/80. Carrageenan- and bradykinin-induced paw oedemas were also potentiated by prostaglandin E2. Arachidonic acid potentiated responses to carrageenan and kaolin but not responses to bradykinin, trypsin, 5-HT, histamine, dextran B or compound 48/80. Linolenic acid did not potentiate hindpaw oedema induced by carrageenan. 3 Potentiation of carrageenan-induced oedema by prostaglandin E1 was not diminished by pretreatment with indomethacin, hydrocortisone or cyproheptadine. However, arachidonic acid potentiation of carrageenan oedema was reduced by pretreatment with non-steroidal anti-inflammatory drugs but not by anti-inflammatory steroids or by paracetamol. 4 The enhancement of the response to carrageenan and kaolin by prostaglandins E1, E2 and arachidonic acid is discussed in terms of kinin mediation. PMID:1182349

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

    PubMed Central

    Seebacher, Frank; Franklin, Craig E

    2003-01-01

    The effectiveness of behavioural thermoregulation in reptiles is amplified by cardiovascular responses, particularly by differential rates of heart beat in response to heating and cooling (heart-rate hysteresis). Heart-rate hysteresis is ecologically important in most lineages of ectothermic reptile, and we demonstrate that heart-rate hysteresis in the lizard Pogona vitticeps is mediated by prostaglandins. In a control treatment (administration of saline), heart rates during heating were significantly faster than during cooling at any given body temperature. When cyclooxygenase 1 and 2 enzymes were inhibited, heart rates during heating were not significantly different from those during cooling. Administration of agonists showed that thromboxane B(2) did not have a significant effect on heart rate, but prostacyclin and prostaglandin F(2alpha) caused a significant increase (3.5 and 13.6 beats min(-1), respectively) in heart rate compared with control treatments. We speculate that heart-rate hysteresis evolved as a thermoregulatory mechanism that may ultimately be controlled by neurally induced stimulation of nitric oxide production, or maybe via photolytically induced production of vitamin D. PMID:12952634

  16. Comparative study of midtrimester termination of pregnancy using hypertonic saline, ethacridine lactate, prostaglandin analogue and iodine-saline.

    PubMed

    Allahbadia, G

    1992-09-01

    The study consisted of terminations of 200 cases of second trimester pregnancies ranging from 14 weeks to 20 weeks. Out of these 200 cases, in 50 cases intra-amniotic instillation of 20% hypertonic saline (200 ml) was done after withdrawing 35-200 ml of amniotic fluid. Ethacridine lactate was instilled in 50 cases extra-amniotically. Prostaglandin F2 alpha was injected intramuscularly at regular intervals in 50 cases. Fifty cases of pregnancies were terminated with extra-amniotic instillation of 5% povidone-iodine solution mixed with normal saline. Comparison was made among all the methods regarding instillation-abortion interval, completeness of abortion, failure of the procedure and postoperative complications. Solution of 5% povidone-iodine in normal saline was found to be comparable in all aspects to other methods and above all a much cheaper alternative for poor patients. Success rate was highest with iodine-saline solution (100%) followed by ethacridine lactate (98%), hypertonic saline (96%) and lowest with prostaglandin F2 alpha (90%). PMID:1460314

  17. MicroRNA 21 Is a Homeostatic Regulator of Macrophage Polarization and Prevents Prostaglandin E2-Mediated M2 Generation

    PubMed Central

    Wang, Zhuo; Brandt, Stephanie; Medeiros, Alexandra; Wang, Soujuan; Wu, Hao; Dent, Alexander; Serezani, C. Henrique

    2015-01-01

    Macrophages dictate both initiation and resolution of inflammation. During acute inflammation classically activated macrophages (M1) predominate, and during the resolution phase alternative macrophages (M2) are dominant. The molecular mechanisms involved in macrophage polarization are understudied. MicroRNAs are differentially expressed in M1 and M2 macrophages that influence macrophage polarization. We identified a role of miR-21 in macrophage polarization, and found that cross-talk between miR-21 and the lipid mediator prostaglandin E2 (PGE2) is a determining factor in macrophage polarization. miR-21 inhibition impairs expression of M2 signature genes but not M1 genes. PGE2 and its downstream effectors PKA and Epac inhibit miR-21 expression and enhance expression of M2 genes, and this effect is more pronounced in miR-21-/- cells. Among potential targets involved in macrophage polarization, we found that STAT3 and SOCS1 were enhanced in miR-21-/- cells and further enhanced by PGE2. We found that STAT3 was a direct target of miR-21 in macrophages. Silencing the STAT3 gene abolished PGE2-mediated expression of M2 genes in miR-21-/- macrophages. These data shed light on the molecular brakes involved in homeostatic macrophage polarization and suggest new therapeutic strategies to prevent inflammatory responses. PMID:25706647

  18. Reactive oxygen species (ROS) production triggered by prostaglandin D2 (PGD2) regulates lactate dehydrogenase (LDH) expression/activity in TM4 Sertoli cells.

    PubMed

    Rossi, Soledad P; Windschüttl, Stefanie; Matzkin, María E; Rey-Ares, Verónica; Terradas, Claudio; Ponzio, Roberto; Puigdomenech, Elisa; Levalle, Oscar; Calandra, Ricardo S; Mayerhofer, Artur; Frungieri, Mónica B

    2016-10-15

    Reactive oxygen species (ROS) regulate testicular function in health and disease. We previously described a prostaglandin D2 (PGD2) system in Sertoli cells. Now, we found that PGD2 increases ROS and hydrogen peroxide (H2O2) generation in murine TM4 Sertoli cells, and also induces antioxidant enzymes expression suggesting that defense systems are triggered as an adaptive stress mechanism that guarantees cell survival. ROS and specially H2O2 may act as second messengers regulating signal transduction pathways and gene expression. We describe a stimulatory effect of PGD2 on lactate dehydrogenase (LDH) expression via DP1/DP2 receptors, which is prevented by the antioxidant N-acetyl-L-cysteine and the PI3K/Akt pathway inhibitor LY 294002. PGD2 also enhances Akt and CREB/ATF-1 phosphorylation. Our results provide evidence for a role of PGD2 in the regulation of the oxidant/antioxidant status in Sertoli cells and, more importantly, in the modulation of LDH expression which takes place through ROS generation and the Akt-CREB/ATF-1 pathway. PMID:27329155

  19. Apoptosis induction by glycoprotein isolated from Laminaria japonica is associated with down-regulation of telomerase activity and prostaglandin E2 synthesis in AGS human gastric cancer cells.

    PubMed

    Han, Min Ho; Kim, Gi Young; Moon, Sung-Kwon; Kim, Wun-Jae; Nam, Taek-Jeong; Choi, Yung Hyun

    2011-02-01

    Glycoprotein isolated from Laminaria japonica (LJGP) is known to exhibit significant cytotoxic activity against human cancer cells; however, the mechanisms of its cytoxicity are poorly understood. In this study, we investigated further possible mechanisms by which LJGP exerts its anti-cancer action in cultured human gastric carcinoma AGS cells. LJGP treatment of AGS cells resulted in inhibition of growth and induction of apoptosis in a time- and concentration-dependent manner, as determined by MTT assay, fluorescence microscopy, and flow cytometry analysis. The increase in apoptosis was associated with up-regulation of pro-apoptotic Bax expression, down-regulation of anti-apoptotic Bcl-2 and IAP family members, and activation of caspase-3 and -9. LJGP treatment markedly down-regulated the activity of telomerase and expression of human telomerase reverse transcriptase, a main determinant of telomerase enzymatic activity, with inhibition of Sp1 and c-Myc expression in a concentration-dependent manner. Furthermore, LJGP treatment also caused a progressive decrease in the expression levels of cyclooxygenase (COX)-2 without significant changes in the levels of COX-1, which was correlated with a decrease in prostaglandin E2 synthesis. These results provide important new insights into the possible molecular mechanisms of the anti-cancer activity of LJGP. PMID:21132266

  20. Prostaglandin E2 inhibits IL-23 and IL-12 production by human monocytes through down-regulation of their common p40 subunit.

    PubMed

    Kalim, Khalid W; Groettrup, Marcus

    2013-03-01

    The heterodimeric cytokine IL-23 is important for the maintenance of Th17 cells, which are pivotal mediators of autoimmune diseases like rheumatoid arthritis, colitis, and multiple sclerosis. Prostaglandin E2 (PGE2) is a soluble regulator of inflammation that has both pro- and anti-inflammatory properties. PGE2 has been shown to elevate the IL-23 production by dendritic cells (DC). Monocytes are also producers of IL-23 but the effect of PGE2 on IL-23 production by human monocytes has hardly been investigated. We show here that PGE2 blocks the production of IL-23 by LPS-stimulated monocytes in an IL-10 and IL-1β independent manner. This effect was due to the down-regulation of the p40 subunit of IL-23 on mRNA and protein level. The p40 subunit is shared by IL-12 and, consistently, PGE2 also lowered the IL-12 production by monocytes. These effects of PGE2 were cAMP-dependent since the cAMP enhancer forskolin strongly reduced IL-23 and IL-12 production by monocytes. Taken together, PGE2 acts in an anti-inflammatory manner by lowering IL-23 production by monocytes while it has the opposite effect in DC. Our data may help to reconcile controversial point of views on the pro- and anti-inflammatory nature of PGE2 by making a strong case for a cell type-dependent function. PMID:22982753

  1. Metastasis-associated protein 1 (MTA1) signaling in rheumatoid synovium: Regulation of inflammatory response and cytokine-mediated production of prostaglandin E2 (PGE2).

    PubMed

    Wang, Hui; Dong, Bing-Wei; Zheng, Zhao-Hui; Wu, Zhen-Biao; Li, Wei; Ding, Jin

    2016-04-29

    Abnormal perpetual inflammatory response and sequential cytokine-induced prostaglandin E2 (PGE2) play important roles in the pathogenesis of rheumatoid arthritis (RA). The underlying regulatory mechanism, however, remain largely unknown. Here, we discovered that expression level of Metastasis associated protein 1 (MTA1), an important chromatin modifier that plays a critical role in transcriptional regulation by modifying DNA accessibility for cofactors, was upregulated in human rheumatoid synovial tissues. Furthermore, a knockdown of MTA1 by siRNA in the human fibroblast-like synovial cell line MH7A was found to impair the 4-hydroxynonenal (4-HNE)-induced transcriptional expression levels of certain proinflammatory cytokines including IL-1β, TNF-α and IL-6. Moreover, endogenous MTA1 was required for the cytokines-induced PGE2 synthesis by rheumatoid synoviocytes. Collectively, the coordinated existence of MTA1 inside distinct cascade loops points to its indispensable role in the modulation of the integrated cytokine network along the pathogenesis of RA. Further exploration of the functional details of this master transcriptional regulator should be an attractive strategy to identify novel therapeutic target for RA and warrants execution. PMID:26970310

  2. HtrA3 is regulated by 15-deoxy-{Delta}12,14-prostaglandin J2 independently of PPAR{gamma} in clear cell renal cell carcinomas

    SciTech Connect

    Theoleyre, Sandrine; Mottier, Stephanie; Masson, Damien; Denis, Marc G.

    2010-04-09

    Peroxisome proliferator-activated receptor gamma (PPAR{gamma}) ligands have been shown to possess anti-proliferative effects in many types of cancer. In clear cell renal cell carcinoma (CCRCC), the targets involved in these effects are not known. In this study, we demonstrated that, in CCRCC cell lines, the endogenous PPAR{gamma} ligand 15-deoxy-{Delta}12,14-prostaglandin J2 (15dPGJ2) induces the expression, both at the mRNA and the protein levels, of the HtrA3 gene. This gene belongs to the High-Temperature Requirement Factor A family of serine proteases that repress signaling by TGF-{beta} family members and inhibit cell migration. Rosiglitazone or ciglitazone, synthetic PPAR{gamma} agonists, did not induce HtrA3 expression, and the PPAR{gamma} antagonist GW9662 did not prevent 15dPGJ2 induction, suggesting that the up-regulation of HtrA3 by 15dPGJ2 is independent of PPAR{gamma}. The MEK/ERK inhibitor PD98059 dramatically repressed HtrA3 induction. Altogether, these data indicate that 15dPGJ2 is able to stimulate the expression of HtrA3 through an indirect mechanism involving the MEK/ERK pathway but independent of PPAR{gamma}. Our results provide a better understanding of the mechanisms involved in the regulation of HtrA3, a potential tumor suppressor gene.

  3. Prostaglandins, endotoxin and lipid A on body temperature in rats.

    PubMed Central

    Feldberg, W; Saxena, P N

    1975-01-01

    1. In unanaesthetized restrained rats kept at an ambient temperature of 21-23degrees C, rectal temperature was continuously monitored and the temperature effects of injections of prostaglandins, endotoxin from Salmonella abortus equi, lipid A, and antipyretics were examined. 2. Fever occurred when prostaglandin E1, E2, F1alpha or F2alpha (PGE1, PGE2, PGF1alpha, PGF2alpha) was injected into the cerebral ventricles in doses of 200 ng and 2 mug. PGE2 was the most potent prostaglandin followed in descending order by PGE1, PGF2alpha, and PGF1alpha. The fever produced by 2 mug of PGE1 and PGE2 was short and followed by a fall in temperature to below the pre-injection level. 3. I.V. injections of endotoxin and lipid A in doses of 3 or 10 mug usually caused a long lasting fall in temperature, but when injected into the cerebral ventricles in doses of 400 ng or 1 mug, they produced long lasting fevers. 4. Injected I.V. or I.P., indomethacin and paracetamol had a hypothermic action of their own. Indomethacin was more potent than paracetamol and both were more potent than injected I.P. 5. I.V. and I.P. injections of indomethacin and paracetamol did not reverse the hypothermia in response to I.V. endotoxin or lipid A, but the fever responses to their injection into the cerebral ventricles were prevented and abolished by the antipyretics. 6. It is concluded that in rats endotoxin and lipid A, or the endogenous pyrogens produced by them, do not readily pass through the blood-brain barrier into the brain tissue. If they do reach brain tissue, as when injected into the cerebral ventricles, they stimulate synthesis and release of prostaglandin in rats as they do in other species, and thereby produce fever. The hypothermia in response to I.V. endotoxin or lipid A, on the other hand, is thought to be independent of prostaglandin synthesis and to result from a direct toxic action on the skin vessels. PMID:1177107

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

    NASA Technical Reports Server (NTRS)

    Hughes-Fulford, M.

    1994-01-01

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

  5. Regulation of activator protein-1 by 8-iso-prostaglandin E2 in a thromboxane A2 receptor-dependent and -independent manner

    SciTech Connect

    Weber, Thomas J.; Markillie, Lye MENG.

    2003-05-01

    The thromboxane (TX) A{sub 2} receptor (TP) encompasses two alternatively spliced forms, termed the platelet/placental (TP-P) and endothelial (TP-E) type receptors. Experimental evidence suggests that TP activity may be modulated by novel ligands, termed the isoprostanes, that paradoxically act as TP agonists in smooth muscle and TP antagonists in platelet preparations. Here we have investigated whether prototypical isoprostanes 8-iso-prostaglandin (PG)F{sub 2{alpha}} and 8-iso-PGE{sub 2} regulate the activity of TP isoforms expressed in Chinese hamster ovary (CHO) cells using activator protein-1 (AP-1)-luciferase activity as a reporter. AP-1-luciferase activity was increased by a TP agonist [9,11-dideoxy-9{alpha},11{alpha}-methanoepoxy PGF{sub 2{alpha}} (U46619)] in CHO cells transfected with the human TP-P and TP-E receptors, and this response was fully inhibited by TP antagonists [1S-[1{alpha},2{beta}(Z),3{alpha},5{alpha}

  6. 15-Deoxy-{delta}{sup 12,14}-prostaglandin J{sub 2}-induced down-regulation of endothelial nitric oxide synthase in association with HSP70 induction

    SciTech Connect

    Hwang, Jinah; Lee, Hyun-Il; Chang, Young-Sun; Lee, Soo Jae; Kim, Kwang Pyo; Park, Sang Ick . E-mail: parksi@nih.go.kr

    2007-05-25

    A natural ligand of peroxisome proliferator-activated receptor {gamma} (PPAR{gamma}), 15-deoxy-{delta}{sup 12,14}-prostaglandin J{sub 2} (15d-PGJ{sub 2}), decreases endothelial nitric oxide synthase (eNOS) expression by an unknown mechanism. Here we found that 15d-PGJ{sub 2}-induced eNOS reduction is inversely associated with heat shock protein 70 (HSP70) induction in endothelial cells. Treatment of cells with 15d-PGJ{sub 2} decreased eNOS protein expression in a concentration- and time-dependent manner, but independently of PPAR{gamma} with no effect on mRNA levels. Although 15d-PGJ{sub 2} elicited endothelial apoptosis, inhibition of both pan-caspases and cathepsins failed to reverse reduction of eNOS protein. Interestingly, we observed that 15d-PGJ{sub 2} induced HSP70 in a dose-dependent manner. Immunoprecipitation and heat shock treatment demonstrated that eNOS reduction was strongly related to HSP70 induction. Cellular fractionation revealed that treatment with 15d-PGJ{sub 2} increased eNOS distribution 2.5-fold from soluble to insoluble fractions. These findings provide new insights into mechanisms whereby eNOS regulation by 15d-PGJ{sub 2} is related to HSP70 induction.

  7. 15-Deoxy-{delta}{sup 12,14}-Prostaglandin J{sub 2} regulates leukemia inhibitory factor signaling through JAK-STAT pathway in mouse embryonic stem cells

    SciTech Connect

    Rajasingh, Johnson; Bright, John J. . E-mail: jbright1@clarian.org

    2006-08-01

    Embryonic stem (ES) cells are genetically normal, pluripotent cells, capable of self-renewal and differentiation into all cell lineages. While leukemia inhibitory factor (LIF) maintains pluripotency in mouse ES cells, retinoic acid and other nuclear hormones induce neuro-glial differentiation in mouse and human ES cells in culture. Peroxisome-proliferator-activated receptors (PPARs) are ligand-dependent nuclear receptor transcription factors that regulate cell growth and differentiation in many cell types. However, the role of PPARs in the regulation of ES cell growth and differentiation is not known. In this study, we show that LIF induces proliferation and self-renewal of mouse D3-ES cells in culture. However, treatment with 15-Deoxy-{delta}{sup 12,14}-Prostaglandin J{sub 2} (15d-PGJ2), a natural ligand for PPAR{gamma}, or all-trans retinoic acid (ATRA) results in a dose-dependent decrease in proliferation and self-renewal in D3-ES cells. Immunoprecipitation and Western blot analyses showed that LIF induces tyrosine phosphorylation of JAK1, TYK2 and STAT3 in 30 min and treatment with 15d-PGJ2 or ATRA results in a dose-dependent decrease in LIF-induced phosphorylation of JAK1 and STAT3 in D3-ES cells. However, treatment of D3-ES cells with Ciglitazone or 15d-PGJ2 for 48 h in culture resulted in a dose-dependent increase in PPAR{gamma} protein expression. These results suggest that PPAR{gamma} agonists regulate LIF signaling through JAK-STAT pathway leading to growth and self-renewal of ES cells.

  8. Transcription of Liver X Receptor Is Down-Regulated by 15-Deoxy-Δ12,14-Prostaglandin J2 through Oxidative Stress in Human Neutrophils

    PubMed Central

    Alba, Gonzalo; Reyes, María Edith; Santa-María, Consuelo; Ramírez, Remedios; Geniz, Isabel; Jiménez, Juan; Martín-Nieto, José; Pintado, Elízabeth; Sobrino, Francisco

    2012-01-01

    Liver X receptors (LXRs) are ligand-activated transcription factors of the nuclear receptor superfamily. They play important roles in controlling cholesterol homeostasis and as regulators of inflammatory gene expression and innate immunity, by blunting the induction of classical pro-inflammatory genes. However, opposite data have also been reported on the consequences of LXR activation by oxysterols, resulting in the specific production of potent pro-inflammatory cytokines and reactive oxygen species (ROS). The effect of the inflammatory state on the expression of LXRs has not been studied in human cells, and constitutes the main aim of the present work. Our data show that when human neutrophils are triggered with synthetic ligands, the synthesis of LXRα mRNA became activated together with transcription of the LXR target genes ABCA1, ABCG1 and SREBP1c. An inflammatory mediator, 15-deoxy-Δ12,14-prostaglandin J2 (15dPGJ2), hindered T0901317-promoted induction of LXRα mRNA expression together with transcription of its target genes in both neutrophils and human macrophages. This down-regulatory effect was dependent on the release of reactive oxygen species elicited by 15dPGJ2, since it was enhanced by pro-oxidant treatment and reversed by antioxidants, and was also mediated by ERK1/2 activation. Present data also support that the 15dPGJ2-induced serine phosphorylation of the LXRα molecule is mediated by ERK1/2. These results allow to postulate that down-regulation of LXR cellular levels by pro-inflammatory stimuli might be involved in the development of different vascular diseases, such as atherosclerosis. PMID:23115616

  9. Anuran calling circuits: inhibition of pretrigeminal nucleus by prostaglandin.

    PubMed

    Schmidt, R S

    1993-03-01

    Neural correlates of mating calling and pulmonary respiration were recorded from isolated brain stems of male Northern leopard frogs (Rana p. pipiens) before and after exposure of the brain stems to prostaglandin F2 alpha (PG) or saline. Diffusion of PG (but not saline) from a pipette directly over the pretrigeminal nuclei abolished "calling" temporarily. Similar application of PG nearby had no effect. Exposure of only the anterior 1/2 of the brain stem, containing the pretrigeminal nuclei but not the pulmonary respiration generator, to PG (but not saline) abolished generation of slow waves by the pretrigeminal nucleus portion of the mating calling pattern generator. Exposure of only the posterior 1/2 of the brain stem, containing the pulmonary respiration generator but not the pretrigeminal nuclei, to PG had no effect on the correlates of pulmonary respiration. These results are consistent with the hypothesis that the inhibition of calling by PG is through an effect largely, perhaps exclusively, on the pretrigeminal nuclei. PMID:8440519

  10. Cannabinoid Receptor-2 Regulates Embryonic Hematopoietic Stem Cell Development via Prostaglandin E2 and P-Selectin Activity.

    PubMed

    Esain, Virginie; Kwan, Wanda; Carroll, Kelli J; Cortes, Mauricio; Liu, Sarah Y; Frechette, Gregory M; Sheward, Lea M V; Nissim, Sahar; Goessling, Wolfram; North, Trista E

    2015-08-01

    Cannabinoids (CB) modulate adult hematopoietic stem and progenitor cell (HSPCs) function, however, impact on the production, expansion, or migration of embryonic HSCs is currently uncharacterized. Here, using chemical and genetic approaches targeting CB-signaling in zebrafish, we show that CB receptor (CNR) 2, but not CNR1, regulates embryonic HSC development. During HSC specification in the aorta-gonad-mesonephros (AGM) region, CNR2 stimulation by AM1241 increased runx1;cmyb(+) HSPCs, through heightened proliferation, whereas CNR2 antagonism decreased HSPC number; FACS analysis and absolute HSC counts confirmed and quantified these effects. Epistatic investigations showed AM1241 significantly upregulated PGE2 synthesis in a Ptgs2-dependent manner to increase AGM HSCs. During the phases of HSC production and colonization of secondary niches, AM1241 accelerated migration to the caudal hematopoietic tissue (CHT), the site of embryonic HSC expansion, and the thymus; however these effects occurred independently of PGE2. Using a candidate approach for HSC migration and retention factors, P-selectin was identified as the functional target of CNR2 regulation. Epistatic analyses confirmed migration of HSCs into the CHT and thymus was dependent on CNR2-regulated P-selectin activity. Together, these data suggest CNR2-signaling optimizes the production, expansion, and migration of embryonic HSCs by modulating multiple downstream signaling pathways. PMID:25931248

  11. Prostamides (prostaglandin-ethanolamides) and their pharmacology.

    PubMed

    Woodward, D F; Liang, Y; Krauss, A H-P

    2008-02-01

    The prostamides are part of a large and continually expanding series of pharmacologically unique neutral lipids. They are COX-2 derived oxidation products of the endocannabinoid/endovanniloid anandamide. Prostamide pharmacology is unique and, as in the case of the endocannabinoids anandamide and 2-arachidonylglycerol, bears little resemblance to that of the corresponding free acids. By virtue of its close relationship to the anti-glaucoma drug bimatoprost, prostamide F(2alpha) has received the greatest research attention. Prostamide F(2alpha) and bimatoprost effects appear independent of prostanoid FP receptor activation, according to a litany of agonist studies. Studies involving freshly isolated and separate feline iridial smooth muscle cells revealed that bimatoprost and FP receptor agonists stimulated different cells, without exception. This suggests the existence of receptors that preferentially recognize prostamide F(2alpha). The recent discovery of prostamide antagonists has provided further support for prostamide receptors as discrete entities. The prototypical prostamide antagonists, AGN 204396 and 7, blocked the effects of prostamide F(2alpha) and bimatoprost but not those of PGF(2alpha) and FP receptor agonists in the feline iris. Second generation more potent prostamide antagonists, such as AGN 211334, should allow the role of prostamides in health and disease to be elucidated. From the therapeutics standpoint, the prostamide F(2alpha) analogue bimatoprost is the most efficacious ocular hypotensive agent currently available for the treatment of glaucoma. PMID:17721551

  12. Successful induction of sclerostin in human-derived fibroblasts by 4 transcription factors and its regulation by parathyroid hormone, hypoxia, and prostaglandin E2.

    PubMed

    Fujiwara, Makoto; Kubota, Takuo; Wang, Wei; Ohata, Yasuhisa; Miura, Kohji; Kitaoka, Taichi; Okuzaki, Daisuke; Namba, Noriyuki; Michigami, Toshimi; Kitabatake, Yasuji; Ozono, Keiichi

    2016-04-01

    Sclerostin, coded by SOST, is a secretory protein that is specifically expressed in osteocytes and suppresses osteogenesis by inhibiting WNT signaling. The regulatory mechanism underlying SOST expression remains unclear mainly due to the absence of an adequate human cell model. Thus, we herein attempted to establish a cell model of human dermal fibroblasts in order to investigate the functions of sclerostin. We selected 20 candidate transcription factors (TFs) that induce SOST expression by analyzing gene expression patterns in the human sarcoma cell line, SaOS-2, between differentiation and maintenance cultures using microarrays. An effective set of TFs to induce SOST expression was sought by their viral transduction into fibroblasts, and a combination of four TFs: ATF3, KLF4, PAX4, and SP7, was identified as the most effective inducer of SOST expression. Quantitative PCR demonstrated that the expression levels of SOST in fibroblasts treated with the 4 TFs were 199- and 1439-fold higher than those of the control after 1-week and 4-week cultures, respectively. The level of sclerostin in the conditioned medium, as determined by ELISA, was 21.2pmol/l 4weeks after the transduction of the 4 TFs. Interestingly, the production of Dickkopf1 (DKK1), another secreted inhibitor of WNT signaling, was also increased by transduction of these 4 TFs. Parathyroid hormone (PTH) significantly suppressed the induced SOST by 38% and sclerostin by 82% that of the vehicle. Hypoxia increased the induced SOST by 62% that of normoxia. Furthermore, prostaglandin E2 (PGE2) increased SOST expression levels to 16-fold those of the vehicle. In conclusion, the efficient induction of SOST expression and sclerostin production was achieved in human dermal fibroblasts by the transduction of ATF3, KLF4, PAX4, and SP7, and the induced SOST and sclerostin were regulated by PTH, hypoxia, and PGE2. This model may contribute to elucidating the regulatory mechanisms underlying SOST expression and advancing

  13. Identification of the two-phase mechanism of arachidonic acid regulating inflammatory prostaglandin E2 biosynthesis by targeting COX-2 and mPGES-1.

    PubMed

    Akasaka, Hironari; Ruan, Ke-He

    2016-08-01

    Through linking inducible cyclooxygenase (COX)-2 with microsomal prostaglandin E2 (PGE2) synthase-1 (mPGES-1), a Single-Chain Enzyme Complex (SCEC, COX-2-10aa-mPGES-1) was engineered to mimic a specific inflammatory PGE2 biosynthesis from omega-6 fatty acid, arachidonic acid (AA), by eliminating involvements of non-inducible COX-1 and other PGE2 synthases. Using the SCEC, we characterized coupling reactions between COX-2 and mPGES-1 at 1:1 ratio of inflammatory PGE2 production. AA demonstrated two phase activities to regulate inflammatory PGE2 production. In the first phase (<2 μM), AA was a COX-2 substrate and converted to increasing production of PGE2. In the second phase with a further increased AA level (2-10 μM), AA bound to mPGES-1 and inhibited the PGE2 production. The SCEC study was identical to the co-expression of COX-2 and mPGES-1. This was further confirmed by using mPGES-1 and PGH2 as a direct enzyme target and substrate, respectively. Furthermore, the carboxylic acid group of AA binding to R67 and R70 of mPGES-1 was identified by X-ray structure-based docking and mutagenesis. mPGES-1 mutants, R70A, R70K, R67A and R67K, lost 40-100% binding to [(14)C]-AA. To conclude, a cellular model, in which AA is involved in self-controlling initial initiating and later resolving inflammation by its two phase activities, was discussed. PMID:27177970

  14. Prostaglandin E2 is a potent regulator of interleukin-12- and interleukin-18-induced natural killer cell interferon-γ synthesis

    PubMed Central

    Walker, William; Rotondo, Dino

    2004-01-01

    Synthesis of interferon (IFN)-γ by natural killer (NK) cells is an important pro-inflammatory event with interleukin (IL)-12 and IL-18 playing major inductive roles. However, other temporal events are likely to regulate such processes and as prostaglandin E2 (PGE2) is ubiquitous during inflammation this study tested the hypothesis that PGE2 was capable of directly modulating cytokine-induced NK cell IFN-γ synthesis in the absence of other immune cells. Using homogenous NK cell lines to establish direct effects, PGE2 (0·1–1 µm) was found to suppress NK cell IFN-γ synthesis and antagonized the potent synergistic IFN-γ-inducing effects of IL-12 and IL-18. The actions of PGE2 were mimicked by synthetic PGE2 analogues including misoprostol and butaprost. The selective EP2 receptor agonist butaprost, but not the EP1/EP3 agonist sulprostone, suppressed IFN-γ synthesis and exclusively competed with PGE2 for receptor binding on NK cells. Further analysis showed that PGE2 did not modulate IL-12 receptor mRNA expression and the effects of PGE2 could be mimicked by the phosphodiesterase inhibitor 3-iosobutyl-1-methylxanthine. The absence of demonstrable receptor modulation coupled with the observed suppression of IFN-γ synthesis by both EP2 receptor-selective agonists and IBMX suggest that PGE2 acts directly on NK cells via EP2 receptors with its downstream effects on cAMP metabolism. This conclusion is further supported by findings that PGE2 and its analogues consistently elevated levels of cAMP in NK cells. The ability of PGE2 to antagonize the potent inductive signal provided by the combination of IL-12 and IL-18 supports the concept that PGE2 may play an important role in limiting innate inflammatory processes in vivo through direct suppression of NK cell IFN-γ synthesis. PMID:15009430

  15. Cyclic mechanical stretching and interleukin-1alpha synergistically up-regulate prostacyclin secretion in cultured human uterine myometrial cells.

    PubMed

    Korita, D; Itoh, H; Sagawa, N; Yura, S; Yoshida, M; Kakui, K; Takemura, M; Nuamah, M A; Fujii, S

    2004-03-01

    Prostacyclin (PGI2), a potent uterine smooth muscle relaxant, is postulated to be a major prostaglandin (PG) secreted from the human myometrium. PGI2 metabolite concentrations in the maternal plasma were reported to be elevated during pregnancy, especially during labor. Recently, we developed cultured human myometrial cells from pregnant women and reported that cyclic mechanical stretching mimicking labor increased PGI2 secretion from these cells by up-regulating PGI2 synthase promoter activities. Since elevation of cervical/vaginal interleukin-1alpha (IL-1alpha) concentrations is also a characteristic feature of delivery, and IL-1alpha is a known stimulator of PG synthesis, we investigated a possible synergistic effect of cyclic mechanical stretching and IL-1alpha on PGI2 production in cultured human myometrial cells. Treatment with IL-1alpha (10 ng/ml) significantly augmented (4- to 60-fold) the secretion of PGI2, prostaglandin E2 (PGE2), prostaglandin F2alpha (PGF2alpha) and thromboxane A2 (TXA2) from cultured human myometrial cells obtained from non-pregnant and pregnant women as well as in cultured human umbilical artery and cultured human coronary artery smooth muscle cells (p < 0.05 for all comparisons). However, labor-like cyclic mechanical stretching up-regulated IL-1alpha-augmented PGI2 secretion from myometrial cells obtained from non-pregnant and pregnant women 2.1- to 2.8-fold (p < 0.05 for all comparisons), but not PGE2, PGF2alpha nor TXA2. Moreover, such an augumentation of PGI2 secretion by cyclic mechanical stretching was not observed in cultured human umbilical artery nor in cultured human coronary artery smooth muscle cells. These results suggest that cyclic mechanical stretching by labor, in concert with IL-1alpha stimulation, contributes to the increase in myometrial PGI2 secretion during delivery. PMID:15255281

  16. Prostaglandins and prostaglandin receptor antagonism in migraine.

    PubMed

    Antonova, Maria

    2013-05-01

    Human models of headache may contribute to understanding of prostaglandins' role in migraine pathogenesis. The current thesis investigated the migraine triggering effect of prostaglandin E2 (PGE2) in migraine patients without aura, the efficacy of a novel EP4 receptor antagonist, BGC20-1531, in prevention of PGE2-induced headache and the ability of prostaglandin F2α (PGF2α) to trigger headache without any vasodilatation in healthy volunteers. All studies were designed as double-blind, placebo-controlled, cross-over experiments, where PGE2/PGF2α or saline were infused over 20-25 min. In the study with EP4 receptor antagonist healthy volunteers were pre-treated with two different doses of BGC20-1531 or placebo followed by PGE2 infusion over 25 min. The headache data were collected during the whole study day, whereas the possible vascular changes were measured during the in-hospital phase of 1.5 h. 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 of migraine. The lack of efficacy of EP4 receptor antagonist suggests that a single receptor blockade is not sufficient to block PGE2 responses, hence EP2 receptor should be investigated as a potential drug target for the treatment of migraine. The absence of headache during the PGF2α infusion demonstrates that vasodilating properties are necessary for the induction of headache and migraine. PMID:23673269

  17. Effects of anti-inflammatory agents and some other drugs on prostaglandin biotransport.

    PubMed

    Bito, L Z; Salvador, E V

    1976-08-01

    The inhibitory effects of drugs on prostaglandin biotransport were studied by measuring the concentrative accumulation of 3H by rabbit choroid plexuses, segments of anterior uvea and kidney cortex slices after incubation in tissue culture medium containing 3H-prostaglandin F2 alpha. After 10 minutes of incubation in the absence of an inhibitor, the choroid plexus showed a tissue/medium 3H accumulation ratio of 14 +/- 0.7; after 30 minutes of incubation, the anterior uvea and the kidney cortex slices showed accumulation ratios of 6.4 +/- 0.5 and 5.6 +/- 0.1, respectively. The I50 values for inhibition of 3H accumulation by indomethacin were 10, 8 and 12 muM for the three tissues, respectively. Some related drugs-oxyphenbutazone, D-naproxen, l-naproxen, ibuprofen, phenylbutazone and pirprofen-were also found to be effective inhibitors of 3H accumulation (I50 for anterior uvea, 6-28 muM) whereas aspirin, dexamethasone phosphate and penicillin had an inhibitory effect only at much higher concentrations (I50 0.1-2.0 mM). Papaverine, fursemide and probenecid were approximately as effective as the anti-inflammatory organic acids (I50 0.01-0.1 mM), whereas bromcresol green was at least 10-fold more effective. Diphenhydramine and the nonacidic prostaglandin synthesis inhibitors, phenelzine and paracetamol, showed little (I50 greater than 1 mM) or no inhibitory effect. The inhibition of this transport system by some drugs, most notably nonsteroidal anti-inflammatory organic acids, and consequent alterations in the distribution and disposition of prostaglandins must be taken into account in the development of new anti-inflammatory agents and in the interpretation of the mechansim of action and side effects of such drugs. PMID:948038

  18. The Enteropathy of Prostaglandin Deficiency

    PubMed Central

    Adler, David H.; Phillips, John A.; Cogan, Joy D.; Iverson, Tina M.; Stein, Jeffrey A.; Brenner, David A.; Morrow, Jason D.; Boutaud, Olivier; Oates, John A.

    2009-01-01

    Purpose Small intestinal ulcers are frequent complications of therapy with non-steroidal anti-inflammatory drugs (NSAIDs). We present here a genetic deficiency of eicosanoid biosynthesis that illuminates the mechanism of NSAID-induced ulcers of the small intestine. Methods Eicosanoids and metabolites were measured by isotope-dilution with mass spectrometry. cDNA was obtained by reverse transcription and sequenced following amplification with RT-PCR. Results We investigated the cause of chronic recurrent small intestinal ulcers, small bowel perforations, and gastrointestinal blood loss in a 45 year old male who was not taking any cyclooxygenase inhibitor. Prostaglandin metabolites in urine were significantly depressed. Serum thromboxane B2 (TxB2) production was 4.6% of normal controls (p<0.006) and serum 12-HETE was 1.3% of controls (p<0.005). Optical platelet aggregation with simultaneous monitoring of ATP release demonstrated absent granule secretion in response to ADP and a blunted aggregation response to ADP and collagen, but normal response to arachidonic acid (AA). LTB4 biosynthesis by ionophore activated leukocytes was only 3% of controls and urinary LTE4 was undetectable. These findings suggested deficient AA release from membrane phospholipids by cytosolic phospholipase A2-α (cPLA2-α) which regulates cyclooxygenase and lipoxygenase mediated eicosanoid production by catalyzing the release of their substrate, AA. Sequencing of cPLA2-α cDNA demonstrated 2 heterozygous non-synonymous single base pair mutations: Ser111Pro (S111P) and Arg485His (R485H), as well as a known SNP: Lys651Arg (K651R). Conclusion Characterization of this cPLA2-α deficiency provides support for the importance of prostaglandins in protecting small intestinal integrity, and indicates that loss of prostaglandin biosynthesis is sufficient to produce small intestinal ulcers. PMID:19148786

  19. Pharmacological inhibition of interleukin-1 activity on T cells by hydrocortisone, cyclosporine, prostaglandins, and cyclic nucleotides.

    PubMed

    Tracey, D E; Hardee, M M; Richard, K A; Paslay, J W

    1988-01-01

    The effects of a panel of hormones and pharmacological agents on the activation of T cells by a combination of interleukin-1 and phytohemagglutinin (IL-1/PHA) was studied. Pharmacological effects on various stages of IL-1/PHA-induced interleukin-2 (IL-2) production by the cloned murine thymoma cell line LBRM-33-1A5.7 were dissected using a multi-step assay procedure. A 4-h lag phase in the kinetics of IL-2 production allowed the operational definition of an early, IL-1-dependent programming stage, followed by an IL-2-production stage of the assay. A cell-washing procedure between these stages was introduced in order to distinguish IL-1 receptor antagonists from functional IL-1/PHA antagonists. Hydrocortisone and cyclosporine were potent inhibitors (active in the nM range) of both stages of IL-2 production, suggesting that neither is an IL-1 receptor antagonist. The cyclic adenosine monophosphate (cAMP)-elevating agents prostaglandin E2, dibutyryl cAMP, and theophylline inhibited IL-2 production during the early, IL-1-dependent programming stage. By contrast, prostaglandin F2 alpha and dibutyryl cyclic guanosine monophosphate did not appreciably inhibit IL-1/PHA activity. These results are discussed in relationship to the effects of these test agents in thymocyte IL-1 assays or mitogenesis assays and the implications toward understanding the mechanisms underlying IL-1/PHA activation of T cells. PMID:3258857

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

    PubMed

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

    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. PMID:2633211

  1. Uncoordinate regulation of collagenase, stromelysin, and tissue inhibitor of metalloproteinases genes by prostaglandin E2: selective enhancement of collagenase gene expression in human dermal fibroblasts in culture.

    PubMed

    Mauviel, A; Halcin, C; Vasiloudes, P; Parks, W C; Kurkinen, M; Uitto, J

    1994-04-01

    The degradative effects of interleukin-1 (IL-1) on the extracellular matrix of connective tissue are mediated primarily by metalloproteinases and prostaglandins. Clinical observations suggest that these effects can be prevented, to some extent, by the use of non-steroidal anti-inflammatory drugs. We have examined the role of prostaglandin E2 (PGE2) in IL-1-induced gene expression by human skin fibroblasts in culture. Incubation of confluent fibroblast cultures with varying concentrations (0.01-1.0 microgram/ml) of PGE2 led to a dose-dependent elevation of collagenase mRNA steady-state levels, the promoter activity, and the secretion of the protein, whereas relatively little effect was observed on stromelysin and TIMP gene expression. Exogenous PGE2 had no additive or synergistic effect with IL-1 on collagenase gene expression. Furthermore, commonly used non-steroidal anti-inflammatory drugs (indomethacin, acetyl salicylic acid and ibuprofen), at doses which block prostaglandin synthesis in cultured fibroblasts, failed to counteract IL-1-induced collagenase and stromelysin gene expression, nor did they affect TIMP expression. Although the effects of PGE2 did not potentiate those of IL-1 on collagenase gene expression in vitro, one could speculate that massive production of PGE2 by connective tissue cells in vivo in response to inflammatory mediators such as IL-1 or tumor necrosis factor-alpha, could lead to sustained expression of collagenase in connective tissue cells after clearance of the growth factors. PMID:8014195

  2. Phospholipase C inhibitors and prostaglandins differentially regulate phosphatidylcholine synthesis in rat renal papilla. Evidence of compartmental regulation of CTP:phosphocholine cytidylyltransferase and CDP-choline:1,2-diacylglycerol cholinephosphotransferase.

    PubMed

    Fernández-Tomé, María del Carmen; Speziale, Emir H S; Sterin-Speziale, Norma B

    2002-07-11

    Phosphatidylcholine (PC) is the most abundant phospholipid in mammalian cell membranes. Several lines of evidence support that PC homeostasis is preserved by the equilibrium between PC biosynthetic enzymes and phospholipases catabolic activities. We have previously shown that papillary synthesis of PC depends on prostaglandins (PGs) that modulate biosynthetic enzymes. In papillary tissue, under bradikynin stimulus, arachidonic acid (AA) mobilization (the substrate for PG synthesis) requires a previous phospholipase C (PLC) activation. Thus, in the present work, we study the possible involvement of PLC in PC biosynthesis and its relationship with PG biosynthetic pathway on the maintenance of phospholipid renewal in papillary membranes; we also evaluated the relevance of CDP-choline pathway enzymes compartmentalization. To this end, neomycin, U-73122 and dibutiryl cyclic AMP, reported as PLC inhibitors, were used to study PC synthesis in rat renal papilla. All the PLC inhibitors assayed impaired PC synthesis. PG synthesis was also blocked by PLC inhibitors without affecting cyclooxygenase activity, indicating a metabolic connection between both pathways. However, we found that PC biosynthesis decrease in the presence of PLC inhibitors was not a consequence of PG decreased synthesis, suggesting that basal PLC activity and PGs exert their effect on different targets of PC biosynthetic pathway. The study of PC biosynthetic enzymes showed that PLC inhibitors affect CTP:phosphocholine cytidylyltransferase (CCT) activity while PGD(2) operates on CDP-choline:1,2-diacylglycerol cholinephosphotransferase (CPT), both activities associated to papillary enriched-nuclei fraction. The present results suggest that renal papillary PC synthesis is a highly regulated process under basal conditions. Such regulation might occur at least at two different levels of the CDP-choline pathway: on the one hand, PLC operates on CCT activity; on the other, while PGs regulate CPT activity. PMID

  3. Prostaglandin E2 receptor, EP3, is induced in diabetic islets and negatively regulates glucose- and hormone-stimulated insulin secretion.

    PubMed

    Kimple, Michelle E; Keller, Mark P; Rabaglia, Mary R; Pasker, Renee L; Neuman, Joshua C; Truchan, Nathan A; Brar, Harpreet K; Attie, Alan D

    2013-06-01

    BTBR mice develop severe diabetes in response to genetically induced obesity due to a failure of the β-cells to compensate for peripheral insulin resistance. In analyzing BTBR islet gene expression patterns, we observed that Pgter3, the gene for the prostaglandin E receptor 3 (EP3), was upregulated with diabetes. The EP3 receptor is stimulated by prostaglandin E2 (PGE2) and couples to G-proteins of the Gi subfamily to decrease intracellular cAMP, blunting glucose-stimulated insulin secretion (GSIS). Also upregulated were several genes involved in the synthesis of PGE2. We hypothesized that increased signaling through EP3 might be coincident with the development of diabetes and contribute to β-cell dysfunction. We confirmed that the PGE2-to-EP3 signaling pathway was active in islets from confirmed diabetic BTBR mice and human cadaveric donors, with increased EP3 expression, PGE2 production, and function of EP3 agonists and antagonists to modulate cAMP production and GSIS. We also analyzed the impact of EP3 receptor activation on signaling through the glucagon-like peptide (GLP)-1 receptor. We demonstrated that EP3 agonists antagonize GLP-1 signaling, decreasing the maximal effect that GLP-1 can elicit on cAMP production and GSIS. Taken together, our results identify EP3 as a new therapeutic target for β-cell dysfunction in T2D. PMID:23349487

  4. Prostaglandin E2 Receptor, EP3, Is Induced in Diabetic Islets and Negatively Regulates Glucose- and Hormone-Stimulated Insulin Secretion

    PubMed Central

    Kimple, Michelle E.; Keller, Mark P.; Rabaglia, Mary R.; Pasker, Renee L.; Neuman, Joshua C.; Truchan, Nathan A.; Brar, Harpreet K.; Attie, Alan D.

    2013-01-01

    BTBR mice develop severe diabetes in response to genetically induced obesity due to a failure of the β-cells to compensate for peripheral insulin resistance. In analyzing BTBR islet gene expression patterns, we observed that Pgter3, the gene for the prostaglandin E receptor 3 (EP3), was upregulated with diabetes. The EP3 receptor is stimulated by prostaglandin E2 (PGE2) and couples to G-proteins of the Gi subfamily to decrease intracellular cAMP, blunting glucose-stimulated insulin secretion (GSIS). Also upregulated were several genes involved in the synthesis of PGE2. We hypothesized that increased signaling through EP3 might be coincident with the development of diabetes and contribute to β-cell dysfunction. We confirmed that the PGE2-to-EP3 signaling pathway was active in islets from confirmed diabetic BTBR mice and human cadaveric donors, with increased EP3 expression, PGE2 production, and function of EP3 agonists and antagonists to modulate cAMP production and GSIS. We also analyzed the impact of EP3 receptor activation on signaling through the glucagon-like peptide (GLP)-1 receptor. We demonstrated that EP3 agonists antagonize GLP-1 signaling, decreasing the maximal effect that GLP-1 can elicit on cAMP production and GSIS. Taken together, our results identify EP3 as a new therapeutic target for β-cell dysfunction in T2D. PMID:23349487

  5. 15-Deoxy-{delta}{sup 12,14}-prostaglandin J{sub 2} down-regulates CXCR4 on carcinoma cells through PPAR{gamma}- and NF{kappa}B-mediated pathways

    SciTech Connect

    Richard, Cynthia Lee; Lowthers, Erica Lauren; Blay, Jonathan

    2007-10-01

    The chemokine receptor CXCR4 plays a key role in the metastasis of colorectal cancer and its growth at metastatic sites. Here, we have investigated the mechanisms by which CXCR4 on cancer cells might be regulated by eicosanoids present within the colorectal tumor microenvironment. We show that prostaglandins PGE{sub 2}, PGA{sub 2}, PGD{sub 2}, PGJ{sub 2} and 15dPGJ{sub 2} each down-regulates CXCR4 receptor expression on human colorectal carcinoma cells to differing degrees. The most potent of these were PGD{sub 2} and its metabolites PGJ{sub 2} and 15dPGJ{sub 2}. Down-regulation was most rapid with the end-product 15dPGJ{sub 2} and was accompanied by a marked reduction in CXCR4 mRNA. 15dPGJ{sub 2} is known to be a ligand for the nuclear receptor PPAR{gamma}. Down-regulation of CXCR4 was also observed with the PPAR{gamma} agonist rosiglitazone, while 15dPGJ{sub 2}-induced CXCR4 down-regulation was substantially diminished by the PPAR{gamma} antagonists GW9662 and T0070907. These data support the involvement of PPAR{gamma}. However, the 15dPGJ{sub 2} analogue CAY10410, which can act on PPAR{gamma} but which lacks the intrinsic cyclopentenone structure found in 15dPGJ{sub 2}, down-regulated CXCR4 substantially less potently than 15dPGJ{sub 2}. The cyclopentenone grouping is known to inhibit the activity of NF{kappa}B. Consistent with an additional role for NF{kappa}B, we found that the cyclopentenone prostaglandin PGA{sub 2} and cyclopentenone itself could also down-regulate CXCR4. Immunolocalization studies showed that the cellular context was sufficient to trigger a focal nuclear pattern of NF{kappa}B p50 and that 15dPGJ{sub 2} interfered with this p50 nuclear localization. These data suggest that 15dPGJ{sub 2} can down-regulate CXCR4 on cancer cells through both PPAR{gamma} and NF{kappa}B. 15dPGJ{sub 2}, present within the tumor microenvironment, may act to down-regulate CXCR4 and impact upon the overall process of tumor expansion.

  6. Gastroprotective Activities of Sennoside A and Sennoside B via the Up-Regulation of Prostaglandin E2 and the Inhibition of H+/K+-ATPase

    PubMed Central

    Hwang, In Young; Jeong, Choon Sik

    2015-01-01

    Sennoside A (erythro) and sennoside B (threo) are dianthrone glycosides and diastereomers. We investigated their abilities to prevent the gastric lesions associated with diseases, such as, gastritis and gastric ulcer. To elucidate their gastroprotective effects, the inhibitions of HCl•EtOH-induced gastritis and indomethacin-induced gastric ulcers were assessed in rats. It was observed that both sennoside A and sennoside B increased prostaglandin E2 (PGE2) levels and inhibited H+/K+-ATPase (proton pump). In a rat model, both compounds reduced gastric juice, total acidity and increased pH, indicating that proton pump inhibition reduces gastric acid secretion. Furthermore, sennoside A and B increased PGE2 in a concentration-dependent manner. In a gastric emptying and intestinal transporting rate experiment, both sennoside A and sennoside B accelerated motility. Our results thus suggest that sennoside A and sennoside B possess significant gastroprotective activities and they might be useful for the treatment of gastric disease. PMID:26336586

  7. Dissociation of bradykinin-induced prostaglandin formation from phosphatidylinositol turnover in Swiss 3T3 fibroblasts: evidence for G protein regulation of phospholipase A/sub 2/

    SciTech Connect

    Burch, R.M.; Axelrod, J.

    1987-09-01

    In Swiss 3T3 fibroblasts bradykinin stimulated inositol phosphate (InsP) formation and prostaglandin E/sub 2/ (PGE/sub 2/) synthesis. The EC/sub 50/ values for stimulation of PGE/sub 2/ synthesis and InsP formation by bradykinin were similar, 200 pM and 275 pM, respectively. Guanosine-5'-(..gamma..-thio)triphosphate stimulated PGE/sub 2/ synthesis and InsP formation, and guanosine-5'-(..beta..-thio)diphosphate inhibited both PGE/sub 2/ synthesis and InsP formation stimulated by bradykinin. Neither bradykinin-stimulated PGE/sub 2/ synthesis nor InsP formation was sensitive to pertussis toxin. Phorbol ester, dexamethasone, and cycloheximide distinguished between bradykinin-stimulated PGE/sub 2/ synthesis and InsP formation. Phorbol 12-myristate 13-acetate enhanced bradykinin-stimulated PGE/sub 2/ synthesis but inhibited bradykinin-stimulated InsP formation. Pretreatment of cells with dexamethasone for 24 hr inhibited bradykinin-stimulated PGE/sub 2/ synthesis but was without effect on bradykinin-stimulated InsP formation. Cycloheximide inhibited on bradykinin-stimulated InsP formation. When bradykinin was added to cells prelabeled with (/sup 3/H) choline, the phospholipase A/sub 2/ products lysophosphatidylcholine and glycerophosphocholine were generated. The data suggest that bradykinin receptors are coupled by GTP-binding proteins to both phospholipase C and phospholipase A/sub 2/ and that phospholipase A/sub 2/ is the enzyme that catalyzes release of arachidonate for prostaglandin synthesis.

  8. Prostaglandins and mechanisms of preterm birth.

    PubMed

    Challis, John R G; Sloboda, Deborah M; Alfaidy, Nadia; Lye, Steven J; Gibb, William; Patel, Fal A; Whittle, Wendy L; Newnham, John P

    2002-07-01

    Increased uterine contractility at term and preterm results first from activation and then stimulation of the myometrium. Activation can be provoked by mechanical stretch of the uterus, and by an endocrine pathway resulting from increased activity of the fetal hypothalamic-pituitary-adrenal axis. In sheep fetuses, increased cortisol output during pregnancy regulates expression of prostaglandin synthase type 2 (PGHS-2) in the placenta in an oestrogen-independent manner, resulting in increased concentrations of prostaglandin E2 (PGE2) in the fetal circulation. Later increases in maternal uterine expression of PGHS-2 require increases in oestrogen and lead to increased concentrations of PGF(2alpha) in the maternal circulation. Thus, regulation of PGHS-2 at term is differentially controlled in fetal (trophoblast) and maternal (uterine epithelium) tissue. This difference may reflect expression of glucocorticoid receptor but not oestrogen receptor (ER) in placental trophoblast cells. In women, cortisol also contributes to increased prostaglandin production in fetal tissues through upregulation of PGHS-2 (amnion and chorion) and downregulation of 15-OH prostaglandin dehydrogenase (PGDH; chorion trophoblasts). The effect of cortisol on expression of PGDH in the chorion reverses a tonic stimulatory effect of progesterone, potentially through a paracrine or autocrine action. In membranes, cortisol may be derived from cortisone through activity of 11beta-hydroxysteroid dehydrogenase (11beta-HSD) type 1, in addition to secretion from the maternal or fetal adrenal glands. In placenta, 11beta-HSD-2 oxidase activity predominates and expression of this enzyme is reduced with hypoxaemia and in placentae from pre-eclamptic pregnancies. In these circumstances, increased concentrations of maternal cortisol may cross into the fetal compartment, contributing to growth restriction and programming later life disease. PMID:12090913

  9. Misidentification of prostamides as prostaglandins.

    PubMed

    Glass, Michelle; Hong, Jiwon; Sato, Timothy A; Mitchell, Murray D

    2005-07-01

    Prostaglandins and endogenous cannabinoid metabolites share the same lipid backbone with differing polar head groups at exactly the position through which a large molecule is attached to provide antigenicity and thus raise antisera. Hence, we hypothesized that antisera raised against prostaglandins linked to a large molecule such as BSA at the carboxyl functional group would also recognize endogenous cannabinoid metabolites and lead to highly misleading interpretations of data. We found major cross-reactivity of commercial antisera raised to prostaglandins with endocannabinoid metabolites. Furthermore, in a well-characterized cell line (WISH) or primary amnion tissue explants, endocannabinoid treatment led to increased production of endocannabinoid metabolites as opposed to primary prostaglandins. This was apparent only after separation of products by thin-layer chromatography, because they measured as prostaglandins by radioimmunoassay. These findings have major implications for our interpretation of data in situations in which these prostaglandin-like molecules are formed, and they stress the need for chromatographic or spectrometric confirmation of prostaglandin production detected by antibody-based methods. PMID:15863842

  10. Effect of prostaglandins and cyclic adenosine 3',5'-monophosphate modulators on herpes simplex virus growth and interferon response in human cells.

    PubMed Central

    Trofatter, K F; Daniels, C A

    1980-01-01

    Mechanisms whereby prostaglandins and other cyclic adenosine 3',5'-monophosphate (cAMP) modulators might enhance the growth of herpes simplex virus (HSV) in human skin fibroblasts were explored. Prostaglandins A1, B1, E1, E2, and F2 alpha, as well as isoproterenol, imidazole, carbamylcholine, and dibutyryl cAMP had no effect on HSV growth. On the other hand, the phosphodiesterase inhibitors 1-methyl-3-isobutylxanthine and theophylline delayed the growth, suppressed the cell-to-cell spread, but inhibited neither the adsorption nor the penetration of the virus. Although none of the cAMP-elevating reagents directly enhanced HSV growth, they were found to inhibit dose dependently the antiviral action of both type I and HSV antigen-induced human interferon preparations. Furthermore, these reagents suppressed the production of HSV antigen-induced interferon by immune human mononuclear leukocytes. These data support the hypothesis that prostaglandin elaboration in vivo could contribute to exacerbations of HSV infections by compromising the host's interferon defense system. PMID:6244226

  11. Regulation of metalloproteinases and NF-kappaB activation in rabbit synovial fibroblasts via E prostaglandins and Erk: contrasting effects of nabumetone and 6MNA.

    PubMed

    Pillinger, Michael H; Dinsell, Victoria; Apsel, Beth; Tolani, Sonia N; Marjanovic, Nada; Chan, Edwin S L; Gomez, Paul; Clancy, Robert; Chang, Lih-Fan; Abramson, Steven B

    2004-07-01

    1 Nabumetone is a prodrug that is converted in vivo into 6-methoxy-2-naphthylacetic acid (6MNA), a cyclooxygenase inhibitor with anti-inflammatory properties. We tested the effects of nabumetone and 6MNA on the inflammatory responses of synovial fibroblasts (SFs). 2 Brief exposures to 6MNA (50-150 microm) had no effect on IL-1beta/TNF-alpha (each 20 ng ml(-1))-stimulated Erk activation. Longer exposures depleted prostaglandin E1 (PGE1) as much as 70%, and stimulated Erk as much as 300%. Nabumetone (150 microm) inhibited Erk activation by 60-80%. 6MNA (50-150 microm) stimulated (approximately 200%) and nabumetone (150 microm) inhibited (approximately 50%) matrix metalloproteinase (MMP)-1, but not MMP-13 secretion from SFs. 3 6MNA stimulation of MMP-1 secretion was inhibited approximately 30% by PGE1 (1 microm) and approximately 80% by the Erk pathway inhibitor UO126 (10 microm), confirming that PGE depletion and Erk activation mediate MMP-1 secretion by 6MNA. 4 Consistent with its role as an Erk inhibitor, nabumetone (150 microm) abrogated 6MNA enhancement of MMP-1 secretion. 5 UO126 (10 microm) and nabumetone (150 microm) inhibited (approximately 70 and 40%, respectively), but 6MNA (150 microm) enhanced (approximately 40%), NF-kappaB activation. 6 Our data indicate that 6MNA shares with other COX inhibitors several proinflammatory effects on synovial fibroblasts. In contrast, nabumetone demonstrates anti-inflammatory and potentially arthroprotective effects that have not been previously appreciated. PMID:15210577

  12. The ω6-fatty acid, arachidonic acid, regulates the conversion of white to brite adipocyte through a prostaglandin/calcium mediated pathway

    PubMed Central

    Pisani, Didier F.; Ghandour, Rayane A.; Beranger, Guillaume E.; Le Faouder, Pauline; Chambard, Jean-Claude; Giroud, Maude; Vegiopoulos, Alexandros; Djedaini, Mansour; Bertrand-Michel, Justine; Tauc, Michel; Herzig, Stephan; Langin, Dominique; Ailhaud, Gérard; Duranton, Christophe; Amri, Ez-Zoubir

    2014-01-01

    Objective Brite adipocytes are inducible energy-dissipating cells expressing UCP1 which appear within white adipose tissue of healthy adult individuals. Recruitment of these cells represents a potential strategy to fight obesity and associated diseases. Methods/Results Using human Multipotent Adipose-Derived Stem cells, able to convert into brite adipocytes, we show that arachidonic acid strongly inhibits brite adipocyte formation via a cyclooxygenase pathway leading to secretion of PGE2 and PGF2α. Both prostaglandins induce an oscillatory Ca++ signaling coupled to ERK pathway and trigger a decrease in UCP1 expression and in oxygen consumption without altering mitochondriogenesis. In mice fed a standard diet supplemented with ω6 arachidonic acid, PGF2α and PGE2 amounts are increased in subcutaneous white adipose tissue and associated with a decrease in the recruitment of brite adipocytes. Conclusion Our results suggest that dietary excess of ω6 polyunsaturated fatty acids present in Western diets, may also favor obesity by preventing the “browning” process to take place. PMID:25506549

  13. Plasmodium falciparum produces prostaglandins that are pyrogenic, somnogenic, and immunosuppressive substances in humans.

    PubMed

    Kilunga Kubata, B; Eguchi, N; Urade, Y; Yamashita, K; Mitamura, T; Tai, K; Hayaishi, O; Horii, T

    1998-09-21

    Plasmodium falciparum causes the most severe form of human malaria, which kills approximately 1.5-2.7 million people every year, but the molecular mechanisms underlying the clinical symptoms and the host-parasite interaction remain unclear. We show here that P. falciparum produces prostaglandins (PGs) D2, E2, and F2alpha. After incubation with 1 mM arachidonic acid (AA), cell homogenates of P. falciparum produced PGs as determined by enzyme immunoassay and gas chromatography-selected ion monitoring. PG production in the parasite homogenate was not affected by the nonsteroidal antiinflammatory drugs aspirin and indomethacin, and was partially heat resistant, whereas PG biosynthesis by mammalian cyclooxygenase was completely inhibited by these chemicals and by heat treatment. Addition of AA to the parasite cell culture markedly increased an ability of the parasite cell homogenate to produce PGs and of parasitized red blood cells to accumulate PGs in the culture medium. PGD2 and PGE2 accumulated in the culture medium at the stages of trophozoites and schizonts more actively than at the ring stage. These findings are the first evidence of the direct involvement of a malaria parasite in the generation of substances that are pyrogenic and injurious to the host defenses. We will discuss a possible contribution of the parasite-produced PGs to pathogenesis and host-parasite interaction of P. falciparum. PMID:9743538

  14. UVB light upregulates prostaglandin synthases and prostaglandin receptors in mouse keratinocytes

    SciTech Connect

    Black, Adrienne T.; Gray, Joshua P.; Shakarjian, Michael P.; Mishin, Vladimir; Laskin, Debra L.; Heck, Diane E.; Laskin, Jeffrey D.

    2008-10-01

    Prostaglandins belong to a class of cyclic lipid-derived mediators synthesized from arachidonic acid via COX-1, COX-2 and various prostaglandin synthases. Members of this family include prostaglandins such as PGE{sub 2}, PGF{sub 2{alpha}}, PGD{sub 2} and PGI{sub 2} (prostacyclin) as well as thromboxane. In the present studies we analyzed the effects of UVB on prostaglandin production and prostaglandin synthase expression in primary cultures of undifferentiated and calcium-differentiated mouse keratinocytes. Both cell types were found to constitutively synthesize PGE{sub 2}, PGD{sub 2} and the PGD{sub 2} metabolite PGJ{sub 2}. Twenty-four hours after treatment with UVB (25 mJ/cm{sup 2}), production of PGE{sub 2} and PGJ{sub 2} increased, while PGD{sub 2} production decreased. This was associated with increased expression of COX-2 mRNA and protein. UVB (2.5-25 mJ/cm{sup 2}) also caused marked increases in mRNA expression for the prostanoid synthases PGDS, mPGES-1, mPGES-2, PGFS and PGIS, as well as expression of receptors for PGE{sub 2} (EP1 and EP2), PGD{sub 2} (DP and CRTH2) and prostacyclin (IP). UVB was more effective in inducing COX-2 and DP in differentiated cells and EP1 and IP in undifferentiated cells. UVB readily activated keratinocyte PI-3-kinase (PI3K)/Akt, JNK and p38 MAP signaling pathways which are known to regulate COX-2 expression. While inhibition of PI3K suppressed UVB-induced mPGES-1 and CRTH2 expression, JNK inhibition suppressed mPGES-1, PGIS, EP2 and CRTH2, and p38 kinase inhibition only suppressed EP1 and EP2. These data indicate that UVB modulates expression of prostaglandin synthases and receptors by distinct mechanisms. Moreover, both the capacity of keratinocytes to generate prostaglandins and their ability to respond to these lipid mediators are stimulated by exposure to UVB.

  15. Nodal Promotes Functional Luteolysis via Down-Regulation of Progesterone and Prostaglandins E2 and Promotion of PGF2α Synthetic Pathways in Mare Corpus Luteum.

    PubMed

    Galvão, António; Skarzynski, Dariusz; Ferreira-Dias, Graça

    2016-02-01

    In the present work, we investigated the role of Nodal, an embryonic morphogen from the TGFβ superfamily in corpus luteum (CL) secretory activity using cells isolated from equine CL as a model. Expression pattern of Nodal and its receptors activin receptor A type IIB (ACVR2B), activin receptor-like kinase (Alk)-7, and Alk4, as well as the Nodal physiological role, demonstrate the involvement of this pathway in functional luteolysis. Nodal and its receptors were immune localized in small and large luteal cells and endothelial cells, except ACVR2B, which was not detected in the endothelium. Nodal mRNA in situ hybridization confirmed its transcription in steroidogenic and endothelial cells. Expression analysis of the aforementioned factors evidenced that Nodal and Alk7 proteins peaked at the mid-CL (P < .01), the time of luteolysis initiation, whereas Alk4 and ACVR2B proteins increased from mid- to late CL (P < .05). The Nodal treatment of luteal cells decreased progesterone and prostaglandin (PG) E2 concentrations in culture media (P < .05) as well as mRNA and protein of secretory enzymes steroidogenic acute regulatory protein, cholesterol side-chain cleavage enzyme, cytosolic PGE2 synthase, and microsomal PGE2 synthase-1 (P < .05). Conversely, PGF2α secretion and gene expression of PG-endoperoxidase synthase 2 and PGF2α synthase were increased after Nodal treatment (P < .05). Mid-CL cells cultured with PGF2α had increased Nodal protein expression (P < .05) and phosphorylated mothers against decapentaplegic-3 phosphorylation (P < .05). Finally, the supportive interaction between Nodal and PGF2α on luteolysis was shown to its greatest extent because both factors together more significantly inhibited progesterone (P < .05) and promoted PGF2α (P < .05) synthesis than Nodal or PGF2α alone. Our results neatly pinpoint the sites of action of the Nodal signaling pathway toward functional luteolysis in the mare. PMID:26653568

  16. Coronary flow regulation in patients with ischemic heart disease: release of purines and prostacyclin and the effect of inhibitors of prostaglandin formation.

    PubMed

    Edlund, A; Berglund, B; van Dorne, D; Kaijser, L; Nowak, J; Patrono, C; Sollevi, A; Wennmalm, A

    1985-06-01

    The present investigation was undertaken to study cardiac release of adenosine and prostacyclin (prostaglandin [PG] I2) in patients with ischemic heart disease (IHD), and to assess coronary vascular resistance before and after inhibition of synthesis in such patients. In 48 patients with IHD, arterial and coronary sinus blood samples were taken at rest, during atrial pacing to angina, and after pacing. Levels of purines were determined by high-performance liquid chromatography and the PGI2 metabolite 6-keto-PGF1 alpha was measured with radioimmunoassay. Coronary sinus blood flow was determined with retrograde continuous thermodilution before and after oral administration of indomethacin, aspirin, naproxen, or ibuprofen. Atrial pacing induced myocardial ischemia, as evidenced by typical chest pain and arrested lactate extraction. Adenosine was extracted at rest, but during ischemia there was a significant release of its metabolite hypoxanthine, indicating increased myocardial breakdown of high-energy adenine nucleotides. Arterial and coronary sinus concentrations of 6-keto-PGF1 alpha were low and no significant differences between them were found. After administration of the PG-synthesis inhibitor indomethacin, coronary vascular resistance was elevated, as was the cardiac oxygen extraction. The three other PG-synthesis inhibitors (aspirin, naproxen, and ibuprofen) did not, however, induce any change in coronary vascular resistance or in the cardiac extraction of oxygen. On the basis of these data we suggest that in patients with IHD cardiac ischemia results in increased myocardial production and release of purines, cardiac ischemia does not elicit any detectable increase in coronary production of prostacyclin, and the increased coronary resistance induced by indomethacin does not reflect the involvement of locally formed PG in the maintenance of coronary flow, but is rather a direct effect of the drug. PMID:3888437

  17. Calcium/calmodulin-dependent protein kinase II regulates cyclooxygenase-2 expression and prostaglandin E2 production by activating cAMP-response element-binding protein in rat peritoneal macrophages

    PubMed Central

    Zhou, Xueyuan; Li, Junying; Yang, Wenxiu

    2014-01-01

    Prostaglandin E2 (PGE2) is an important inducer of inflammation, which is also closely linked to the progress of tumours. In macrophages, PGE2 production is regulated by arachidonic acid release and cyclooxygenase-2 (COX-2) expression. In the present study, we found that COX-2 expression can be achieved by activating Ca2+/Calmodulin (CaM)-dependent protein kinase II (CaMKII) and cAMP-response element-binding protein (CREB) in rat peritoneal macrophages. Our results indicated that lipopolysaccharide and PMA could elicit the transient increase of the concentration of intracellular free calcium ions ([Ca2+]i), which induced activation of CaMKs with the presence of CaM. The subtype of CaMKs, CaMKII, then triggered the activation of CREB, which elevated COX-2 expression and PGE2 production in a chronological order. These results suggested that Ca2+/CaM-dependent CaMKII plays an important role in mediating COX-2 expression and PGE2 production by activating CREB in macrophages. The study also provides more useful information to clarify the mechanism of calcium regulation of PGE2 production, which plays an essential role in inflammation and cancers. PMID:24773364

  18. Prostaglandins, bioassay and inflammation

    PubMed Central

    Flower, R J

    2006-01-01

    The formation of the British Pharmacological Society coincided almost exactly with a series of ground-breaking studies that ushered in an entirely new field of research – that of lipid mediator pharmacology. For many years following their chemical characterisation, lipids were considered only to be of dietary or structural importance. From the 1930s, all this changed – slowly at first and then more dramatically in the 1970s and 1980s with the emergence of the prostaglandins (PGs), the first intercellular mediators to be clearly derived from lipids, in a dynamic on-demand system. The PGs exhibit a wide range of biological activities that are still being evaluated and their properties underlie the action of one of the world's all-time favourite medicines, aspirin, as well as its more modern congeners. This paper traces the development of the PG field, with particular emphasis on the skilful utilisation of the twin techniques of bioassay and analytical chemistry by U.K. and Swedish scientists, and the intellectual interplay between them that led to the award of a joint Nobel Prize to the principal researchers in the PG field, half a century after the first discovery of these astonishingly versatile mediators. PMID:16402103

  19. Coordinate Functional Regulation between Microsomal Prostaglandin E Synthase-1 (mPGES-1) and Peroxisome Proliferator-activated Receptor γ (PPARγ) in the Conversion of White-to-brown Adipocytes*

    PubMed Central

    García-Alonso, Verónica; López-Vicario, Cristina; Titos, Esther; Morán-Salvador, Eva; González-Périz, Ana; Rius, Bibiana; Párrizas, Marcelina; Werz, Oliver; Arroyo, Vicente; Clària, Joan

    2013-01-01

    Peroxisome proliferator-activated receptor γ (PPARγ) is a ligand-activated nuclear receptor and a master regulator of adipogenesis. Microsomal prostaglandin E (PGE) synthase-1 (mPGES-1) is an inducible enzyme that couples with cyclooxygenase-2 for the biosynthesis of PGE2. In this study we demonstrate the existence of a coordinate functional interaction between PPARγ and mPGES-1 in controlling the process of pre-adipocyte differentiation in white adipose tissue (WAT). Adipocyte-specific PPARγ knock-out mice carrying an aP2 promoter-driven Cre recombinase transgene showed a blunted response to the adipogenic effects of a high fat diet. Pre-adipocytes from these knock-out mice showed loss of PPARγ and were resistant to rosiglitazone-induced WAT differentiation. In parallel, WAT from these mice showed increased expression of uncoupling protein 1, a mitochondrial enzyme that dissipates chemical energy as heat. Adipose tissue from mice lacking PPARγ also showed mPGES-1 up-regulation and increased PGE2 levels. In turn, PGE2 suppressed PPARγ expression and blocked rosiglitazone-induced pre-adipocyte differentiation toward white adipocytes while directly elevating uncoupling protein 1 expression and pre-adipocyte differentiation into mature beige/brite adipocytes. Consistently, pharmacological mPGES-1 inhibition directed pre-adipocyte differentiation toward white adipocytes while suppressing differentiation into beige/brite adipocytes. This browning effect was reproduced in knockdown experiments using a siRNA directed against mPGES-1. The effects of PGE2 on pre-adipocyte differentiation were not seen in mice lacking PPARγ in adipose tissue and were not mirrored by other eicosanoids (i.e. leukotriene B4). Taken together, these findings identify PGE2 as a key regulator of white-to-brown adipogenesis and suggest the existence of a coordinate regulation of adipogenesis between PPARγ and mPGES-1. PMID:23943621

  20. Prostaglandin D2 induces the production of human beta-defensin-3 in human keratinocytes.

    PubMed

    Kanda, Naoko; Ishikawa, Takeko; Watanabe, Shinichi

    2010-04-01

    The antimicrobial peptide human beta-defensin-3 (hBD-3) is produced by epidermal keratinocytes and protects the skin from infections. This peptide induces the release of a lipid mediator, prostaglandin D(2) from dermal mast cells. Prostaglandin D(2) binds to cell-surface G protein-coupled receptors, D prostanoid receptor, and chemoattractant receptor-homologous molecule expressed on T helper cell type 2 (CRTH2). Both receptors are detected on epidermal keratinocytes. It is reported that prostaglandin D(2) is involved in cutaneous allergy, however, its role in antimicrobial defense is unknown. We examined the in vitro effects of prostaglandin D(2) on hBD-3 production in normal human keratinocytes. Prostaglandin D(2) enhanced hBD-3 secretion and mRNA expression in human keratinocytes. Prostaglandin D(2)-induced hBD-3 production was suppressed by the CRTH2 antagonist ramatroban and by antisense oligonucleotides against c-Jun and c-Fos, components of a transcription factor, activator protein-1 (AP-1). Prostaglandin D(2) enhanced the transcriptional activity and DNA binding of AP-1, expression, phosphorylation, and DNA binding of c-Fos proteins in keratinocytes. Prostaglandin D(2)-induced hBD-3 production, AP-1 activity, and c-Fos expression and phosphorylation were suppressed by U0126, PP2, and pertussis toxin, which are inhibitors of mitogen-activated protein kinase kinase (MEK), src, and G(i) proteins, respectively. The phosphorylation of extracellular signal-regulated kinase (ERK), downstream kinase of MEK, was induced by prostaglandin D(2), and suppressed by ramatroban, pertussis toxin, PP2, and U0126. These results suggest that prostaglandin D(2) induces hBD-3 production in human keratinocytes by activating AP-1 through the expression and phosphorylation of c-Fos via the CRTH2/G(i)/src/MEK/ERK pathway. Prostaglandin D(2) may promote cutaneous antimicrobial activity via hBD-3. PMID:19925780

  1. Prostaglandin E3 metabolism and cancer

    PubMed Central

    Yang, Peiying; Jiang, Yan; Fischer, Susan M.

    2015-01-01

    The anticancer activity of n-3 fatty acids, especially those derived from fish, such as eicosapentaenoic acid (EPA) and docosahexaenoic acid) (DHA), has been studied for centuries. While there is a growing body of evidence that EPA and DHA may influence cancer initiation and development through targeting multiple events of tumor development, the underlying mechanisms responsible for these activities are still not fully understood. A number of studies have suggested that the anticancer activities of EPA and DHA are associated with their effects on eicosanoid metabolism by which they inhibit prostaglandin E2 (PGE2) production. In contrast to DHA, EPA can function as a substrate for cyclooxygenases (COXs) to synthesize unique 3-series prostaglandin compounds, especially PGE3. With advance technology in mass spectrometry, there is renewed interest in studying the role of PGE3 in EPA elicited anti-proliferative activity in various cancers, with some promising results. Here, we summarize the regulation of PGE3 synthesis in cancer cells and its role in EPA elicited anticancer activity. The development of PGE3 and its metabolites as potential biomarkers for future clinical evaluation of EPA and fish oil in cancer care is discussed. PMID:24657656

  2. Regulation of Activator Protein-1 by 8-iso-Prostaglandin E{sub 2} in a Thromboxane A{sub 2} Receptor-Dependent and -Independent Manner

    SciTech Connect

    Weber, Thomas J.; Markillie, Lye MENG.

    2003-05-01

    The thromboxane A{sub 2} (TXA{sub 2}) receptor (TP) is represented by two alternatively spliced forms, termed the platelet/placental (TP-P) and endothelial (TP-E) type receptors. Experimental evidence suggests that TP isoforms may be regulated by novel ligands termed the isoprostanes, which paradoxically act as TP agonists in smooth muscle and TP antagonists in platelet preparations. Here we have investigated whether prototypical isoprostanes (8-iso-PG{sub 2{sub {alpha}}} and 8-iso-PGE{sub 2}) regulate the activity of TP isoforms expressed in Chinese Hamster Ovary (CHO) cells using activator protein-1 (AP-1)-luciferase activity as a reporter. AP-1-luciferase activity was increased by a TP agonist (U46619) in CHO cells transfected with the human TP-P and TP-E receptors and this response was fully inhibited by TP antagonists (ISAP, SQ29,548). AP-1-luciferase activity was potently (nM) increased by 8-iso-PGE2 in CHO TP-P and TP-E cells, and this response was partially inhibited by cotreatment of cells with TP antagonists, while 8-iso-PGF{sub 2{sub {alpha}}} was without effect. Cyclooxygenase inhibitors did not abolish 8-iso-PGE{sub 2} mediated AP-1-luciferase activity, indicating that this response is not dependent on de novo TXA2 biosynthesis. Interestingly, 8-iso-PGE{sub 2}-mediated AP-1-luciferase activity was near maximal in naive cells between 1-10 nM concentrations, and this response was not inhibited by TP antagonist or reproduced by agonists for TP or EP1/EP3 receptors. These observations (1) support a role for novel ligands in the regulation of TP-dependent signaling, (2) indicate that TP-P and TP-E couple to AP-1, (3) provide further evidence that isoprostanes function as TP agonists in a cell-type specific fashion, and (4) indicate that additional targets regulated by 8-iso-PGE{sub 2} couple to AP-1.

  3. Prostaglandin EP2 receptor signaling protects human trabecular meshwork cells from apoptosis induced by ER stress through down-regulation of p53.

    PubMed

    Kalouche, Georges; Boucher, Céline; Coste, Annick; Debussche, Laurent; Orsini, Cécile; Baudouin, Christophe; Debeir, Thomas; Vigé, Xavier; Rostène, William

    2016-09-01

    E-prostanoid receptor subtype 2 (EP2) agonists are currently under clinical development as hypotensive agents for the treatment of ocular hypertension. However, the effects of EP2 receptor agonists on trabecular meshwork (TM) alterations leading to primary open-angle glaucoma (POAG) are still unknown. Here, we evaluated whether EP2 receptor activation exhibits protective functions on TM cell death induced by endoplasmic reticulum (ER) stress. We show that the EP2 receptor agonist butaprost protects TM cell death mediated by the ER stress inducer tunicamycin through a cyclic AMP (cAMP)-dependent mechanism, but independent of the classical cAMP sensors, protein kinase A and exchange proteins activated by cAMP. The ER stress-induced intrinsic apoptosis inhibited by the EP2 receptor agonist was correlated with a decreased accumulation of the cellular stress sensor p53. In addition, p53 down-regulation was associated with inhibition of its transcriptional activity, which led to decreased expression of the pro-apoptotic p53-upregulated modulator of apoptosis (PUMA). The stabilization of p53 by nutlin-3a abolished butaprost-mediated cell death protection. In conclusion, we showed that EP2 receptor activation protects against ER stress-dependent mitochondrial apoptosis through down-regulation of p53. The specific inhibition of this pathway could reduce TM alterations observed in POAG patients. PMID:27321910

  4. Oxidized low-density lipoprotein-induced periodontal inflammation is associated with the up-regulation of cyclooxygenase-2 and microsomal prostaglandin synthase 1 in human gingival epithelial cells

    SciTech Connect

    Nagahama, Yu; Obama, Takashi; Usui, Michihiko; Kanazawa, Yukari; Iwamoto, Sanju; Suzuki, Kazushige; Miyazaki, Akira; Yamaguchi, Tomohiro; Yamamoto, Matsuo; Itabe, Hiroyuki

    2011-10-07

    Highlights: {yields} OxLDL-induced responses in human gingival epithelial cells were studied. {yields} OxLDL enhanced the production of IL-8, IL-1{beta} and PGE{sub 2} in Ca9-22 cells. {yields} An NF-{kappa}B inhibitor suppressed the expression of COX-2 and mPGES1 induced by oxLDL. {yields} Unlike the case in macrophages, oxLDL did not increase the CD36 level. -- Abstract: Periodontitis is characterized by chronic gingival tissue inflammation, and inflammatory mediators such as IL-8 and prostaglandin E{sub 2} (PGE{sub 2}) are associated with disease progression. Previously we showed that oxidatively modified low-density lipoprotein (oxLDL) was present in gingival crevicular fluid. In this study, the role of oxLDL in the gingival epithelial cell inflammatory response was further investigated using Ca9-22 cells and primary human oral keratinocytes (HOK). Treatment of Ca9-22 cells and HOK with oxLDL induced an up-regulation of IL-8 and the PGE{sub 2}-producing enzymes, cyclooxygenase-2 and microsomal PGE{sub 2} synthase-1. These responses induced by oxLDL were significantly suppressed by a nuclear factor-kappa B (NF-{kappa}B) inhibitor. However, unlike the result in macrophages, oxLDL did not lead to an increase in CD36 expression in these two cells. These results suggest that oxLDL elicits gingival epithelial cell inflammatory responses through an activation of the NF-{kappa}B pathway. These data suggest a mechanistic link between periodontal disease and lipid metabolism-related disorders, including atherosclerosis.

  5. Intranasal curcumin ameliorates airway inflammation and obstruction by regulating MAPKinase activation (p38, Erk and JNK) and prostaglandin D2 release in murine model of asthma.

    PubMed

    Subhashini; Chauhan, Preeti S; Dash, D; Paul, B N; Singh, Rashmi

    2016-02-01

    Asthma, a multifactorial, chronic inflammatory disease encompasses multiple complex pathways releasing number of mediators by activated mast cells, eosinophils and T lymphocytes, leading to its severity. Presently available medications are associated with certain limitations, and hence, it is imperative to search for anti-inflammatory drug preferably targeting signaling cascades involved in inflammation thereby suppressing inflammatory mediators without any side effect. Curcumin, an anti-inflammatory molecule with potent anti-asthmatic potential has been found to suppress asthmatic features by inhibiting airway inflammation and bronchoconstriction if administered through nasal route. The present study provides new insight towards anti-asthmatic potential of intranasal curcumin at lower doses (2.5 and 5.0mg/kg) in Balb/c mice sensitized and challenged with ovalbumin (OVA) which is effective in inhibiting airway inflammation. These investigations suggest that intranasal curcumin (2.5 and 5.0mg/kg) regulates airway inflammation and airway obstruction mainly by modulating cytokine levels (IL-4, 5, IFN-ƴ and TNF-α) and sPLA2 activity thereby inhibiting PGD2 release and COX-2 expression. Further, the suppression of p38 MAPK, ERK 42/44 and JNK54/56 activation elucidate the mechanism behind the inhibitory role of intranasal curcumin in asthma progression. Thus, curcumin could be better alternative for the development of nasal formulations and inhalers in near future. PMID:26761722

  6. Prostaglandin dehydrogenase and the initiation of labor.

    PubMed

    Challis, J R; Patel, F A; Pomini, F

    1999-01-01

    In summary, these studies have suggested that prostaglandin dehydrogenase may have a central role to play in the mechanisms which determine biologically active prostaglandin concentrations within human fetal membranes and placenta at the time of labor, at term or preterm. Moreover, our studies indicate that the regulation of PGDH may by multifactorial (figure 3). In certain regions of the membranes, we suggest that PGDH expression may be influenced by levels of anti-inflammatory and pro-inflammatory cytokines. In other regions of the membranes, we suggest that PGDH may be regulated at a transcriptional level by competing activities of progesterone and cortisol. The action of progesterone could be effected through systemically-derived steroid, or by locally synthesized steroid, acting in a paracrine and/or autocrine fashion. The effects of cortisol in placenta must be due to glucocorticoid derived from the maternal or fetal compartment, since the placenta lacks the hydroxylases required for endogenous cortisol production. However, metabolism of cortisol by 11 beta-HSD-2 reduces the potency of this glucocorticoid in placental tissue. In chorion however, cortisol may be formed locally, from cortisone, in addition to its being derived from the maternal circulation and/or from the amniotic fluid. Our current studies do not allow us to delineate whether the effects of progesterone and cortisol on PGDH are exerted through the glucocorticoid receptor (GR) or progesterone receptor (PR) or both. It is possible that through pregnancy, PGDH activity is maintained by progesterone acting either through low levels of PR in membranes, or, more likely, acting through GR. At term, elevated levels of cortisol compete with and displace progesterone from GR, resulting in inhibition of PGDH transcription and activity. In this way, local withdrawal of progesterone action would be effected within human intrauterine tissues, without requiring changes in systemic, circulating progesterone

  7. Ovarian steroid regulation of endometrial phospholipase A2 isoforms in horses.

    PubMed

    Ababneh, M M; Troedsson, M H T

    2013-04-01

    Real-time PCR was used to investigate the role of progesterone (P4) and oestradiol (E2) in regulation of endometrial cytosolic, secretory and calcium-independent phospholipase A2 (PLA2G4A, PLA2G2A and PLA2G6, respectively) gene expression. Ovariectomized mares underwent 6 days of E2 pre-treatment followed by 14 days of P4 supplementation. At the start of P4 treatment (Day 1), mares were assigned in a 2 × 2 factorial design to receive either E2 or vehicle starting on Day 11 and endometrial biopsy collection on either Day 14 when P4 concentrations remained high (>4 ng/ml) or Day 16 when P4 concentrations had declined (0.5-2 ng/ml). Additional biopsies were collected from ovariectomized mares on Day 8, which served as control. Blood samples were collected for P4 determination. PLA2G4A expression was higher (p < 0.05) on Day 14 compared with Day 8. In contrast, PLA2G2A did not change significantly (p < 0.12). PLA2G4A and PLA2G2A gene expression increased (p < 0.05), as P4 concentration dropped, on Day 16. In contrast, PLA2G6 gene expression did not show differences between days. Treatment with oestradiol did not increase PLA2 isoforms expression when compared to treatment with the vehicle. PLA2G4A and PLA2G2A were positively correlated with each other and negatively correlated with P4 concentrations. In conclusion, P4 withdrawal upregulated PLA2G4A and PLA2G2A gene expression, and this was not affected by E2. PLA2G4A and PLA2G2A but not PLA2G6 gene expression may be involved in controlling prostaglandin F2 alpha synthesis and luteolysis. PMID:22882596

  8. A Heterogeneous Mixture of F-Series Prostaglandins Promotes Sperm Guidance in the Caenorhabditis elegans Reproductive Tract

    PubMed Central

    Hoang, Hieu D.; Prasain, Jeevan K.; Dorand, Dixon; Miller, Michael A.

    2013-01-01

    The mechanisms that guide motile sperm through the female reproductive tract to oocytes are not well understood. We have shown that Caenorhabditis elegans oocytes synthesize sperm guiding F-series prostaglandins from polyunsaturated fatty acid (PUFA) precursors provided in yolk lipoprotein complexes. Here we use genetics and electrospray ionization tandem mass spectrometry to partially delineate F-series prostaglandin metabolism pathways. We show that omega-6 and omega-3 PUFAs, including arachidonic and eicosapentaenoic acids, are converted into more than 10 structurally related F-series prostaglandins, which function collectively and largely redundantly to promote sperm guidance. Disruption of omega-3 PUFA synthesis triggers compensatory up-regulation of prostaglandins derived from omega-6 PUFAs. C. elegans F-series prostaglandin synthesis involves biochemical mechanisms distinct from those in mammalian cyclooxygenase-dependent pathways, yet PGF2α stereoisomers are still synthesized. A comparison of F-series prostaglandins in C. elegans and mouse tissues reveals shared features. Finally, we show that a conserved cytochrome P450 enzyme, whose human homolog is implicated in Bietti's Crystalline Dystrophy, negatively regulates prostaglandin synthesis. These results support the model that multiple cyclooxygenase-independent prostaglandins function together to promote sperm motility important for fertilization. This cyclooxygenase-independent pathway for F-series synthesis may be conserved. PMID:23382703

  9. Lipopolysaccharide induces macrophage migration via prostaglandin D(2) and prostaglandin E(2).

    PubMed

    Tajima, Tsuyoshi; Murata, Takahisa; Aritake, Kosuke; Urade, Yoshihiro; Hirai, Hiroyuki; Nakamura, Masataka; Ozaki, Hiroshi; Hori, Masatoshi

    2008-08-01

    Lipopolysaccharide (LPS) produces prostaglandins (PGs) concomitant to eliciting macrophage migration. We evaluated the role of PGs in initiating the migration of macrophages, especially focusing on PGD(2) and PGE(2). In RAW264.7 macrophages, cyclooxygenase (COX)-2 inhibitor, CAY10404 [3-(4-methylsulphonylphenyl)-4-phenyl-5-trifluoromethylisoxazole], completely inhibited LPS-mediated migration at 4 h (early phase) but only partially inhibited the migration at 8 h (late phase), suggesting the presence of PG-dependent and -independent pathways. In the early phase, LPS up-regulated mRNA expressions of COX-2, hematopoietic PGD synthase (H-PGDS), and microsomal-PGE synthase 1, increasing PGD(2) and PGE(2) substantially. The chemoattractant receptor-homologous molecule expressed on Th2 lymphocytes (CRTH2) agonist, DK-PGD(2) (13-14-dihydro-15-keto-PGD(2)), and the EP4 agonist, ONO-AE1-329 (16-{3-methoxymethyl}phenyl-omega-tetranor-3,7-dithia-prostaglandin E(1)), but not selective agonists of D prostanoid receptor, E prostanoid receptor (EP) 2, or EP3, stimulated random migration (chemokinesis). In peritoneal macrophages from CRTH2-deficient and H-PGDS-deficient mice, LPS-mediated migration was significantly inhibited at either early or late phases of the migration. The H-PGDS inhibitor, HQL-79 [4-(diphenylmethoxy)-1-[3-(1H-tetrazol-5-yl)propyl-piperidine

  10. Suppression of naloxone-precipitated withdrawal jumps in morphine-dependent mice by stimulation of prostaglandin EP3 receptor.

    PubMed Central

    Nakagawa, T.; Minami, M.; Katsumata, S.; Ienaga, Y.; Satoh, M.

    1995-01-01

    , 10 fg-100 ng/mouse), butaprost (an EP2-receptor agonist, 10 fg-100 ng/mouse) or prostaglandin F2 alpha (a FP-receptor agonist, 10 fg-100 ng/mouse) 30 min before naloxone (10 mg kg-1, i.p.) did not significantly change the number of jumps precipitated by naloxone. 5. These results indicate that the prostaglandin-synthesis pathway is, at least in part, involved in the inhibitory effect of IL-1 beta on naloxone-precipitated withdrawal jumps in morphine-dependent mice, and that the prostaglandin synthesized in the brain suppresses the morphine withdrawal jumping behaviour via the EP3-receptor, but not via the EP1-, EP2-, IP- or FP-receptor. PMID:8590986

  11. Effect of cardiorespiratory fitness on vascular regulation and oxidative stress in postmenopausal women.

    PubMed

    Pialoux, Vincent; Brown, Allison D; Leigh, Richard; Friedenreich, Christine M; Poulin, Marc J

    2009-11-01

    Increasing evidence exists suggesting an important role for oxidative stress in the pathogenesis and progression of hypertension in women via a decrease of NO production after menopause. Regular physical training has been shown to upregulate antioxidant enzymatic systems, which may slow down the usual increase of oxidative stress in postmenopausal women. The aims of this study were to determine the impact of fitness status on enzymatic antioxidant efficiency, oxidative stress, and NO production and to determine the associations among oxidative stress, enzymatic antioxidant and NO production, mean arterial blood pressure (MABP), and cerebrovascular conductance (CVC) in postmenopausal women (n=40; 50 to 90 years old). Physical fitness, physical activity, resting MABP, and CVC were measured. End product of NO, lipid peroxidation (malondialdehyde and 8-iso-prostaglandin F2alpha), DNA oxidation (8-hydroxy-2'-deoxyguanosine), protein nitration (nitrotyrosine), antioxidant glutathione peroxidase, and catalase activities were measured in plasma. We identified significant negative associations between oxidative stress and indices of physical fitness (malondialdehyde: r=-0.33, P<0.05; 8-iso-prostaglandin F2alpha: r=-0.39, P<0.05; 8-hydroxy-2'-deoxyguanosine: r=-0.35, P<0.05) and physical activity (malondialdehyde: r=-0.30, P<0.05; 8-iso-prostaglandin F2alpha: r=-0.41, P<0.01; 8-hydroxy-2'-deoxyguanosine: r=-0.39, P<0.05). Conversely, glutathione peroxidase was positively correlated with fitness level (r=0.55; P<0.01). Finally, MABP and CVC were significantly associated with 8-hydroxy-2'-deoxyguanosine (MABP: r=0.36, P<0.05; CVC: r=-0.36, P<0.05), nitrotyrosine (MABP: r=0.39, P<0.05; CVC: r=-0.32, P<0.05), and the end product of NO (MABP: r=-0.57, P<0.01; CVC: r=0.44, P<0.01). These findings demonstrate that, after menopause, fitness level and regular physical activity mediate against oxidative stress by maintaining antioxidant enzyme efficiency. Furthermore, these results

  12. Effects of prostaglandins and prostaglandin synthetase inhibitors on acutely obstructed kidneys in the dog.

    PubMed

    Zwergel, U; Zwergel, T; Ziegler, M

    1991-01-01

    An intact canine model was developed to study the effects of prostaglandins (PG) and prostaglandin synthetase inhibitors on acutely obstructed kidneys. Totally implanted nephrostomy tubes were placed to measure renal pelvic pressure. Complete ureteral obstruction was obtained with a Fogarty balloon catheter inflated in the distal ureter; by this method renal pelvic pressure reached 40-50 mm Hg. Renal pelvic pressure was reduced after intravenous indomethacin and dipyrone administration, whereas blood pressure showed no major changes. Exogenous prostaglandins had both immediate and contrary effects: PGE2 caused a significant decrease, whereas PGF2 alpha caused a significant increase in renal pelvic and blood pressure. The reduced rise in renal pelvic pressure appears to be the main reason for the analgesic effects of prostaglandin synthetase inhibitors. The efficiency of these drugs in the treatment of renal colic is supported by this study, that of prostaglandins cannot be proved. PMID:1792708

  13. Prostaglandins as mediators of acidification in the urinary bladder of Bufo marinus

    SciTech Connect

    Frazier, L.W.; Yorio, T. )

    1990-05-01

    Experiments were performed to determine whether prostaglandins (PG) play a role in H+ and NH4+ excretion in the urinary bladder of Bufo marinus. Ten paired hemibladders from normal toads were mounted in chambers. One was control and the other hemibladder received PGE2 in the serosal medium (10(-5) M). H+ excretion was measured by change in pH in the mucosal fluid and reported in units of nmol (100 mg tissue)-1 (min)-1. NH4+ excretion was measured colorimetrically and reported in the same units. The control group H+ excretion was 8.4 +/- 1.67, while the experimental group was 16.3 +/- 2.64 (P less than 0.01). The NH4+ excretion in the experimental and control group was not significantly different. Bladders from toads in a 48-hr NH4+Cl acidosis (metabolic) did not demonstrate this response to PGE2 (P greater than 0.30). Toads were put in metabolic acidosis by gavaging with 10 ml of 120 mM NH4+Cl 3 x day for 2 days. In another experiment, we measured levels of PG in bladders from control (N) and animals placed in metabolic acidosis (MA). Bladders were removed from the respective toad, homogenized, extracted, and PG separated using high-pressure liquid chromatography and quantified against PG standards. The results are reported in ng (mg tissue)-1. PGE2 fraction in N was 1.09 +/- 0.14 and in MA was 3.21 +/- 0.63 (P less than 0.01). PGF1 alpha, F2 alpha and I2 were not significantly different in N and MA toads. Bladders were also removed from N and MA toads, and incubated in Ringer's solution containing (3H)arachidonic acid (0.2 microCi/ml) at 25 degrees C for 2 hr. Bladders were then extracted for PG and the extracts separated by thin layer chromatography. PG were identified using standards and autoradiography, scraped from plates, and counted in a scintillation detector. The results are reported in cpm/mg tissue x hr +/- SEM.

  14. Bacterial lipopolysaccharide induces an endocrine switch from prostaglandin F2α to prostaglandin E2 in bovine endometrium

    PubMed Central

    Herath, Shan; Lilly, Sonia T.; Fischer, Deborah P.; Williams, Erin J.; Dobson, Hilary; Bryant, Clare E.; Sheldon, I. Martin

    2009-01-01

    Escherichia coli infection of the endometrium causes uterine disease after parturition and is associated with prolonged luteal phases of the ovarian cycle in cattle. Termination of the luteal phase is initiated by prostaglandin F2α (PGF) from oxytocin-stimulated endometrial epithelial cells. Compared with normal animals, the peripheral plasma of animals with E. coli infection of the endometrium had higher concentrations of lipopolysaccharide (LPS) and prostaglandin E2 (PGE), but not PGF. Endometrial explants accumulated predominantly PGE in the culture medium in response to LPS and this effect was not reversed by oxytocin. Endometrial cells expressed the TLR4/CD14/MD-2 receptor complex necessary to detect LPS. Epithelial and stromal cells treated with LPS had higher steady-state media concentrations of PGE rather than PGF. Arachadonic acid is liberated from cell membranes by phospholipase 2 (PLA2) enzymes and converted to prostaglandins by synthase enzymes. Treatment of epithelial and stromal cells with LPS did not change the levels of PGE or PGF synthase enzymes. However, LPS stimulated increased levels of PLA2 group VI but not PLA2 group IV C immunoreactive protein in epithelial cells. Endometrial cells expressed the EP2 and EP4 receptors necessary to respond to PGE, which regulates inflammation as well as being luteotropic. In conclusion, LPS detection by endometrial cells stimulated the accumulation of PGE rather than PGF, providing a mechanism to explain prolonged luteal phases in animals with uterine disease, and this PGE may also be important for regulating inflammatory responses in the endometrium. PMID:19056817

  15. Synthesis of prostaglandin E2, thromboxane B2 and prostaglandin catabolism in gastritis and gastric ulcer.

    PubMed Central

    Hawkey, C J

    1986-01-01

    Because endogenous prostaglandins may protect the gastric mucosa a study was conducted to determine factors influencing the synthesis of immunoreactive prostaglandin (iPG) E2 and thromboxane (iTx) B2 as measured by radioimmunoassay and prostaglandin catabolism measured radiometrically, in human gastric mucosa. Gastric mucosa was obtained at endoscopy. Synthesis of iPE2 and iTxB2 was inhibited in vitro by indomethacin; iTxB2 synthesis was also selectively inhibited by the thromboxane synthesis inhibitor dazmegrel. Prostaglandin catabolism was inhibited by carbenoxolone. Multivariate analysis showed that synthesis of iPGE2 from endogenous precursor during homogenisation was decreased in patients on non-steroidal anti-inflammatory drugs. Mucosal inflammation was associated with significantly increased synthesis of iPGE2 and decreased prostaglandin catabolism. There were no differences between the mucosa of patients with or without gastric ulcers, nor between the ulcer rim and mucosa 5 cm away. Age, sex, smoking history and ingestion of antisecretory drugs appeared to exert no influence. In this study gastritis was the major influence on prostaglandin synthesis. It seems unlikely that prostaglandin deficiency is a strong predisposing factor for gastric ulceration. PMID:3468053

  16. Effects of pressure overload and insulin on protein turnover in the perfused rat heart. Prostaglandins are not involved although their synthesis is stimulated by insulin.

    PubMed Central

    Smith, D M; Sugden, P H

    1987-01-01

    A modified anterogradely perfused rat heart preparation is described in which all the cardiac output passes through the coronary circulation. Such a preparation develops hypertensive aortic pressures. Hypertensive aortic pressures or insulin stimulate the rate of cardiac protein synthesis and inhibit the rate of protein degradation. Aortic pressure and insulin may be important in the regulation of cardiac nitrogen balance in vivo. By abolishing cardiac prostaglandin synthesis with 4-biphenylacetate, we were able to investigate the possible involvement of prostaglandins in the modulation of protein turnover by pressure overload or insulin. There was no evidence of any involvement. However, insulin stimulated and cycloheximide inhibited cardiac prostaglandin synthesis. These findings are consonant with an enzyme involved in prostaglandin synthesis being short-lived and prostaglandin synthesis being rapidly influenced by activators and inhibitors of protein synthesis and degradation. PMID:3307762

  17. [Prostaglandins in gynecology and obstetrics].

    PubMed

    Klausch, B; Kyank, H

    1972-06-01

    A review of early research (up through 1970) on prostaglandins (PGs) is presented. Their chemical structure and classification based on their ring-structure is detailed as well as various analytic methods of mammalian tissues and body fluids. For clinical use PGE1 and 2, PGF2alpha and PGA1 are the most significant ones because of their properties. PGs have many physiological activities encompassing many organ systems. Their pharmacological actions include: 1) stimulation of nonvascular smooth muscle; 2) peripheral vasodilation (excluding PGFs which cause vasoconstriction); 3) inhibition of lipolysis; 4) inhibition of platelet aggregation; 5) inhibition of gastric peristalsis and gastric juice secretion; 6) bronchodilation; and 7) inhibition of spontaneous CNS activity. The level of PGEs in semen is closely related to the degree of fertility; normally fertile men have 55 mcg PGE/ml and never less than 11 mcg/ml. Current studies are under way on the effect of PGE in artificial insemination of sperm of subfertile men. PGF2alpha and PGE2 stimulate menstruation and uterine contraction; other PGs inhibit uterine contraction. PGs from semen have a role in sperm transport and possibly act on fallopian tube motility aiding sperm capacitation, and ovum retention and transport. Early trials with PGs point to a possible action as an abortifacient, as a once-a-month contraceptive, or a postconception contraceptive agent. PGF2alpha is found in variable concentrations in maternal blood during contraction of the pregnant uterus; levels increase as labor progresses. PGs have been used for labor induction, for induction of abortion and in mole pregnancy. Given as a constant intravenous infusion they produce regular contractions leading to natural expulsion of the fetus and causing very few side effects in the woman with no adverse effects on the fetus. PGs' action compares favorably with that of oxytocin and is preferable for labor induction in certain pregnancy complications. PGE1

  18. Rosiglitazone and 15-deoxy-Delta12,14-prostaglandin J2, PPARgamma agonists, differentially regulate cigarette smoke-mediated pro-inflammatory cytokine release in monocytes/macrophages.

    PubMed

    Caito, Samuel; Yang, Se-Ran; Kode, Aruna; Edirisinghe, Indika; Rajendrasozhan, Saravanan; Phipps, Richard P; Rahman, Irfan

    2008-02-01

    Peroxisome Proliferator-Activated Receptor gamma (PPARgamma) ligands have the potential for use as anti-inflammatory agents in chronic airway diseases. We hypothesized that cigarette smoke (CS)-mediated pro-inflammatory cytokine release would be downregulated in the monocyte-macrophage cell line (MonoMac6) by synthetic and natural PPARgamma ligands. Surprisingly, treatment of MonoMac6 cells with the natural PPARgamma ligand 15-deoxy-Delta12,14-prostaglandin J2 led to increased cytokine (IL-8) release in response to either TNF-alpha or CS extract (CSE). However, exposure to rosiglitazone, a synthetic agonist, led to decreased TNF-alpha, but not CSE, mediated cytokine release. Cytokine release correlated with nuclear PPARgamma localization; CSE reduced the amount of activated PPARgamma located in the nucleus and formed aldehyde adducts as PPARgamma protein carbonyls. Furthermore, it was shown that PPARgamma interacts with the RelA/p65 subunit of NF-kappaB under TNF-alpha exposure conditions, but this interaction was disrupted by CS exposure, suggesting that CS blocks this important anti-inflammatory pathway involving PPARgamma. Thus, these new data show that activation of PPARgamma with natural or synthetic ligands have differential inhibitory effects on CS-mediated pro-inflammatory mediator release. These data have implications in designing therapies for treatment of COPD and pulmonary fibrosis. PMID:17970647

  19. Prostaglandins and their receptors in insect biology

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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 gr...

  20. Prostaglandin E specifically upregulates the expression of the mannose-receptor on mouse bone marrow-derived macrophages.

    PubMed Central

    Schreiber, S; Blum, J S; Chappel, J C; Stenson, W F; Stahl, P D; Teitelbaum, S L; Perkins, S L

    1990-01-01

    The macrophage mannose receptor (MMR) facilitates the binding and internalization of microorganisms and glycoproteins with terminal mannose residues. The receptor is progressively upregulated as bone marrow precursor cells mature into macrophages and thus may serve as a marker of differentiation. Prostaglandins of the E series (PGE) are known inhibitors of monocyte and macrophage precursor proliferation, an effect often associated with cellular maturation. MMR expression was therefore assessed after exposure of bone marrow macrophage precursor (BMMP) cells to these prostanoids. Receptor expression was determined by ligand binding and via immunoprecipitation of newly synthesized receptor molecules. PGE1 and PGE2 at 10(-9)-10(-6) M upregulated MMR surface expression and biosynthesis four- to sixfold in a dose-dependent manner. BMMPs responsive to prostaglandins were characterized by plastic adherence, F4/80 antigen expression, and nonspecific esterase activity. Prostaglandins accelerated the expression of the MMR in cells by 48-72h, with maximal levels of receptor expression being identical in control or treated cells. Thus, prostaglandins enhanced mannose receptor expression in adherent but not fully differentiated macrophage precursors. This effect is specific for PGE and is mimicked by dibutyrl cyclic AMP. These results indicate that prostaglandins accelerate MMR expression and hence the differentiation of macrophage precursor cells. Cells resident in the bone marrow secrete abundant prostaglandins, suggesting that a paracrine mechanism may exist to regulate MMR expression and function. Images PMID:1965946

  1. Lipopolysaccharide induces proinflammatory cytokines and chemokines in experimental otitis media through the prostaglandin D2 receptor (DP)-dependent pathway

    PubMed Central

    Eguchi, M; Kariya, S; Okano, M; Higaki, T; Makihara, S; Fujiwara, T; Nagata, K; Hirai, H; Narumiya, S; Nakamura, M; Nishizaki, K

    2011-01-01

    Otitis media is one of the most common and intractable ear diseases, and is the major cause of hearing loss, especially in children. Multiple factors affect the onset or development of otitis media. Prostaglandin D2 is the major prostanoid involved in infection and allergy. However, the role of prostaglandin D2 and prostaglandin D2 receptors on the pathogenesis of otitis media remains to be determined. Recent studies show that D prostanoid receptor (DP) and chemoattractant receptor-homologous molecule expressed on T helper type 2 (Th2) cells (CRTH2) are major prostaglandin D2 receptors. In this study, homozygous DP single gene-deficient (DP–/–) mice, CRTH2 single gene-deficient (CRTH2–/–) mice and DP/CRTH2 double gene-deficient (DP–/– CRTH2–/–) mice were used to investigate the role of prostaglandin D2 and its receptors in otitis media. We demonstrate that prostaglandin D2 is induced by lipopolysaccharide (LPS), a major component of Gram-negative bacteria, and that transtympanic injection of prostaglandin D2 up-regulates macrophage inflammatory protein 2 (MIP-2), interleukin (IL)-1β and IL-6 in the middle ear. We also show that middle ear inflammatory reactions, including infiltration of inflammatory cells and expression of MIP-2, IL-1β and IL-6 induced by LPS, are reduced significantly in DP–/– mice and DP–/– CRTH2–/– mice. CRTH2–/– mice display inflammatory reactions similar to wild-type mice. These findings indicate that prostaglandin D2 may play significant roles in LPS-induced experimental otitis media via DP. PMID:21166666

  2. Lipopolysaccharide induces proinflammatory cytokines and chemokines in experimental otitis media through the prostaglandin D2 receptor (DP)-dependent pathway.

    PubMed

    Eguchi, M; Kariya, S; Okano, M; Higaki, T; Makihara, S; Fujiwara, T; Nagata, K; Hirai, H; Narumiya, S; Nakamura, M; Nishizaki, K

    2011-02-01

    Otitis media is one of the most common and intractable ear diseases, and is the major cause of hearing loss, especially in children. Multiple factors affect the onset or development of otitis media. Prostaglandin D₂ is the major prostanoid involved in infection and allergy. However, the role of prostaglandin D₂ and prostaglandin D2 receptors on the pathogenesis of otitis media remains to be determined. Recent studies show that D prostanoid receptor (DP) and chemoattractant receptor-homologous molecule expressed on T helper type 2 (Th2) cells (CRTH2) are major prostaglandin D₂ receptors. In this study, homozygous DP single gene-deficient (DP⁻(/)⁻) mice, CRTH2 single gene-deficient (CRTH2⁻(/)⁻) mice and DP/CRTH2 double gene-deficient (DP⁻(/)⁻ CRTH2⁻(/)⁻) mice were used to investigate the role of prostaglandin D₂ and its receptors in otitis media. We demonstrate that prostaglandin D₂ is induced by lipopolysaccharide (LPS), a major component of Gram-negative bacteria, and that transtympanic injection of prostaglandin D₂ up-regulates macrophage inflammatory protein 2 (MIP-2), interleukin (IL)-1β and IL-6 in the middle ear. We also show that middle ear inflammatory reactions, including infiltration of inflammatory cells and expression of MIP-2, IL-1β and IL-6 induced by LPS, are reduced significantly in DP⁻(/)⁻ mice and DP⁻(/)⁻ CRTH2⁻(/)⁻ mice. CRTH2⁻(/)⁻ mice display inflammatory reactions similar to wild-type mice. These findings indicate that prostaglandin D₂ may play significant roles in LPS-induced experimental otitis media via DP. PMID:21166666

  3. Canine gastric mucosal vasodilation with prostaglandins and histamine analogs

    SciTech Connect

    Gerber, J.G.; Nies, A.S.

    1982-10-01

    The effect of direct intragastric artery infusion of prostaglandins E2 and I2, arachidonic acid, dimaprit (histamine H2 agonist), and 2',2'-pyridylethylamine (histamine H1 agonist) on gastric mucosal blood flow was examined in dogs to elucidate the relationship between gastric secretory state and mucosal blood flow in dogs. These compounds were chosen because of their diverse effect on gastric acid secretion. Gastric fundus blood flow was measured both electromagnetically with a flow probe around the left gastric artery which supplies the fundus almost exclusively, and by the radioactive microsphere technique. Intraarterial infusion of all the compounds resulted in gastric mucosal vasodilation even though PGE2, PGI2, and arachidonic acid inhibit gastric acid secretion, dimaprit stimulated gastric acid secretion, and 2',2'-pyridylethylamine does not affect gastric acid secretion. There was total agreement in the blood flow measurements by the two different techniques. Our data suggest that gastric acid secretion and gastric vasodilation are independently regulated. In addition, the validity of the studies in which the aminopyrine clearance indicates that prostaglandins are mucosal vasoconstrictors needs to be questioned because of the reliance of those measurements on the secretory state of the stomach.

  4. Effects of Camphorquinone on Cytotoxicity, Cell Cycle Regulation and Prostaglandin E2 Production of Dental Pulp Cells: Role of ROS, ATM/Chk2, MEK/ERK and Hemeoxygenase-1.

    PubMed

    Chang, Mei-Chi; Lin, Li-Deh; Wu, Min-Tsz; Chan, Chiu-Po; Chang, Hsiao-Hua; Lee, Ming-Shu; Sun, Tzu-Ying; Jeng, Po-Yuan; Yeung, Sin-Yuet; Lin, Hsueh-Jen; Jeng, Jiiang-Huei

    2015-01-01

    Camphorquinone (CQ) is a popularly-used photosensitizer in composite resin restoration. In this study, the effects of CQ on cytotoxicity and inflammation-related genes and proteins expression of pulp cells were investigated. The role of reactive oxygen species (ROS), ATM/Chk2/p53 and hemeoxygenase-1 (HO-1) and MEK/ERK signaling was also evaluated. We found that ROS and free radicals may play important role in CQ toxicity. CQ (1 and 2 mM) decreased the viability of pulp cells to about 70% and 50% of control, respectively. CQ also induced G2/M cell cycle arrest and apoptosis of pulp cells. The expression of type I collagen, cdc2, cyclin B, and cdc25C was inhibited, while p21, HO-1 and cyclooxygenase-2 (COX-2) were stimulated by CQ. CQ also activated ATM, Chk2, and p53 phosphorylation and GADD45α expression. Besides, exposure to CQ increased cellular ROS level and 8-isoprostane production. CQ also stimulated COX-2 expression and PGE2 production of pulp cells. The reduction of cell viability caused by CQ can be attenuated by N-acetyl-L-cysteine (NAC), catalase and superoxide dismutase (SOD), but can be promoted by Zinc protoporphyin (ZnPP). CQ stimulated ERK1/2 phosphorylation, and U0126 prevented the CQ-induced COX-2 expression and prostaglandin E2 (PGE2) production. These results indicate that CQ may cause cytotoxicity, cell cycle arrest, apoptosis, and PGE2 production of pulp cells. These events could be due to stimulation of ROS and 8-isoprostane production, ATM/Chk2/p53 signaling, HO-1, COX-2 and p21 expression, as well as the inhibition of cdc2, cdc25C and cyclin B1. These results are important for understanding the role of ROS in pathogenesis of pulp necrosis and pulpal inflammation after clinical composite resin filling. PMID:26658076

  5. Effects of Camphorquinone on Cytotoxicity, Cell Cycle Regulation and Prostaglandin E2 Production of Dental Pulp Cells: Role of ROS, ATM/Chk2, MEK/ERK and Hemeoxygenase-1

    PubMed Central

    Chang, Mei-Chi; Lin, Li-Deh; Wu, Min-Tsz; Chan, Chiu-Po; Chang, Hsiao-Hua; Lee, Ming-Shu; Sun, Tzu-Ying; Jeng, Po-Yuan; Yeung, Sin-Yuet; Lin, Hsueh-Jen; Jeng, Jiiang-Huei

    2015-01-01

    Camphorquinone (CQ) is a popularly-used photosensitizer in composite resin restoration. In this study, the effects of CQ on cytotoxicity and inflammation-related genes and proteins expression of pulp cells were investigated. The role of reactive oxygen species (ROS), ATM/Chk2/p53 and hemeoxygenase-1 (HO-1) and MEK/ERK signaling was also evaluated. We found that ROS and free radicals may play important role in CQ toxicity. CQ (1 and 2 mM) decreased the viability of pulp cells to about 70% and 50% of control, respectively. CQ also induced G2/M cell cycle arrest and apoptosis of pulp cells. The expression of type I collagen, cdc2, cyclin B, and cdc25C was inhibited, while p21, HO-1 and cyclooxygenase-2 (COX-2) were stimulated by CQ. CQ also activated ATM, Chk2, and p53 phosphorylation and GADD45α expression. Besides, exposure to CQ increased cellular ROS level and 8-isoprostane production. CQ also stimulated COX-2 expression and PGE2 production of pulp cells. The reduction of cell viability caused by CQ can be attenuated by N-acetyl-L-cysteine (NAC), catalase and superoxide dismutase (SOD), but can be promoted by Zinc protoporphyin (ZnPP). CQ stimulated ERK1/2 phosphorylation, and U0126 prevented the CQ-induced COX-2 expression and prostaglandin E2 (PGE2) production. These results indicate that CQ may cause cytotoxicity, cell cycle arrest, apoptosis, and PGE2 production of pulp cells. These events could be due to stimulation of ROS and 8-isoprostane production, ATM/Chk2/p53 signaling, HO-1, COX-2 and p21 expression, as well as the inhibition of cdc2, cdc25C and cyclin B1. These results are important for understanding the role of ROS in pathogenesis of pulp necrosis and pulpal inflammation after clinical composite resin filling. PMID:26658076

  6. Cyclic mechanical stretch augments prostacyclin production in cultured human uterine myometrial cells from pregnant women: possible involvement of up-regulation of prostacyclin synthase expression.

    PubMed

    Korita, Daizo; Sagawa, Norimasa; Itoh, Hiroaki; Yura, Shigeo; Yoshida, Masahiro; Kakui, Kazuyo; Takemura, Maki; Yokoyama, Chieko; Tanabe, Tadashi; Fujii, Shingo

    2002-11-01

    Prostacyclin (PGI(2)), a potent smooth muscle relaxant, is a major prostaglandin secreted from human myometrium. The concentrations of PGI(2) metabolites in the maternal plasma were reported to be elevated during pregnancy, especially in labor. To clarify the mechanism in PGI(2) secretion from the myometrium, we first investigated the protein expression of cytosolic phospholipase A(2), cyclooxygenase (COX)-1, COX-2, and prostacyclin synthase (PGIS) in the human uterine myometrium at various gestational ages before labor. To elucidate the involvement of labor in the increase in PGI(2) production during labor, we next examined the effect of labor-like cyclic mechanical stretch on PGI(2) production by cultured human myometrial cells. Pregnancy specifically increased COX-1 and PGIS protein expression in the myometrial tissues before labor (P < 0.01 for both). Cyclic mechanical stretch augmented PGIS promoter activity, via activation of activator protein-1 site, and PGIS mRNA and protein expression in cultured human myometrial cells and resulted in a 3.5-fold increase in the concentration of 6-keto-prostaglandin F(1alpha), the stable metabolite of PGI(2), in the culture medium (P < 0.05). However, stretch did not affect the levels of prostaglandin E(2), prostaglandin F(2alpha), or thromboxane A(2) secreted into the same culture media. These results suggest that cyclic mechanical stretch during labor may contribute to the increase in the PGI(2) concentration in the maternal plasma during parturition. PMID:12414894

  7. The role of nitric oxide in prostaglandin biology; update

    PubMed Central

    Kim, Sangwon F.

    2011-01-01

    The biosynthesis of nitric oxide (NO) and prostaglandin share many similarities. Two major forms of nitric oxide synthase (NOS) and cyclooxygenase (COX) have been identified: constitutive vs inducible. In general, the constitutive form functions in housekeeping and physiologic roles whereas the inducible form is up-regulated by mitogenic or inflammatory stimuli and is responsible for pathophysiological responses. The cross talk between the COX and NOS pathways was initially reported 1993 and since then, numerous studies have been undertaken to delineate the functional consequences of this interaction as well as the potential mechanism by which each pathway interacts. This review will focus in particular on recent advances in this field that extend our understanding of these two pathways under various systems. PMID:21820072

  8. The Role of Prostaglandins in Allergic Lung Inflammation and Asthma

    PubMed Central

    Claar, Dru; Hartert, Tina V.; Peebles, R. Stokes

    2015-01-01

    Prostaglandins are products of the cyclooxygenase pathway of arachidonic acid metabolism. There are five primary prostaglandins, PGD2, PGE2, PGF2, PGI2, and thromboxane B2, all of which signal through distinct seven transmembrane, G-protein coupled receptors. Some prostaglandins may counteract the actions of others, or even the same prostaglandin may have opposing physiologic or immunologic effects, depending on the specific receptor through which it signals. In this review, we will examine the effects of cyclooxygenase activity and the various prostaglandins on allergic airway inflammation and physiology that is associated with asthma. We also highlight the potential therapeutic benefit of targeting prostaglandins in allergic lung inflammation and asthma based on basic science, animal model, and human studies. PMID:25541289

  9. Time related changes in luteal prostaglandin synthesis and steroidogenic capacity during pregnancy, normal and antiprogestin induced luteolysis in the bitch.

    PubMed

    Kowalewski, Mariusz Pawel; Beceriklisoy, Hakki Bülent; Aslan, Selim; Agaoglu, Ali Reha; Hoffmann, Bernd

    2009-11-01

    In nonpregnant and pregnant dogs the corpora lutea (CL) are the only source of progesterone (P4) which shows an almost identical secretion pattern until the rapid decrease of P4 prior to parturition. For the nonpregnant dog clear evidence has been obtained that physiological luteal regression is devoid of a functional role of the PGF2alpha-system and seems to depend on the provision of StAR. Yet in pregnant dogs the rapid prepartal luteal regression, coinciding with an increase of PGF2alpha, may be indicative for different regulatory mechanisms. To assess this situation and by applying semi-quantitative Real Time (Taq Man) RT-PCR, expression patterns were determined for the following factors in CL of pregnant and prepartal dogs and of mid-pregnant dogs treated with the antiprogestin Aglepristone: cyclooxygenase 2 (Cox2), prostaglandin E2 synthase (PGES), prostaglandin F2alpha synthase (PGFS), its receptors (EP2, EP4 an FP), the steroidogenic acute regulatory protein (StAR), 3beta-hydroxysteroid-dehydrogenase (3betaHSD) and the progesterone receptor (PR). Peripheral plasma P4 concentrations were determined by RIA. CL were collected via ovariohysterectomy from pregnant bitches (n=3-5) on days 8-12 (Group 1, pre-implantation period), days 18-25 (Group 2, post-implantation period), days 35-40 (Group 3, mid-gestation period) and during the prepartal progesterone decline (Group 4). Additionally, CL were obtained from groups of 5 mid-pregnant dogs (days 40-45) 24h, respectively 72h after the second treatment with Aglepristone. Expression of Cox2 and PGES was highest during the pre-implantation period, that of PGFS and FP during the post-implantation period. EP4 and EP2 revealed a constant expression pattern throughout pregnancy with a prepartal upregulation of EP2. 3betaHSD and StAR decreased significantly from the pre-implatation period to prepartal luteolysis, it was matched by the course of P4 concentrations. Expression of the PR was higher during mid-gestation and

  10. The prostaglandin E2 receptor EP4 is integral to a positive feedback loop for prostaglandin E2 production in human macrophages infected with Mycobacterium tuberculosis

    PubMed Central

    Nishimura, Tomoyasu; Zhao, Xiaomin; Gan, Huixian; Koyasu, Shigeo; Remold, Heinz G.

    2013-01-01

    Prostaglandin E2 (PGE2) is an important biological mediator involved in the defense against Mycobacterium tuberculosis (Mtb) infection. Previously, we reported that in macrophages (Mφs), infection with avirulent Mtb H37Ra resulted in inhibition of necrosis by an inhibitory effect on mitochondrial permeability transition via the PGE2 receptor EP2. However, human Mφs also express EP4, a PGE2 receptor functionally closely related to EP2 that also couples to stimulatory guanine nucleotide binding protein, but the functional differences between EP2 and EP4 in Mtb-infected Mφs have been unclear. EP4 antagonist addition to H37Ra-infected Mφs inhibited the expression of cyclooxygenase 2 (COX2) and microsomal prostaglandin E synthase-1 (mPGES-1), which are involved in PGE2 production. Moreover, H37Ra infection induced PGE2 production through the Toll-like receptor (TLR) 2/p38 mitogen-activated protein kinase (MAPK) signaling pathway. Induction of COX2 and mPGES-1 expression by TLR2 stimulation or Mtb infection was increased after additional stimulation with EP4 agonist. Hence, in Mtb-infected Mφs, PGE2 production induced by pathogen recognition receptors/p38 MAPK signaling is up-regulated by EP4-triggered signaling to maintain an effective PGE2 concentration.—Nishimura, T., Zhao, X., Gan, H., Koyasu, S., and Remold, H. G. The prostaglandin E2 receptor EP4 is integral to a positive feedback loop for prostaglandin E2 production in human macrophages infected with Mycobacterium tuberculosis. PMID:23759445

  11. Prostaglandin E2-induced up-regulation of c-fos messenger ribonucleic acid is primarily mediated by 3',5'-cyclic adenosine monophosphate in MC3T3-E1 osteoblasts

    NASA Technical Reports Server (NTRS)

    Fitzgerald, J.; Dietz, T. J.; Hughes-Fulford, M.

    2000-01-01

    The mechanism by which the proto-oncogene, c-fos, is up-regulated in response to PGE2 in the mouse osteoblastic (MC3T3-E1) cell line was investigated using RT-PCR. c-fos messenger RNA up-regulation by dmPGE2 is rapid, starting 10 min post stimulation, and transient. The specific protein kinase A (PKA) inhibitor, H89, inhibited c-fos induction. Moreover, down-regulation of protein kinase C (PKC) activity by chronic TPA treatment had no effect on the induction of c-fos by dmPGE2. We conclude that up-regulation of c-fos by dmPGE2 is primarily dependent on PKA in MC3T3-E1 osteoblasts. In S49 lymphoma wild-type but not S49 cyc- cells, which are deficient in cAMP signaling, dmPGE2 up-regulates c-fos and increases cell growth compared with unstimulated cells. Thus in S49 lymphoma cells, c-fos induction by PGE2 is also dependent on cAMP signaling. The minimal c-fos promoter region required for dmPGE2-induced expression was identified by transfecting c-fos promoter deletion constructs coupled to the chloramphenicol acetyltransferase (CAT) reporter gene into Vero cells. Transfection of a plasmid containing 99 bp c-fos proximal promoter was sufficient to direct c-fos/CAT expression following stimulation with dmPGE2. Because induction of c-fos is mediated by cAMP, these data are consistent with activation of c-fos via the CRE/ATF cis element.

  12. Accumulation of ascorbate by endocrine-regulated and glucose-sensitive transport of dehydroascorbic acid in luteinized rat ovarian cells.

    PubMed

    Kodaman, P H; Aten, R F; Behrman, H R

    1998-02-01

    The corpus luteum is notable for very high levels of ascorbic acid. In luteal cells, ascorbic acid depletion occurs as a result of consumption during radical scavenging, inhibition of ascorbic acid uptake, and stimulation of its secretion. Oxidation of ascorbic acid generates dehydroascorbic acid (DHAA). Although levels of DHAA in blood are much lower than those of ascorbic acid, DHAA serves as the major transportable form of ascorbate for certain cell types. The aim of the present studies was to investigate whether DHAA transport is a potential mechanism for conserving ascorbic acid in the corpus luteum. DHAA uptake by rat luteal cells precultured for 24 h was linear for up to 30 min. Kinetics studies showed that uptake of DHAA was a concentration-dependent and saturable process with an estimated Michaelis constant (Km) of 830 microM and a maximum velocity (Vmax) of 700 pmol/min per 10(6) cells, a rate 50 times that of ascorbate transport. More than 90% of DHAA was reduced to ascorbic acid within 2 h of cellular uptake. DHAA uptake was energy- and microfilament-dependent, as transport was inhibited by 2,4-dinitrophenol (1 mM) and cytochalasin B (10 microM). Menadione (50 microM), an intracellular generator of reactive oxygen species, also markedly reduced DHAA uptake. In contrast to ascorbic acid transport, DHAA uptake was potently inhibited by glucose and phloretin, an inhibitor of glucose transporters, with IC50s of approximately 5 mM and 10 microM, respectively. DHAA uptake appears to occur via an insulin-insensitive transporter, as insulin (10 nM) had no effect on uptake. However, 24-h preincubation with insulin-like growth factor (IGF)-I dose-dependently (10-100 ng/ml) stimulated DHAA uptake; similar concentrations of IGF-II had no effect. The secretion of radioactivity by cells preloaded with radiolabeled DHAA was significantly increased by prostaglandin F2alpha (1 microM). The ability of luteal cells to transport DHAA in a regulated manner may serve to

  13. Protective effect of (±)α-tocopherol on brominated diphenyl ether-47-stimulated prostaglandin pathways in human extravillous trophoblasts in vitro.

    PubMed

    Park, Hae-Ryung; Loch-Caruso, Rita

    2015-10-01

    Brominated diphenyl ether (BDE)-47 is a prevalent flame retardant chemical found in human tissues and is linked to adverse pregnancy outcomes in humans. Because dysregulation of the prostaglandin pathway is implicated in adverse pregnancy outcomes, the present study investigates BDE-47 induction of prostaglandin synthesis in a human extravillous trophoblast cell line, HTR-8/SVneo, examining the hypothesis that BDE-47 increases generation of reactive oxygen species (ROS) to stimulate the prostaglandin response. Treatment with 20 μM BDE-47 significantly increased mRNA expression of prostaglandin-endoperoxide synthase 2 (PTGS2) at 4, 12 and 24 h, and 24-h treatment significantly increased cyclooxygenase (COX)-2 cellular protein expression and prostaglandin E2 (PGE2) concentration in culture medium. The BDE-47-stimulated PGE2 release was inhibited by the COX inhibitors indomethacin and NS398, implicating COX activity. Exposure to 20 μM BDE-47 significantly increased ROS generation as measured by carboxydichlorofluorescein fluorescence, and this response was blocked by cotreatment with the peroxyl radical scavenger (±)-α-tocopherol. (±)-α-Tocopherol cotreatment suppressed BDE-47-stimulated increases of PGE2 release without significant effects on COX-2 mRNA and protein expression, implicating a role for ROS in post-translational regulation of COX activity. Because prostaglandins regulate trophoblast functions necessary for placentation and pregnancy, further investigation is warranted of BDE-47 impacts on trophoblast responses. PMID:26026498

  14. Diverse Roles of Prostaglandins in Blastocyst Implantation

    PubMed Central

    2014-01-01

    Prostaglandins (PGs), derivatives of arachidonic acid, play an indispensable role in embryo implantation. PGs have been reported to participate in the increase in vascular permeability, stromal decidualization, blastocyst growth and development, leukocyte recruitment, embryo transport, trophoblast invasion, and extracellular matrix remodeling during implantation. Deranged PGs syntheses and actions will result in implantation failure. This review summarizes up-to-date literatures on the role of PGs in blastocyst implantation which could provide a broad perspective to guide further research in this field. PMID:24616654

  15. Prostaglandin E1 in hand angiography

    SciTech Connect

    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.

  16. The prostaglandin transporter (PGT) as a potential mediator of ovulation.

    PubMed

    Yerushalmi, Gil M; Markman, Svetlana; Yung, Yuval; Maman, Ettie; Aviel-Ronen, Sarit; Orvieto, Raoul; Adashi, Eli Y; Hourvitz, Ariel

    2016-05-11

    Prostaglandins (PGs) play an important role in the ovulatory process. However, the role of the PG transporter (PGT) in this context remains unknown. We report that the expression of PGT, a transmembrane PG carrier protein, is markedly up-regulated in preovulatory human granulosa cells (GCs). Treatment with human chorionic gonadotropin (hCG), an ovulatory trigger, significantly increases the expression of PGT mRNA and protein in human GCs both in vivo and in vitro. The hCG-induced increase in the expression of PGT in cultured human GCs is mediated via protein kinase A and protein kinase C by way of the extracellular signal-regulated kinase pathway. PGT in cultured human GCs mediates the uptake of PGE2, thereby regulating its extracellular concentration. In vivo treatment of mice with PGT inhibitors effectively blocks ovulation and markedly attenuates the expression of key ovulatory genes. We hypothesize that the inhibition of PGT activity in GCs increases the extracellular concentration of PGE2, the ability of which to exert its ovulatory effect is compromised by desensitization of its cognate receptors. Together, these findings support the idea that PGT is an important mediator of ovulation and that its inhibitors may be viewed as potential candidates for nonhormonal contraception. These findings may also fill the gap in the understanding of PGT signaling, enhance the understanding of ovulatory disorders, and facilitate the treatment of infertility or subfertility in women by using nonsteroidal PG-based therapeutic approaches. PMID:27169804

  17. Endogenous prostaglandin in guinea pig taenia coli.

    PubMed

    Yamaguchi, T; Hitzig, B; Coburn, R F

    1976-01-01

    Prostaglandin (PGE) is synthesized in the guinea pig taenia coli. A low threshold concentration for an effect of exogenous PGE1 or PGE2 on spontaneous mechanical activity was demonstrated. The PG synthetase inhibitors aspirin, indomethacin, and 5,8,11,14-eicosatetraynoic acid, at concentrations that inhibited PGE efflux, had effects on spontaneous mechanical activity, membrane potential, membrane resistance, and evoked and spontaneous action potentials (single and double sucrose-gap methods) that were consistent with an action due to inhibition of membrane PGE concentration. The threshold concentration of indomethacin, which inhibited PGE efflux, was the same as the concentration that inhibited spontaneous mechanical activity. Pretreatment with ouabain (10(-6)-10(-5) g/ml) or elevated extracellular K+ (29 and 126 mM) made the guinea pig taenia coli entirely refractory to exogenous PGE1 or PGE2; the mechanical effects of the three prostaglandin synthetase inhibitors also were absent in the presence of elevated K+ or ouabain. The data are consistent with a hypothesis that, under conditions of our experiments, endogenous PGE has an effect on resting tension and spontaneous mechanical activity and on properties of the surface membrane of the guinea pig taenia coli. PMID:1251900

  18. The effect of vitreous humour on prostaglandin production by cultured rabbit chorioretinal fibroblasts.

    PubMed

    Martin, C E; Croft, K D; van Bockxmeer, F M; Constable, I J

    1987-12-10

    Factors in vitreous humour which regulate prostaglandin production were investigated using cultured rabbit chorioretinal fibroblasts. These cells produced predominantly prostaglandin E2, 6-ketoprostaglandin F1 alpha, a compound likely to be a metabolite of prostaglandin E2 and 5-hydroxyeicosatetraenoic acid. The synthesis of 6-ketoprostaglandin F1 alpha was nearly completely inhibited by the cyclooxygenase inhibitor aspirin and partially inhibited by 10(-6) M dexamethasone (49%) and 10(-5) M forskolin (68%). Addition of 10% rabbit vitreous humour to subconfluent cells maintained in Dulbecco's modified Eagle's medium plus 1% fetal bovine serum resulted in stimulation of 6-ketoprostaglandin F1 alpha production by as much as 246% as measured by radioimmunoassay. Chorioretinal fibroblasts labelled by [3H]arachidonic acid incorporation into cellular phospholipids synthesised greater amounts of all labelled arachidonic acid metabolites in response to vitreous humour. It was concluded, therefore, that there are factors present in vitreous humour of molecular weight above 10 kDa which are capable of stimulating cellular cyclooxygenase activity. Confluent cells also responded to a factor(s) present in vitreous humour. The fraction of less than 10 kDa inhibited 6-ketoprostaglandin F1 alpha production by 50% when used at a concentration of 10%. Furthermore, 6-ketoprostaglandin F1 alpha production in confluent cells (but not subconfluent cells) was inhibited to 40% of control levels by vitamin C at a concentration of 1 mg/100 ml. The latter result points to an inhibitory role for vitamin C in vitreous humour. We conclude, therefore, that vitreous humour contains factors important for the regulation of prostaglandin metabolism in the eye. PMID:3118960

  19. Release of prostaglandins from the isolated frog ventricle and associated changes in endogenous cyclic nucleotide levels.

    PubMed Central

    Flitney, F W; Singh, J

    1980-01-01

    reached: thus, 8-bromo-3'5'-cyclic GMP accelerates the decline in contractility and depresses the steady-state level, whereas dibutyryl 3'5'-cyclic AMP delays the development of hypodynamic depression, and elevates the final twitch tension. The effects of both 3'5' cyclic nucleotide derivatives are dose-dependent. 7. The possible involvement of prostaglandins and 3'5'-cyclic nucleotides as causal agents in the mechanism of hypodynamic depression is discussed. The biochemical basis for the implied antangonistic effects of 3'5'-cyclic AMP and 3'5'-cyclic GMP in regulating ventricular contractility is considered in the following paper (Flitney & Singh, 1980). PMID:6255139

  20. Suppression of newborn natural killer cell activity by prostaglandin E2

    SciTech Connect

    Milch, P.O.; Salvatore, W.; Luft, B.; Baker, D.A.

    1988-10-01

    The effect of prostaglandin E2 on natural killer cell activity of cord blood was examined. Natural killer cell activity, determined by chromium 51 release, was significantly reduced after prostaglandin E2 (1 microgram/ml) treatment. Prostaglandin E2 has been found to enhance the cellular spread of herpesvirus. Thus prostaglandins may enhance viral infections indirectly by suppressing natural killer cell activity.

  1. Involvement of prostaglandins F/sub 2. cap alpha. / and E/sub 1/ with rabbit endometrium

    SciTech Connect

    Orlicky, D.J.

    1985-01-01

    Several growth factors and hormones are thought to play a role in the growth control of endometrial cells. The authors have shown that prostaglandin F/sub 2..-->../ (PGF/sub 2..cap alpha../) is a growth factor for primary cultures of rabbit endometrium cultured in chemically-defined serum-free medium and that prostaglandin E/sub 1/ (PGE/sub 1/) antagonizes the PGF/sub 2..-->../ induction of growth. Both (/sup 3/H)PGF/sub 2..cap alpha../ and (/sup 3/H)PGE/sub 1/ bind in a time and temperature dependent, dissociable, saturable and specific manner. The binding of (/sup 3/H)PGF/sub 2..cap alpha../ and (/sup 3/H)PGE/sub 1/ can be both down and up regulated and is enzyme sensitive. PGE /sub 1/ stimulates intracellular cAMP synthesis and accumulation in a time and concentration dependent manner. PGF/sub 2..cap alpha../ probably exerts its effects through an amiloride-sensitive intermediate. Both PGF/sub 2..cap alpha../ and PGE/sub 1/ are constitutively synthesized by these primary cultures, and they have shown this synthesis to be both drug and hormone sensitive. They hypothesize that it is the ratio, rather than the absolute quantities, of PGF/sub 2..cap alpha../ and PGE/sub 1/ which is of more importance in the regulation of endometrial cell growth. Furthermore, they believe this regulation of endometrial growth plays a role in control of proliferation during the decidual response and that a derangement in the ratio of these prostaglandins may lead to either infertility or hyperplasia. The ability of these cultures to synthesize prostaglandins in a hormonally regulatable manner may be of importance in the study of dysmenorrhea and uterine cramping as caused by the myometrial contracting prostaglandin, PGF/sub 2..cap alpha../.

  2. Reversible Conjunctival Pigmentation Associated With Prostaglandin Use.

    PubMed

    Choi, Daniel Y; Chang, Robert T; Yegnashankaran, Krishnan; Friedman, Neil J

    2016-01-01

    A 54-year-old Indian male with a diagnosis of ocular hypertension was started on a prostaglandin analog (PGA) in both eyes to lower intraocular pressure. Six years later, he developed progressively increasing bilateral limbal conjunctival hyperpigmentation. Travoprost was discontinued and replaced with brinzolamide and over the next year, the patient's conjunctival pigmentation improved significantly in both the eyes. This case report documents with slit-lamp photography the first case of conjunctival pigmentation associated with PGA use that has been shown to have reversal with discontinuation of the PGA. Because of the widespread use of PGAs, and the evolving nature of the conjunctival pigmentation, clinicians should be aware of this reversible condition when considering biopsy or removal of conjunctival melanocytic lesions. PMID:25967530

  3. Prostaglandins: a report on early clinical studies

    PubMed Central

    Hinman, J. W.

    1970-01-01

    The prostaglandins are a unique group of pharmacologically active lipids which are widely distributed in mammalian tissues and body fluids. The chemistry of this family of compounds has been established in elegant detail. Research quantities of these highly active natural compounds were obtained by enzymatic bioconversion of essential fatty acids and now studies devoted to the elucidation of their physiological roles and their clinical potential are progressing rapidly. Fields of greatest current interest in clinical medicine include renal-cardiovascular research, induction of labour and therapeutic abortion, control of the reproductive cycle (including fertility control), bronchodilation, enhancement of nasal patency and antisecretory activity. Results available to date are too preliminary for many conclusions to be drawn, but are sufficiently encouraging to assure continued and expanding efforts in several fields. PMID:4098885

  4. Antifibrotic Effects of Noscapine through Activation of Prostaglandin E2 Receptors and Protein Kinase A*

    PubMed Central

    Kach, Jacob; Sandbo, Nathan; La, Jennifer; Denner, Darcy; Reed, Eleanor B.; Akimova, Olga; Koltsova, Svetlana; Orlov, Sergei N.; Dulin, Nickolai O.

    2014-01-01

    Myofibroblast differentiation is a key process in the pathogenesis of fibrotic disease. We have shown previously that differentiation of myofibroblasts is regulated by microtubule polymerization state. In this work, we examined the potential antifibrotic effects of the antitussive drug, noscapine, recently found to bind microtubules and affect microtubule dynamics. Noscapine inhibited TGF-β-induced differentiation of cultured human lung fibroblasts (HLFs). Therapeutic noscapine treatment resulted in a significant attenuation of pulmonary fibrosis in the bleomycin model of the disease. Noscapine did not affect gross microtubule content in HLFs, but inhibited TGF-β-induced stress fiber formation and activation of serum response factor without affecting Smad signaling. Furthermore, noscapine stimulated a rapid and profound activation of protein kinase A (PKA), which mediated the antifibrotic effect of noscapine in HLFs, as assessed with the PKA inhibitor, PKI. In contrast, noscapine did not activate PKA in human bronchial or alveolar epithelial cells. Finally, activation of PKA and the antifibrotic effect of noscapine in HLFs were blocked by the EP2 prostaglandin E2 receptor antagonist, PF-04418948, but not by the antagonists of EP4, prostaglandin D2, or prostacyclin receptors. Together, we demonstrate for the first time the antifibrotic effect of noscapine in vitro and in vivo, and we describe a novel mechanism of noscapine action through EP2 prostaglandin E2 receptor-mediated activation of PKA in pulmonary fibroblasts. PMID:24492608

  5. Role of prostaglandins in the pathogenesis of X-linked hypophosphatemia.

    PubMed

    Baum, Michel; Syal, Ashu; Quigley, Raymond; Seikaly, Mouin

    2006-08-01

    X-linked hypophosphatemia is an X-linked dominant disorder resulting from a mutation in the PHEX gene. PHEX stands for phosphate-regulating gene with endopeptidase activity, which is located on the X chromosome. Patients with X-linked hypophosphatemia have hypophosphatemia due to renal phosphate wasting and low or inappropriately normal levels of 1,25-dihydroxyvitamin D. The renal phosphate wasting is not intrinsic to the kidney but likely due to an increase in serum levels of fibroblast growth factor-23 (FGF-23), and perhaps other phosphate-wasting peptides previously known as phosphatonins. Patients with X-linked hypophosphatemia have short stature, rickets, bone pain and dental abscesses. Current therapy is oral phosphate and vitamin D which effectively treats the rickets and bone pain but does not adequately improve short stature. In this review, we describe recent observations using Hyp mice; mice with the same mutation as patients with X-linked hypophosphatemia. We have recently found that Hyp mice have abnormal renal prostaglandin production, which may be an important factor in the pathogenesis of this disorder. Administration of FGF-23 in vivo results in phosphaturia and an increase in prostaglandin excretion, and FGF-23 increases proximal tubule prostaglandin production in vitro. In Hyp mice, indomethacin improves the phosphate transport defect in vitro and in vivo. Whether indomethacin has the same effect in patients with X-linked hypophosphatemia is unknown. PMID:16721588

  6. Antifibrotic effects of noscapine through activation of prostaglandin E2 receptors and protein kinase A.

    PubMed

    Kach, Jacob; Sandbo, Nathan; La, Jennifer; Denner, Darcy; Reed, Eleanor B; Akimova, Olga; Koltsova, Svetlana; Orlov, Sergei N; Dulin, Nickolai O

    2014-03-14

    Myofibroblast differentiation is a key process in the pathogenesis of fibrotic disease. We have shown previously that differentiation of myofibroblasts is regulated by microtubule polymerization state. In this work, we examined the potential antifibrotic effects of the antitussive drug, noscapine, recently found to bind microtubules and affect microtubule dynamics. Noscapine inhibited TGF-β-induced differentiation of cultured human lung fibroblasts (HLFs). Therapeutic noscapine treatment resulted in a significant attenuation of pulmonary fibrosis in the bleomycin model of the disease. Noscapine did not affect gross microtubule content in HLFs, but inhibited TGF-β-induced stress fiber formation and activation of serum response factor without affecting Smad signaling. Furthermore, noscapine stimulated a rapid and profound activation of protein kinase A (PKA), which mediated the antifibrotic effect of noscapine in HLFs, as assessed with the PKA inhibitor, PKI. In contrast, noscapine did not activate PKA in human bronchial or alveolar epithelial cells. Finally, activation of PKA and the antifibrotic effect of noscapine in HLFs were blocked by the EP2 prostaglandin E2 receptor antagonist, PF-04418948, but not by the antagonists of EP4, prostaglandin D2, or prostacyclin receptors. Together, we demonstrate for the first time the antifibrotic effect of noscapine in vitro and in vivo, and we describe a novel mechanism of noscapine action through EP2 prostaglandin E2 receptor-mediated activation of PKA in pulmonary fibroblasts. PMID:24492608

  7. Interactions between ADH and prostaglandins in isolated erythrocyte-perfused rat kidney

    SciTech Connect

    Lieberthal, W.; Vasilevsky, M.L.; Valeri, C.R.; Levinsky, N.G.

    1987-02-01

    Interactions between antidiuretic hormone (ADH) and renal prostaglandins in the regulation of sodium reabsorption and urinary concentrating ability were studied in isolated erythrocyte-perfused rat kidneys (IEPK). In this model, hemodynamic characteristics are comparable to those found in vivo, and tubular morphology is preserved throughout the period of perfusion. (Deamino)-D-arginine vasopressin (dDAVP) markedly reduced fractional sodium excretion (FE/sub Na/) in the IEPK. After indomethacin, FE/sub Na/ fell still further. In the absence of dDAVP indomethacin had no effect on sodium excretion. dDAVP increased urine osmolality in the IEPK. When prostaglandin synthesis was blocked with indomethacin, urinary osmolality increased further. In isolated kidneys perfused without erythrocytes (IPK), dDAVP decreased FE/sub Na/ from 14.5 +/- 1.8% to 9.6 +/- 1.2%. dDAVP increased urine osmolality only modestly in the IPK and indomethacin did not increase concentrating ability further. Thus the IEPK (unlike the IPK) can excrete markedly hypertonic urine in response to ADH. ADH also enhances tubular reabsorption of sodium in the IEPK. Prostaglandins inhibit both these actions of ADH but do not directly affect sodium excretion in the absence of the hormone. Prostaglandius were measured by radioimmunoassay.

  8. Effects of Prostaglandin Analogues on Aqueous Humor Outflow Pathways

    PubMed Central

    Winkler, Nelson S.

    2014-01-01

    Abstract Elevated intraocular pressure (IOP) is the most prevalent risk factor for glaucoma. All treatments, whether surgical or pharmaceutical, are aimed at lowering IOP. Prostaglandin analogues are a first line therapy for glaucoma due to their ability to reduce IOP, once-daily dosing, efficacy, and minimal side-effect profile. Whereas prostaglandin analogues have been known to alter aqueous humor outflow through the unconventional (uveoscleral) pathway, more recent evidence suggests their action also occurs through the conventional (trabecular) pathway. Understanding how prostaglandin analogues successfully lower IOP is important, as this information may lead to the discovery of new molecular targets for future therapeutic intervention. This review explores the current understanding of prostaglandin analogue biology as it pertains to IOP reduction and improved aqueous humor outflow facility. PMID:24359106

  9. Angiotensin II induced release of prostaglandins from rat uterus.

    PubMed

    Campos, G A; Guerra, F A; Israel, E J

    1983-08-01

    The effect of Angiotensin II (A-II) on 6-keto-prostaglandin F1 (6-keto-PGF1 alpha) and prostaglandin F (PGF) production by the rat uterus was studied using a novel superfusion technique. The method of superfusion used allows prostaglandin synthesis in the myometrium and endometrium to be measured independently while their anatomical relationship is undisturbed. Prostaglandins were measured by radioimmunoassay. In uterine horns from castrated, estrogen treated rats, A-II (10(-6)M) stimulated the production rate of 6-keto-PGF1 alpha in the myometrium nd PGF in the endometrium. Sterile horns and pregnant horns coexisting in the same animals showed different responses when superfused with culture medium containing A-II (10(-6)M). In the sterile horns A-II failed to stimulate prostaglandin synthesis whereas in the pregnant horns there was a significant increase in the production rate of both 6-keto-PGF1 alpha and PGF in the decidua (endometrium) and of 6-keto-PGF1 alpha in the myometrium. Our results suggests that the effect of A-II on prostaglandin synthesis by the rat uterus appears to be dependent of the hormonal milieu of the experimental animal. Estrogen stimulated A-II induced PG synthesis. Progesterone inhibited the synthesis of PGs caused by A-II in non-decidualized uterus but stimulated the release of PG in the decidualized uterus. The apparent differential effect of A-II in stimulating prostaglandin synthesis in the whole uterus indicates that there are different pathways for prostaglandin production in both the endometrium and myometrium. PMID:6689628

  10. Prostaglandin signaling suppresses beneficial microglial function in Alzheimer's disease models.

    PubMed

    Johansson, Jenny U; Woodling, Nathaniel S; Wang, Qian; Panchal, Maharshi; Liang, Xibin; Trueba-Saiz, Angel; Brown, Holden D; Mhatre, Siddhita D; Loui, Taylor; Andreasson, Katrin I

    2015-01-01

    Microglia, the innate immune cells of the CNS, perform critical inflammatory and noninflammatory functions that maintain normal neural function. For example, microglia clear misfolded proteins, elaborate trophic factors, and regulate and terminate toxic inflammation. In Alzheimer's disease (AD), however, beneficial microglial functions become impaired, accelerating synaptic and neuronal loss. Better understanding of the molecular mechanisms that contribute to microglial dysfunction is an important objective for identifying potential strategies to delay progression to AD. The inflammatory cyclooxygenase/prostaglandin E2 (COX/PGE2) pathway has been implicated in preclinical AD development, both in human epidemiology studies and in transgenic rodent models of AD. Here, we evaluated murine models that recapitulate microglial responses to Aβ peptides and determined that microglia-specific deletion of the gene encoding the PGE2 receptor EP2 restores microglial chemotaxis and Aβ clearance, suppresses toxic inflammation, increases cytoprotective insulin-like growth factor 1 (IGF1) signaling, and prevents synaptic injury and memory deficits. Our findings indicate that EP2 signaling suppresses beneficial microglia functions that falter during AD development and suggest that inhibition of the COX/PGE2/EP2 immune pathway has potential as a strategy to restore healthy microglial function and prevent progression to AD. PMID:25485684

  11. Renal Effects of Prostaglandins and Cyclooxygenase-2 Inhibitors

    PubMed Central

    2008-01-01

    Prostaglandins (PGs) with best-defined renal functions are PGE2 and prostacyclin (PGI2). These vasodilatory PGs increase renal blood flow and glomerular filtration rate under conditions associated with decreased actual or effective circulating volume, resulting in greater tubular flow and secretion of potassium. Under conditions of decreased renal perfusion, the production of renal PGs serves as an important compensatory mechanism. PGI2 (and possibly PGE2) increases potassium secretion mainly by stimulating secretion of renin and activating the renin-angiotensin system, which leads to increased secretion of aldosterone. In addition, PGE2 is involved in the regulation of sodium and water reabsorption and acts as a counterregulatory factor under conditions of increased sodium reabsorption. PGE2 decreases sodium reabsorption at the thick ascending limb of the loop of Henle probably via inhibition of the Na+-K+-2Cl- cotransporter type 2 (NKCC2). Cyclooxygenase inhibitors may enhance urinary concentrating ability in part through effects to upregulate NKCC2 in the thick ascending limb of Henle's loop and aquaporin-2 in the collecting duct. Thus, they may be useful to treat Bartter's syndrome and nephrogenic diabetes insipidus. PMID:24459520

  12. Prostaglandin E2 Regulation of Macrophage Innate Immunity.

    PubMed

    Kimmel, Danielle W; Rogers, Lisa M; Aronoff, David M; Cliffel, David E

    2016-01-19

    Globally, maternal and fetal health is greatly impacted by extraplacental inflammation. Group B Streptococcus (GBS), a leading cause of chorioamnionitis, is thought to take advantage of the uterine environment during pregnancy in order to cause inflammation and infection. In this study, we demonstrate the metabolic changes of murine macrophages caused by GBS exposure. GBS alone prompted a delayed increase in lactate production, highlighting its ability to redirect macrophage metabolism from aerobic to anaerobic respiration. This production of lactate is thought to aid in the development and propagation of GBS throughout the surrounding tissue. Additionally, this study shows that PGE2 priming was able to exacerbate lactate production, shown by the rapid and substantial lactate increases seen upon GBS exposure. These data provide a novel model to study the role of GBS exposure to macrophages with and without PGE2 priming. PMID:26656203

  13. Simulated microgravity upregulates an endothelial vasoconstrictor prostaglandin.

    PubMed

    Sangha, D S; Han, S; Purdy, R E

    2001-08-01

    Endothelial nitric oxide contributes to the vascular hyporesponsiveness to norepinephrine (NE) observed in carotid arteries from rats exposed to simulated microgravity. The goal of the present study was to determine whether a cyclooxygenase product of arachidonic acid also influences vascular responsiveness in this setting. Microgravity was simulated in rats by hindlimb unweighting (HU). After 20 days of HU, carotid arteries were isolated from control and HU-treated rats, and vascular rings were mounted in tissue baths for the measurement of isometric contraction. Two cyclooxygenase inhibitors, indomethacin and ibuprofen, and the selective thromboxane A(2) prostanoid-receptor antagonist, SQ-29548, had no effect on the contraction to NE in control vessels but markedly reduced contraction to NE in HU vessels. When the endothelium was removed, indomethacin no longer had any effect on the NE-induced contraction in HU vessels. In endothelium-intact vessels in the presence of indomethacin, the addition of the nitric oxide synthase inhibitor, N(G)-L-nitro-arginine methyl ester, to the medium bathing HU vessels increased the contraction to NE to the level of that of the control vessels. These results indicate that HU treatment induced two endothelial changes in carotid artery that opposed each other. Nitric oxide activity was increased and was responsible for the vascular hyporesponsiveness to NE. The activity of a vasoconstrictor prostaglandin was also increased, and attenuated the vasodilating effect of nitric oxide. PMID:11457795

  14. Simulated microgravity upregulates an endothelial vasoconstrictor prostaglandin

    NASA Technical Reports Server (NTRS)

    Sangha, D. S.; Han, S.; Purdy, R. E.

    2001-01-01

    Endothelial nitric oxide contributes to the vascular hyporesponsiveness to norepinephrine (NE) observed in carotid arteries from rats exposed to simulated microgravity. The goal of the present study was to determine whether a cyclooxygenase product of arachidonic acid also influences vascular responsiveness in this setting. Microgravity was simulated in rats by hindlimb unweighting (HU). After 20 days of HU, carotid arteries were isolated from control and HU-treated rats, and vascular rings were mounted in tissue baths for the measurement of isometric contraction. Two cyclooxygenase inhibitors, indomethacin and ibuprofen, and the selective thromboxane A(2) prostanoid-receptor antagonist, SQ-29548, had no effect on the contraction to NE in control vessels but markedly reduced contraction to NE in HU vessels. When the endothelium was removed, indomethacin no longer had any effect on the NE-induced contraction in HU vessels. In endothelium-intact vessels in the presence of indomethacin, the addition of the nitric oxide synthase inhibitor, N(G)-L-nitro-arginine methyl ester, to the medium bathing HU vessels increased the contraction to NE to the level of that of the control vessels. These results indicate that HU treatment induced two endothelial changes in carotid artery that opposed each other. Nitric oxide activity was increased and was responsible for the vascular hyporesponsiveness to NE. The activity of a vasoconstrictor prostaglandin was also increased, and attenuated the vasodilating effect of nitric oxide.

  15. Sulforaphane Inhibits Prostaglandin E2 Synthesis by Suppressing Microsomal Prostaglandin E Synthase 1

    PubMed Central

    Zhou, Jiping; Joplin, Denise G.; Cross, Janet V.; Templeton, Dennis J.

    2012-01-01

    Sulforaphane (SFN) is a dietary cancer preventive with incompletely characterized mechanism(s) of cancer prevention. Since prostaglandin E2 (PGE2) promotes cancer progression, we hypothesized that SFN may block PGE2 synthesis in cancer cells. We found that SFN indeed blocked PGE2 production in human A549 cancer cells not by inhibiting COX-2, but rather by suppressing the expression of microsomal prostaglandin E synthase (mPGES-1), the enzyme that directly synthesizes PGE2. We identified the Hypoxia Inducible Factor 1 alpha (HIF-1α) as the target of SFN-mediated mPGES-1 suppression. SFN suppressed HIF-1α protein expression and the presence of HIF-1α at the mPGES-1 promoter, resulting in reduced transcription of mPGES-1. Finally, SFN also reduced expression of mPGES-1 and PGE2 production in A549 xenograft tumors in mice. Together, these results point to the HIF-1α, mPGES-1 and PGE2 axis as a potential mediator of the anti-cancer effects of SFN, and illustrate the potential of SFN for therapeutic control of cancer and inflammation. Harmful side effects in patients taking agents that target the more upstream COX-2 enzyme render the downstream target mPGES-1 a significant target for anti-inflammatory therapy. Thus, SFN could prove to be an important therapeutic approach to both cancer and inflammation. PMID:23166763

  16. Prostaglandin I2 Attenuates Prostaglandin E2-Stimulated Expression of Interferon γ in a β-Amyloid Protein- and NF-κB-Dependent Mechanism

    PubMed Central

    Wang, Pu; Guan, Pei-Pei; Yu, Xin; Zhang, Li-Chao; Su, Ya-Nan; Wang, Zhan-You

    2016-01-01

    Cyclooxygenase-2 (COX-2) has been recently identified as being involved in the pathogenesis of Alzheimer’s disease (AD). However, the role of an important COX-2 metabolic product, prostaglandin (PG) I2, in AD development remains unknown. Using mouse-derived astrocytes as well as APP/PS1 transgenic mice as model systems, we firstly elucidated the mechanisms of interferon γ (IFNγ) regulation by PGE2 and PGI2. Specifically, PGE2 accumulation in astrocytes activated the ERK1/2 and NF-κB signaling pathways by phosphorylation, which resulted in IFNγ expression. In contrast, the administration of PGI2 attenuated the effects of PGE2 on stimulating the production of IFNγ via inhibiting the translocation of NF-κB from the cytosol to the nucleus. Due to these observations, we further studied these prostaglandins and found that both PGE2 and PGI2 increased Aβ1–42 levels. In detail, PGE2 induced IFNγ expression in an Aβ1–42-dependent manner, whereas PGI2-induced Aβ1–42 production did not alleviate cells from IFNγ inhibition by PGI2 treatment. More importantly, our data also revealed that not only Aβ1–42 oligomer but also fibrillar have the ability to induce the expression of IFNγ via stimulation of NF-κB nuclear translocation in astrocytes of APP/PS1 mice. The production of IFNγ finally accelerated the deposition of Aβ1–42 in β-amyloid plaques. PMID:26869183

  17. Cyclooxygenase-2 and Prostaglandin E2 Signaling through Prostaglandin Receptor EP-2 Favor the Development of Myocarditis during Acute Trypanosoma cruzi Infection

    PubMed Central

    Guerrero, Néstor A.; Camacho, Mercedes; Vila, Luis; Íñiguez, Miguel A.; Chillón-Marinas, Carlos; Cuervo, Henar; Poveda, Cristina; Fresno, Manuel; Gironès, Núria

    2015-01-01

    Inflammation plays an important role in the pathophysiology of Chagas disease, caused by Trypanosoma cruzi. Prostanoids are regulators of homeostasis and inflammation and are produced mainly by myeloid cells, being cyclooxygenases, COX-1 and COX-2, the key enzymes in their biosynthesis from arachidonic acid (AA). Here, we have investigated the expression of enzymes involved in AA metabolism during T. cruzi infection. Our results show an increase in the expression of several of these enzymes in acute T. cruzi infected heart. Interestingly, COX-2 was expressed by CD68+ myeloid heart-infiltrating cells. In addition, infiltrating myeloid CD11b+Ly6G- cells purified from infected heart tissue express COX-2 and produce prostaglandin E2 (PGE2) ex vivo. T. cruzi infections in COX-2 or PGE2-dependent prostaglandin receptor EP-2 deficient mice indicate that both, COX-2 and EP-2 signaling contribute significantly to the heart leukocyte infiltration and to the release of chemokines and inflammatory cytokines in the heart of T. cruzi infected mice. In conclusion, COX-2 plays a detrimental role in acute Chagas disease myocarditis and points to COX-2 as a potential target for immune intervention. PMID:26305786

  18. The prostaglandin E2 receptor EP4 is integral to a positive feedback loop for prostaglandin E2 production in human macrophages infected with Mycobacterium tuberculosis.

    PubMed

    Nishimura, Tomoyasu; Zhao, Xiaomin; Gan, Huixian; Koyasu, Shigeo; Remold, Heinz G

    2013-09-01

    Prostaglandin E2 (PGE2) is an important biological mediator involved in the defense against Mycobacterium tuberculosis (Mtb) infection. Previously, we reported that in macrophages (Mϕs), infection with avirulent Mtb H37Ra resulted in inhibition of necrosis by an inhibitory effect on mitochondrial permeability transition via the PGE2 receptor EP2. However, human Mϕs also express EP4, a PGE2 receptor functionally closely related to EP2 that also couples to stimulatory guanine nucleotide binding protein, but the functional differences between EP2 and EP4 in Mtb-infected Mϕs have been unclear. EP4 antagonist addition to H37Ra-infected Mϕs inhibited the expression of cyclooxygenase 2 (COX2) and microsomal prostaglandin E synthase-1 (mPGES-1), which are involved in PGE2 production. Moreover, H37Ra infection induced PGE2 production through the Toll-like receptor (TLR) 2/p38 mitogen-activated protein kinase (MAPK) signaling pathway. Induction of COX2 and mPGES-1 expression by TLR2 stimulation or Mtb infection was increased after additional stimulation with EP4 agonist. Hence, in Mtb-infected Mϕs, PGE2 production induced by pathogen recognition receptors/p38 MAPK signaling is up-regulated by EP4-triggered signaling to maintain an effective PGE2 concentration. PMID:23759445

  19. Anti-inflammatory role of microsomal prostaglandin E synthase-1 in a model of neuroinflammation.

    PubMed

    Brenneis, Christian; Coste, Ovidiu; Altenrath, Kai; Angioni, Carlo; Schmidt, Helmut; Schuh, Claus-Dieter; Zhang, Dong Dong; Henke, Marina; Weigert, Andreas; Brüne, Bernhard; Rubin, Barry; Nusing, Rolf; Scholich, Klaus; Geisslinger, Gerd

    2011-01-21

    A major immunological response during neuroinflammation is the activation of microglia, which subsequently release proinflammatory mediators such as prostaglandin E(2) (PGE(2)). Besides its proinflammatory properties, cyclooxygenase-2 (COX-2)-derived PGE(2) has been shown to exhibit anti-inflammatory effects on innate immune responses. Here, we investigated the role of microsomal PGE(2) synthase-1 (mPGES-1), which is functionally coupled to COX-2, in immune responses using a model of lipopolysaccharide (LPS)-induced spinal neuroinflammation. Interestingly, we found that activation of E-prostanoid (EP)2 and EP4 receptors, but not EP1, EP3, PGI(2) receptor (IP), thromboxane A(2) receptor (TP), PGD(2) receptor (DP), and PGF(2) receptor (FP), efficiently blocked LPS-induced tumor necrosis factor α (TNFα) synthesis and COX-2 and mPGES-1 induction as well as prostaglandin synthesis in spinal cultures. In vivo, spinal EP2 receptors were up-regulated in microglia in response to intrathecally injected LPS. Accordingly, LPS priming reduced spinal synthesis of TNFα, interleukin 1β (IL-1β), and prostaglandins in response to a second intrathecal LPS injection. Importantly, this reduction was only seen in wild-type but not in mPGES-1-deficient mice. Furthermore, intrathecal application of EP2 and EP4 agonists as well as genetic deletion of EP2 significantly reduced spinal TNFα and IL-1β synthesis in mPGES-1 knock-out mice after LPS priming. These data suggest that initial inflammation prepares the spinal cord for a negative feedback regulation by mPGES-1-derived PGE(2) followed by EP2 activation, which limits the synthesis of inflammatory mediators during chronic inflammation. Thus, our data suggest a role of mPGES-1-derived PGE(2) in resolution of neuroinflammation. PMID:21075851

  20. Production of prostaglandins in placentae and corpus luteum in pregnant hinds of red deer (Cervus elaphus).

    PubMed

    Korzekwa, A J; Szczepańska, A; Bogdaszewski, M; Nadolski, P; Malż, P; Giżejewski, Z

    2016-03-01

    Prostaglandins (PGs) are synthesized from arachidonic acid by prostaglandin synthase 2 (PTGS2) and specific terminal PG synthases such as PGES and PGFS. The role of PGs in the reproductive processes of domestic ruminants is well recognized, whereas in cervidae, it is almost unknown, although it is noteworthy because some species of this family are valued in meat production and trophies. The aim of this study was to determine an effective marker of pregnancy and investigate the production and secretion of PGs in placenta and CL tissue in pregnancy. In the preliminary experiment, the levels of progesterone and 17-β estradiol (RIA; N = 14 divided into seven pregnant and seven nonpregnant hinds) were measured in the peripheral blood. In the main experiment, a comparison of messenger RNA (real-time polymerase chain reaction) and protein expression (Western blotting) of PTGS2, PGES, and PGFS, the level of prostaglandin E2 (PGE2) and PGF2α in the placentae and CL in pregnant hinds (aged 3-4 years, ca. 100 days of pregnancy, N = 6). In pregnant hinds, the level of progesterone in the blood was higher than that in nonpregnant hinds (P < 0.05), whereas the level of E2 was similar in all animals (P > 0.05). The highest messenger RNA expression of PTGS2, PGES, and PGFS was observed in the placentae than in the CL (P < 0.05). The protein expression of PTGS2 and PGES was elevated in the placentae compared with the CL (P < 0.05). The PGE2 output was the highest in cotyledonary tissue (P < 0.05). Pregnancy development in hinds around 100 days is regulated by arachidonic acid metabolites, especially PGE2 produced by the placentae, which production increases in pregnancy. Further studies are required to unravel the mechanisms involved in the regulation of PG and biosynthetic enzymes in uteroplacental and ovarian tissues during pregnancy in red deer females. PMID:26553568

  1. Impotence evaluated by the use of prostaglandin E1

    SciTech Connect

    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.

  2. Is brain prostaglandin synthesis involved in responses to cold?

    PubMed Central

    Cranston, W I; Hellon, R F; Mitchell, D

    1975-01-01

    1. Experiments with rats have suggested that prostaglandin synthesis in the C.N.S. may mediate thermoregulatory reactions to cold. This possibility was investigated in cats using two types of experiment. 2. In one series of experiments, c.s.f. collected from the cisterna magna of conscious cats exposed to a cold and a hot environment was assayed for prostaglandin-like activity. During cold exposure there was a slight increase in activity which persisted after return to neutral ambient temperature. There was no correlation between prostaglandin-like activity and rectal temperature. During the heat exposure there was no demonstrable change in activity. 3. In the second series, conscious cats were exposed to cold conditions and given intravenous injections of salicylate, paracetamol, or indomethacin, all of which inhibit prostaglandin synthesis. Indomethacin salicylate nor paracetamol caused any significant change in rectal temperature. 4. The results do not support a role for C.N.S. prostaglandin synthesis in thermoregulatory reactions to cold in cats. PMID:1177099

  3. Prostaglandins and Their Receptors in Insect Biology

    PubMed Central

    Stanley, David; Kim, Yonggyun

    2011-01-01

    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. 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. 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. We conclude that research into PGs and their receptors in insects will lead to important advances in our understanding of insect biology. PMID:22654840

  4. Many Putative Endocrine Disruptors Inhibit Prostaglandin Synthesis

    PubMed Central

    Kristensen, David M.; Skalkam, Maria L.; Audouze, Karine; Lesné, Laurianne; Desdoits-Lethimonier, Christele; Frederiksen, Hanne; Brunak, Søren; Skakkebæk, Niels E.; Jégou, Bernard; Hansen, Jacob B.; Junker, Steffen; Leffers, Henrik

    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 degree of structural similarity with mild analgesics. Objectives and Methods Using cell-based transfection and transduction experiments, mass spectrometry, and organotypic assays together with molecular modeling, we investigated whether inhibition of the PG pathway by known EDCs could be a novel point 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 this reduction was correlated with a reduced testosterone production. The inhibition of PG synthesis occurred without involvement of canonical PG receptors or the peroxisome proliferator–activated receptors (PPARs), which have previously been described as targets of EDCs. Instead, our results suggest that the compounds may bind directly into the active site of the cyclooxygenase (COX) enzymes, thereby obstructing the conversion of arachidonic acid to PG precursors without interfering with the expression of the COX enzymes. A common feature of the PG inhibitory EDCs is the presence of aromatic groups that may stabilize binding in the hydrophobic active site of the COX enzymes. Conclusion Our findings suggest a hitherto unknown mode of action by EDCs through inhibition of the PG pathway and suggest new avenues to investigate effects of EDCs on reproductive and immunological disorders that have become increasingly common in recent decades. PMID:21081300

  5. Prostaglandin E2 modulation of rheumatoid factor synthesis.

    PubMed

    Alvarellos, A; Lipsky, P E; Jasin, H E

    1988-12-01

    We examined the influence of prostaglandin E2 (PGE2) on the in vitro synthesis of rheumatoid factor (RF) by purified human B and T lymphocytes stimulated with Staphylococcus aureus Cowan 1 or pokeweed mitogen (PWM). Supernatants were assayed for total IgM and RF. PGE2 at concentrations of 10(-7) M to 10(-9) M significantly inhibited RF and IgM secretion stimulated by S aureus Cowan 1, a cross-linker of B cell surface Ig. The magnitude of inhibition of RF production was significantly greater than that of total IgM at low PGE2 concentrations (P less than 0.05). In contrast, PWM-stimulated cultures were only minimally inhibited by PGE2 at all concentrations tested. Since cross-linking of surface Ig renders B cells more susceptible to inhibition by PGE2, heat-aggregated IgG (HAIgG) was added to the PWM-stimulated cultures in an attempt to increase the sensitivity of precursors of RF-secreting cells to the inhibitory effects of PGE2. Addition of HAIgG markedly increased PGE2-mediated inhibition of RF synthesis without significantly affecting IgM production. Inhibition could not be overcome by the addition of soluble T helper cell factors, indicating that PGE2-mediated suppression was not the result of an inhibitory action of T helper cells. When lymphocytes from patients with rheumatoid arthritis were examined, HAIgG was found to be unable to induce sensitivity to PGE2-mediated inhibition of responsiveness. These results suggest that down-regulation of RF synthesis requires both cross-linking of surface Ig and the influence of PGE2. Abnormalities in this immunoregulatory mechanism may explain the ongoing production of RF in patients with rheumatoid arthritis. PMID:3264162

  6. Chromosomal organization of the inducible and constitutive prostaglandin synthase/cyclooxygenase genes in mouse

    SciTech Connect

    Ping Zi Wen; Warden C.; Fletcher, B.S.; Kujubu, D.A.; Herschman, H.R.; Lusis, A.J. )

    1993-02-01

    Two distinct prostaglandin synthase/cyclooxygenase (PGS/COS) enzymes have recently been recognized. One (EC 1.14.00.1) is largely constitutive and has been characterized in a variety of species, whereas the other (also known as TIS10) is inducible by mitogens and inhibitable by glucocorticoids. Along with activation of phospholipase A2, the latter PGS/COS is likely to mediate ligand-induced prostaglandin production in a variety of cell types. The two enzymes have similar gene structures and activities. There is accumulating evidence that PGS/COX activity may play a role in inflammatory diseases. For example, PGS/COX expression is upregulated in inflammatory joint diseases and is genetically controlled. As part of an effort to examine genetic factors regulating PGS/COX expression and the possible involvement of the enzymes in mouse models of inflammatory disorders, we report here the chromosomal mapping of the genes for the constitutive and regulated PGS/COX enzymes. We will refer to the constitutive enzyme as Pgs-1 and the inducible enzyme as Pgs-2. 14 refs., 1 tab.

  7. Expression of prostaglandin E synthases in the bovine oviduct.

    PubMed

    Gauvreau, D; Moisan, V; Roy, M; Fortier, M A; Bilodeau, J-F

    2010-01-01

    The oviduct is a specialized organ responsible for the storage and the transport of male and female gametes. It also provides an optimal environment for final gamete maturation, fertilization, and early embryo development. Prostaglandin (PG) E(2) is involved in many female reproductive functions, including ovulation, fertilization, implantation, and parturition. However, the control of its synthesis in the oviduct is not fully understood. Cyclooxygenases (COXs) are involved in the first step of the transformation of arachidonic acid to PGH(2.) The prostaglandin E synthases (PGESs) constitute a family of enzymes that catalyze the conversion of PGH(2) to PGE(2), the terminal step in the formation of this bioactive prostaglandin. Quantitative real-time PCR was used to determine the expression of COX-1, COX-2, microsomal prostaglandin E synthase-1 (mPGES-1), microsomal prostaglandin E synthase-2 (mPGES-2), and cytosolic prostaglandin E synthase (cPGES) mRNA in various sections of the oviduct, both ipsilateral and contralateral (to the ovary on which ovulation occurred) at various stages of the estrous cycle. Furthermore, protein expression and localization of cPGES, mPGES-1, and mPGES-2 were determined by Western blot and immunohistochemistry. All three PGESs were detected at both mRNA and protein levels in the oviduct. These PGESs were mostly concentrated in the oviductal epithelial layer and primarily expressed in the ampulla section of the oviduct and to a lesser extent in the isthmus and the isthmic-ampullary junction. The mPGES-1 protein was highly expressed in the contralateral oviduct, which contrasted with mPGES-2 mostly expressed in the ipsilateral oviduct. This is apparently the first report documenting that the three PGESs involved in PGE(2) production were present in the Bos taurus oviduct. PMID:19875162

  8. Prostaglandins, H2-receptor antagonists and peptic ulcer disease.

    PubMed

    Bright-Asare, P; Habte, T; Yirgou, B; Benjamin, J

    1988-01-01

    Peptic ulcer develops when offensive factors overwhelm defensive processes in the gastroduodenal mucosa. Offensive factors include NSAIDs, hydrochloric acid-peptic activity, bile reflux, and some products of the lipoxygenase pathway such as leukotriene B4; whereas defensive processes are largely mediated by prostaglandins through poorly understood mechanisms uniformly termed cytoprotection. Cytoprotection, a physiological process working through the products of arachidonic acid metabolism, may result from the net effect of the protective actions of prostaglandins versus the damaging actions of leukotrienes. Some prostaglandins also have antisecretory effects. Therefore the peptic ulcer healing effects of prostaglandin analogues, all of which have significant antisecretory activity, may be more due to their antisecretory effects than primarily to their effects on mucosal defences. Certain drug-induced gastroduodenal lesions, e.g. NSAID-induced ulcers, which are often unresponsive to H2-receptor antagonists, have been healed and their recurrence prevented by the use of PGE1 and PGE2 analogues. All the prostaglandin analogues investigated to date in humans have the potential for inducing abortion, an important side effect which may limit their worldwide use. The optimal prostaglandin analogue for ulcer healing should not induce abortion and should be potently cytoprotective. The predominant damaging agent in the development of peptic ulcer disease is gastric hydrochloric acid. Thus, the worldwide established efficacy and safety of H2-receptor antagonists such as cimetidine, ranitidine, famotidine and most recently of roxatidine acetate suggest that these agents have become the standard by which other forms of anti-ulcer therapy should be judged. PMID:2905237

  9. Suppression of Alzheimer-Associated Inflammation by Microglial Prostaglandin-E2 EP4 Receptor Signaling

    PubMed Central

    Woodling, Nathaniel S.; Wang, Qian; Priyam, Prachi G.; Larkin, Paul; Shi, Ju; Johansson, Jenny U.; Zagol-Ikapitte, Irene; Boutaud, Olivier

    2014-01-01

    A persistent and nonresolving inflammatory response to accumulating Aβ peptide species is a cardinal feature in the development of Alzheimer's disease (AD). In response to accumulating Aβ peptide species, microglia, the innate immune cells of the brain, generate a toxic inflammatory response that accelerates synaptic and neuronal injury. Many proinflammatory signaling pathways are linked to progression of neurodegeneration. However, endogenous anti-inflammatory pathways capable of suppressing Aβ-induced inflammation represent a relatively unexplored area. Here we report that signaling through the prostaglandin-E2 (PGE2) EP4 receptor potently suppresses microglial inflammatory responses to Aβ42 peptides. In cultured microglial cells, EP4 stimulation attenuated levels of Aβ42-induced inflammatory factors and potentiated phagocytosis of Aβ42. Microarray analysis demonstrated that EP4 stimulation broadly opposed Aβ42-driven gene expression changes in microglia, with enrichment for targets of IRF1, IRF7, and NF-κB transcription factors. In vivo, conditional deletion of microglial EP4 in APPSwe-PS1ΔE9 (APP-PS1) mice conversely increased inflammatory gene expression, oxidative protein modification, and Aβ deposition in brain at early stages of pathology, but not at later stages, suggesting an early anti-inflammatory function of microglial EP4 signaling in the APP-PS1 model. Finally, EP4 receptor levels decreased significantly in human cortex with progression from normal to AD states, suggesting that early loss of this beneficial signaling system in preclinical AD development may contribute to subsequent progression of pathology. PMID:24760848

  10. [Receptors involved in the mechanism of action of topical prostaglandines].

    PubMed

    Neacsu, Alina Mihaela

    2009-01-01

    Hypotensive effect to prostaglandins analogs (latanoprost, travoprost, tafluprost) means to increase uveoscleral outflow by action to FP receptors who generated extracellular matrix changes and intermuscular spaces changes. Syntetic prostamides analogs (bimatoprost) have a particulary action with a receptors most and intensive studied. The bimatoprost effect is the consequences to preferated stimulations on the specific receptors who have action only the tissue with prostaglandins activity is important to specify what the bimatoprost have dual effect: to uveoscleral outflow and classic outflow by increase hidraulic conductivity. PMID:19697832

  11. Characterization of the interaction between the prostaglandin D2 DP1 receptor and the intracellular L-prostaglandin D synthase.

    PubMed

    Binda, Chantal; Parent, Jean-Luc

    2015-01-01

    Identification of G protein-coupled receptor (GPCR)-interacting proteins is an intense subject of current research. However, confirmation and characterization of identified interactions can be difficult with GPCRs, especially at the endogenous level. Here, we describe how we characterized the interaction between the prostaglandin D2 DP1 receptor and the intracellular L-type prostaglandin D synthase by in vitro pull-down assays using purified recombinant GST- and His-tagged proteins, by co-immunoprecipitation of overexpressed Flag- and HA-tagged proteins, and by co-immunoprecipitation of endogenous proteins. PMID:25304348

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

    PubMed Central

    2010-01-01

    Background The pathogenesis for colorectal cancer remains unresolved. A growing body of evidence suggests a direct correlation between cyclooxygenase enzyme expression, prostaglandin E2 metabolism and neoplastic development. Thus further understanding of the regulation of epithelial functions by prostaglandin E2 is needed. We hypothesized that patients with colonic neoplasia have altered colonic epithelial ion transport and express functionally different prostanoid receptor levels in this respect. Methods Patients referred for colonoscopy were included and grouped into patients with and without colorectal neoplasia. Patients without endoscopic findings of neoplasia served as controls. Biopsy specimens were obtained from normally appearing mucosa in the sigmoid part of colon. Biopsies were mounted in miniaturized modified Ussing air-suction chambers. Indomethacin (10 μM), various stimulators and inhibitors of prostanoid receptors and ion transport were subsequently added to the chamber solutions. Electrogenic ion transport parameters (short circuit current and slope conductance) were recorded. Tissue pathology and tissue damage before and after experiments was assessed by histology. Results Baseline short circuit current and slope conductance did not differ between the two groups. Patients with neoplasia were significantly more sensitive to indomethacin with a decrease in short circuit current of 15.1 ± 2.6 μA·cm-2 compared to controls, who showed a decrease of 10.5 ± 2.1 μA·cm-2 (p = 0.027). Stimulation or inhibition with theophylline, ouabain, bumetanide, forskolin or the EP receptor agonists prostaglandin E2, butaprost, sulprostone and prostaglandin E1 (OH) did not differ significantly between the two groups. Histology was with normal findings in both groups. Conclusions Epithelial electrogenic transport is more sensitive to indomethacin in normal colonic mucosa from patients with previous or present colorectal neoplasia compared to colonic mucosa from

  13. Ketoprofen S(+) enantiomer inhibits prostaglandin production and cell growth in 3T6 fibroblast cultures.

    PubMed

    Sánchez, T; Moreno, J J

    1999-04-01

    The ketoprofen S(+) enantiomer inhibits with great stereoselectivity both prostaglandin H synthase isoenzymes. Thus, the biological effects of ketoprofen on inflammation are due almost entirely to the S(+) isomer. Here, we report that the S(+) enantiomer, at doses that inhibit prostaglandin synthesis, is effective in reducing DNA synthesis and 3T6 fibroblast growth. Our data suggest that prostaglandins are involved in the control of 3T6 fibroblast growth and that the effect of the ketoprofen S(+) enantiomer on 3T6 proliferation is correlated with its effects on prostaglandin H synthase and prostaglandin production. PMID:10323281

  14. Reducing prostaglandin E2 production to raise cancer immunogenicity

    PubMed Central

    Zelenay, Santiago; Reis e Sousa, Caetano

    2016-01-01

    ABSTRACT Cyclooxygenases (COX), commonly upregulated in numerous cancers, generate prostaglandin E2 (PGE2), which has been implicated in key aspects of malignant growth including proliferation, invasion and angiogenesis. Recently, we showed that production of PGE2 by cancer cells dominantly enables progressive tumor growth via immune escape and that cyclooxygenase inhibitors synergize with immunotherapy to enhance tumor eradication.

  15. Reducing prostaglandin E2 production to raise cancer immunogenicity.

    PubMed

    Zelenay, Santiago; Reis E Sousa, Caetano

    2016-05-01

    Cyclooxygenases (COX), commonly upregulated in numerous cancers, generate prostaglandin E2 (PGE2), which has been implicated in key aspects of malignant growth including proliferation, invasion and angiogenesis. Recently, we showed that production of PGE2 by cancer cells dominantly enables progressive tumor growth via immune escape and that cyclooxygenase inhibitors synergize with immunotherapy to enhance tumor eradication. PMID:27467936

  16. [Medical treatments and practices. What should be done when a prostaglandin proves ineffective?].

    PubMed

    Nordmann, J-P

    2005-06-01

    Prostaglandin analogs are very frequently used as first-line therapy in the treatment of glaucoma. In some cases, they may be ineffective or insufficient or they may induce side effects. The absence of an ocular pressure-lowering effect of a prostaglandin is in general a class effect. Thus a switch to another prostaglandin will probably not be more effective. In such cases, it may be better to use another therapeutic class. On the other hand, the side effects of prostaglandin are more often directly related to the chemical structure of the drug used and may not occur with another prostaglandin. Consequently, considering the dramatic effect of prostaglandin on ocular pressure compared to other drugs, when one prostaglandin causes side effects, it may be useful to try another one before changing the drug family. PMID:16208240

  17. Prostaglandin control of renal circulation in the unanesthetized dog and baboon

    NASA Technical Reports Server (NTRS)

    Swain, J. A.; Vatner, S. F.; Heyndrickx, G. R.; Boettcher, D. H.

    1975-01-01

    Effects of indomethacin and meclofenamate, inhibitors of prostaglandin synthesis, were evaluated in the regulation of renal blood flow in conscious and anesthetized dogs and in tranquilized baboons, instrumented with arterial pressure catheters and renal blood flow probes. Indomethacin, 10 mg/kg, did not alter renal blood flow or resistance significantly in the conscious dog. In the anesthetized dog, however, indomethacin caused a reduction in renal blood flow and an elevation of renal vascular resistance. Meclofenamate, 4 mg/kg, reduced renal flow and increased renal vascular resistance in conscious dogs. In conscious dogs and tranquilized primates, indomethacin and meclofenamate reduced the reactive hyperemia in the renal bed. Methoxamine and angiotensin II infused in graded doses induced significantly greater renal vasoconstriction in conscious dogs in the presence of indomethacin. Thus, in the conscious animal, prostaglandins appear to play only a minor part in the control of renal circulation at rest, but they are of greater importance in mediating the renal responses to reactive hyperemia and to vasoconstriction.

  18. Prostaglandin E2 differentially modulates the central control of eupnoea, sighs and gasping in mice

    PubMed Central

    Koch, Henner; Caughie, Cali; Elsen, Frank P; Doi, Atsushi; Garcia, Alfredo J; Zanella, Sebastien; Ramirez, Jan-Marino

    2015-01-01

    Prostaglandins are important regulators of autonomic functions in the mammalian organism. Here we demonstrate in vivo that prostaglandin E2 (PGE2) can differentially increase the frequency of eupnoea (normal breathing) and sighs (augmented breaths) when injected into the preBötzinger complex (preBötC), a medullary area that is critical for breathing. Low concentrations of PGE2 (100–300 nm) increased the sigh frequency, while higher concentrations (1–2 μm) were required to increase the eupnoeic frequency. The concentration-dependent effects were similarly observed in the isolated preBötC. This in vitro preparation also revealed that riluzole, a blocker of the persistent sodium current (INap), abolished the modulatory effect on sighs, while flufenamic acid, an antagonist for the calcium-activated non-selective cation conductance (ICAN) abolished the effect of PGE2 on fictive eupnoea at higher concentrations. At the cellular level PGE2 significantly increased the amplitude and frequency of intrinsic bursting in inspiratory neurons. By contrast PGE2 affected neither excitatory nor inhibitory synaptic transmission. We conclude that PGE2 differentially modulates sigh, gasping and eupnoeic activity by differentially increasing INap and ICAN currents in preBötC neurons. PMID:25556802

  19. Prostaglandin D2 inhibits wound-induced hair follicle neogenesis through the receptor, Gpr44.

    PubMed

    Nelson, Amanda M; Loy, Dorothy E; Lawson, John A; Katseff, Adiya S; Fitzgerald, Garret A; Garza, Luis A

    2013-04-01

    Prostaglandins (PGs) are key inflammatory mediators involved in wound healing and regulating hair growth; however, their role in skin regeneration after injury is unknown. Using wound-induced hair follicle neogenesis (WIHN) as a marker of skin regeneration, we hypothesized that PGD2 decreases follicle neogenesis. PGE2 and PGD2 were elevated early and late, respectively, during wound healing. The levels of WIHN, lipocalin-type prostaglandin D2 synthase (Ptgds), and its product PGD2 each varied significantly among background strains of mice after wounding, and all correlated such that the highest Ptgds and PGD2 levels were associated with the lowest amount of regeneration. In addition, an alternatively spliced transcript variant of Ptgds missing exon 3 correlated with high regeneration in mice. Exogenous application of PGD2 decreased WIHN in wild-type mice, and PGD2 receptor Gpr44-null mice showed increased WIHN compared with strain-matched control mice. Furthermore, Gpr44-null mice were resistant to PGD2-induced inhibition of follicle neogenesis. In all, these findings demonstrate that PGD2 inhibits hair follicle regeneration through the Gpr44 receptor and imply that inhibition of PGD2 production or Gpr44 signaling will promote skin regeneration. PMID:23190891

  20. Prostaglandin D2 inhibits wound-induced hair follicle neogenesis through the receptor, Gpr44

    PubMed Central

    Nelson, Amanda M.; Loy, Dorothy E.; Lawson, John A.; Katseff, Adiya S.; FitzGerald, Garret A.; Garza, Luis A.

    2012-01-01

    Prostaglandins (PGs) are key inflammatory mediators involved in wound healing and regulating hair growth; however, their role in skin regeneration after injury is unknown. Using wound-induced hair follicle neogenesis (WIHN) as a marker of skin regeneration, we hypothesized that PGD2 decreases follicle neogenesis. PGE2 and PGD2 were elevated early and late respectively during wound healing. The levels of WIHN, lipocalin-type prostaglandin D2 synthase (Ptgds) and its product PGD2 each varied significantly among background strains of mice after wounding and all correlated such that the highest Ptgds and PGD2 levels were associated with the lowest amount of regeneration. Additionally, an alternatively spliced transcript variant of Ptgds missing exon 3 correlated with high regeneration in mice. Exogenous application of PGD2 decreased WIHN in wild type mice and PGD2 receptor Gpr44 null mice showed increased WIHN compared to strain-matched control mice. Furthermore, Gpr44 null mice were resistant to PGD2-induced inhibition of follicle neogenesis. In all, these findings demonstrate that PGD2 inhibits hair follicle regeneration through the Gpr44 receptor and imply that inhibition of PGD2 production or Gpr44 signaling will promote skin regeneration. PMID:23190891

  1. Long-term assessment of prostaglandin analogs and timolol fixed combinations vs prostaglandin analogs monotherapy

    PubMed Central

    Liu, Ai-Wei; Gan, Lin-Yang; Yao, Xiang; Zhou, Jian

    2016-01-01

    AIM To draw a Meta-analysis over the comparison of the intraocular pressure (IOP)-lowering efficacy and safety between the commonly used fixed-combinations of prostaglandin analogs and 0.5% timolol with prostaglandin analogs (PGAs) monotherapy. METHODS After searching the published reports from MEDLINE, EMBASE, the Cochrane Library, all randomized controlled clinical trials (RCTs) comparing the fixed combination of PGAs/timolol therapy (FCs) and PGAs monotherapy with treatment duration at least 6mo were included. The efficacy outcomes were mean diurnal IOP, percentage of participants whose IOP were lower than 18 mm Hg, incidence of visual field change, while the safety outcomes included corneal side effects, hyperemia and eye irritation. The analysis was carried out in RevMan version 5.3 software. RESULTS After six-month medical intervention, the mean diurnal IOP of FCs was lower than PGAs (MD -1.14, 95% CI -1.82 to -0.46, P=0.001); the percentage of target IOP achieving between FCs and PGAs showed no significant difference (RR 1.18, 95% CI 0.97 to 1.43, P=0.10). No statistically significant differences of the incidence of hyperemia (RR 0.67, 95% CI 0.45 to 1.01, P=0.06) and eye irritation (RR 1.20, 95% CI 0.95 to 1.51, P=0.12) between the FCs and PGAs monotherapy were detected. Only one research involved in corneal events, result of this trial revealed no difference between two intervention groups regarding corneal effects (central endothelial cell density, MD -0.20, 95% CI -0.72 to 0.32, P=0.45; central corneal thickness, MD -0.01, 95% CI -0.02 to 0.00, P=0.23). The evaluation of visual field change was not performed due to the limited duration of the trials included in this Meta-analysis. CONCLUSION The long-term efficacy of the FCs overweighed the PGAs monotherapy in lowering IOP, but in the incidence of hyperemia and eye irritation syndromes, the differences are not statically significant. More RCTs with detailed and authentic data over the assessments of

  2. The expression of prostaglandin-E2 and its receptor in the oviduct of Chinese brown frog (Rana dybowskii).

    PubMed

    Hu, Ruiqi; Xi, Liqin; Cao, Qing; Yang, Rui; Liu, Yuning; Sheng, Xia; Han, Yingying; Yuan, Zhengrong; Guo, Yan; Weng, Qiang; Xu, Meiyu

    2016-07-01

    The Chinese brown frog (Rana dybowskii) has one special physiological phenomenon, which is that its oviduct expands prior to hibernation rather than in the breeding period. In this study, we investigated the immunolocalization and expression levels of prostaglandin-E2 (PGE2), cyclooxygenase (COX)-1 and COX-2, as well as one of its receptor subtypes 4 (EP4) in the oviduct of Rana dybowskii during the pre-hibernation and breeding period. PGE2, COX-1, COX-2 and EP4 have been observed in glandular and epithelial cells in the breeding period, whereas only in the epithelial cells during the pre-hibernation. Consistently, the protein levels of COX-2 and EP4 were higher in the pre-hibernation as compared to the breeding period, but the diversity of COX-1 was not obvious. In addition, oviductal PGE2 concentration was also significantly higher in the pre-hibernation. These results suggested that prostaglandin-E2 may play an important autocrine or paracrine role in oviductal cell proliferation and differentiation of Rana dybowskii during pre-hibernation. PMID:27246901

  3. Prostaglandin uptake and metabolism by the perfused rat liver

    PubMed Central

    Dawson, W.; Jessup, Sheila J.; McDonald-Gibson, Wendy; Ramwell, P. W.; Shaw, Jane E.

    1970-01-01

    1. The prostaglandins are C20 unsaturated fatty acids which exhibit diverse physiological effects of short duration. We have investigated the speed of removal of PGE1 and PGF1α from the circulating blood and their subsequent metabolism by the isolated perfused rat liver. 2. Following either a single injection of radiolabelled PGE1 or PGF1α into the hepatic artery or portal vein, or recirculation of prostaglandins through the liver for 2·5 h, the distribution of radioactivity within extracts of bile, blood and liver was determined. The nature of the radioactive products of meta-bolism was inferred by comparison of the distribution of radioactivity after injecting carbon and tritium labelled standards, and by thin-layer chromatography, gas-liquid chromatography, ultraviolet and bioassay analysis. 3. A single injection of 1-14C PGE1 indicated that the liver could efficiently remove 89-95% of circulating PGE1 on a single passage. Biliary excretion was excluded as a major route for elimination of unchanged PGE1, because only 0·3-0·8% of the injected radioactivity was detected in the bile. During recirculation of 1-14C PGE1, 11-19% of the injected radioactivity was detected as exchanged 14CO2. The radioactivity detected within liver was identified with further fragments resulting from decarboxylation of PGE1, which were incorporated into fatty acids and then phospholipids. 4. Studies with 5,6-3H PGE1, and comparison with the results obtained using 1-14C PGE1, revealed a 30-fold increase in the percentage of radioactivity excreted into the bile, suggesting that biliary excretion may be a major route for elimination of compounds smaller than C20 prostaglandin. Evidence that the cyclopentane ring was intact was inferred by formation of a PGB compound on treatment with alkali; similar biliary excretion of 9-3H PGF1α also occurred. In addition, the increased radioactivity detected within the liver (37%) and blood (43%) after a single injection of 5,6-3H PGE1 had the

  4. Oxysophocarpine Ameliorates Carrageenan-induced Inflammatory Pain via Inhibiting Expressions of Prostaglandin E2 and Cytokines in Mice.

    PubMed

    Yang, Yang; Li, Yu-Xiang; Wang, Hong-Ling; Jin, Shao-Ju; Zhou, Ru; Qiao, Hai-Qi; Du, Juan; Wu, Jing; Zhao, Cheng-Jun; Niu, Yang; Sun, Tao; Yu, Jian-Qiang

    2015-07-01

    Oxysophocarpine is an alkaloid extracted from Sophora alopecuroides. We investigated the analgesic effect of oxysophocarpine on carrageenan-induced inflammatory pain in mice, in order to explore its possible mechanisms. Mouse ear swelling tests and carrageenan-induced paw edema tests were used to investigate the effects of oxysophocarpine on inflammatory pain in mice. Morphological changes on inflamed paw sections were measured by hematoxylin-eosin staining. The mRNA and protein expression of extracellular signal-regulated kinase, phosphorylation of extracellular signal-regulated kinase 1/2, cyclooxygenase-2, tumor necrosis factor α, interleukin-1 beta, interleukin-6 and prostaglandin E2 were investigated by real-time quantitative polymerase chain reaction, immunohistochemistry, western-blot and enzyme-linked immunosorbent assay. In our results, oxysophocarpine shows a significant anti-inflammatory effect in the mouse ear swelling test. Oxysophocarpine also significantly reduced the paw edema volume and improved mechanical allodynia threshold value on carrageenan-induced inflammatory pain, as well as relieved paw tissues inflammatory damage and reduced the numbers of neutrophils in mice. Oxysophocarpine significantly suppressed over-expression of cyclooxygenase-2, tumor necrosis factor α, interleukin-1 beta, interleukin-6 and prostaglandin E2, and inhibited the over-phosphorylation of extracellular signal-regulated kinase 1/2. Based on these findings we propose that oxysophocarpine attenuates inflammatory pain by suppressing the levels of phosphorylation of extracellular signal-regulated kinase 1/2, cyclooxygenase-2, prostaglandin E2, tumor necrosis factor α, interleukin-1 beta and interleukin-6. PMID:26132856

  5. Studies on the metabolism of prostaglandin D/sub 2/ in humans

    SciTech Connect

    Liston, T.E.

    1985-01-01

    Fifty ..mu..Ci of (/sup 3/H)-prostaglandin D/sub 2/ tracer (100 Ci/mMole) was infused intravenously into a normal human male volunteer. Seventy-five percent of the infused radioactivity was excreted into the urine within 5 hours. This urine was added to urine obtained from two mastocytosis patients with marked overproduction of prostaglandin D/sub 2/. Twenty-five radiolabelled prostaglandin D/sub 2/ urinary metabolites were chromatographically isolated and purified and subsequently identified by gas chromatography-mass spectrometry. Twenty-three of these metabolites, comprising 37% of the recovered radioactivity, had prostaglandin F-ring structures, and only 2 metabolites, comprising 2.7% of the recovered radioactivity retained the prostaglandin D-ring structure. The single most abundant metabolite identified was 9,11-dihydroxy-15-oxo-2,3,18,19-tetranorprost-5-energy-1,20-dioic acid which was isolated in a tricyclic form. Different isomeric forms of several prostaglandin F-ring metabolites were identified. To further investigate the metabolism of prostaglandin D/sub 2/, in vitro studies examining the metabolic transformation of prostaglandin D/sub 2/ by human liver were conducted. This study documents that prostaglandin D/sub 2/ is metabolized to PGF-ring metabolites in vivo in humans, and is converted to a structurally new prostaglandin, 9/sub ..cap alpha../, 11/sub ..beta../-PGF/sub 2/ in vitro by a cytosolic NADPH-dependent 11-Ketoreductase in the human liver.

  6. The mRNA expression of prostaglandin E receptors EP2 and EP4 and the changes in glycosaminoglycans in the sheep cervix during the estrous cycle.

    PubMed

    Kershaw-Young, C M; Khalid, M; McGowan, M R; Pitsillides, A A; Scaramuzzi, R J

    2009-07-15

    Transcervical artificial insemination in sheep is limited by the inability to completely penetrate the cervix with an inseminating pipette. Penetration is partially enhanced at estrus due to a degree of cervical relaxation, which is probably regulated by cervical prostaglandin synthesis and extracellular matrix remodeling. Prostaglandin E(2) acts via prostaglandin E receptors EP(1) to EP(4), and EP(2) and EP(4) stimulate smooth muscle relaxation and glycosaminoglycan synthesis. This study investigated the expression of EP(2) and EP(4) mRNA and glycosaminoglycans in the sheep cervix during the estrous cycle. Sheep cervices were collected prior to, during, and after the luteinizing hormone (LH) surge and during the luteal phase. The mRNA expression of EP(2) and EP(4) was determined by in situ hybridization, glycosaminoglycan composition was assessed by Alcian blue staining, and hyaluronan concentration was investigated by ELISA. The expression of EP(2) mRNA was greatest prior to the LH surge (P=0.02), although EP(2) and EP(4) were expressed throughout the estrous cycle. Hyaluronan was the predominant glycosaminoglycan, and hyaluronan content increased prior to the LH surge (P<0.05). Cervical EP(2) mRNA expression changed throughout the estrous cycle and was greatest prior to the LH surge. We propose that prostaglandin E(2) binds to EP(2) and EP(4) stimulating hyaluronan synthesis, which may cause remodeling of the cervical extracellular matrix, culminating in cervical relaxation. PMID:19359033

  7. Neurogenic contractions in intraocular porcine ciliary arteries are mediated by α₂-adrenoceptors and NPY₁ receptors and are inhibited by prostaglandin E₂ acting on prejunctional EP₄ receptors.

    PubMed

    Kringelholt, Sidse; Simonsen, Ulf; Bek, Toke

    2013-02-01

    Prostaglandin analogues and adrenergic drugs are used to reduce the intraocular pressure in glaucoma, which may partly be due to an effect on the tone of the intraocular arteries supplying the ciliary body. The aim of the present study was to investigate the interaction between prostaglandins and autonomic nervous activity induced by electrical stimulation of the tone in these ciliary vessels. The intraocular part of porcine ciliary arteries were isolated and mounted in a microvascular myograph for isometric tension recordings, and the effect of prostaglandin E(2) on electrically induced contractions was studied in the presence of selective EP receptor antagonists. PGE(2) induced concentration-dependent inhibition of electrically induced contractions of intraocular ciliary arteries which depended on the presence of the vascular endothelium. The effect of PGE(2) was blocked by an EP(4) receptor antagonist but not by an EP(1) receptor antagonist. The neurogenic contractions were partially inhibited by an α(2)-adrenoceptor antagonist and totally inhibited by a NPY(1) receptor antagonist. The effect of these antagonists was similar when contraction was induced by noradrenaline and NPY. Neurogenic contractions in intraocular porcine arteries are mediated by α(2)-adrenoceptors and NPY(1) receptors and can be inhibited by PGE(2) acting on prejunctional EP(4) receptors. This contributes to a further understanding of the role of the autonomic nervous system and prostaglandins for regulating blood flow to the anterior segment of the eye. PMID:23178872

  8. Prostaglandin E₂ constrains systemic inflammation through an innate lymphoid cell-IL-22 axis.

    PubMed

    Duffin, Rodger; O'Connor, Richard A; Crittenden, Siobhan; Forster, Thorsten; Yu, Cunjing; Zheng, Xiaozhong; Smyth, Danielle; Robb, Calum T; Rossi, Fiona; Skouras, Christos; Tang, Shaohui; Richards, James; Pellicoro, Antonella; Weller, Richard B; Breyer, Richard M; Mole, Damian J; Iredale, John P; Anderton, Stephen M; Narumiya, Shuh; Maizels, Rick M; Ghazal, Peter; Howie, Sarah E; Rossi, Adriano G; Yao, Chengcan

    2016-03-18

    Systemic inflammation, which results from the massive release of proinflammatory molecules into the circulatory system, is a major risk factor for severe illness, but the precise mechanisms underlying its control are not fully understood. We observed that prostaglandin E2 (PGE2), through its receptor EP4, is down-regulated in human systemic inflammatory disease. Mice with reduced PGE2 synthesis develop systemic inflammation, associated with translocation of gut bacteria, which can be prevented by treatment with EP4 agonists. Mechanistically, we demonstrate that PGE2-EP4 signaling acts directly on type 3 innate lymphoid cells (ILCs), promoting their homeostasis and driving them to produce interleukin-22 (IL-22). Disruption of the ILC-IL-22 axis impairs PGE2-mediated inhibition of systemic inflammation. Hence, the ILC-IL-22 axis is essential in protecting against gut barrier dysfunction, enabling PGE2-EP4 signaling to impede systemic inflammation. PMID:26989254

  9. Prostaglandin-secreting cells: a portable first aid kit for tissue repair

    PubMed Central

    Rakoff-Nahoum, Seth; Medzhitov, Ruslan

    2007-01-01

    After intestinal injury, both the number and type of intestinal epithelial cells must be restored. Intestinal stem cells, located at the base of the intestinal crypt, repopulate the depleted crypt in a process known as compensatory proliferation. In this issue of the JCI, Brown et al. describe a new mechanism by which this process is regulated (see the related article beginning on page 258). Surprisingly, they find that a subset of stromal cells present within the intestinal tissue and expressing the proliferative factor prostaglandin-endoperoxidase synthase 2 (Ptgs2) is repositioned next to the intestinal stem cell compartment where local production of PGE2 controls injury-induced epithelial cell proliferation. PMID:17200710

  10. Behavioural and autonomic induction of prostaglandin E-1 fever in squirrel monkeys.

    PubMed Central

    Crawshaw, L I; Stitt, J T

    1975-01-01

    1. Prostaglandins E1 (PGE1) was injected into the preoptic/anterior hypothalamic (PO/AH) area of the squirrel monkey. 2. Increases in rectal temperature (Tre) produced by PGE1 injections of 20 ng to 500 ng were dose-dependent. 3. When ambient temperature (Ta) was below the thermoneutral zone, increases in Tre were produced entirely by increases in metabolic rate. With Ta at the upper end of the thermoneutral zone, increases in Tre were produced by vasoconstriction in addition to lesser increases in metabolic rate. 4. During sessions of behavioural temperature regulation, PGE1 injections were followed by the selection of a higher Ta, increased skin temperature and subsequent increases in Tre. 5. PGE1 injections produce dose-dependent increases in Tre which are similar regardless of ambient temperature or whether behavioural or autonomic means are utilized to raise the heat content of the body. PMID:804544

  11. Eicosanoids Derived From Arachidonic Acid and Their Family Prostaglandins and Cyclooxygenase in Psychiatric Disorders

    PubMed Central

    Yui, Kunio; Imataka, George; Nakamura, Hiroyuki; Ohara, Naoki; Naito, Yukiko

    2015-01-01

    Arachidonic acid (AA)-derived lipid mediators are called eicosanoids. Eicosanoids have emerged as key regulators of a wide variety of physiological responses and pathological processes, and control important cellular processes. AA can be converted into biologically active compounds by metabolism by cyclooxygenases (COX). Beneficial effect of COX-2 inhibitor celecoxib add-on therapy has been reported in early stage of schizophrenia. Moreover, add-on treatment of celecoxib attenuated refractory depression and bipolar depression. Further, the COX/prostaglandin E pathway play an important role in synaptic plasticity and may be included in pathophysiology in autism spectrum disorders (ASD). In this regard, plasma transferrin, which is an iron mediator related to eicosanoid signaling, may be related to social impairment of ASD. COX-2 is typically induced by inflammatory stimuli in the majority of tissues, and the only isoform responsible for propagating the inflammatory response. Thus, COX-2 inhibitors considered as the best target for Alzheimer’s disease. PMID:26521945

  12. Cytoprotective effect of prostaglandin E2 in irradiated rat ileum

    SciTech Connect

    Tomas-de la Vega, J.E.; Banner, B.F.; Hubbard, M.; Boston, D.L.; Thomas, C.W.; Straus, A.K.; Roseman, D.L.

    1984-01-01

    Radiation injury to the gastrointestinal tract is an infrequent but major clinical problem. Results of previous studies have shown that prostaglandins provide cytoprotection of the gastrointestinal mucosa against a variety of noxious agents, although, prior to this study, the protection against radiation exposure had not been documented. Exteriorized segment of Sprague-Dawley rat ileum was radiated with 10 and 15 Gy (/sup 137/Cs). One group of rats was pretreated with prostaglandin E2 one hour before and 24 hours after radiation injury. The rats were sacrificed three and five days following radiation injury. Morphometric measurement of mucosal thickness, villous height, crypt of Lieberkuehn height and number of mitoses per square millimeter swath of tissue were analyzed. Also, /sup 125/IUdR and /sup 3/HTdR were injected in a group of rats radiated with 15 Gy (/sup 137/Cs). /sup 125/IUdR counts per minute per milligram of dry weight and /sup 3/HTdR labeled cells were counted and analyzed. The morphometric measurements and radioactive labeled tissue counts suggest that prostaglandin E2 has a cytoprotective effect upon irradiated rat ileum. Speculations about the possible mechanism and usefulness of this observation are included.

  13. Evaluation of the role of prostaglandins E and F in acalculous gallbladder disease

    SciTech Connect

    Deshpande, Y.G.; Kaminski, D.L.; Thomas, L.

    1986-03-01

    Prostaglandins have been shown to play a role in gallbladder disease. This study was performed to evaluate prostaglandin E and F production by human gallbladder mucosal cells and muscle tissue from patients undergoing cholecystectomy for acalculous gallbladder disease. These results were compared to values produced by gall bladders removed from patients with no known gallbladder disease. Five patient underwent cholecystectomy for acute and five for chronic acalculous cholecystitis. Gallbladder mucosal cells were separated from muscle wall by submucosal injection of EDTA and shaking in tissue culture media. Prostaglandin levels were measured in mucosal cell and muscle tissue homogenate by radioimmunoassay (ng/mg homogenate protein). Homogenate prostaglandin E concentrations were significantly increased in mucosa and muscle tissue in gall bladders from patients with acute acalculous cholecystitis. Chronic acalculous gallbladder disease was not associated with changes in prostaglandin formation when compared to values produced by gall bladders from asymptomatic patients. Acute acalculous cholecystitis may be a prostaglandin mediated disorder.

  14. Attenuation of Ischemic Liver Injury by Prostaglandin E1 Analogue, Misoprostol, and Prostaglandin I2 Analogue, OP-41483

    PubMed Central

    Totsuka, Eishi; Todo, Satoru; Zhu, Yue; Ishizaki, Naoki; Kawashima, Yoshiyuki; Jin, Maeng Bong; Urakami, Atsushi; Shimamura, Tsuyoshi; Starzl, Thomas E

    2010-01-01

    Background Prostaglandin has been reported to have protective effects against liver injury. Use of this agent in clinical settings, however, is limited because of drug-related side effects. This study investigated whether misoprostol, prostaglandin E1 analogue, and OP-41483, prostaglandin I2 analogue, which have fewer adverse effects with a longer half-life, attenuate ischemic liver damage. Study Design Thirty beagle dogs underwent 2 hours of hepatic vascular exclusion using venovenous bypass. Misoprostol was administered intravenously for 30 minutes before ischemia and for 3 hours after reperfusion. OP-41483 was administered intraportally for 30 minutes before ischemia (2 μg/kg/min) and for 3 hours after reperfusion (0.5 μg/kg/min). Animals were divided into five groups: untreated control group (n = 10); high-dose misoprostol (total 100 μg/kg) group (MP-H, n = 5); middle-dose misoprostol (50 μg/kg) group (MP-M, n = 5); low-dose misoprostol (25 μg/kg) group (MP-L, n = 5); and OP-41483 group (OP, n = 5). Animal survival, hepatic tissue blood flow (HTBF), liver function, and histology were analyzed. Results Two-week animal survival rates were 30% in control, 60% in MP-H, 100% in MP-M, 80% in MP-L, and 100% in OP. The treatments with prostaglandin analogues improved HTBF, and attenuated liver enzyme release, adenine nucleotrides degradation, and histologic abnormalities. In contrast to the MP-H animals that exhibited unstable cardiovascular systems, the MP-M, MP-L, and OP animals experienced only transient hypotension. Conclusions These results indicate that misoprostol and OP-41483 prevent ischemic liver damage, although careful dose adjustment of misoprostol is required to obtain the best protection with minimal side effects. PMID:9740185

  15. Mechanical stimulation of skeletal muscle cells mitigates glucocorticoid-induced decreases in prostaglandin production and prostaglandin synthase activity

    NASA Technical Reports Server (NTRS)

    Chromiak, J. A.; Vandenburgh, H. H.

    1994-01-01

    The glucocorticoid dexamethasone (Dex) induces a decline in protein synthesis and protein content in tissue cultured, avian skeletal muscle cells, and this atrophy is attenuated by repetitive mechanical stretch. Since the prostaglandin synthesis inhibitor indomethacin mitigated this stretch attenuation of muscle atrophy, the effects of Dex and mechanical stretch on prostaglandin production and prostaglandin H synthase (PGHS) activity were examined. In static cultures, 10(-8) M Dex reduced PGF2 alpha production 55-65% and PGE2 production 84-90% after 24-72 h of incubation. Repetitive 10% stretch-relaxations of non-Dex-treated cultures increased PGF2 alpha efflux 41% at 24 h and 276% at 72 h, and increased PGE2 production 51% at 24 h and 236% at 72 h. Mechanical stimulation of Dex-treated cultures increased PGF2 alpha production 162% after 24 h, returning PGF2 alpha efflux to the level of non-Dex-treated cultures. At 72 h, stretch increased PGF2 alpha efflux 65% in Dex-treated cultures. Mechanical stimulation of Dex-treated cultures also increased PGE2 production at 24 h, but not at 72 h. Dex reduced PGHS activity in the muscle cultures by 70% after 8-24 h of incubation, and mechanical stimulation of the Dex-treated cultures increased PGHS activity by 98% after 24 h. Repetitive mechanical stimulation attenuates the catabolic effects of Dex on cultured skeletal muscle cells in part by mitigating the Dex-induced declines in PGHS activity and prostaglandin production.

  16. The use of prostaglandins and their analogues for abortion.

    PubMed

    Bygdeman, M

    1984-12-01

    In general, termination of second trimester pregnancy is associated with three to five times higher morbidity and mortality risks than termination during the first trimester. The procedures mainly used are extra- or intra-amniotic administration of solutions such as hypertonic saline, ethacridine lactate, PGF2 alpha and PGE2. In comparison with these procedures, the use of prostaglandin analogues may offer important advantages, the most important one being the possibility of using non-invasive routes of administration. The continuous development of new analogues has now resulted in compounds that are highly effective in stimulating uterine contractility and are associated with a low frequency of side-effects; these compounds are suitable for both vaginal and intramuscular administration and are applicable for termination of pregnancy during both the early and late parts of the second trimester. The most widely used method for termination of first trimester pregnancy is vacuum aspiration. It is a highly effective procedure and the overall complication rate is low. One problem with vacuum aspiration is the mechanical dilatation of the cervical canal which is necessary from at least the 8th week and onwards. Pretreatment with laminaria tents or with prostaglandin analogues eliminates or reduces the need for mechanical dilatation and significantly facilitates the procedure. Pretreatment with prostaglandin analogues also reduces the risk of both operative and postoperative complications. The prostaglandins also offer a possibility as a non-surgical procedure for termination of very early pregnancy. Both vaginal and intramuscular administration of the latest generation of PG analogues have been shown in several studies to be equally as effective as vacuum aspiration if the treatment is restricted to the first three weeks following the first missed menstrual period. Gastrointestinal side-effects are still a problem although of significantly less importance than if natural

  17. Prostaglandin E2 and Prostaglandin F2α Differentially Modulate Matrix Metabolism of Human Nucleus Pulposus Cells

    PubMed Central

    Vo, Nam V.; Sowa, Gwendolyn A.; Kang, James D.; Seidel, Christopher; Studer, Rebecca K.

    2016-01-01

    Prostaglandin (PG) actions on disc metabolism are unclear even though certain PGs are highly expressed by disc cells under inflammatory conditions and nonsteroidal anti-inflammatory drugs (NSAIDs) are frequently used to block PG production to treat back pain. Hence this study aimed to (1) quantify gene expression of arachidonic acid cascade components responsible for PG synthesis and (2) examine the effects of key PGs on disc matrix homeostasis. Microarray analysis revealed that inflammatory stress increases expression of synthases and receptors for prostaglandin E2 (PGE2) and prostaglandin F2α (PGF2α), resulting in elevated PGE2 and PGF2α production in conditioned media of disc cells. PGE2 diminished disc cell proteoglycan synthesis, in a dose-dependent manner. Semiquantitative RT-PCR revealed differential effects of PGE2 and PGF2α on disc cell expression of key matrix structural genes, aggrecan, versican, collagens type I and II. PGE2 and PGF2α also decreased message for the anabolic factor, IGF-1. PGE2 decreased mRNA expression for the anti-catabolic factor TIMP-1 while PGF2α increased mRNAs for catabolic factors MMP-1 and MMP-3. Thus, PGE2 and PGF2α may have an overall negative impact on disc matrix homeostasis, and the use of NSAIDs may impact disc metabolism as well as treat back pain. PMID:20839316

  18. Synthesis of prostaglandins by conjugate addition and alkylation of a directed enolate ion. 4,5-allenyl prostaglandins

    SciTech Connect

    Patterson, J.W. )

    1990-09-28

    Over the previous two decades many elegant syntheses of prostaglandins, which in more sophisticated forms, allow the stereospecific introduction of the various asymmetric carbons have been accomplished. However, among these approaches the cuprate addition/enolate alkylation of suitable cyclopentenone {sup 2} stands out because of brevity and convergence. The recent reports by Noyori{sup 3} and Corey{sup 4} and their colleagues have reduced to practice the conversion of 4-alkoxycyclopentenones to prostaglandin E{sub 2} (PGE{sub 2}) by conjugate addition of an organocopper derivative of the lower side chain followed by alkylation of the resulting carbanion with methyl 7-halohept-2-enoate. The subject of this paper is application of the Tardella tin enolate alkylation developed by Noyori to the synthesis of 4, 5-allenic prostaglandins, a pharmacologically important class of compounds. The authors results demonstrate that the tandem alkylation of an enone precursor with a cuprate reagent followed by alkylation of the corresponding tin enolate with bromide reagent is a viable synthetic method for 4,5-didehydro-PGE{sub 2}. Because the optically active forms of 1 and the vinyl iodide precursor of the PGE{sub 2} lower side chain have been employed to produce a single enantiomer of PGE{sub 2}, the extension of the methodology described here to the synthesis of single enantiomers of 4a awaits only the preparation of the separate enantiomers of allene 14.

  19. Co-oxidation of 2-bromohydroquinone by renal prostaglandin synthase. Modulation of prostaglandin synthesis by 2-bromohydroquinone and glutathione.

    PubMed

    Lau, S S; Monks, T J

    1987-01-01

    Homogenates from rat renal papillae, a rich source of the prostaglandin (PG) H synthase system (PHS), metabolized [14C]2-bromohydroquinone, in the presence of arachidonic acid, to products which are covalently bound to protein. The co-oxidation of 2-bromohydroquinone caused a concentration-dependent stimulation in 6-keto-PGF1 alpha, thromboxane B2, PGF2 alpha, PGE2, and PGD2 formation. Glutathione (1 mM) caused a decrease in prostaglandin formation and inhibited the arachidonic acid-supported covalent binding of [14C]2-bromohydroquinone with the concomitant formation of [14C]2-bromohydroquinone-glutathione conjugates, oxidized glutathione, and an increase in the recovery of [14C]2-bromohydroquinone. NADPH also inhibited [14C]2-bromohydroquinone covalent binding, probably by reduction of the semiquinone radical back to the hydroquinone. Indomethacin and aspirin, inhibitors of the cyclooxygenase component of PHS, and propylthiouracil and methimazole, inhibitors of the hydroperoxidase component of PHS, inhibited the arachidonic acid-supported covalent binding of [14C]2-bromohydroquinone by 94%, 52%, 78%, and 79% respectively. These data suggest that 1) renal PHS may play a role in activating the nephrotoxin, 2-bromohydroquinone, and that 2) xenobiotic metabolism and its subsequent effects on glutathione levels can modulate renal prostaglandin synthesis. PMID:2893705

  20. An evaluation of vulvomucosal injections of prostaglandins for induction of parturition in swine

    PubMed Central

    Friendship, Robert M.; Templeton, Catherine L.; Deckert, Anne E.

    1990-01-01

    Two trials were performed to evaluate the efficacy of prostaglandins administered via the vulvomucosal route at one-half the recommended dosage in comparison to prostaglandins injected intramuscularly (IM) at the standard dosage. In trial 1, sows on three commercial swine farms were given prostaglandin F2α at a dosage of 10 mg IM (n = 110) or 5 mg prostaglandin F2α using a vulvomucosal injection (n = 94). The numbers of sows farrowing within 36 h postinjection were 92 (84%) and 83 (88%), respectively. In trial 2, sows on four commercial swine operations were induced to farrow by means of one of three treatments: cloprostenol 175 μg IM (n = 71); cloprostenol 87.5 μg vulvomucosally (n = 57); or prostaglandin F2α 5 mg vulvomucosally (n = 96). The numbers of sows farrowing within 36 h postinduction were 69 (97%), 53 (93%), and 91 (94%), respectively. Vulvomucosal injections of prostaglandin F2α and cloprostenol at one-half the dosage appeared to be as effective as intramuscular injections of prostaglandin F2α and cloprostenol at the recommended level. There were fewer sows demonstrating restless behavior following the injection of lower dosages of prostaglandin F2α vulvomucosally, compared to sows given the recommended dosage of prostaglandin F2α IM. PMID:17423605

  1. [Novel treatment for prostate cancer targeting prostaglandins].

    PubMed

    Terada, Naoki; Inoue, Takahiro; Kamba, Tomomi; Ogawa, Osamu

    2014-12-01

    PGE2 is highly expressed in the prostate, associating with prostate cancer progression. Targeting downstream signaling pathways of PGE2 may represent an attractive new strategy for the treatment of prostate cancer. We have established a novel prostate cancer xenograft model, KUCaP-2. The expression of EP4, one of PGE2 receptors, was significantly up-regulated during the development of castration resistance. A specific EP4 antagonist, ONO-AE3-208, decelerated castration-resistant growth of KUCaP-2 tumors in vivo. Moreover, ONO-AE3-208 could in vitro inhibit the cell invasion and in vivo suppress the bone metastasis of prostate cancer cells. These results indicated that EP4 is a novel target for the treatment of metastatic castration resistant prostate cancer. PMID:25518348

  2. Minor changes in gene expression in the mouse preoptic hypothalamic region by inflammation-induced prostaglandin E2.

    PubMed

    Vasilache, A M; Kugelberg, U; Blomqvist, A; Nilsberth, C

    2013-07-01

    We investigated to what extent inflammation-induced prostaglandin E2 (PGE2 ) regulates gene expression in the central nervous system. Wild-type mice and mice with deletion of the gene encoding microsomal prostaglandin E synthase-1 (mPGES-1), which cannot produce inflammation-induced PGE2 , were subjected to peripheral injection of bacterial wall lipopolysaccharide (LPS) and killed after 5 h. The median and medial preoptic nuclei, which are rich in prostaglandin E receptors, were isolated by laser capture microdissection (LCM), and subjected to whole genome microarray analysis. Although the immune stimulus induced robust transcriptional changes in the brain, as seen by a quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR) on selected genes, only small PGE2 -dependent gene expression changes were observed in the gene array analysis and, for only two genes, a pronounced differential expression between LPS-treated wild-type and mPGES-1 knockout mice could be verified by qRT-PCR. These were Hspa1a and Hspa1b, encoding heat shock proteins, which showed a two- to three-fold higher expression in wild-type mice than in knockout mice after immune challenge. However, the induced expression of these genes was found to be secondary to increased body temperature because they were induced also by cage exchange stress, which did not elicit PGE2 synthesis, and thus were not induced per se by PGE2 -elicited transcriptional events. Our findings suggest that inflammation-induced PGE2 has little effect on gene expression in the preoptic region, and that centrally elicited disease symptoms, although PGE2 -dependent, occur as a result of regulation of neuronal excitability that is a consequence of intracellular, transcriptional-independent signalling cascades. Our findings also imply that the profound changes in gene expression in the brain that are elicited by peripheral inflammation occur independently of PGE2 via a yet unidentified mechanism. PMID:23631667

  3. A Neural Basis for Control of Cichlid Female Reproductive Behavior by Prostaglandin F2α.

    PubMed

    Juntti, Scott A; Hilliard, Austin T; Kent, Kai R; Kumar, Anusha; Nguyen, Andrew; Jimenez, Mariana A; Loveland, Jasmine L; Mourrain, Philippe; Fernald, Russell D

    2016-04-01

    In most species, females time reproduction to coincide with fertility. Thus, identifying factors that signal fertility to the brain can provide access to neural circuits that control sexual behaviors. In vertebrates, levels of key signaling molecules rise at the time of fertility to prime the brain for reproductive behavior [1-11], but how and where they regulate neural circuits is not known [12, 13]. Specifically, 17α,20β-dihydroxyprogesterone (DHP) and prostaglandin F2α (PGF2α) levels rise in teleost fish around the time of ovulation [10, 14, 15]. In an African cichlid fish, Astatotilapia burtoni, fertile females select a mate and perform a stereotyped spawning routine, offering quantifiable behavioral outputs of neural circuits. We show that, within minutes, PGF2α injection activates a naturalistic pattern of sexual behavior in female A. burtoni. We also identify cells in the brain that transduce the prostaglandin signal to mate and show that the gonadal steroid DHP modulates mRNA levels of the putative receptor for PGF2α (Ptgfr). We use CRISPR/Cas9 to generate the first targeted gene mutation in A. burtoni and show that Ptgfr is necessary for the initiation of sexual behavior, uncoupling sexual behavior from reproductive status. Our findings are consistent with a model in which PGF2α communicates fertility status via Ptgfr to circuits in the brain that drive female sexual behavior. Our targeted genome modification in a cichlid fish shows that dissection of gene function can reveal basic control mechanisms for behaviors in this large family of species with diverse and fascinating social systems [16, 17]. PMID:26996507

  4. Activation of prostaglandin E2-EP4 signaling reduces chemokine production in adipose tissue.

    PubMed

    Tang, Eva H C; Cai, Yin; Wong, Chi Kin; Rocha, Viviane Z; Sukhova, Galina K; Shimizu, Koichi; Xuan, Ge; Vanhoutte, Paul M; Libby, Peter; Xu, Aimin

    2015-02-01

    Inflammation of adipose tissue induces metabolic derangements associated with obesity. Thus, determining ways to control or inhibit inflammation in adipose tissue is of clinical interest. The present study tested the hypothesis that in mouse adipose tissue, endogenous prostaglandin E2 (PGE2) negatively regulates inflammation via activation of prostaglandin E receptor 4 (EP4). PGE2 (5-500 nM) attenuated lipopolysaccharide-induced mRNA and protein expression of chemokines, including interferon-γ-inducible protein 10 and macrophage-inflammatory protein-1α in mouse adipose tissue. A selective EP4 antagonist (L161,982) reversed, and two structurally different selective EP4 agonists [CAY10580 and CAY10598] mimicked these actions of PGE2. Adipose tissue derived from EP4-deficient mice did not display this response. These findings establish the involvement of EP4 receptors in this anti-inflammatory response. Experiments performed on adipose tissue from high-fat-fed mice demonstrated EP4-dependent attenuation of chemokine production during diet-induced obesity. The anti-inflammatory actions of EP4 became more important on a high-fat diet, in that EP4 activation suppressed a greater variety of chemokines. Furthermore, adipose tissue and systemic inflammation was enhanced in high-fat-fed EP4-deficient mice compared with wild-type littermates, and in high-fat-fed untreated C57BL/6 mice compared with mice treated with EP4 agonist. These findings provide in vivo evidence that PGE2-EP4 signaling limits inflammation. In conclusion, PGE2, via activation of EP4 receptors, functions as an endogenous anti-inflammatory mediator in mouse adipose tissue, and targeting EP4 may mitigate adipose tissue inflammation. PMID:25510249

  5. Prostaglandin synthesis inhibitors block alcohol-induced fetal hypoplasia.

    PubMed

    Pennington, S; Allen, Z; Runion, J; Farmer, P; Rowland, L; Kalmus, G

    1985-01-01

    Alcohol-induced growth retardation is a fetal effect consistently associated with maternal ethanol consumption. In humans, those infants whose mothers consume even a limited amount of ethanol during pregnancy have a significant incidence of growth inhibition. The molecular mechanism responsible for this growth deficiency is unknown, and prevention depends on maternal abstinence during pregnancy. The data reported here suggest that ethanol-mediated increases in tissue prostaglandin (PG) E levels (PGE1 plus PGE2) are correlated with the growth retardation. Further, simultaneous administration of PG synthesis inhibitors with the alcohol blocks the rise in tissue PG levels and protects against the alcohol-induced hypoplasia. PMID:3904508

  6. Reversal of the Transcriptome by Prostaglandin E2 during Myofibroblast Dedifferentiation.

    PubMed

    Wettlaufer, Scott H; Scott, Jacob P; McEachin, Richard C; Peters-Golden, Marc; Huang, Steven K

    2016-01-01

    Myofibroblasts, the major effector cells in pathologic fibrosis, derive from the differentiation of fibroblasts driven by mediators such as transforming growth factor-β1 (TGF-β1) and biomechanical signals. Although the myofibroblast has traditionally been considered a terminally differentiated cell, the lipid mediator prostaglandin E2 (PGE2) has been shown to not only prevent but also reverse myofibroblast differentiation, as characterized by the ability of PGE2 to diminish expression of collagen I and α-smooth muscle actin in established myofibroblasts. Here, we use microarrays to examine the extent of transcriptomic changes that occur during TGF-β1-induced differentiation and PGE2-induced dedifferentiation of myofibroblasts. Normal primary human adult lung fibroblasts were cultured for 24 hours with or without TGF-β1 and treated for 48 hours with PGE2. Gene expression levels were assessed from total RNA on the Affymetrix U219 microarray. TGF-β1 up-regulated 588 genes and down-regulated 689 genes compared with control cells. PGE2 reversed the expression of 363 (62%) of the TGF-β1-up-regulated genes and 345 (50%) of the TGF-β1-down-regulated genes. Genes up-regulated by TGF-β1 and reversed by PGE2 were enriched in annotations for Cell Adhesion, Contractile Fiber, and Actin Binding, whereas genes down-regulated by TGF-β1 but subsequently reversed by PGE2 were enriched in annotations for Glycoprotein, Polysaccharide Binding, and Regulation of Cell Migration. Surprisingly, the genes whose expression was affected by PGE2 differed between TGF-β1-induced myofibroblasts and undifferentiated fibroblasts. These data demonstrate the capacity of PGE2 to effect marked global alterations in the transcriptomic program of differentiated myofibroblasts and emphasize the considerable plasticity of these cells. PMID:26098591

  7. Effect of radiation on prostaglandin production by human bowel in vitro

    SciTech Connect

    Gal, D.; Strickland, D.M.; Lifshitz, S.; Buchsbaum, H.J.; Mitchell, M.D.

    1984-05-01

    The effect of gamma irradiation on the production of prostaglandins by human colon was investigated. Squares of tissue in organ culture dishes were irradiated with 500, 1000, or 2500 rad in single applications. Tissues that were not irradiated served as controls. After treatment the tissues were superfused and prostaglandin concentrations in the effluent fluid were determined. The rates of production of prostaglandins E/sub 2/ and F/sub 2..cap alpha../ by irradiated tissues were significantly lower than those of nonirradiated tissues. Neither the release of lactate dehydrogenase nor the rate of production of 13,14-dihydro-15-keto-prostaglandin F/sub 2..cap alpha../ were increased in the irradiated samples, suggesting that neither decreased cell viability nor increased prostaglandin metabolism accounted for the decreased prostaglandin production rates. The authors conclude that irradiation of the human colon in vitro results in an acute inhibition of prostaglandin synthesis. The cytoprotective nature of prostaglandins is discussed with regard to the possible pathophysiological significance of these findings.

  8. An Update of Microsomal Prostaglandin E Synthase-1 and PGE2 Receptors in Cardiovascular Health and Diseases

    PubMed Central

    2016-01-01

    Nonsteroidal anti-inflammatory drugs (NSAIDs), especially cyclooxygenase-2 (COX-2) selective inhibitors, are among the most widely used drugs to treat pain and inflammation. However, clinical trials have revealed that these inhibitors predisposed patients to a significantly increased cardiovascular risk, consisting of thrombosis, hypertension, myocardial infarction, heart failure, and sudden cardiac death. Thus, microsomal prostaglandin E (PGE) synthase-1 (mPGES-1), the key terminal enzyme involved in the synthesis of inflammatory prostaglandin E2 (PGE2), and the four PGE2 receptors (EP1–4) have gained much attention as alternative targets for the development of novel analgesics. The cardiovascular consequences of targeting mPGES-1 and the PGE2 receptors are substantially studied. Inhibition of mPGES-1 has displayed a relatively innocuous or preferable cardiovascular profile. The modulation of the four EP receptors in cardiovascular system is diversely reported as well. In this review, we highlight the most recent advances from our and other studies on the regulation of PGE2, particularly mPGES-1 and the four PGE2 receptors, in cardiovascular function, with a particular emphasis on blood pressure regulation, atherosclerosis, thrombosis, and myocardial infarction. This might lead to new avenues to improve cardiovascular disease management strategies and to seek optimized anti-inflammatory therapeutic options. PMID:27594972

  9. Human platelet/erythroleukemia cell prostaglandin G/H synthase: cDNA cloning, expression, and gene chromosomal assignment.

    PubMed

    Funk, C D; Funk, L B; Kennedy, M E; Pong, A S; Fitzgerald, G A

    1991-06-01

    Platelets metabolize arachidonic acid to thromboxane A2, a potent platelet aggregator and vasoconstrictor compound. The first step of this transformation is catalyzed by prostaglandin (PG) G/H synthase, a target site for nonsteroidal antiinflammatory drugs. We have isolated the cDNA for both human platelet and human erythroleukemia cell PGG/H synthase using the polymerase chain reaction and conventional screening procedures. The cDNA encoding the full-length protein was expressed in COS-M6 cells. Microsomal fractions from transfected cells produced prostaglandin endoperoxide-derived products which were inhibited by indomethacin and aspirin. Mutagenesis of the serine residue at position 529, the putative aspirin acetylation site, to an asparagine reduced cyclooxygenase activity to barely detectable levels, an effect observed previously with the expressed sheep vesicular gland enzyme. Platelet-derived growth factor and phorbol ester differentially regulated the expression of PGG/H synthase mRNA levels in the megakaryocytic/platelet-like HEL cell line. The PGG/H synthase gene was assigned to chromosome 9 by analysis of a human--hamster somatic hybrid DNA panel. The availability of platelet PGG/H synthase cDNA should enhance our understanding of the important structure/function domains of this protein and its gene regulation. PMID:1907252

  10. Human platelet/erythroleukemia cell prostaglandin G/H synthase: cDNA cloning, expression, and gene chromosomal assignment

    SciTech Connect

    Funk, C.D.; Funk, L.B.; Kennedy, M.E.; Pong, A.S.; Fitzgerald, G.A. )

    1991-06-01

    Platelets metabolize arachidonic acid to thromboxane A{sub 2}, a potent platelet aggregator and vasoconstrictor compound. The first step of this transformation is catalyzed by prostaglandin (PG) G/H synthase, a target site for nonsteroidal antiinflammatory drugs. We have isolated the cDNA for both human platelet and human erythroleukemia cell PGG/H synthase using the polymerase chain reaction and conventional screening procedures. The cDNA encoding the full-length protein was expressed in COS-M6 cells. Microsomal fractions from transfected cells produced prostaglandin endoperoxide derived products which were inhibited by indomethacin and aspirin. Mutagenesis of the serine residue at position 529, the putative aspirin acetylation site, to an asparagine reduced cyclooxygenase activity to barely detectable levels, an effect observed previously with the expressed sheep vesicular gland enzyme. Platelet-derived growth factor and phorbol ester differentially regulated the expression of PGG/H synthase mRNA levels in the megakaryocytic/platelet-like HEL cell line. The PGG/H synthase gene was assigned to chromosome 9 by analysis of a human-hamster somatic hybrid DNA panel. The availability of platelet PGG/H synthase cDNA should enhance our understanding of the important structure/function domains of this protein and it gene regulation.

  11. An Update of Microsomal Prostaglandin E Synthase-1 and PGE2 Receptors in Cardiovascular Health and Diseases.

    PubMed

    Yang, Guangrui; Chen, Lihong

    2016-01-01

    Nonsteroidal anti-inflammatory drugs (NSAIDs), especially cyclooxygenase-2 (COX-2) selective inhibitors, are among the most widely used drugs to treat pain and inflammation. However, clinical trials have revealed that these inhibitors predisposed patients to a significantly increased cardiovascular risk, consisting of thrombosis, hypertension, myocardial infarction, heart failure, and sudden cardiac death. Thus, microsomal prostaglandin E (PGE) synthase-1 (mPGES-1), the key terminal enzyme involved in the synthesis of inflammatory prostaglandin E2 (PGE2), and the four PGE2 receptors (EP1-4) have gained much attention as alternative targets for the development of novel analgesics. The cardiovascular consequences of targeting mPGES-1 and the PGE2 receptors are substantially studied. Inhibition of mPGES-1 has displayed a relatively innocuous or preferable cardiovascular profile. The modulation of the four EP receptors in cardiovascular system is diversely reported as well. In this review, we highlight the most recent advances from our and other studies on the regulation of PGE2, particularly mPGES-1 and the four PGE2 receptors, in cardiovascular function, with a particular emphasis on blood pressure regulation, atherosclerosis, thrombosis, and myocardial infarction. This might lead to new avenues to improve cardiovascular disease management strategies and to seek optimized anti-inflammatory therapeutic options. PMID:27594972

  12. Olfactory receptor for prostaglandin F2α mediates male fish courtship behavior.

    PubMed

    Yabuki, Yoichi; Koide, Tetsuya; Miyasaka, Nobuhiko; Wakisaka, Noriko; Masuda, Miwa; Ohkura, Masamichi; Nakai, Junichi; Tsuge, Kyoshiro; Tsuchiya, Soken; Sugimoto, Yukihiko; Yoshihara, Yoshihiro

    2016-07-01

    Pheromones play vital roles for survival and reproduction in various organisms. In many fishes, prostaglandin F2α acts not only as a female reproductive hormone, facilitating ovulation and spawning, but also as a sex pheromone inducing male reproductive behaviors. Here, we unravel the molecular and neural circuit mechanisms underlying the pheromonal action of prostaglandin F2α in zebrafish. Prostaglandin F2α specifically activates two olfactory receptors with different sensitivities and expression in distinct populations of ciliated olfactory sensory neurons. Pheromone information is then transmitted to two ventromedial glomeruli in the olfactory bulb and further to four regions in higher olfactory centers. Mutant male zebrafish deficient in the high-affinity receptor exhibit loss of attractive response to prostaglandin F2α and impairment of courtship behaviors toward female fish. These findings demonstrate the functional significance and activation of selective neural circuitry for the sex pheromone prostaglandin F2α and its cognate olfactory receptor in fish reproductive behavior. PMID:27239939

  13. Prostaglandins are not involved in the differentiation or growth of cultured small intestinal cells.

    PubMed

    Stange, E F; Schneider, A; Preclik, G; Ditschuneit, H

    1986-01-01

    Prostaglandins have been reported to exert trophic effects on gastrointestinal tissues. To determine whether there is a direct interaction with enterocytes, prostaglandins PGE2, PGF2 alpha, PGA2, PGB2 and the stable PGE2 derivative suleprost as well as the prostacyclin derivative nileprost were tested in rabbit ileal mucosa under organ culture conditions. At concentrations between 10(-9) and 10(-5) M, none of the prostaglandins significantly affected biopsy DNA or protein content, or the activity of the brush border enzymes alkaline phosphatase, lactase, sucrase or maltase. The inhibition of endogenous prostaglandin synthesis with indomethacin also failed to alter these parameters. Moreover, the growth rate of a rat duodenal crypt cell line was unaffected when cultured in the presence of PGE2, PGF2 alpha or indomethacin. Thus, there was no evidence for a direct effect of exogenous or endogenous prostaglandins or their deficiency on the differentiation or growth in cultured small intestinal cells. PMID:3817331

  14. CSF levels of prostaglandins, especially the level of prostaglandin D2, are correlated with increasing propensity towards sleep in rats.

    PubMed

    Ram, A; Pandey, H P; Matsumura, H; Kasahara-Orita, K; Nakajima, T; Takahata, R; Satoh, S; Terao, A; Hayaishi, O

    1997-03-14

    The concentration of PGD2, PGE2, and of PGF2 alpha was measured in the cerebrospinal fluid (CSF) collected from the cisterna magna of conscious rats (n = 29), which, chronically implanted with a catheter for the CSF sampling, underwent deprivation of daytime sleep. Significant elevation of the CSF level of PGD2 was observed following 2.5-h sleep deprivation (SD), and the elevation became more marked following 5- and 10-h SD, apparently reaching the maximum at 5-h SD (703 +/- 140 pg/ml (mean +/- S.E.M.) for baseline vs. 1734 +/- 363 pg/ml for SD, n = 10). The levels of PGE2, and PGF2 alpha also significantly increased following 5- and 10-h SD, but not following 2.5-h SD. It is unlikely that these changes were simply caused by some responses of the animals to stress stimuli, because stress stimuli derived from restraint of the animal at the supine position to a board for 1 h did not produce any acute responses in the CSF levels of prostaglandins (n = 13). In a different group of animals (n = 11) implanted with electrodes for recording electroencephalogram (EEG) and electromyogram (EMG) in addition to the catheter, the levels of the prostaglandins in CSF were determined for slow-wave sleep (SWS) and wakefulness in the day and for SWS and wakefulness in the night. The highest PGD2 value was obtained at daytime SWS, whereas the lowest was at night wakefulness; furthermore, a significant difference was observed between SWS and wakefulness rather than between day and night. The CSF level of PGE2 also showed a similar tendency. In an additional group of animals (n = 6), not only PGD2 but also PGE2 and PGF2 alpha significantly increased the sleeping time of the animal when applied into the subarachnoid space underlying the ventral surface area of the rostral basal forebrain, the previously defined site of action for the sleep-promoting effect of PGD2. The promotion of sleep by PGE2 applied to the subarachnoid space was an effect completely opposite to the well

  15. In Vivo Mechanical Loading Rapidly Activates β–catenin Signaling in Osteocytes through a Prostaglandin Mediated Mechanism

    PubMed Central

    Lara-Castillo, N; Kim-Weroha, NA; Kamel, MA; Javaheri, B; Ellies, DL; Krumlauf, RE; Thiagarajan, G; Johnson, ML

    2015-01-01

    The response of the skeleton to loading appears to be mediated through the activation of the Wnt/β-catenin signaling pathway and osteocytes have long been postulated to be the primary mechanosensory cells in bone. To examine the kinetics of the mechanoresponse of bone and cell types involved in the in vivo, we performed forearm loading of 17-week-old female TOPGAL mice. β-catenin signaling was observed only in embedded osteocytes, not osteoblasts, at 1 hour post loading, spreading to additional osteocytes and finally to cells on the bone surface by 24 hrs. This early activation at 1 hour appeared to be independent of receptor (Lrp5/6) mediated activation as it occurred in the presence of the inhibitors sclerostin and/or Dkk1. The COX-2 inhibitor, Carprofen, blocked the activation of β-catenin signaling and decline in sclerostin positive osteocytes post-loading implying an important role for prostaglandin. In vitro, PI3K/Akt activation was shown to be required for β-catenin nuclear translocation downstream from prostaglandin in MLO-Y4 osteocyte-like cells supporting this mechanism. Downstream targets of β-catenin signaling, sclerostin and Dkk1, were also examined and found to be significantly down regulated in osteocytes in vivo at 24 hours post-loading. The pattern of initially activated osteocytes appeared random and in order to understand this heterogeneous expression, a novel finite element model of the strain field in the ulna was developed, which predicts highly variable local magnitudes of strain experienced by osteocytes. In summary, both in vivo and in vitro models show the rapid activation of β-catenin in response to load through the early release of prostaglandin and that strain fields in the bone are extremely heterogeneous resulting in heterogeneous activation of the β-catenin pathway in osteocytes in vivo. PMID:25836764

  16. Induction of hyaluronic acid synthase 2 (HAS2) in human vascular smooth muscle cells by vasodilatory prostaglandins.

    PubMed

    Sussmann, M; Sarbia, M; Meyer-Kirchrath, J; Nüsing, R M; Schrör, K; Fischer, J W

    2004-03-19

    Hyaluronic acid (HA) is a prominent constituent of the extracellular matrix of atherosclerotic vascular lesions in humans known to modulate vascular smooth muscle phenotype. The regulation of HA synthesis by vasodilatory prostaglandins was analyzed in human arterial smooth muscle cells (SMCs). The prostacyclin analogue, iloprost (100 nmol/L), markedly increased pericellular formation of HA coats and HA secretion into the cell culture medium in human arterial SMCs (8.7+/-1.6-fold). Expression of HA synthase 2 (HAS2) was determined by semiquantitative RT-PCR and found to be strongly upregulated at concentrations of iloprost between 1 and 100 nmol/L after 3 hours. Furthermore, endogenous cyclooxygenase-2 (COX2) activity was required for basal expression of HAS2 mRNA in SMCs in vitro. Total HA secretion in response to iloprost was markedly decreased by RNA interference (RNAi), specific for HAS2. In addition, siRNA targeting HAS2 strongly increased the spreading of human SMCs compared with mock-transfected cells. HAS2 mRNA levels were also stimulated by a selective prostacyclin receptor (IP) agonist, cicaprost (10 nmol/L), prostaglandin E(2) (10 nmol/L), and the EP(2) receptor agonist, butaprost (1 micromol/L). Induction of HAS2 mRNA and HA synthesis by prostaglandins was mimicked by stable cAMP analogues and forskolin. In human atherectomy specimens from the internal carotid artery, HA deposits and COX2 expression colocalized frequently. In addition, strong EP(2) receptor expression was detected in SMCs in HA-rich areas. Therefore, upregulation of HAS2 expression via EP(2) and IP receptors might contribute to the accumulation of HA during human atherosclerosis, thereby mediating proatherosclerotic functions of COX2. PMID:14752026

  17. Prostanoid signaling: dual role for prostaglandin E2 in neurotoxicity

    PubMed Central

    Milatovic, Dejan; Montine, Thomas J.; Aschner, Michael

    2011-01-01

    The prostanoids, a naturally occurring subclass of eicosanoids, are lipid mediators generated through oxidative pathways from arachidonic acid. These cyclooxygenase metabolites, consisting of the prostaglandins (PG), prostacyclin and tromboxane, are released in response to a variety of physiological and pathological stimuli in almost all organs, including the brain. They are produced by various cell types and act upon targeted cells via specific G protein-coupled receptors. The existence of multiple receptors, cross-reactivity and coupling to different signal transduction pathways for each prostanoid, collectively establish their diverse effects. Notably, these effects can occur in functionally opposing directions within the same cell or organ. Prostaglandin E2 (PGE2) is the most versatile prostanoid because of its receptors, E Prostanoid (EP) receptor subtypes 1 through 4, its biological heterogeneity and its differential expression on neuronal and glial cells throughout the central nervous system. Since PGE2 plays an important role in processes associated with various neurological diseases, this review focuses on its dual neuroprotective and neurotoxic role in EP receptor subtype signaling pathways in different models of brain injury. PMID:21376752

  18. Prostaglandin E receptor 4 (EP4) promotes colonic tumorigenesis.

    PubMed

    Chang, Jian; Vacher, Jean; Yao, Bing; Fan, Xiaofeng; Zhang, Bixiang; Harris, Raymond C; Zhang, Ming-Zhi

    2015-10-20

    Colorectal cancer (CRC) continues to be a major cause of morbidity and mortality. Although the factors underlying CRC development and progression are multifactorial, there is an important role for tumor-host interactions, especially interactions with myeloid cells. There is also increasing evidence that cyclooxygenase-derived prostaglandins are important mediators of CRC development and growth. Although prevention trials with either nonselective NSAIDs or COX-2 selective agents have shown promise, the gastrointestinal or cardiovascular side effects of these agents have limited their implementation. The predominant prostaglandin involved in CRC pathogenesis is PGE2. Since myeloid cells express high levels of the PGE2 receptor subtype, EP4, we selectively ablated EP4 in myeloid cells and studied adenoma formation in a mouse model of intestinal adenomatous polyposis, ApcMin/+ mice. ApcMin/+mice with selective myeloid cell deletion of EP4 had marked inhibition of both adenoma number and size, with associated decreases in mTOR and ERK activation. Either genetic or pharmacologic inhibition of EP4 receptors led to an anti-tumorigenic M1 phenotype of macrophages/dendritic cells. Therefore, PGE2-mediated EP4 signaling in myeloid cells promotes tumorigenesis, suggesting EP4 as a potentially attractive target for CRC chemoprevention or treatment. PMID:26378024

  19. Prostaglandin E receptor 4 (EP4) promotes colonic tumorigenesis

    PubMed Central

    Chang, Jian; Vacher, Jean; Yao, Bing; Fan, Xiaofeng; Zhang, Bixiang; Harris, Raymond C.; Zhang, Ming-Zhi

    2015-01-01

    Colorectal cancer (CRC) continues to be a major cause of morbidity and mortality. Although the factors underlying CRC development and progression are multifactorial, there is an important role for tumor-host interactions, especially interactions with myeloid cells. There is also increasing evidence that cyclooxygenase-derived prostaglandins are important mediators of CRC development and growth. Although prevention trials with either nonselective NSAIDs or COX-2 selective agents have shown promise, the gastrointestinal or cardiovascular side effects of these agents have limited their implementation. The predominant prostaglandin involved in CRC pathogenesis is PGE2. Since myeloid cells express high levels of the PGE2 receptor subtype, EP4, we selectively ablated EP4 in myeloid cells and studied adenoma formation in a mouse model of intestinal adenomatous polyposis, ApcMin/+ zmice. ApcMin/+mice with selective myeloid cell deletion of EP4 had marked inhibition of both adenoma number and size, with associated decreases in mTOR and ERK activation. Either genetic or pharmacologic inhibition of EP4 receptors led to an anti-tumorigenic M1 phenotype of macrophages/dendritic cells. Therefore, PGE2-mediated EP4 signaling in myeloid cells promotes tumorigenesis, suggesting EP4 as a potentially attractive target for CRC chemoprevention or treatment. PMID:26378024

  20. Inhibition of nitric oxide and prostaglandins, but not endothelial-derived hyperpolarizing factors, reduces blood flow and aerobic energy turnover in the exercising human leg.

    PubMed

    Mortensen, Stefan P; González-Alonso, José; Damsgaard, Rasmus; Saltin, Bengt; Hellsten, Ylva

    2007-06-01

    Prostaglandins, nitric oxide (NO) and endothelial-derived hyperpolarizing factors (EDHFs) are substances that have been proposed to be involved in the regulation of skeletal muscle blood flow during physical activity. We measured haemodynamics, plasma ATP at rest and during one-legged knee-extensor exercise (19 +/- 1 W) in nine healthy subjects with and without intra-arterial infusion of indomethacin (Indo; 621 +/- 17 microg min(-1)), Indo + N(G)-monomethyl-L-arginine (L-NMMA; 12.4 +/- 0.3 mg min(-1)) (double blockade) and Indo + L-NMMA + tetraethylammonium chloride (TEA; 12.4 +/- 0.3 mg min(-1)) (triple blockade). Double and triple blockade lowered leg blood flow (LBF) at rest (P<0.05), while it remained unchanged with Indo. During exercise, LBF and vascular conductance were 2.54 +/- 0.10 l min(-1) and 25 +/- 1 mmHg, respectively, in control and they were lower with double (33 +/- 3 and 36 +/- 4%, respectively) and triple (26 +/- 4 and 28 +/- 3%, respectively) blockade (P<0.05), while there was no difference with Indo. The lower LBF and vascular conductance with double and triple blockade occurred in parallel with a lower O(2) delivery, cardiac output, heart rate and plasma [noradrenaline] (P<0.05), while blood pressure remained unchanged and O(2) extraction and femoral venous plasma [ATP] increased. Despite the increased O(2) extraction, leg was 13 and 17% (triple and double blockade, respectively) lower than control in parallel to a lower femoral venous temperature and lactate release (P<0.05). These results suggest that NO and prostaglandins play important roles in skeletal muscle blood flow regulation during moderate intensity exercise and that EDHFs do not compensate for the impaired formation of NO and prostaglandins. Moreover, inhibition of NO and prostaglandin formation is associated with a lower aerobic energy turnover and increased concentration of vasoactive ATP in plasma. PMID:17347273

  1. A catalytically-inactive snake venom Lys49 phospholipase A₂ homolog induces expression of cyclooxygenase-2 and production of prostaglandins through selected signaling pathways in macrophages.

    PubMed

    Moreira, Vanessa; de Castro Souto, Pollyana Cristina Maggio; Ramirez Vinolo, Marco Aurélio; Lomonte, Bruno; María Gutiérrez, José; Curi, Rui; Teixeira, Catarina

    2013-05-15

    The effects of a snake venom Lys-49 phospholipase A2 (PLA2) homolog named MT-II, devoid of enzymatic activity, on the biosynthesis of prostaglandins and protein expression of cyclooxygenase-2 (COX-2) and signaling pathways involved were evaluated in mouse macrophages in culture and in peritoneal cells ex vivo. Stimulation of macrophages with MT-II leads to production of prostaglandin D2 (PGD2) and prostaglandin E2 (PGE2) and protein expression of COX-2 and microsomal prostaglandin E synthase-1 (mPGES-1). Inhibition of cytosolic PLA2 (cPLA2), but not Ca(2+) independent PLA2 (iPLA2) reduced release of PGD2 and PGE2 and expression of COX-2 induced by MT-II. Inhibition of nuclear factor κB (NF-κB) significantly reduced MT-II-induced PGE2, but not PGD2 production and COX-2 expression. Inhibitors of either protein kinase C (PKC), protein tyrosine kinase (PTK), or extracellular signal-regulated kinase (ERK) pathways abrogated MT-II-induced NF-κB activation and reduced COX-2 expression and PGE2 release, whereas the p38 mitogen-activated protein kinase (MAPK) inhibitor reduced MT-II-induced COX-2 expression and PGD2 production. Inhibition of phosphatidylinositol-3-kinase (PI3K) pathway abrogated MT-II-induced NF-κB activation, but affected neither prostaglandins production nor COX-2 expression. MT-II-induced production of PGD2 and PGE2 and COX-2 expression were also observed in vivo after intraperitoneal injection into mice. Collectively, our data demonstrate that a catalytically-inactive PLA2 homolog is capable of inducing prostaglandins biosynthesis and COX-2 expression in macrophages in both in vitro and in vivo models, indicating that the enzymatic activity of PLA2 is not necessary to trigger these effects. MT-II-activated NF-κB, cPLA2 and distinct protein kinases are the principal steps involved in these cellular events. PMID:23416211

  2. Prostaglandin I2 and prostaglandin E2 modulate human intrarenal artery contractility through prostaglandin E2-EP4, prostacyclin-IP, and thromboxane A2-TP receptors.

    PubMed

    Eskildsen, Morten P; Hansen, Pernille B L; Stubbe, Jane; Toft, Anja; Walter, Steen; Marcussen, Niels; Rasmussen, Lars M; Vanhoutte, Paul M; Jensen, Boye L

    2014-09-01

    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 receptors. Intrarenal arteries were microdissected from human nephrectomy samples (n=53, median diameter ≈362 μm, 88% viable, 76% relaxed in response to acetylcholine). Rings were suspended in myographs to record force development. In vessels with K(+)-induced tension (EC70: -log [mol/L]=1.36±0.03), PGE2 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 receptor antagonist (BR5064, 10(-8) mol/L). Pretreatment of quiescent arteries with PGE2 for 5 minutes (10(-6) mol/L) led to a significant right shift of the concentration-response to norepinephrine (EC50 from 6.6±0.1-5.9±0.1). In intrarenal arteries with K(+)-induced tone, PGE2 and PGI2 at 10(-5) mol/L elicited increased tension. This was abolished by thromboxane receptor (TP) antagonist (S18886, 10(-6) mol/L). A TP agonist (U46619, n=6) evoked tension (EC50=8.1±0.2) that was inhibited by S18886. Polymerase chain reaction and immunoblotting showed EP4, IP, and TP receptors in intrarenal arteries. 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. PMID:24914192

  3. Prostaglandin E2-increased thermosensitivity of anterior hypothalamic neurons is associated with depressed inhibition.

    PubMed

    Tabarean, Iustin V; Behrens, M Margarita; Bartfai, Tamas; Korn, Henri

    2004-02-24

    Temperature responses of anterior hypothalamic neurons are considered key elements in the regulation of the temperature setpoint of homeotherms. We have investigated the sensitivity to warming of cultured neurons of the AH from mice with electrophysiological and immunocytochemical techniques. In control experiments, only approximately 9% of the 3- to 5-week-old cells exhibited changes of their basic firing rate when the temperature was raised from 37 degrees C to 40 degrees C. This ratio was increased to 27% after the cultures were "primed" by adding prostaglandin E2 (PGE2), an endogenous pyrogen, in the extracellular medium. In these neurons the firing rate was significantly increased, and the frequency of the gamma gamma-aminobutyric acid (GABA) inhibitory postsynaptic potentials was markedly decreased. In contrast, the resting potential and membrane resistance of the recorded cells remained unchanged. PGE2 was found to decrease the level of phosphorylation of the extracellular signal-regulated kinases 1 and 2 in a subset of GABAergic neurons that express the E-prostanoid receptor type 3. Inhibition of ERK1/2 by U0126 mimicked the effects of PGE2. These data indicate that PGE2 acts primarily on the excitability of GABAergic presynaptic cells, most likely via alterations of voltage-gated K+ channels. Our results also suggest that far from being an inherent property of a specialized class of neurons, the degree of thermosensitivity can be strongly modulated by synaptic activity and is a more adaptive property of hypothalamic neurons than previously thought. PMID:14983053

  4. Characterization of the promoter of human CRTh2, a prostaglandin D{sub 2} receptor

    SciTech Connect

    Quapp, Russell; Madsen, Norman; Cameron, Lisa

    2007-11-30

    Chemoattractant-receptor homologous molecule expressed on Th2 cells (CRTh2) is a receptor for prostaglandin (PG)D{sub 2}, a lipid mediator involved in allergic inflammation. CRTh2 is expressed by Th2 cells, eosinophils and basophils and PDG{sub 2}-CRTh2 signaling induces calcium mobilization, cell migration and expression of the Th2 cytokines IL-4, IL-5, and IL-13. Despite the role of CRTh2 in allergic inflammation, transcriptional regulation of this gene has not been studied. Here, we demonstrated that a reporter construct of the CRTh2 promoter was induced following T cell stimulation. This activity could be further enhanced by over-expression of GATA-3, but not NFAT2 or STAT6. Electromobility shift assay demonstrated GATA-3 binding to a probe from the CRTh2 promoter. This study provides the first detailed analysis of transcriptional regulation of the human CRTh2 promoter. These findings may help identify strategies to attenuate expression of this gene and influence the maintenance and proliferation of Th2 cells in allergic inflammation.

  5. Brain Levels of Prostaglandins, Endocannabinoids, and Related Lipids Are Affected by Mating Strategies

    PubMed Central

    Stuart, Jordyn M.; Paris, Jason J.; Frye, Cheryl; Bradshaw, Heather B.

    2013-01-01

    Background. Endogenous cannabinoids (eCBs) are involved in the development and regulation of reproductive behaviors. Likewise, prostaglandins (PGs) drive sexual differentiation and initiation of ovulation. Here, we use lipidomics strategies to test the hypotheses that mating immediately activates the biosynthesis and/or metabolism of eCBs and PGs and that specific mating strategies differentially regulate these lipids in the brain. Methods. Lipid extractions and tandem mass spectrometric analysis were performed on brains from proestrous rats that had experienced one of two mating strategies (paced or standard mating) and two nonmated groups (chamber exposed and home cage controls). Levels of PGs (PGE2 and PGF2alpha), eCBs (AEA and 2-AG, N-arachidonoyl glycine), and 4 related lipids (4 N-acylethanolamides) were measured in olfactory bulb, hypothalamus, hippocampus, thalamus, striatum, midbrain, cerebellum, and brainstem. Results. Overall, levels of these lipids were significantly lower among paced compared to standard mated rats with the most dramatic decreases observed in brainstem, hippocampus, midbrain, and striatum. However, chamber exposed rats had significantly higher levels of these lipids compared to home cage controls and paced mated wherein the hippocampus showed the largest increases. Conclusions. These data demonstrate that mating strategies and exposure to mating arenas influence lipid signaling in the brain. PMID:24369463

  6. EP3, Prostaglandin E2 Receptor Subtype 3, Associated with Neuronal Apoptosis Following Intracerebral Hemorrhage.

    PubMed

    Ni, Haidan; Shen, Jiabing; Song, Yan; Cao, Maohong; Liu, Xiaorong; Huang, Jie; Zhang, Weidong; Xie, Lili; Ning, Xiaojin; Ke, Kaifu

    2016-08-01

    EP3 is prostaglandin E2 receptor subtype 3 and mediates the activation of several signaling pathways, changing in cAMP levels, calcium mobilization, and activation of phospholipase C. Previous studies demonstrated a direct role for EP3 in various neurodegenerative disorders, such as stroke and Alzheimer disease. However, the distribution and function of EP3 in ICH diseases remain unknown. Here, we demonstrate that EP3 may be involved in neuronal apoptosis in the processes of intracerebral hemorrhage (ICH). From the results of Western blot and immunohistochemistry, we obtained a significant up-regulation of EP3 in neurons adjacent to the hematoma following ICH. Up-regulation of EP3 was found to be accompanied by the increased expression of active caspase-3 and pro-apoptotic Bcl-2-associated X protein (Bax) and decreased expression of anti-apoptotic protein B cell lymphoma-2 (Bcl-2) in vivo and vitro studies. Furthermore, the expression of these three proteins reduced active caspase-3 and Bax expression, while increased Bcl-2 were changed after knocking down EP3 by RNA interference in PC12 cells, further confirmed that EP3 might exert its pro-apoptotic function on neuronal apoptosis. Thus, EP3 may play a role in promoting the neuronal apoptosis following ICH. PMID:26718710

  7. Effects of methylxanthines on urinary prostaglandin E excretion in rats.

    PubMed

    Takeuchi, K; Kogo, H; Aizawa, Y

    1981-04-01

    Effect of methylxanthines (theophylline, theobromine and caffeine) on urinary prostaglandin E (PGE) excretion in male rats was studied. Oral administration of xanthines significantly increased the urinary excretion of PGE. Dose-response studies showed that the maximal excretion of urinary PGE and water was obtained by administration of theophylline (50 mg/kg), where the increase in PGE was about 20 times that of the control. The excretion of urinary sodium, potassium and chloride was also markedly increased by xanthines, particularly, theophylline. Increases in urinary PGE excretion, urine volume and electrolytes excretion were inhibited by 10 mg/kg of indomethacin administered prior to theophylline. The increase of urinary PGE excretion after theophylline administration (50 mg/kg) preceded increases in water and sodium excretion. These results suggest that renal PGE mediates, at least in part, the diuretic effect of theophylline. PMID:7311144

  8. Metabolism of prostaglandin E1 in dog kidneys

    PubMed Central

    Nakano, J.

    1970-01-01

    1. The biotransformation of prostaglandin E1 (PGE1) was studied in the isolated, perfused dog kidneys. 2. An average 43% of PGE1 was converted into the less polar metabolite I by a single passage through the kidney. As the re-circulation of the perfusate continued, PGE1 was converted not only into metabolite I but also the least polar metabolite II. The velocity of the conversion of PGE1 into metabolite I was significantly greater than that into metabolite II. Usually, six passages elapsed before maximum degradation of PGE1 occurred. 3. Further separation with silicic acid column chromatography and gas-liquid chromatography showed that metabolite II consists of two individual metabolites, metabolite IIa and metabolite IIb. 4. The present study indicates that the kidney biotransforms PGE1 rather rapidly into three metabolites which are less polar than PGE1. PMID:5492900

  9. Prostaglandin inhibitor and radiotherapy in advanced head and neck cancers

    SciTech Connect

    Pillsbury, H.C. III; Webster, W.P.; Rosenman, J.

    1986-05-01

    Radiotherapy is the usual mode of treatment for unresectable head and neck cancer. To improve cure rates, extend survival, and reduce morbidity, we use accelerated hyperfractionation radiotherapy and an adjuvant drug to inhibit prostaglandin synthesis. In this study, 19 patients received 300 rad/day of radiotherapy in two equally divided doses to a total dose averaging 6,200 rad. Either indomethacin, 25 mg, or placebo was given four times a day in a double-blind fashion during therapy. Radiation mucositis was graded as 0 to 4+; pain, nutritional status, and tumor status were monitored daily and recorded biweekly. Evaluation of the data showed delayed mucositis in the experimental group for grades 1 to 3, with a significant difference at grade 3 compared with controls. The significance of a long-term comparison of cure rates would be doubtful considering the heterogeneity of the primary sites and regional disease in this group coupled with the small size of our study.

  10. Prostaglandin ethanolamides attenuate damage in a human explant colitis model.

    PubMed

    Nicotra, Lauren L; Vu, Megan; Harvey, Benjamin S; Smid, Scott D

    2013-01-01

    Endocannabinoids are protective in animal colitis models. As endocannabinoids also form novel prostaglandin ethanolamides (prostamides) via COX-2, we investigated the effects of prostamides and other COX-2 mediators on tissue damage in an ex vivo human mucosal explant colitis model. Healthy human colonic mucosae were incubated with pro-inflammatory cytokines TNF-α and IL-1β to elicit colitis-like tissue damage. The PGF-ethanolamide analogue, bimatoprost decreased colitis scores which were reversed by a prostamide-specific antagonist AGN 211334, but not the FP receptor antagonist AL-8810. PGF-ethanolamide and PGE-ethanolamide also reduced cytokine-evoked epithelial damage. Anandamide was protective in the explant colitis model; however COX-2 inhibition did not alter its effects, associated with a lack of COX-2 induction in explant mucosal tissue. These findings support an anti-inflammatory role for prostamides and endocannabinoids in the human colon. PMID:23380599

  11. Hydrogen peroxide induces spawning in mollusks, with activation of prostaglandin endoperoxide synthetase.

    PubMed

    Morse, D E; Duncan, H; Hooker, N; Morse, A

    1977-04-15

    Addition of hydrogen peroxide to seawater causes synchronous spawning in gravid male and female abalones, and certain other mollusks as well. This effect is blocked by exposure of the animals to aspirin, an inhibitor of the enzyme catalyzing oxidative synthesis of prostaglandin endoperoxide. Hydrogen peroxide activates this enzymatic reaction in cell-free extracts prepared from abalone eggs (a very rich source of the prostaglandin endoperoxide synthetase); this effect appears to reveal a fundamental property of prostaglandin endoperoxide synthesis. Applicability of these findings to both mariculture and medical purposes is suggested. PMID:403609

  12. Expression of gastric antisecretory and prostaglandin E receptor binding activity of misoprostol by misoprostol free acid.

    PubMed

    Tsai, B S; Kessler, L K; Stolzenbach, J; Schoenhard, G; Bauer, R F

    1991-05-01

    In enriched canine parietal cell preparations, misoprostol, an analog of prostaglandin E1 methyl ester, was rapidly deesterified to misoprostol free acid. Under this circumstance, misoprostol and misoprostol free acid exhibited equal antisecretory potency against histamine-stimulated acid secretion and bound equally well to prostaglandin E receptors. When the deesterification of misoprostol was inhibited by paraoxon, an esterase inhibitor, the antisecretory and receptor binding activity of misoprostol was markedly reduced, with potency much less than misoprostol free acid. These results indicate that misoprostol free acid is the active biological form of misoprostol that binds to prostaglandin E receptors and mediates the antisecretory action of misoprostol. PMID:1850690

  13. Acute Hemoperitoneum after Administration of Prostaglandin E2 for Induction of Labour

    PubMed Central

    Zhang, Zhenyu; Lou, Jiangyan

    2015-01-01

    Prostaglandin E2 is widely used in obstetrics and is thought to be relatively safe for cervical ripening and induction of labour. Here we present a case in which acute hemoperitoneum was observed after administration of prostaglandin E2 in a pregnant woman. The patient had a history of endometriosis, and a severe pelvic adhesion (ASRM stage IV) was found during her last laparoscopic surgery 3 years previously. In cases with endometriosis, use of prostaglandin E2 for induction of labour in pregnant women must be done cautiously. PMID:26495145

  14. Treatment of renal colic by prostaglandin synthetase inhibitors and avafortan (analgesic antispasmodic).

    PubMed

    el-Sherif, A E; Foda, R; Norlen, L J; Yahia, H

    1990-12-01

    In a study of the pain-relieving effect of 3 drugs commonly used to treat acute renal colic in this hospital, intravenous indomethacin and intramuscular diclofenac (prostaglandin synthetase inhibitors) were compared with intravenous Avafortan (analgesic antispasmodic). As first-line analgesics, prostaglandin synthetase inhibitors, if given intravenously, offer an effective alternative to Avafortan. Of 145 patients studied, 32 required a second injection for complete relief of pain. Administering a second dose of prostaglandin synthetase inhibitors resulted in equally significant pain relief rate even though the route was intramuscular. PMID:2265331

  15. Fetal placental prostaglandin metabolism in the peripartum cow

    SciTech Connect

    Gross, T.S.; Williams, W.F.; Lewis, G.S.

    1986-03-05

    Previous results demonstrate that fetal placental tissue synthesizes prostaglandin E (PGE) prior to parturition. When placental membranes do not separate postpartum, PGE synthesis is maintained, while prostaglandin F (PGF) synthesis predominates when the membranes separate. Concurrent with separation is a decline in fetal placental binucleate cell (BNC) numbers. These data suggest a fetal placental conversion of PGE to PGF. For this experiment, placentomes were collected at ten days prepartum (PRE, n=12) and within 1 hr postpartum. Nine of the postpartum animals had fetal membrane separation within 12 hr postpartum (S) and eight did not exhibit membrane separation (NS). For each placentome, fetal (villi) components were manually isolated and examined for the ability to interconvert /sup 3/H labeled PGE/sub 2/ and PGF/sub 2/. All villi were unable to convert PGE/sub 2/ to PGF/sub 2/ (P > .05). The PRE and NS villi were able to convert PGF/sub 2/ to PGE/sub 2/ (P < .05) while S villi could not. When the BNC decline in numbers, as in the S villi, the ability to convert PGF/sub 2/ to PGE/sub 2/ (P < .05) while S villi could not. When the BNC decline in numbers, as in the S villi, the ability to convert PGF/sub 2/ to PGE/sub 2/ also declines (P < .05). These data suggest that peripartum fetal placental tissue might synthesize PGF which is then converted to PGE. It is possible that the BNC are directly converting PGF to PGE or that they are modulating this conversion. Therefore, with a decline in BNC numbers, PGF synthesis would predominate.

  16. Assignment of the human prostaglandin-endoperoxide synthase 2 (PTGS2) gene to 1q25 by fluorescence in situ hybridization

    SciTech Connect

    Tay, A.; Squire, J.A.; Goldberg, H.; Skorecki, K.

    1994-10-01

    A major mechanism for the regulation of prostaglandin synthesis occurs at the level of cyclooxygenase, also known as prostaglandin-endoperoxide synthase (PTGS). Two isoforms of PTGS have been identified: PTGS1, encoded by a 2.8-kb mRNA and a mitogen-inducible form, PTGS2, encoded by a 4.5-kb mRNA. We report here the assignment of the human PTGS2 gene to chromosome 1q25 by fluorescence in situ hybridization (FISH). We note with interest the physical proximity of the PTGS2 gene to that of cytosolic phospholipase A2 (cPLA2), which we have previously mapped to chromosome 1q24-q25. In contrast, the PTGS1 gene has been mapped to chromosome 9. Since cPLA2 and PTGS2 are key enzymes in the synthesis of prostaglandins and thromboxane, the possible implication of this proximity could mean that polymorphic markers already determined for the cPLA2 gene may also prove to be useful as markers for the PTGS2 gene as well. 10 refs., 1 fig.

  17. Induction of human microsomal prostaglandin E synthase 1 by activated oncogene RhoA GTPase in A549 human epithelial cancer cells

    SciTech Connect

    Choi, Hye Jin; Lee, Dong-Hyung; Park, Seong-Hwan; Kim, Juil; Do, Kee Hun; An, Tae Jin; Ahn, Young Sup; Park, Chung Berm; Moon, Yuseok

    2011-09-30

    Highlights: {yields} As a target of oncogene RhoA-linked signal, a prostaglandin metabolism is assessed. {yields} RhoA activation increases PGE{sub 2} levels and its metabolic enzyme mPGES-1. {yields} RhoA-activated NF-{kappa}B and EGR-1 are positively involved in mPGES-1 induction. -- Abstract: Oncogenic RhoA GTPase has been investigated as a mediator of pro-inflammatory responses and aggressive carcinogenesis. Among the various targets of RhoA-linked signals, pro-inflammatory prostaglandin E{sub 2} (PGE{sub 2}), a major prostaglandin metabolite, was assessed in epithelial cancer cells. RhoA activation increased PGE{sub 2} levels and gene expression of the rate-limiting PGE{sub 2} producing enzymes, cyclooxygenase-2 and microsomal prostaglandin E synthase 1 (mPGES-1). In particular, human mPGES-1 was induced by RhoA via transcriptional activation in control and interleukin (IL)-1{beta}-activated cancer cells. To address the involvement of potent signaling pathways in RhoA-activated mPGES-1 induction, various signaling inhibitors were screened for their effects on mPGES-1 promoter activity. RhoA activation enhanced basal and IL-1{beta}-mediated phosphorylated nuclear factor-{kappa}B and extracellular signal-regulated kinase1/2 proteins, all of which were positively involved in RhoA-induced gene expression of mPGES-1. As one potent down-stream transcription factor of ERK1/2 signals, early growth response gene 1 product also mediated RhoA-induced gene expression of mPGES-1 by enhancing transcriptional activity. Since oncogene-triggered PGE{sub 2} production is a critical modulator of epithelial tumor cells, RhoA-associated mPGES-1 represents a promising chemo-preventive or therapeutic target for epithelial inflammation and its associated cancers.

  18. Enteric glia modulate epithelial cell proliferation and differentiation through 15-deoxy-Δ12,14-prostaglandin J2

    PubMed Central

    Bach-Ngohou, Kalyane; Mahé, Maxime M; Aubert, Philippe; Abdo, Hind; Boni, Sébastien; Bourreille, Arnaud; Denis, Marc G; Lardeux, Bernard; Neunlist, Michel; Masson, Damien

    2010-01-01

    The enteric nervous system (ENS) and its major component, enteric glial cells (EGCs), have recently been identified as a major regulator of intestinal epithelial barrier functions. Indeed, EGCs inhibit intestinal epithelial cell (IEC) proliferation and increase barrier resistance and IEC adhesion via the release of EGC-derived soluble factors. Interestingly, EGC regulation of intestinal epithelial barrier functions is reminiscent of previously reported peroxisome proliferator-activated receptor γ (PPARγ)-dependent functional effects. In this context, the present study aimed at identifying whether EGC could synthesize and release the main PPARγ ligand, 15-deoxy-Δ12,14-prostaglandin J2 (15dPGJ2), and regulate IEC functions such as proliferation and differentiation via a PPARγ dependent pathway. First, we demonstrated that the lipocalin but not the haematopoetic form for prostaglandin D synthase (PGDS), the enzyme responsible of 15dPGJ2 synthesis, was expressed in EGCs of the human submucosal plexus and of the subepithelium, as well as in rat primary culture of ENS and EGC lines. Next, 15dPGJ2 was identified in EGC supernatants of various EGC lines. 15dPGJ2 reproduced EGC inhibitory effects upon IEC proliferation, and inhibition of lipocalin PGDS expression by shRNA abrogated these effects. Furthermore, EGCs induced nuclear translocation of PPARγ in IEC, and both EGC and 15dPGJ2 effects upon IEC proliferation were prevented by the PPARγ antagonist GW9662. Finally, EGC induced differentiation-related gene expression in IEC through a PPARγ-dependent pathway. Our results identified 15dPGJ2 as a novel glial-derived mediator involved in the control of IEC proliferation/differentiation through activation of PPARγ. They also suggest that alterations of glial PGDS expression may modify intestinal epithelial barrier functions and be involved in the development of pathologies such as cancer or inflammatory bowel diseases. PMID:20478974

  19. The release of prostaglandin E2 from the skin of the plaice, Pleuronectes platessa L.

    PubMed Central

    Anderson, A. A.; Fletcher, T. C.; Smith, G. M.

    1979-01-01

    1 A fungal extract which produces a cutaneous hypersensitivity reaction in the plaice, Pleuronectes platessa L., was incubated in vitro with the skin of this teleost fish. Samples of incubation media were assayed for smooth muscle stimulating activity. 2 Prostaglandin E2 was identified by bioassay, thin-layer chromatography, ultraviolet absorption spectroscopy and gas chromatography--mass spectrometry. Release from challenged skin was maximum after 60 min incubation. 3 Analysis of the fatty acid composition of plaice skin showed that although arachidonic acid was present (3% of total fatty acids), the precursor of prostaglandin E3, eicosapentaenoic acid contributed 9% of total. 4 Indomethacin (50 mg/kg i.p) did not inhibit the erythema induced by the fungal extract, whilst a dose of 1 mg/kg maximally inhibited prostaglandin release from skin on incubation in vitro. 5 It is concluded that prostaglandins do not have an exclusive role in the mediation of the hypersensitivity reaction. PMID:465893

  20. Management of severe preeclampsia detected in early labor by prostaglandin A1 or dihydralazine infusions.

    PubMed

    Toppozada, M K; Darwish, E; Barakat, A A

    1991-05-01

    The presence of severe pregnancy-induced hypertension at the onset of labor requires therapy with a potent hypotensive agent. Prostaglandin A1 is a powerful vasodepressor that augments renal blood flow and glomerular filtration and possesses antiplatelet aggregator and oxytocic properties. A continuous intravenous infusion of prostaglandin A1 (40 to 50 micrograms/min) or dihydralazine (35 to 50 micrograms/min) was administered to 20 women with severe preeclampsia (10 in each group). The induced hypotensive response was similar with both drugs but the maximum reduction in blood pressure was achieved sooner with dihydralazine (4 hours) compared with prostaglandin A1 (7.5 hours). The more gradual hypotensive response is probably less dangerous on placental perfusion than a sudden change. Moreover, the oxytocic property of prostaglandin A1 shortened the time to delivery, which constitutes another potential advantage. PMID:2035562

  1. Determination of prostaglandin analogs in cosmetic products by high performance liquid chromatography with tandem mass spectrometry.

    PubMed

    Wittenberg, James B; Zhou, Wanlong; Wang, Perry G; Krynitsky, Alexander J

    2014-09-12

    A method was developed and validated for the determination of 16 prostaglandin analogs in cosmetic products. The QuEChERS (Quick, Easy, Cheap, Efficient, Rugged, Safe) liquid-liquid extraction method, typically used for pesticide residue analysis, was utilized as the sample preparation technique. The prostaglandin analogs were chromatographically separated and quantified using high performance liquid chromatography with tandem mass spectrometry (HPLC-MS/MS). Thirty-one cosmetic products were surveyed, and 13 products were determined to contain a prostaglandin analog with amounts ranging from 27.4 to 297μg/g. The calculated concentrations for the cosmetic products were in a similar range when compared to the concentrations of three different prostaglandin analog-containing prescription products. PMID:25085824

  2. Berberine, an isoquinoline alkaloid, inhibits melanoma cancer cell migration by reducing the expressions of cyclooxygenase-2, prostaglandin E2 and prostaglandin E2 receptors

    PubMed Central

    Singh, Tripti; Vaid, Mudit; Katiyar, Nandan; Sharma, Samriti; Katiyar, Santosh K.

    2011-01-01

    Melanoma is the leading cause of death from skin disease due, in large part, to its propensity to metastasize. We have examined the effect of berberine, an isoquinoline alkaloid, on human melanoma cancer cell migration and the molecular mechanisms underlying these effects using melanoma cell lines, A375 and Hs294. Using an in vitro cell migration assay, we show that over expression of cyclooxygenase (COX)-2, its metabolite prostaglandin E2 (PGE2) and PGE2 receptors promote the migration of cells. We found that treatment of A375 and Hs294 cells with berberine resulted in concentration-dependent inhibition of migration of these cells, which was associated with a reduction in the levels of COX-2, PGE2 and PGE2 receptors (EP2 and EP4). Treatment of cells with celecoxib, a COX-2 inhibitor, or transient transfection of cells with COX-2 small interfering RNA, also inhibited cell migration. Treatment of the cells with 12-O-tetradecanoylphorbol-13-acetate (TPA), an inducer of COX-2 or PGE2, enhanced cell migration, whereas berberine inhibited TPA- or PGE2-promoted cell migration. Berberine reduced the basal levels as well as PGE2-stimulated expression levels of EP2 and EP4. Treatment of the cells with the EP4 agonist stimulated cell migration and berberine blocked EP4 agonist-induced cell migration activity. Moreover, berberine inhibited the activation of nuclear factor-kappa B (NF-κB), an upstream regulator of COX-2, in A375 cells, and treatment of cells with caffeic acid phenethyl ester, an inhibitor of NF-κB, inhibited cell migration. Together, these results indicate for the first time that berberine inhibits melanoma cell migration, an essential step in invasion and metastasis, by inhibition of COX-2, PGE2 and PGE2 receptors. PMID:20974686

  3. [Improved kidney function with intravenous prostaglandin E1 in patients with terminal heart failure].

    PubMed

    Wutte, M; Hülsmann, M; Berger, R; Rödler, S; Frey, B; Stanek, B; Pacher, R

    1998-07-31

    In end stage congestive heart failure activation of a series of compensatory mechanisms increase renal vascular resistance and impair renal function. Prostaglandin E1 is increasingly used in the treatment of severe heart failure for its vasodilating actions. In various experimental settings prostaglandin E analogues are known to improve renal function by modulating renal filtration pressure and redistribution of renal blood flow. However, prostaglandin E1 decreases systemic blood pressure and thus, also renal perfusion pressure, a fact by which renal function might be further compromized in heart failure patients. The aim of the study was to evaluate the effects of prostaglandin E1 on excretory renal function in patients with end stage heart failure and to prove the hypothesis, that the well known local actions of prostaglandins on renal microcirculation might outweigh the negative impact of an expected decrease in perfusion pressure. 25 patients with terminal congestive heart failure were investigated. 13 patients received prostaglandin E1 at a dose of 13.5 +/- 1.9 ng/kg/min in combination with constant rates of dopamine and dobutamine (group A), 12 patients received prostaglandin E1 at a dose of 10.3 +/- 1.7 ng/kg/min without catecholamines (group B). There was no significant difference in prostaglandin dosages between groups. Kidney function was assessed by measuring plasma creatinine and urea nitrogen, urinary output, creatinine clearance, osmotic and free water clearance at baseline and after 72 h of infusion therapy. Hemodynamic parameters were measured by using a balloon tipped pulmonary arterial catheter. Hemodynamic measurements during infusion showed a significant improvement in all patients. At the same time as expected mean arterial pressure decreased in both groups (p < 0.001). Nevertheless, in both groups a significant increase of creatinine clearance during infusion was observed (in group A from 45 ml/min to 78 ml/min., p < 0.05, in group B from 59

  4. Epidermal growth factor modulation of prostaglandins and nitrite biosynthesis in rat fetal membranes.

    PubMed

    Ribeiro, M L; Ogando, D; Farina, M; Franchi, A

    2004-01-01

    The production of prostaglandins (PGs) and nitric oxide (NO) by amnion tissue may play a significant role in parturition. It is thought that epidermal growth factor (EGF) may be one of the fetal signals that governs the initiation of labor. The aim of the present study was to investigate the effect of EGF in vivo on the PGs and nitrite production of rat fetal membranes. We have evaluated the regulation of PGs and nitrite production in rat fetal membranes ex vivo. The intra-uterine administration of EGF 500 ng in day 21 of pregnancy induced increases in PGE(2) (P<0.001) and PGF(2alpha) (P<0.01) compared to the control fetal membranes from pregnant rats on day 22. Also, this dose of EGF diminished nitrate production significantly (P<0.01). We found that fetal membranes at term (days 18-22 of gestation) expressed EGF-R. The NO donor, nitroprussiate 300 and 600 microM, elicited an inhibitory effect on the PGE(2) and PGF(2alpha) stimulated synthesis. On the other hand, indomethacin 10(-6) and 10(-7)M, a non-selective cyclooxygenase inhibitor, reverted the inhibitory effect exerted by EGF. Hence, rat fetal membranes were found to express epidermal growth factor receptors and, under the effect of EGF, PGs and nitrites production pathways interact probably to prevent a toxic effect caused by an exacerbated synthesis of these mediators. PMID:14643177

  5. Mechanism of the Lower Esophageal Sphincter Relaxation ACTION OF PROSTAGLANDIN E1 AND THEOPHYLLINE

    PubMed Central

    Goyal, Raj K.; Rattan, Satish

    1973-01-01

    The intravenous injection of prostaglandin E1 (PGE1) causes a dose-dependent relaxation of the lower esophageal sphincter (LES) in the intact, lightly anesthetized opossum. The action of PGE1 is not inhibited by the drugs that produce muscarinic or nicotinic cholinergic antagonism or alpha and beta adrenergic antagonism in the doses that inhibited the action of respective agonists. Moreover, this action is not affected by exogenous gastrin pentapeptide. The action of PGE1 on the LES is mimicked by isoproterenol, theophylline ethylenediamine, and dibutyryl cyclic AMP. Both theophylline, a phosphodiesterase inhibitor, and isoproterenol, an adenyl cyclase stimulator, added to the action of PGE1. On the other hand, adenyl cyclase inhibitor nicotinic acid, as well as phosphodiesterase stimulator, imidazole inhibited its action. Further, both nicotinic acid and imidazole inhibited the degree of LES relaxation produced by esophageal distension. These studies suggest that intracellular cyclic AMP may act as the “second messenger” in the regulation of the lower esophageal sphincter relaxation. Images PMID:4346007

  6. Studies involving the induction of prostaglandin synthesis following cell transformation by herpes simplex virus type 2

    SciTech Connect

    Krebs, C.R.

    1987-01-01

    The purpose of this study was to determine the effect of HSV-2 transformation on cellular metabolic processes, specifically the metabolism of arachidonic acid (20:4) and prostaglandin (PG) synthesis. Results obtained by labeling cells with (/sup 3/H)20:4 and analyzing the release of radioactivity into overlay culture medium demonstrate that while nontransformed rat embryo fibroblasts (REF) possess phospholipase to catalyze the release of 20:4 from membrane phospholipids, transformation of REF cells by photoinactivated HSV-2 virions induces cyclooxygenase to convert 20:4 substrate primarily to PGE/sub 2/ and PGF/sub 2..cap alpha../. Induction of 20:4 deacylation in nontransformed and HSV-2 transformed cells as well as PG synthesis in transformed cells is further enhanced by the tumor promoter (12-O-tetradecanoylphorbol-13-acetate (TPA) and calcium ionophore A23187. Phospholipase and cyclooxygenase appear to be coupled in their regulation in HSV-2 transformed tumor-derived rat fibrosarcoma (RFS) cells. Three times more (/sup 3/H)20:4 is incorporated into the phosphatidylserine/phosphatidylinositol (PS/PI) fraction in HSV-2 transformed cells compared to REF cells; additionally, this fraction serves as the primary donor of (/sup 3/H)20:4 released from TPA-stimulated transformed cells.

  7. Prostaglandin E2 inhibits collagen synthesis in dermal fibroblasts and prevents hypertrophic scar formation in vivo.

    PubMed

    Zhao, Jingling; Shu, Bin; Chen, Lei; Tang, Jinming; Zhang, Lijun; Xie, Julin; Liu, Xusheng; Xu, Yingbin; Qi, Shaohai

    2016-08-01

    Hypertrophic scarring is a common dermal fibroproliferative disorder characterized by excessive collagen deposition. Prostaglandin E2 (PGE2 ), an important inflammatory product synthesized via the arachidonic acid cascade, has been shown to act as a fibroblast modulator and to possess antifibroblastic activity. However, the mechanism underlying the antifibrotic effect of PGE2 remains unclear. In this study, we explored the effects of PGE2 on TGF-β1-treated dermal fibroblasts in terms of collagen production and to determine the regulatory pathways involved, as well as understand the antiscarring function of PGE2 in vivo. We found that PGE2 inhibited TGF-β1-induced collagen synthesis by regulating the balance of matrix metalloproteinases (MMPs) and tissue inhibitor of metalloproteinase (TIMP). It did so by upregulating cAMP through the E prostanoid (EP)2 receptor. We determined that inhibition of the TGF-β1/Smad pathway by PGE2 is associated with its ability to inhibit collagen synthesis. An in vivo study further confirmed that PGE2 inhibits hypertrophic scar formation by decreasing collagen production. Our results demonstrate that the novel anti-scarring function of PGE2 is achieved by balancing MMPs/TIMP expression and decreasing collagen production. PMID:26997546

  8. Nitric oxide, prostaglandins, and impaired cerebral blood flow autoregulation in group B streptococcal neonatal meningitis.

    PubMed

    Mertineit, C; Samlalsingh-Parker, J; Glibetic, M; Ricard, G; Noya, F J; Aranda, J V

    2000-03-01

    Impaired autoregulation of cerebral blood flow (CBF) contributes to CNS damage during neonatal meningitis. We tested (i) the hypothesis that cerebrovascular autoregulation is impaired during early onset group B streptococcal (GBS) meningitis, (ii) whether this impairment is regulated by vasoactive mediators such as prostaglandins and (or) nitric oxide (NO), and (iii) whether this impairment is preventable by specific and (or) nonspecific inhibitors: dexamethasone, ibuprofen, and Nomega-nitro-L-arginine, a NO inhibitor. Sterile saline or 10(9) colony-forming units (cfu) of heat-killed GBS was injected into the cerebral ventricle of newborn piglets. CBF autoregulation was determined by altering cerebral perfusion pressure (CPP) with balloon-tipped catheters placed in the aorta. GBS produced a narrow range of CBF autoregulation due to an impairment at the upper limit of CPP. We report that in vivo in the early stages (first 2 h) of induced GBS inflammation (i) GBS impairs the upper limit of cerebrovascular autoregulation; (ii) ibuprofen, dexamethasone, and Nomega-nitro-L-arginine not only prevent this GBS-induced autoregulatory impairment but improve the range of cerebrovascular autoregulation; (iii) these autoregulatory changes do not involve circulating cerebral prostanoids; and (iv) the observed changes correlate with the induction of NO synthase gene expression. Thus, acute early onset GBS-induced impairment of the upper limit of CBF autoregulation can be correlated with increases of NO synthase production, suggesting that NO is a vasoactive mediator of CBF. PMID:10721813

  9. Effect of Prostaglandin E2 on Multidrug Resistance Transporters In Human Placental Cells

    PubMed Central

    Lee, Gene T.; Dong, Yafeng; Zhou, Helen; He, Lily; Weiner, Carl P.

    2014-01-01

    Prostaglandin (PG) E2, a major product of cyclooxygenase (COX)-2, acts as an immunomodulator at the maternal-fetal interface during pregnancy. It exerts biologic function through interaction with E-prostanoid (EP) receptors localized to the placenta. The activation of the COX-2/PGE2/EP signal pathway can alter the expression of the ATP-binding cassette (ABC) transporters, multidrug resistance protein 1 [P-glycoprotein (Pgp); gene: ABCB1], and breast cancer resistance protein (BCRP; gene: ABCG2), which function to extrude drugs and xenobiotics from cells. In the placenta, PGE2-mediated changes in ABC transporter expression could impact fetal drug exposure. Furthermore, understanding the signaling cascades involved could lead to strategies for the control of Pgp and BCRP expression levels. We sought to determine the impact of PGE2 signaling mechanisms on Pgp and BCRP in human placental cells. The treatment of placental cells with PGE2 up-regulated BCRP expression and resulted in decreased cellular accumulation of the fluorescent substrate Hoechst 33342. Inhibiting the EP1 and EP3 receptors with specific antagonists attenuated the increase in BCRP. EP receptor signaling results in activation of transcription factors, which can affect BCRP expression. Although PGE2 decreased nuclear factor κ-light chain-enhancer of activated B activation and increased activator protein 1, chemical inhibition of these inflammatory transcription factors did not blunt BCRP up-regulation by PGE2. Though PGE2 decreased Pgp mRNA, Pgp expression and function were not significantly altered. Overall, these findings suggest a possible role for PGE2 in the up-regulation of placental BCRP expression via EP1 and EP3 receptor signaling cascades. PMID:25261564

  10. Effect of prostaglandin E2 on multidrug resistance transporters in human placental cells.

    PubMed

    Mason, Clifford W; Lee, Gene T; Dong, Yafeng; Zhou, Helen; He, Lily; Weiner, Carl P

    2014-12-01

    Prostaglandin (PG) E2, a major product of cyclooxygenase (COX)-2, acts as an immunomodulator at the maternal-fetal interface during pregnancy. It exerts biologic function through interaction with E-prostanoid (EP) receptors localized to the placenta. The activation of the COX-2/PGE2/EP signal pathway can alter the expression of the ATP-binding cassette (ABC) transporters, multidrug resistance protein 1 [P-glycoprotein (Pgp); gene: ABCB1], and breast cancer resistance protein (BCRP; gene: ABCG2), which function to extrude drugs and xenobiotics from cells. In the placenta, PGE2-mediated changes in ABC transporter expression could impact fetal drug exposure. Furthermore, understanding the signaling cascades involved could lead to strategies for the control of Pgp and BCRP expression levels. We sought to determine the impact of PGE2 signaling mechanisms on Pgp and BCRP in human placental cells. The treatment of placental cells with PGE2 up-regulated BCRP expression and resulted in decreased cellular accumulation of the fluorescent substrate Hoechst 33342. Inhibiting the EP1 and EP3 receptors with specific antagonists attenuated the increase in BCRP. EP receptor signaling results in activation of transcription factors, which can affect BCRP expression. Although PGE2 decreased nuclear factor κ-light chain-enhancer of activated B activation and increased activator protein 1, chemical inhibition of these inflammatory transcription factors did not blunt BCRP up-regulation by PGE2. Though PGE2 decreased Pgp mRNA, Pgp expression and function were not significantly altered. Overall, these findings suggest a possible role for PGE2 in the up-regulation of placental BCRP expression via EP1 and EP3 receptor signaling cascades. PMID:25261564

  11. Hematopoetic prostaglandin D synthase: an ESR1-dependent oviductal epithelial cell synthase.

    PubMed

    Bridges, Phillip J; Jeoung, Myoungkun; Shim, Sarah; Park, Ji Yeon; Lee, Jae Eun; Sapsford, Lindsay A; Trudgen, Kourtney; Ko, Chemyong; Gye, Myung Chan; Jo, Misung

    2012-04-01

    Oviductal disease is a primary cause of infertility, a problem that largely stems from excessive inflammation of this key reproductive organ. Our poor understanding of the mechanisms regulating oviductal inflammation restricts our ability to diagnose, treat, and/or prevent oviductal disease. Using mice, our objective was to determine the spatial localization, regulatory mechanism, and functional attributes of a hypothesized regulator of oviductal inflammation, the hematopoietic form of prostaglandin D synthase (HPGDS). Immunohistochemistry revealed specific localization of HPGDS to the oviduct's epithelium. In the isthmus, expression of HPGDS was consistent. In the ampulla, expression of HPGDS appeared dependent upon stage of the estrous cycle. HPGDS was expressed in the epithelium of immature and cycling mice but not in the oviducts of estrogen receptor α knockouts. Two receptor subtypes bind PGD₂: PGD₂ receptor and G protein-coupled receptor 44. Expression of mRNA for Ptgdr was higher in the epithelial cells (EPI) than in the stroma (P < 0.05), whereas mRNA for Gpr44 was higher in the stroma than epithelium (P < 0.05). Treatment of human oviductal EPI with HQL-79, an inhibitor of HPGDS, decreased cell viability (P < 0.05). Treatment of mice with HQL-79 increased mRNA for chemokine (C-C motif) ligands 3, 4, and 19; chemokine (C-X-C motif) ligands 11 and 12; IL-13 and IL-17B; and TNF receptor superfamily, member 1b (P < 0.02 for each mRNA). Overall, these results suggest that HPGDS may play a role in the regulation of inflammation and EPI health within the oviduct. PMID:22374975

  12. Opposing effects of nitric oxide and prostaglandin inhibition on muscle mitochondrial Vo(2) during exercise.

    PubMed

    Boushel, Robert; Fuentes, Teresa; Hellsten, Ylva; Saltin, Bengt

    2012-07-01

    Nitric oxide (NO) and prostaglandins (PG) together play a role in regulating blood flow during exercise. NO also regulates mitochondrial oxygen consumption through competitive binding to cytochrome-c oxidase. Indomethacin uncouples and inhibits the electron transport chain in a concentration-dependent manner, and thus, inhibition of NO and PG synthesis may regulate both muscle oxygen delivery and utilization. The purpose of this study was to examine the independent and combined effects of NO and PG synthesis blockade (L-NMMA and indomethacin, respectively) on mitochondrial respiration in human muscle following knee extension exercise (KEE). Specifically, this study examined the physiological effect of NO, and the pharmacological effect of indomethacin, on muscle mitochondrial function. Consistent with their mechanism of action, we hypothesized that inhibition of nitric oxide synthase (NOS) and PG synthesis would have opposite effects on muscle mitochondrial respiration. Mitochondrial respiration was measured ex vivo by high-resolution respirometry in saponin-permeabilized fibers following 6 min KEE in control (CON; n = 8), arterial infusion of N(G)-monomethyl-L-arginine (L-NMMA; n = 4) and Indo (n = 4) followed by combined inhibition of NOS and PG synthesis (L-NMMA + Indo, n = 8). ADP-stimulated state 3 respiration (OXPHOS) with substrates for complex I (glutamate, malate) was reduced 50% by Indo. State 3 O(2) flux with complex I and II substrates was reduced less with both Indo (20%) and L-NMMA + Indo (15%) compared with CON. The results indicate that indomethacin reduces state 3 mitochondrial respiration primarily at complex I of the respiratory chain, while blockade of NOS by L-NMMA counteracts the inhibition by Indo. This effect on muscle mitochondria, in concert with a reduction of blood flow accounts for in vivo changes in muscle O(2) consumption during combined blockade of NOS and PG synthesis. PMID:22552792

  13. Prostaglandin synthesis by chicken and rat lung microsomes

    SciTech Connect

    Craig-Schmidt, M.C.; Faircloth, S.A.; Wu-Wang, C.Y.

    1986-03-01

    A comparison between chicken and rat lung was made for microsomal prostaglandin (PG) synthesis from 1-/sup 14/C-arachidonic acid. Microsomal protein (2.0 mg) from chicken or rat lung was incubated in the presence of 20 ..mu..g of 1-/sup 14/C-arachidonic acid (specific activity = 3 x 10/sup 6/ dpm/..mu..mol for chicken; 6 x 10/sup 6/ dpm/..mu..mol for rat), 0.05 M Tris-HCl buffer (pH = 8.0), 0.5 mM epinephrine, and 1 mM reduced glutathione in a total volume of 0.5 ml in a 37/sup 0/C water bath with shaking for 15 min. After acidification with 1 M HCl to pH 3, prostaglandins were extracted with ethyl acetate. The products of the reactions were separated by reversed phase chromatography, and the radioactivity of each prostanoid fraction was determined. The predominant prostanoid synthesized by chicken lung microsomes was PGE/sub 2/, followed by much lower amounts of thromboxane B/sub 2/ (TXB/sub 2/), PGF/sub 2//sub ..cap alpha../ and PGD/sub 2/. In at lung, 6-keto-PGF/sub 1//sub ..cap alpha../ was the predominant product formed, with minor amounts of 6-keto-PGE/sub 1/, TXB/sub 2/, PGF/sub 2//sub ..cap alpha../ and PGD/sub 2/. In rat lung, 6-keto-FGF/sub 1//sub ..cap alpha../ was the predominant product formed, with minor amounts of 6-keto-PGF/sub 1//sub ..cap alpha../ was the predominant product formed, with minor amounts of 6-keto-PGE/sub 1/, TXB/sub 2/, PGF/sub 2//sub ..cap alpha../, PGE/sub 2/ and PGD/sub 2/ being formed. Enzyme specific activity (pmol of PG produced per mg microsomal protein per min) was 11.9 for PGE/sub 2/ produced by chicken lung and 16. 7 for 6-keto-P/sub 1//sub ..cap alpha../ produced by rat lung. Thus, there appears to be a species variation in chicken compared to rat for the lung prostanoids which are known to cause bronchial dilation.

  14. Intraocular pressure-lowering combination therapies with prostaglandin analogues.

    PubMed

    Aptel, Florent; Chiquet, Christophe; Romanet, Jean-Paul

    2012-07-01

    Intraocular pressure (IOP) reduction is currently the only therapeutic approach demonstrated to preserve visual function in patients with glaucoma. The first line of glaucoma treatment consists of topical IOP-lowering medications, usually initiated as monotherapy. A significant proportion of patients require more than one medication to reach a target IOP at which optic nerve damage will not progress. As prostaglandin analogues (PGAs) are the most effective class for reducing IOP, one of the other commonly used classes (β-adrenoceptor antagonist [β-blocker], carbonic anhydrase inhibitor or α(2)-adrenoceptor agonist) is frequently combined with a PGA. In the last decade, the use of fixed combinations containing two medications in a single bottle has steadily increased. Fixed combinations have the potential to simplify the dosing regimen, increase patient adherence, avoid the washout effect of the second drop on the first medication instilled, decrease exposure to preservatives and, sometimes, reduce the cost of treatment. Clinical trials have evaluated PGA-based fixed combinations versus unfixed combinations (individual components administered concomitantly) or versus individual monotherapies; however, any advantage that the fixed combinations may have in terms of IOP-lowering efficacy is still debated. For these reasons, the PGA-based fixed combinations are not approved by regulatory authorities in some countries, such as the US. We review the published studies evaluating the efficacy and tolerability of the IOP-lowering unfixed and fixed combination therapies with PGAs. Regarding unfixed combinations, the review shows that α(2)-adrenergic agonists-PGA and carbonic anhydrase inhibitor-PGA combinations seem to be at least as effective at reducing IOP as the β-blocker-PGA combinations. As for the fixed combinations, the review shows that the three PGA-timolol fixed combinations are more effective than their component medications used separately as monotherapy and

  15. Molecular inhibition of prostaglandin E2 with GW627368X: Therapeutic potential and preclinical safety assessment in mouse sarcoma model.

    PubMed

    Parida, Sheetal; Parekh, Aditya; Dey, Goutam; Ghosh, Sukhen C; Mandal, Mahitosh

    2015-01-01

    Prostaglandin E2, the major COX-2 product, acts via 4 functionally distinct prostanoid receptors, EP(1-4). PGE-2, through its receptors, feeds back to positively increase COX-2 expression augmenting its own synthesis thereby driving angiogenesis, while suppressing apoptosis and innate immunity. In addition to the well characterized PGE2/EP4/cAMP/PKA/CREB, EP4 activation increases GSK3 phosphorylation via PI3K and Akt consequently reducing β-catenin phosphorylation. EP4 induces angiogenesis by enhancing VEGF production via ERK activation. These effects of EP4 are asserted either directly or via EGFR transactivation depending on the type of cancer. In view of the safety concerns regarding long term use of COX-2 inhibitors and to find more effective alternatives, we evaluated the potential of EP4 prostanoid receptor as a target for treating cancer progression using a highly selective EP4 antagonist, 4-(4,9-diethoxy-1,3-dihydro-1-oxo-2H-benz[f]isoindol-2-yl)-N-(phenylsulfonyl)-benzeneacetamide. Oral administration of GW627368X showed significant tumor regression characterized by tumor reduction and induction of apoptosis. Reduction in prostaglandin E2 synthesis also led to reduced level of VEGF in plasma. Regulation of multiple pathways downstream of EP4 was evident by down regulation of COX-2, p-Akt, p-MAPK and p-EGFR. Considering wide distribution of the EP4 prostanoid receptor in major organs and the array of physiological processes it contributes to, the safety profile of the drug was analyzed. No major organ toxicity, immunosupression, behavioral change or change in blood parameters attributable to the drug was observed. The results assert the significance of EP4 prostanoid receptor as a therapeutic target as well as the safety of EP4 blockade by GW627368X. PMID:25894216

  16. Prostaglandin E2 causes hypoventilation and apnea in newborn lambs.

    PubMed

    Guerra, F A; Savich, R D; Wallen, L D; Lee, C H; Clyman, R I; Mauray, F E; Kitterman, J A

    1988-05-01

    To test the hypothesis that prostaglandin (PG) E2 is a respiratory depressant in the newborn lamb, 12 chronically catheterized, unanesthetized lambs (age 2-6 days) were infused with progressively increasing doses of PGE2 (0.1, 0.5, 1.0, and 5.0 micrograms.kg-1.min-1; 30 min for each dose) into the ascending aorta. PGE2 caused significant progressive decreases in ventilation (due to decreased tidal volume and breathing rate), heart rate, blood pressure, and percent of the time spent in low-voltage electrocortical activity (LVA). PGE2 also caused respiratory acidosis, hypoxemia, and increased frequency and duration of apneic events (greater than 3 s). During the infusion there was a dose-related increase in plasma concentration of PGE2. At 30 min postinfusion, all measured variables showed recovery, although arterial pH, CO2 tension, and plasma PGE2 remained significantly different from control values, and the percent time in LVA was even higher than during control. Infusion of the vehicle alone (n = 5) caused no significant changes in any of the measured variables. The results, taken in combination with previous fetal studies, indicate that PGE2 has marked inhibitory effects on breathing movements both before and after birth. PMID:3164715

  17. Sequential induction of prostaglandin E and D synthases in inflammation

    SciTech Connect

    Schuligoi, Rufina . E-mail: rufina.schuligoi@meduni-graz.at; Grill, Magdalena; Heinemann, Akos; Peskar, Bernhard A.; Amann, Rainer

    2005-09-30

    Enhanced biosynthesis of prostaglandin (PG)D{sub 2} and subsequent formation of 15-deoxy-{delta}{sup 12,14}-PGJ{sub 2} has been suggested to contribute to resolution of inflammation. The primary aim of the present study in mouse heart was, therefore, to determine at the transcriptional level if there is sequential induction of PGE and PGD synthases (S) during inflammation. Expression of interleukin (IL)-1{beta} in heart was enhanced 4 h after systemic inflammation and declined thereafter within 3-5 days to basal levels. In contrast to cyclooxygenase-2 and membrane-bound (m)-PGES-1, which both peaked 4 h after endotoxin administration, hematopoietic (H)-PGDS expression was enhanced only 48 h after endotoxin. The expression of lipocalin-type (L)-PGDS was not significantly influenced. mRNA encoding the putative target of 15-deoxy-{delta}{sup 12,14}-PGJ{sub 2}, peroxisome proliferator-activated receptor {gamma}, was enhanced between 4 and 24 h after induction of inflammation. Treatment of mice with acetylsalicylic acid or indomethacin at doses effective to cause near-complete inhibition of PGE{sub 2} and PGD{sub 2} biosynthesis in heart ex vivo resulted in enhanced expression of IL-1{beta} 24 h after endotoxin administration. These results provide additional support for the hypothesis of a shift towards PGD{sub 2} biosynthesis during resolution of inflammation.

  18. Influence of prostaglandin E2 on parturition in cattle.

    PubMed

    Hirsbrunner, G; Zanolari, P; Althaus, H; Hüsler, J; Steiner, A

    2007-09-22

    A double-blinded, randomised, placebo-controlled field study of the influence of prostaglandin E2 (PGE2) on cattle at parturition was carried out. The extent of cervical opening and the intensity of labour were scored before administration of the compound and 10 minutes later; routine birth assistance was then continued by the veterinarian. Successful birth occurred more quickly in the cows treated with PGE2. The extent of cervical opening before the administration of the drug had a significant effect on the time to delivery, but the intensity of labour and a concomitant infusion of calcium did not have significant effects on this period. The less open the cervix before administration of the drug, the more the duration of parturition differed between the two groups, with the placebo group taking longer. A telephone follow-up inquiry found no significant differences between the cows postpartum; there were cases of mastitis and hypocalcaemia in both groups. The incidence of retained fetal membranes and the mortality of the calves were higher in the placebo group, but in neither case was the difference significant. PMID:17890770

  19. Prostaglandin E2 Prevents Disuse-Induced Cortical Bone Loss

    NASA Technical Reports Server (NTRS)

    Jee, Webster S. S.; Akamine, T.; Ke, Hua Zhu; Li, Xiao Jian; Tang, L. Y.; Zeng, Q. Q.

    1992-01-01

    The object of this study was to determine whether prostaglandin E2 (PGE2) can prevent disuse (underloaded)-induced cortical bone loss as well as add extra bone to underloaded bones. Thirteen-month-old retired female Sprague-Dawley breeders served as controls or were subjected to simultaneous right hindlimb immobilization by bandaging and daily subcutaneous doses of 0, 1, 3, or 6 mg PGE2/kg/d for two and six weeks. Histomorphometric analyses were performed on double-fluorescent labeled undecalcified tibial shaft sections (proximal to the tibiofibular junction). Disuse-induced cortical bone loss occurred by enlarging the marrow cavity and increasing intracortical porosity. PGE2 treatment of disuse shafts further increased intracortical porosity above that in disuse alone controls. This bone loss was counteracted by enhancement of periosteal and corticoendosteal bone formation. Stimulation of periosteal and corticoendosteal bone formation slightly enlarged the total tissue (cross-sectional) area and inhibited marrow cavity enlargement. These PGE2-induced activities netted the same percentage of cortical bone with a different distribution than the beginning and age related controls. These findings indicate the PGE2-induced increase in bone formation compensated for the disuse and PGE2-induced bone loss, and thus prevented immobilization induced bone loss.

  20. Developmental changes of prostaglandin processing in rat small intestine

    SciTech Connect

    Koldovsky, O.; Bedrick, A.

    1986-03-01

    Cytoprotective prostaglandins are present in milk and can be absorbed intact from the gastrointestinal tract in suckling animals. To examine developmental changes in intestinal metabolism of PGF/sub 2..cap alpha../, everted sacs of small intestinal segments in suckling and weanling rats were prepared. Incubation (60 min) was performed in KRB buffer, pH 7.4 at 37/sup 0/C. Bathing mucosal fluid (MF) contained /sup 3/H-PGF/sub 2..cap alpha../. MF, intestinal wall (IW) and serosal fluid (SF) were analyzed quantitatively for total radioactivity, and qualitatively by organic solvent extraction followed by thin layer chromatography. Changes in MF radioactivity were minimal after incubation. SU had greater capacity for PGF/sub 2..cap alpha../ transfer into SF. Compared to WE, SU had greater proportion of intact, unmetabolized PGF/sub 2..cap alpha../ present in IW of all intestinal segments; i.e., in middle segment: 32.9% +/- 4.5 (mean +/- SEM) vs 17.1% +/- 2.4 (N = 6/group; p < 0.2). WE had more nonpolar PGF/sub 2..cap alpha../ degradation products present. In each age group, chromatographic patterns of IW and SF were similar for each intestinal region. Intestinal everted sacs of SU and WE transfer PGF/sub 2..cap alpha../. SU have a greater proportion and amount of unmetabolized PGF/sub 2..cap alpha../ present in IW and SF than WE. Possible functional significance to the integrity of intestinal mucosal of sucklings has to be considered.

  1. Prostaglandin-E2 Mediated Increase in Calcium and Phosphate Excretion in a Mouse Model of Distal Nephron Salt Wasting

    PubMed Central

    Soleimani, Manoocher; Barone, Sharon; Xu, Jie; Alshahrani, Saeed; Brooks, Marybeth; McCormack, Francis X.; Smith, Roger D.; Zahedi, Kamyar

    2016-01-01

    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 sodium and

  2. Prostaglandin-E2 Mediated Increase in Calcium and Phosphate Excretion in a Mouse Model of Distal Nephron Salt Wasting.

    PubMed

    Soleimani, Manoocher; Barone, Sharon; Xu, Jie; Alshahrani, Saeed; Brooks, Marybeth; McCormack, Francis X; Smith, Roger D; Zahedi, Kamyar

    2016-01-01

    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 sodium and

  3. Upregulation of the EP1 receptor for prostaglandin E2 promotes skin tumor progression.

    PubMed

    Surh, Inok; Rundhaug, Joyce; Pavone, Amy; Mikulec, Carol; Abel, Erika; Fischer, Susan M

    2011-06-01

    Prostaglandin E(2) (PGE(2) ) has been shown to promote the development of murine skin tumors. EP1 is 1 of the 4 PGE(2) G-protein-coupled membrane receptors expressed by murine keratinocytes. EP1 mRNA levels were increased ∼2-fold after topical treatment with 12-O-tetradecanoylphorbol-13-acetate (TPA) or exposure to ultraviolet (UV) light, as well as increased ∼3- to 12-fold in tumors induced by 7,12-dimethyl-benz[a]anthracene (DMBA) initiation/TPA promotion or by UV exposure. To determine the effect of EP1 levels on tumor development, we generated BK5.EP1 transgenic mice that overexpress EP1 in the basal layer of the epidermis. Skins of these mice were histologically indistinguishable from wild type (WT) mice and had similar levels of proliferation after TPA treatment. Using a DMBA/TPA carcinogenesis protocol, BK5.EP1 mice had a reduced tumor multiplicity compared to WT mice, likely due to the observed down-regulation of protein kinase C (PKC). However, the BK5.EP1 mice had an ∼8-fold higher papilloma to carcinoma conversion rate. When DMBA/anthralin was used, BK5.EP1 mice produced more tumors than WT mice, as well as a ninefold increase in carcinomas, indicating that the tumor response is dependent on the type of tumor promoter agent used. Additionally, although almost undetectable in WT mice, cyclooxygenase-2 (COX-2) was expressed in the untreated epidermis of BK5.EP1 mice. While TPA highly induced COX-2 in WT mice, COX-2 expression in the BK5.EP1 mice did not change after TPA treatment; PGE(2) levels were likewise affected. These data indicate that EP1 is more important in tumor progression than in tumor promotion and that it indirectly regulates COX-2 expression. PMID:21268127

  4. Prostaglandin E2/cyclooxygenase pathway in human skeletal muscle: influence of muscle fiber type and age.

    PubMed

    Liu, Sophia Z; Jemiolo, Bozena; Lavin, Kaleen M; Lester, Bridget E; Trappe, Scott W; Trappe, Todd A

    2016-03-01

    Prostaglandin E2 (PGE2) produced by the cyclooxygenase (COX) pathway regulates skeletal muscle protein turnover and exercise training adaptations. The purpose of this study was twofold: 1) define the PGE2/COX pathway enzymes and receptors in human skeletal muscle, with a focus on type I and II muscle fibers; and 2) examine the influence of aging on this pathway. Muscle biopsies were obtained from the soleus (primarily type I fibers) and vastus lateralis (proportionally more type II fibers than soleus) of young men and women (n = 8; 26 ± 2 yr), and from the vastus lateralis of young (n = 8; 25 ± 1 yr) and old (n = 12; 79 ± 2 yr) men and women. PGE2/COX pathway proteins [COX enzymes (COX-1 and COX-2), PGE2 synthases (cPGES, mPGES-1, and mPGES-2), and PGE2 receptors (EP1, EP2, EP3, and EP4)] were quantified via Western blot. COX-1, cPGES, mPGES-2, and all four PGE2 receptors were detected in all skeletal muscle samples examined. COX-1 (P < 0.1) and mPGES-2 were ∼20% higher, while EP3 was 99% higher and EP4 57% lower in soleus compared with vastus lateralis (P < 0.05). Aging did not change the level of skeletal muscle COX-1, while cPGES increased 45% and EP1 (P < 0.1), EP3, and EP4 decreased ∼33% (P < 0.05). In summary, PGE2 production capacity and receptor levels are different in human skeletal muscles with markedly different type I and II muscle fiber composition. In aging skeletal muscle, PGE2 production capacity is elevated and receptor levels are downregulated. These findings have implications for understanding the regulation of skeletal muscle adaptations to exercise and aging by the PGE2/COX pathway and related inhibitors. PMID:26607246

  5. Prostaglandin E2-increased thermosensitivity of anterior hypothalamic neurons is associated with depressed inhibition

    PubMed Central

    Tabarean, Iustin V.; Behrens, M. Margarita; Bartfai, Tamas; Korn, Henri

    2004-01-01

    Temperature responses of anterior hypothalamic neurons are considered key elements in the regulation of the temperature setpoint of homeotherms. We have investigated the sensitivity to warming of cultured neurons of the AH from mice with electrophysiological and immunocytochemical techniques. In control experiments, only ≈9% of the 3- to 5-week-old cells exhibited changes of their basic firing rate when the temperature was raised from 37°C to 40°C. This ratio was increased to 27% after the cultures were “primed” by adding prostaglandin E2 (PGE2), an endogenous pyrogen, in the extracellular medium. In these neurons the firing rate was significantly increased, and the frequency of the gamma γ-aminobutyric acid (GABA) inhibitory postsynaptic potentials was markedly decreased. In contrast, the resting potential and membrane resistance of the recorded cells remained unchanged. PGE2 was found to decrease the level of phosphorylation of the extracellular signal-regulated kinases 1 and 2 in a subset of GABAergic neurons that express the E-prostanoid receptor type 3. Inhibition of ERK1/2 by U0126 mimicked the effects of PGE2. These data indicate that PGE2 acts primarily on the excitability of GABAergic presynaptic cells, most likely via alterations of voltage-gated K+ channels. Our results also suggest that far from being an inherent property of a specialized class of neurons, the degree of thermosensitivity can be strongly modulated by synaptic activity and is a more adaptive property of hypothalamic neurons than previously thought. PMID:14983053

  6. Prostaglandin F2α promotes angiogenesis and embryo-maternal interactions during implantation.

    PubMed

    Kaczynski, Piotr; Kowalewski, M P; Waclawik, Agnieszka

    2016-05-01

    Implantation in humans and other mammals is a critical period during which high embryonic mortality rates occur. Prostaglandins (PGs) are key mediators regulating interactions between the reproductive tract and the conceptus (embryo with extraembryonic membranes). Although the significance of PGF2α as a regulator of corpus luteum regression is well established, the role of its high amounts in the uterine lumen in most mammals, regardless of placentation type, during the implantation period remains unresolved. We hypothesized that PGF2α acting as an embryonic signal mediator contributes to pregnancy establishment. Using a porcine model, we demonstrated that the conceptus and its signal (estradiol-17β) elevated endometrial expression of PGF2α receptor (PTGFR) in vivo and in vitro PTGFR protein was expressed mainly in luminal epithelial (LE) and glandular epithelial cells and blood vessels in the endometrium. PGF2α stimulated the MAPK1/3 pathway in endometrial LE cells that coincided with elevated gene expression and secretion of endometrial vascular endothelial growth factor A (VEGFA) protein. PGF2α-PTGFR and adenylyl cyclase signaling were involved in this process. PGF2α-induced VEGFA acting through its receptors stimulated proliferation of endometrial endothelial cells. Moreover, PGF2α elevated gene expression of biglycan, matrix metalloproteinase 9, transforming growth factor β3, and interleukin 1α in the endometrium. In summary, our study indicates that PGF2α participates in pregnancy establishment by promoting angiogenesis and expression of genes involved in tissue remodeling and conceptus-maternal interactions in porcine endometrium during early pregnancy. PMID:26908918

  7. Prostaglandin E2 promotes proliferation of skeletal muscle myoblasts via EP4 receptor activation

    PubMed Central

    Mo, Chenglin; Zhao, Ruonan; Vallejo, Julian; Igwe, Orisa; Bonewald, Lynda; Wetmore, Lori; Brotto, Marco

    2015-01-01

    We recently demonstrated that conditioned media (CM) from osteocytes enhances myogenic differentiation of myoblasts, suggesting that signaling from bone may be important for skeletal muscle myogenesis. The effect of CM was closely mimicked by prostaglandin E2 (PGE2), a bioactive lipid mediator in various physiological or pathological conditions. PGE2 is secreted at high levels by osteocytes and such secretion is further enhanced under loading conditions. Although four types of receptors, EP1 to EP4, mediate PGE2 signaling, it is unknown whether these receptors play a role in myogenesis. Therefore, in this study, the expression of EPs in mouse primary myoblasts was characterized, followed by examination of their roles in myoblast proliferation by treating myoblasts with PGE2 or specific agonists. All four PGE2 receptor mRNAs were detectable by quantitative real-time PCR (qPCR), but only PGE2 and EP4 agonist CAY 10598 significantly enhance myoblast proliferation. EP1/EP3 agonist 17-phenyl trinor PGE2 (17-PT PGE2) and EP2 agonist butaprost did not have any significant effects. Moreover, treatment with EP4 antagonist L161,982 dose-dependently inhibited myoblast proliferation. These results were confirmed by cell cycle analysis and the gene expression of cell cycle regulators. Concomitant with the inhibition of myoblast proliferation, treatment with L161,982 significantly increased intracellular reactive oxygen species (ROS) levels. Cotreatment with antioxidant N-acetyl cysteine (NAC) or sodium ascorbate (SA) successfully reversed the inhibition of myoblast proliferation and ROS overproduction caused by L161,982. Therefore, PGE2 signaling via the EP4 receptor regulates myogenesis by promoting myoblast proliferation and blocking this receptor results in increased ROS production in myoblasts. PMID:25785867

  8. Synthesis and reception of prostaglandins in corpora lutea of domestic cat and lynx.

    PubMed

    Zschockelt, Lina; Amelkina, Olga; Siemieniuch, Marta J; Kowalewski, Mariusz P; Dehnhard, Martin; Jewgenow, Katarina; Braun, Beate C

    2016-08-01

    Felids show different reproductive strategies related to the luteal phase. Domestic cats exhibit a seasonal polyoestrus and ovulation is followed by formation of corpora lutea (CL). Pregnant and non-pregnant cycles are reflected by diverging plasma progesterone (P4) profiles. Eurasian and Iberian lynxes show a seasonal monooestrus, in which physiologically persistent CL (perCL) support constantly elevated plasma P4 levels. Prostaglandins (PGs) represent key regulators of reproduction, and we aimed to characterise PG synthesis in feline CL to identify their contribution to the luteal lifespan. We assessed mRNA and protein expression of PG synthases (PTGS2/COX2, PTGES, PGFS/AKR1C3) and PG receptors (PTGER2, PTGER4, PTGFR), and intra-luteal levels of PGE2 and PGF2α Therefore, CL of pregnant (pre-implantation, post-implantation, regression stages) and non-pregnant (formation, development/maintenance, early regression, late regression stages) domestic cats, and prooestrous Eurasian (perCL, pre-mating) and metoestrous Iberian (perCL, freshCL, post-mating) lynxes were investigated. Expression of PTGS2/COX2, PTGES and PTGER4 was independent of the luteal stage in the investigated species. High levels of luteotrophic PGE2 in perCL might be associated with persistence of luteal function in lynxes. Signals for PGFS/AKR1C3 expression were weak in mid and late luteal stages of cats but were absent in lynxes, concomitant with low PGF2α levels in these species. Thus, regulation of CL regression by luteal PGF2α seems negligible. In contrast, expression of PTGFR was evident in nearly all investigated CL of cat and lynxes, implying that luteal regression, e.g. at the end of pregnancy, is triggered by extra-luteal PGF2α. PMID:27222595

  9. Prostaglandin E2 promotes proliferation of skeletal muscle myoblasts via EP4 receptor activation.

    PubMed

    Mo, Chenglin; Zhao, Ruonan; Vallejo, Julian; Igwe, Orisa; Bonewald, Lynda; Wetmore, Lori; Brotto, Marco

    2015-01-01

    We recently demonstrated that conditioned media (CM) from osteocytes enhances myogenic differentiation of myoblasts, suggesting that signaling from bone may be important for skeletal muscle myogenesis. The effect of CM was closely mimicked by prostaglandin E2 (PGE2), a bioactive lipid mediator in various physiological or pathological conditions. PGE2 is secreted at high levels by osteocytes and such secretion is further enhanced under loading conditions. Although four types of receptors, EP1 to EP4, mediate PGE2 signaling, it is unknown whether these receptors play a role in myogenesis. Therefore, in this study, the expression of EPs in mouse primary myoblasts was characterized, followed by examination of their roles in myoblast proliferation by treating myoblasts with PGE2 or specific agonists. All four PGE2 receptor mRNAs were detectable by quantitative real-time PCR (qPCR), but only PGE2 and EP4 agonist CAY 10598 significantly enhance myoblast proliferation. EP1/EP3 agonist 17-phenyl trinor PGE2 (17-PT PGE2) and EP2 agonist butaprost did not have any significant effects. Moreover, treatment with EP4 antagonist L161,982 dose-dependently inhibited myoblast proliferation. These results were confirmed by cell cycle analysis and the gene expression of cell cycle regulators. Concomitant with the inhibition of myoblast proliferation, treatment with L161,982 significantly increased intracellular reactive oxygen species (ROS) levels. Cotreatment with antioxidant N-acetyl cysteine (NAC) or sodium ascorbate (SA) successfully reversed the inhibition of myoblast proliferation and ROS overproduction caused by L161,982. Therefore, PGE2 signaling via the EP4 receptor regulates myogenesis by promoting myoblast proliferation and blocking this receptor results in increased ROS production in myoblasts. PMID:25785867

  10. A facile reproducible radioimmunoassay of the mixed metabolites of prostaglandins E, suitable for measurement of relative differences of phospholipase/prostaglandin synthetase activity in vivo.

    PubMed

    Fretland, D J; Cammarata, P S

    1984-04-01

    A relatively simple, reproducible, radioimmunoassay for the mixed metabolites of prostaglandins E (U-PGE-M) in rat and human urine is described. Results of the assay of treated versus control urine extracts correlate well with differences expected from treatments known to alter in vivo phospholipase/prostaglandin synthetase activity. Cross-reactivity of heterogeneous metabolite antiserum with 5 available endogenous prostaglandins and a single metabolite was determined and showed little or no cross reaction. Sensitivity, within-assay precision, interassay reproducibility, and parallelism were also determined and found acceptable. Excretion rates of U-PGE-M by rats and humans were determined, and statistically significant differences could be shown, although absolute values were smaller than estimated absolute values obtained from mass-spectrometric measurements of single, purified metabolites. Normal human male excretion rates differed significantly from those of females. Injection of prostaglandin E1 caused a significant rise in U-PGE-M excretion in rats whereas aspirin and indomethacin caused it to fall. U-PGE-M excretion rates of spontaneous hypertensive rats were significantly less than rates of normotensive controls. Adrenalectomy resulted in excretion of significantly larger amounts of U-PGE-M than in normal or sham-operated controls. A screen of clinically active pharmacological agents and hormones gave results consistent with previously published reports. PMID:6427792

  11. Stage-dependent reduction in T colony formation in Hodgkin's disease. Coincidence with monocyte synthesis of prostaglandins.

    PubMed Central

    Bockman, R S

    1980-01-01

    Prostaglandin synthesis and T lymphocyte colony formation have been examined in previously untreated patients with Hodgkin's disease. Mononuclear cells have been isolated from peripheral blood and spleens of these patients. Significant augmentation in prostaglandin E levels were noted in the mononuclear cell cutures from Hodgkin's disease patients compared with controls (1.64 +/- 0.29 vs. 0.39 +/- 0.09 ng/10(6) cells, P < 0.005). Measured prostaglandin E levels increased with advancing stage of disease. Virtually all of the prostaglandins were synthesized by the adherent monocyte cell population. Prostaglandin E was the major product. Clonal expansion of a T lymphocyte precursor cell, which gives rise to colonies > 50 cells, was determined by a layered soft agar method. T colony formation was significantly reduced in patients with stage II, III, and IV disease. There were progressively reduced colony numbers seen with advancing stage of disease (609 +/- 209, 416 +/- 158, 207 +/- 58 compared with normals 2,274 +/- 360 colonies/10(6) cells plated; P < 0.005). The addition of inhibitors of endogenous prostaglandin synthesis resulted in significant augmentation of T colony number. However, a consistent relative decrease in T colony number was seen even when endogenous prostaglandin E synthesis was blocked. It would appear that both the prostaglandin-dependent and independent T colony precursor cells are lost with progressive stage of disease. A causative role of augmented prostaglandin synthesis in this stage-dependent reduction of T colony formation could not be established. PMID:6967491

  12. Long-term anabolic effects of prostaglandin-E2 on tibial diaphyseal bone in male rats

    NASA Technical Reports Server (NTRS)

    Jee, Webster S. S.; Ke, Hua Zhu; Li, Xiao Jian

    1991-01-01

    The effects of long-term prostaglandin E2 (PGE2) on tibial diaphyseal bone were studied in 7-month-old male Sprague-Dawley rats given daily subcutaneous injections of 0, 1, 3 and 6 mg PGE2/kg/day for 60, 120 and 180 days. The tibial shaft was measured by single photon absorptiometry and dynamic histomorphometric analyses were performed on double-fluorescent labeled undecalcified tibial diaphyseal bone samples. Exogenous PGE2 administration produced the following transient changes in a dose-response manner between zero and 60 days: (1) increased bone width and mineral density; (2) increased total tissue and total bone areas; (3) decreased marrow area; (4) increased periosteal and corticoendosteal lamellar bone formation; (5) activated corticoendosteal lamellar and woven trabecular bone formation; and (6) activated intracortical bone remodeling. A new steady-state of increased tibial diaphyseal bone mass and elevated bone activities were observed from day 60 onward. The elevated bone mass level attained after 60 days of PGE2 treatment was maintained at 120 and 180 days. These observations indicate that the powerful anabolic effects of PGE2 will increase both periosteal and corticoendosteal bone mass and sustain the transient increase in bone mass with continuous daily administration of PGE2.

  13. Inhibition of 15-hydroxy prostaglandin dehydrogenase and increase of prostaglandin E2: effect of sofalcone on rat gastric mucosa.

    PubMed

    Muramatsu, M; Tanaka, M; Murakami, S; Aihara, H

    1987-07-20

    The effect of sofalcone, an anti-ulcer agent, on gastric mucosal prostaglandin (PG) metabolism was studied. Gastric mucosal PGE2 was determined in rats in which PGE2 synthesis was inhibited by preadministration of indomethacin. Oral administration of sofalcone at doses of 200 and 400 mg/kg significantly inhibited the PG metabolizing enzyme, 15-hydroxy-PG-dehydrogenase (15-OH-PG-DH) activity and increased PGE2 contents in the rat gastric mucosa. The inhibition of 15-OH-PG-DH activity was accompanied by an increase of PGE2 contents up to 6 hours after the administration of sofalcone. These changes, however, were not observed 12 hours after its administration. Intraperitoneally administered sofalcone also inhibited 15-OH-PG-DH activity and increased PGE2 content. The inhibition of 15-OH-PG-DH activity by sofalcone was noncompetitive and uncompetitive against substrates NAD and PGE1, respectively. These results suggest that the increase of the gastric PGE2 level is mainly due to the inhibition of 15-OH-PG-DH activity, and this increase in PGE2 may be involved in the anti-ulcer effect of sofalcone. PMID:3474485

  14. Inhibition of prostaglandin synthesis after metabolism of menadione by cultured porcine endothelial cells.

    PubMed Central

    Barchowsky, A; Tabrizi, K; Kent, R S; Whorton, A R

    1989-01-01

    We have examined the effects of menadione on porcine aortic endothelial cell prostaglandin synthesis. Addition of 1-20 microM menadione caused a dose- and time-dependent inhibition of stimulated prostaglandin synthesis with an IC50 of 5 microM at 15 min. Concentrations greater than 100 microM menadione were necessary to increase 51Cr release from prelabeled cells. Recovery of enzyme inactivated by menadione required a 6-h incubation in 1% serum. In a microsomal preparation, menadione was shown to have no direct effect on conversion of arachidonic acid to prostaglandins. In intact cells menadione caused only a 40% inhibition of the conversion of PGH2 to prostacyclin. Enzymes involved in the incorporation and the release of arachidonic acid were not affected by menadione (20 microM, 15 min). Menadione undergoes oxidation/reduction reactions in intact cells leading to partial reduction of oxygen-forming, reactive oxygen species. In our cells menadione was found to increase KCN-resistant oxygen consumption. Further, an increased accumulation of H2O2 was observed with a time course consistent with menadione-induced inhibition of prostaglandin synthesis. We conclude that menadione at sublethal doses caused inhibition of prostaglandin synthesis. The mechanism involves inactivation of PGH2 synthase by a reactive species resulting from metabolism of menadione by endothelial cells. PMID:2495300

  15. Prostaglandin D2 toxicity in primary neurons is mediated through its bioactive cyclopentenone metabolites

    PubMed Central

    Liu, Hao; Li, Wenjin; Rose, Marie E.; Pascoe, Jordan L.; Miller, Tricia M.; Ahmad, Muzamil; Poloyac, Samuel M.; Hickey, Robert W.; Graham, Steven H.

    2014-01-01

    Prostaglandin D2 (PGD2) is the most abundant prostaglandin in brain but its effect on neuronal cell death is complex and not completely understood. PGD2 may modulate neuronal cell death via activation of DP receptors or its metabolism to the cyclopentenone prostaglandins (CyPGs) PGJ2, Δ12-PGJ2 and 15-deoxy-Δ12,14-PGJ2, inducing cell death independently of prostaglandin receptors. This study aims to elucidate the effect of PGD2 on neuronal cell death and its underlying mechanisms. PGD2 dose-dependently induced cell death in rat primary neuron-enriched cultures in concentrations of ≥ 10 μM, and this effect was not reversed by treatment with either DP1 or DP2 receptor antagonists. Antioxidants N-acetylcysteine (NAC) and glutathione which contain sulfhydryl groups that can bind to CyPGs, but not ascorbate or tocopherol, attenuated PGD2-induced cell death. Conversion of PGD2 to CyPGs was detected in neuronal culture medium; treatment with these CyPG metabolites alone exhibited effects similar to those of PGD2, including apoptotic neuronal cell death and accumulation of ubiquitinated proteins. Disruption of lipocalin-type prostaglandin D synthase (L-PGDS) protected neurons against hypoxia. These results support the hypothesis that PGD2 elicits its cytotoxic effects through its bioactive CyPG metabolites rather than DP receptor activation in primary neuronal culture. PMID:23973622

  16. BVDV alters uterine prostaglandin production during pregnancy recognition in cows.

    PubMed

    Cheng, Zhangrui; Abudureyimu, Ayimuguli; Oguejiofor, Chike F; Ellis, Rebekah; Barry, Amy Teresa; Chen, Xing; Anstaett, Olivia L; Brownlie, Joe; Wathes, D Claire

    2016-06-01

    Embryonic mortality in cows is at least in part caused by failure of pregnancy recognition (PR). Evidence has shown that bovine viral diarrhoea virus (BVDV) infection can disrupt pregnancy. Prostaglandins (PG) play important roles in many reproductive processes, such as implantation. The aim of this study was to investigate the effect of BVDV infection on uterine PG production and PR using an in vitro PR model. Bovine uterine endometrial cells isolated from ten BVDV-free cows were cultured and treated with 0 or 100ng/mL interferon-τ (IFNT) in the absence or presence of non-cytopathic BVDV (ncpBVDV). PGF2α and PGE2 concentrations in the spent medium were measured using radioimmunoassays, and in the treated cells expression of the genes associated with PG production and signalling was quantified using qPCR. The results showed that the IFNT challenge significantly stimulated PTGS1 and PTGER3 mRNA expression and PGE2 production; however, these stimulatory effects were neutralised in the presence of ncpBVDV infection. ncpBVDV infection significantly increased PTGS1 and mPGES1 mRNA expression and decreased AKR1B1 expression, leading to increased PGE2 and decreased PGF2α concentrations and an increased PGE2:PGF2α ratio. The other tested genes, including PGR, ESR1, OXTR, PTGS2, PTGER2 and PTGFR, were not significantly altered by IFNT, ncpBVDV or their combination. Our study suggests that BVDV infection may impair PR by (1) inhibiting the effect of IFNT on uterine PG production and (2) inducing an endocrine switch of PG production from PGF2α to PGE2 to decrease uterine immunity, thereby predisposing the animals to uterine disease. PMID:26952097

  17. Reversal of Myofibroblast Differentiation by Prostaglandin E2

    PubMed Central

    Garrison, Garth; Huang, Steven K.; Okunishi, Katsuhide; Scott, Jacob P.; Kumar Penke, Loka Raghu; Scruggs, Anne M.

    2013-01-01

    Differentiation of fibroblasts into α-smooth muscle actin (SMA)–expressing myofibroblasts represents a critical step in the pathogenesis of fibrotic disorders, and is generally regarded as irreversible. Prostaglandin E2 (PGE2) has been shown to prevent multiple aspects of fibroblast activation, including the differentiation of fibroblasts to myofibroblasts. Here, we investigated its ability to reverse this differentiated phenotype. Fetal and adult lung fibroblasts were induced to differentiate into myofibroblasts by 24-hour culture with transforming growth factor (TGF)-β1 or endothelin-1. Cells were then treated without or with PGE2 for various intervals and assessed for α-SMA expression. In the absence of PGE2 treatment, α-SMA expression induced by TGF-β1 was persistent and stable for up to 8 days. By contrast, PGE2 treatment effected a dose-dependent decrease in α-SMA and collagen I expression that was observed 2 days after PGE2 addition, peaked at 3 days, and persisted through 8 days in culture. This effect was not explained by an increase in myofibroblast apoptosis, and indeed, reintroduction of TGF-β1 2 days after addition of PGE2 prompted dedifferentiated fibroblasts to re-express α-SMA, indicating redifferentiation to myofibroblasts. This effect of PGE2 was associated with inhibition of focal adhesion kinase signaling, and a focal adhesion kinase inhibitor was also capable of reversing myofibroblast phenotype. These data unambiguously demonstrate reversal of established myofibroblast differentiation. Because many patients have established or even advanced fibrosis by the time they seek medical attention, this capacity of PGE2 has the potential to be harnessed for therapy of late-stage fibrotic disorders. PMID:23470625

  18. Prostaglandin D2-loaded microspheres effectively activate macrophage effector functions.

    PubMed

    Pereira, Priscilla Aparecida Tartari; Bitencourt, Claudia da Silva; dos Santos, Daiane Fernanda; Nicolete, Roberto; Gelfuso, Guilherme Martins; Faccioli, Lúcia Helena

    2015-10-12

    Biodegradable lactic-co-glycolic acid (PLGA) microspheres (MS) improve the stability of biomolecules stability and allow enable their sustained release. Lipid mediators represent a strategy for improving host defense; however, most of these mediators, such as prostaglandin D2 (PGD2), have low water solubility and are unstable. The present study aimed to develop and characterize MS loaded with PGD2 (PGD2-MS) to obtain an innovative tool to activate macrophages. PGD2-MS were prepared using an oil-in-water emulsion solvent extraction-evaporation process, and the size, zeta potential, surface morphology and encapsulation efficiency were determined. It was also evaluated in vitro the phagocytic index, NF-κB activation, as well as nitric oxide and cytokine production by alveolar macrophages (AMs) in response to PGD2-MS. PGD2-MS were spherical with a diameter of 5.0±3.3 μm and regular surface, zeta potential of -13.4±5.6 mV, and 36% of encapsulation efficiency, with 16-26% release of entrapped PGD2 at 4 and 48 h, respectively. PGD2-MS were more efficiently internalized by AMs than unloaded-MS, and activated NF-κB more than free PGD2. Moreover, PGD2-MS stimulated the production of nitric oxide, TNF-α, IL-1β, and TGF-β, more than free PGD2, indicating that microencapsulation increased the activating effect of PGD2 on cells. In LPS-pre-treated AMs, PGD2-MS decreased the release of IL-6 but increased the production of nitric oxide and IL-1β. These results show that the morphological characteristics of PGD2-MS facilitated interaction with, and activation of phagocytic cells; moreover, PGD2-MS retained the biological activities of PGD2 to trigger effector mechanisms in AMs. It is suggested that PGD2-MS represent a strategy for therapeutic intervention in the lungs of immunocompromised subjects. PMID:26143263

  19. Opposing roles of Prostaglandin D2 receptors in ulcerative colitis

    PubMed Central

    Sturm, Eva M.; Radnai, Balazs; Jandl, Katharina; Stančić, Angela; Parzmair, Gerald P.; Högenauer, Christoph; Kump, Patrizia; Wenzl, Heimo; Petritsch, Wolfgang; Pieber, Thomas R.; Schuligoi, Rufina; Marsche, Gunther; Ferreirós, Nerea; Heinemann, Akos; Schicho, Rudolf

    2014-01-01

    Pro-resolution functions were reported for Prostaglandin D2 (PGD2) in colitis, but the role of its two receptors, DP and in particular CRTH2 are less well defined. We investigated DP and CRTH2 expression and function during human and murine ulcerative colitis (UC). Expression of receptors was measured by flow cytometry on peripheral blood leukocytes, and by immunohistochemistry and immunoblotting in colon biopsies of patients with active UC and healthy individuals. Receptor involvement in UC was evaluated in a mouse model of DSS colitis. DP and CRTH2 expression changed in leukocytes of patients with active UC in a differential manner. In UC patients, DP showed higher expression in neutrophils but lower in monocytes as compared to control subjects. In contrast, CRTH2 was decreased in eosinophils, NK and CD3+ T cells but not in monocytes and CD3+/CD4+ T cells. The decrease of CRTH2 on blood eosinophils clearly correlated with disease activity. DP correlated positively with disease activity in eosinophils but inversely in neutrophils. CRTH2 internalized upon treatment with PGD2 and 11-dehydroTXB2 in eosinophils of controls. Biopsies of UC patients revealed an increase of CRTH2-positive cells in the colonic mucosa and high CRTH2 protein content. The CRTH2 antagonist CAY10595 improved while the DP antagonist MK0524 worsened inflammation in murine colitis. DP and CRTH2 play differential roles in UC. Although expression of CRTH2 on blood leukocytes is downregulated in UC, CRTH2 is present in colon tissue where it may contribute to inflammation whereas DP likely promotes anti-inflammatory actions. PMID:24929001

  20. Attenuation of nitric oxide- and prostaglandin-independent vasodilation of retinal arterioles induced by acetylcholine in streptozotocin-treated rats.

    PubMed

    Nakazawa, Taisuke; Kaneko, Yoshiko; Mori, Asami; Saito, Maki; Sakamoto, Kenji; Nakahara, Tsutomu; Ishii, Kunio

    2007-03-01

    Diabetes alters retinal hemodynamics, but little is known about the impact of diabetes on the role of endothelium-derived hyperpolarizing factor (EDHF) in the regulation of retinal circulation. Therefore, we examined how diabetes affects the nitric oxide- and prostaglandin-independent vasodilation of retinal arterioles induced by acetylcholine. Male Wistar rats were treated with streptozotocin (80 mg/kg, i.p.) and experiments were performed 6-8 weeks later. Under artificial ventilation, rats were treated with tetrodotoxin (100 microg/kg, i.v.) to eliminate any nerve activity and prevent movement of the eye. Methoxamine was used to maintain adequate systemic circulation. Fundus images were captured by a digital camera that was equipped with a special objective lens. The vasodilator responses of retinal arterioles were assessed by measuring changes in diameters of the vessels. In streptozotocin-induced diabetic rats and the age-matched controls, acetylcholine increased diameters of retinal arterioles in a dose-dependent manner. The vasodilator responses to acetylcholine in diabetic rats were smaller than those in control rats. The nitric oxide- and prostaglandin-independent vasodilation of retinal arterioles observed under treatment with combination of N(G)-nitro-l-arginine methyl ester (30 mg/kg, i.v.) and indomethacin (5 mg/kg, i.v.) were also attenuated by diabetes. Diabetes did not alter the dilator responses of retinal arterioles to sodium nitroprusside and forskolin. These results suggest that diabetes impairs EDHF-mediated vasodilation of retinal arterioles induced by acetylcholine. The impaired EDHF-mediated vasodilation may contribute to alteration of retinal hemodynamics in diabetes. PMID:17079193

  1. L-Citrulline dilates rat retinal arterioles via nitric oxide- and prostaglandin-dependent pathways in vivo.

    PubMed

    Mori, Asami; Morita, Masahiko; Morishita, Koji; Sakamoto, Kenji; Nakahara, Tsutomu; Ishii, Kunio

    2015-04-01

    L-Citrulline is an effective precursor of L-arginine produced by the L-citrulline/L-arginine cycle, and it exerts beneficial effects on the cardiovascular system by supporting enhanced nitric oxide (NO) production. NO dilates retinal blood vessels via the cyclooxygenase-mediated pathway. The purpose of this study was to examine the effects of L-citrulline on retinal circulation and to investigate the potential involvement of NO and prostaglandins in L-citrulline-induced responses in rats. L-Citrulline (10-300 μg kg(-1) min(-1), i.v.) increased the diameter of retinal arterioles without significantly changing mean blood pressure, heart rate, and fundus blood flow. The vasodilator response of retinal arterioles to l-citrulline was significantly diminished following treatment with N(G)-nitro-L-arginine methyl ester (30 mg/kg, i.v.), an NO synthase inhibitor, or indomethacin (5 mg/kg, i.v.), a cyclooxygenase inhibitor. In addition, α-methyl-dl-aspartic acid (147 mg/kg, i.v.), an inhibitor of argininosuccinate synthase, the rate-limiting enzyme for the recycling of l-citrulline to l-arginine, diminished the L-citrulline-induced retinal vasodilation. These results suggest that both NO- and prostaglandin-dependent pathways contribute to the L-citrulline-induced vasodilation of rat retinal arterioles. The L-citrulline/L-arginine recycling pathway may have more importance in regulating vascular tone in retinal blood vessels than in peripheral resistance vessels. PMID:25953269

  2. Upregulation of Cyclooxygenase-2/Prostaglandin E2 (COX-2/PGE2) Pathway Member Multiple Drug Resistance-Associated Protein 4 (MRP4) and Downregulation of Prostaglandin Transporter (PGT) and 15-Prostaglandin Dehydrogenase (15-PGDH) in Triple-Negative Breast Cancer

    PubMed Central

    Kochel, Tyler J.; Goloubeva, Olga G.; Fulton, Amy M.

    2016-01-01

    Elevated levels of cyclooxygenase-2 (COX-2) and prostaglandin E2 (PGE2) are indicators of a poor prognosis in breast cancer. Using several independent publicly available breast cancer gene expression databases, we investigated other members of the PGE2 pathway. PGE2 is produced by COX-2 and actively exported by multiple drug resistance-associated protein 4 (MRP4) into the extracellular microenvironment, where PGE2 can bind four cognate EP receptors (EP1–EP4) and initiate diverse biological signaling pathways. Alternatively, PGE2 is imported via the prostaglandin transporter (PGT) and metabolized by 15-prostaglandin dehydrogenase (15-PGDH/HPGD). We made the novel observation that MRP4, PGT, and 15-PGDH are differentially expressed among distinct breast cancer molecular subtypes; this finding was confirmed in independent datasets. In triple-negative breast cancer, the observed gene expression pattern (high COX-2, high MRP4, low PGT, and low 15-PGDH) would favor high levels of tumor-promoting PGE2 in the tumor microenvironment that may contribute to the overall poor prognosis of triple-negative breast cancer. PMID:27257388

  3. Kinetic Evidence for the Presence of Two Postaglandin Receptor Sites Regulating the Activity of Intestinal Adenylate Cyclase Sensitive to Escherichia coli Enterotoxin

    PubMed Central

    Kantor, Harvey S.; Tao, Pearl; Kiefer, Helen Chilton

    1974-01-01

    Kinetic behavior most consistent with the presence of two independent, but simultaneously acting, regulatory effector sites for prostaglandins has been presented for adenylate cyclase (EC 4.6.1.1) of rabbit intestinal epithelial cells. One site regulates activation of the catalytic site, while the other site regulates inhibition. A synthetic prostaglandin analogue, 7-oxa-13-prostynoic acid, is recognized at both sites in a concentration-dependent manner. At concentrations of 7-oxa-13-prostynoic acid less than 45 μg/ml, activation is seen, while at higher concentrations, inhibition is seen. Different naturally occurring prostaglandins appear to be site-specific. Prostaglandin E1 gives only activation of the cyclase, while prostaglandin A1 gives only inhibition of the activated cyclase. When saturating concentrations of prostaglandin E1 are used to activate adenylate cyclase, no further activation by 7-oxa-13-prostynoic acid can be elicited, indicating that both molecules activate at the same site. The similarity of inhibition constants for both 7-oxa-13-prostynoic acid and prostaglandin A1 suggests that the mode of binding is the same for both compounds and that they probably inhibit by acting at the same site. The inhibition by 7-oxa-13-prostynoic acid and by prostaglandin A1 overrides enzyme activation produced by either Escherichia coli enterotoxin, prostaglandin E1, or sodium fluoride, suggesting that in intestinal adenylate cyclase this site is the primary regulatory site (i.e., primary allosteric effector site) for enzyme activity. These data suggest that sites exist on adenylate cyclase which would allow prostaglandins to serve as the intracellular messengers by which the cell controls its adenylate-cyclase-mediated response to extracellular stimulation, as with hormones. PMID:4208548

  4. Overexpressed TRPV3 ion channels in skin keratinocytes modulate pain sensitivity via prostaglandin E2

    PubMed Central

    Huang, Susan M.; Lee, Hyosang; Chung, Man-Kyo; Park, Una; Yu, Yin Yin; Bradshaw, Heather B.; Coulombe, Pierre A.; Walker, J. Michael; Caterina, Michael J.

    2009-01-01

    The ability to sense changes in the environment is essential for survival because it permits responses such as withdrawal from noxious stimuli and regulation of body temperature. Keratinocytes, which occupy much of the skin epidermis, are situated at the interface between the external environment and the body's internal milieu, and have long been appreciated for their barrier function against external insults. The recent discovery of temperature-sensitive TRPV ion channels in keratinocytes has raised the possibility that these cells also actively participate in acute temperature and pain sensation. To address this notion, we generated and characterized transgenic mice that overexpress TRPV3 in epidermal keratinocytes under the control of the keratin 14 promoter. Compared to wild-type controls, keratinocytes overexpressing TRPV3 exhibited larger currents as well as augmented prostaglandin E2 (PGE2) release in response to two TRPV3 agonists, 2-aminoethoxydiphenyl borate (2APB) and heat. Thermal selection behavior and heat-evoked withdrawal behavior of naïve mice overexpressing TRPV3 were not consistently altered. Upon selective pharmacological inhibition of TRPV1 with JNJ-7203212, however, the keratinocyte-specific TRPV3 transgenic mice showed increased escape responses to noxious heat relative to their wild-type littermates. Co-administration of the cyclooxygenase inhibitor, ibuprofen, with the TRPV1 antagonist decreased inflammatory thermal hyperalgesia in transgenic but not wild-type animals. Our results reveal a previously undescribed mechanism for keratinocyte participation in thermal pain transduction through keratinocyte TRPV3 ion channels and the intercellular messenger PGE2. PMID:19091963

  5. Efficient T-cell priming and activation requires signaling through prostaglandin E2 (EP) receptors.

    PubMed

    Sreeramkumar, Vinatha; Hons, Miroslav; Punzón, Carmen; Stein, Jens V; Sancho, David; Fresno, Manuel; Cuesta, Natalia

    2016-01-01

    Understanding the regulation of T-cell responses during inflammation and auto-immunity is fundamental for designing efficient therapeutic strategies against immune diseases. In this regard, prostaglandin E2 (PGE2) is mostly considered a myeloid-derived immunosuppressive molecule. We describe for the first time that T cells secrete PGE2 during T-cell receptor stimulation. In addition, we show that autocrine PGE2 signaling through EP receptors is essential for optimal CD4(+) T-cell activation in vitro and in vivo, and for T helper 1 (Th1) and regulatory T cell differentiation. PGE2 was found to provide additive co-stimulatory signaling through AKT activation. Intravital multiphoton microscopy showed that triggering EP receptors in T cells is also essential for the stability of T cell-dendritic cell (DC) interactions and Th-cell accumulation in draining lymph nodes (LNs) during inflammation. We further demonstrated that blocking EP receptors in T cells during the initial phase of collagen-induced arthritis in mice resulted in a reduction of clinical arthritis. This could be attributable to defective T-cell activation, accompanied by a decline in activated and interferon-γ-producing CD4(+) Th1 cells in draining LNs. In conclusion, we prove that T lymphocytes secret picomolar concentrations of PGE2, which in turn provide additive co-stimulatory signaling, enabling T cells to attain a favorable activation threshold. PGE2 signaling in T cells is also required for maintaining long and stable interactions with DCs within LNs. Blockade of EP receptors in vivo impairs T-cell activation and development of T cell-mediated inflammatory responses. This may have implications in various pathophysiological settings. PMID:26051593

  6. Activated prostaglandin D2 receptors on macrophages enhance neutrophil recruitment into the lung

    PubMed Central

    Jandl, Katharina; Stacher, Elvira; Bálint, Zoltán; Sturm, Eva Maria; Maric, Jovana; Peinhaupt, Miriam; Luschnig, Petra; Aringer, Ida; Fauland, Alexander; Konya, Viktoria; Dahlen, Sven-Erik; Wheelock, Craig E.; Kratky, Dagmar; Olschewski, Andrea; Marsche, Gunther; Schuligoi, Rufina; Heinemann, Akos

    2016-01-01

    Background Prostaglandin (PG) D2 is an early-phase mediator in inflammation, but its action and the roles of the 2 D-type prostanoid receptors (DPs) DP1 and DP2 (also called chemoattractant receptor–homologous molecule expressed on TH2 cells) in regulating macrophages have not been elucidated to date. Objective We investigated the role of PGD2 receptors on primary human macrophages, as well as primary murine lung macrophages, and their ability to influence neutrophil action in vitro and in vivo. Methods In vitro studies, including migration, Ca2+ flux, and cytokine secretion, were conducted with primary human monocyte-derived macrophages and neutrophils and freshly isolated murine alveolar and pulmonary interstitial macrophages. In vivo pulmonary inflammation was assessed in male BALB/c mice. Results Activation of DP1, DP2, or both receptors on human macrophages induced strong intracellular Ca2+ flux, cytokine release, and migration of macrophages. In a murine model of LPS-induced pulmonary inflammation, activation of each PGD2 receptor resulted in aggravated airway neutrophilia, tissue myeloperoxidase activity, cytokine contents, and decreased lung compliance. Selective depletion of alveolar macrophages abolished the PGD2-enhanced inflammatory response. Activation of PGD2 receptors on human macrophages enhanced the migratory capacity and prolonged the survival of neutrophils in vitro. In human lung tissue specimens both DP1 and DP2 receptors were located on alveolar macrophages along with hematopoietic PGD synthase, the rate-limiting enzyme of PGD2 synthesis. Conclusion For the first time, our results show that PGD2 markedly augments disease activity through its ability to enhance the proinflammatory actions of macrophages and subsequent neutrophil activation. PMID:26792210

  7. Prostaglandin E2-dependent IL-23 production in aged murine dendritic cells

    PubMed Central

    Myer, Rebecca G.; Mezayen, Rabab El; High, Kevin P.

    2010-01-01

    CD4+ T cells of the Th17 subtype are over-represented in the aged immune system. Dendritic cells (DC) play a critical role in naive CD4+ T cell differentiation. However, expression of cytokines by aged DC that promote differentiation or survival of Th17 cells has not been extensively investigated. Using bone marrow-derived DC from C57BL/6 mice of different ages we compared cytokine production after DC activation by Toll-like receptor agonists for TLR4 and/or TLR7/8. DC-derived TNF-α and IL-12p70 production and expression of DC co-stimulatory molecules did not vary significantly by age indicating TLR expression, function and signal transduction were intact in aged DC. There were relatively minor age-related changes in TGF-β and IL-6 which promote Th17 differentiation, but IL-23, a Th17-suvival cytokine, increased more than 40-fold across the lifespan. DC-derived prostaglandin E2 (PGE2) also increased with age and the up-regulation of IL-23 expression by aged DC was blocked by indomethacin that prevents PGE2 production, and by antagonists of PGE2 receptors. Exogenous PGE2 added to DC cultures further enhanced IL-23 production from aged but not young DCs. These data indicate that age-related changes in DC PGE2 production are necessary, but not sufficient to induce DC IL-23 production. Such changes may play a role in the expansion of Th17 cells in the aged immune system. PMID:20600778

  8. Acute effect of prostaglandins and somatostatin on thymidine uptake of gastric mucosa cells

    SciTech Connect

    Alino, S.F.; Hilario, E. )

    1988-12-01

    This study compares the in vivo effect of exogenous administration of prostaglandin E2 (30 {mu}g/kg) and its precursor, arachidonic acid (30 {mu}g/kg), with the effect of indomethacin (5 mg/kg) on the 6-({sup 3}H)thymidine uptake of antral mucosa of mice by autoradiographical methods. Likewise, the effect of somatostatin (30 {mu}g/kg) on 6-({sup 3}H)thymidine uptake is studied. Evaluation of the number of labeled cells, in the histological sections of the gastric mucosa, showed that arachidonic acid, prostaglandin E2, and somatostatin induced an increase in the number of labeled cells (107, 44, and 45%, respectively), while indomethacin induced a decrease of 32% compared to the control group. These results suggest that prostaglandins may mediate stimulatory effects on thymidine uptake of gastric mucosa cells in the first step after drug administration.

  9. Promising alternative clinical uses of prostaglandin F2α analogs: beyond the eyelashes.

    PubMed

    Choi, Young M; Diehl, Joseph; Levins, Paul C

    2015-04-01

    Prostaglandin F2α analogs, commonly prescribed for glaucoma treatment, have been shown to induce side effects such as cutaneous hypertrichosis and hyperpigmentation. Therefore, these medications have theoretic applications in the treatment of alopecia and disorders of hypopigmentation. We reviewed the literature to find original studies assessing the use of prostaglandin F2α analogs in these settings. Studies and reports were analyzed in regards to androgenic alopecia, alopecia areata, chemotherapy-induced alopecia, vitiligo, and hypopigmented scarring. Based on the results of these studies, and consideration of pathophysiologic mechanism, the most promising applications for prostaglandin F2α analogs include androgenic alopecia, chemotherapy-induced alopecia, and alopecia areata concurrently treated with corticosteroids. PMID:25601618

  10. Adipocyte Mineralocorticoid Receptor Activation Leads to Metabolic Syndrome and Induction of Prostaglandin D2 Synthase.

    PubMed

    Urbanet, Riccardo; Nguyen Dinh Cat, Aurelie; Feraco, Alessandra; Venteclef, Nicolas; El Mogrhabi, Soumaya; Sierra-Ramos, Catalina; Alvarez de la Rosa, Diego; Adler, Gail K; Quilliot, Didier; Rossignol, Patrick; Fallo, Francesco; Touyz, Rhian M; Jaisser, Frédéric

    2015-07-01

    Metabolic syndrome is a major risk factor for the development of diabetes mellitus and cardiovascular diseases. Pharmacological antagonism of the mineralocorticoid receptor (MR), a ligand-activated transcription factor, limits metabolic syndrome in preclinical models, but mechanistic studies are lacking to delineate the role of MR activation in adipose tissue. In this study, we report that MR expression is increased in visceral adipose tissue in a preclinical mouse model of metabolic syndrome and in obese patients. In vivo conditional upregulation of MR in mouse adipocytes led to increased weight and fat mass, insulin resistance, and metabolic syndrome features without affecting blood pressure. We identified prostaglandin D2 synthase as a novel MR target gene in adipocytes and AT56, a specific inhibitor of prostaglandin D2 synthase enzymatic activity, blunted adipogenic aldosterone effects. Moreover, translational studies showed that expression of MR and prostaglandin D2 synthase is strongly correlated in adipose tissues from obese patients. PMID:25966493

  11. Stretch-induced prostaglandins and protein turnover in cultured skeletal muscle

    NASA Technical Reports Server (NTRS)

    Vandenburgh, Herman H.; Hatfaludy, Sophia; Sohar, Istvan; Shansky, Janet

    1990-01-01

    The purpose of the study is to determine whether mechanical stimulation of cultured muscle cells influences prostaglandin efflux rates and whether they are related to stretch-induced alterations in protein turnover rates. The materials and methods of the experiment, including cell cultures, mechanical stimulation, protein synthesis, and degradation assays are outlined, and emphasis is placed on the effect of short-term mechanical stimulation in basal medium prostaglandin efflux from cultured skeletal muscle and stretch-induced alterations in prostaglandins efflux in complete medium. The major finding of the study is that mechanical stimulation of tissue-cultured skeletal-muscle cells under conditions inducing skeletal-muscle hypertropy increases the efflux of PGE(2) and PGE(2-alpha) but not 6-keto-PGF(1-alpha), the prostacyclin product.

  12. Ulcerating and stenosing enteropathy treated with misoprostol: a case report with analysis of prostaglandin metabolism.

    PubMed

    Havelund, Troels; Jensen, Boye L; Vinholt, Pernille J; Engvad, Birte; Stubbe, Jane

    2012-10-01

    A case of a 40-year-old man with chronic anaemia because of nonspecific ulcerating and stenosing enteropathy is presented. The diagnosis was made on the basis of capsule endoscopy, histology of resected ileum and no use of NSAIDs. He showed a clinical response to treatment with misoprostol, and therefore, he was investigated for a possible impairment in eicosanoid biosynthesis compared with healthy controls. No deficient synthesis of prostacyclin, prostaglandin E2 and thromboxane was found on examination of metabolites in blood and urine. This suggests a normal release of arachidonic acid from phospholipids. Ex-vivo cyclooxygenase (COX) assays showed normal COX-1 and COX-2 activities. The clinical response to treatment with the prostaglandin E1 analogue misoprostol suggests a defective prostaglandin E synthesis in the intestinal mucosa. PMID:22786573

  13. Improving placental blood flow in pre-eclampsia with prostaglandin A1.

    PubMed

    Toppozada, M; Medhat, I; Sallam, H; Ismail, A A; el-Badawy, E S; Abd Rabbo, S

    1992-01-01

    Prostaglandin A1 is a potent hypotensive, peripheral vasodilator, a weak oxytocic, antiplatelet aggregator. It improves the renal hemodynamics. Its effect on placental circulation was evaluated (expressed as systolic/diastolic ratio and umbilical artery resistance index) in 20 women with severe pre-eclampsia and 10 normotensive pregnant women, by using the Doppler technique. Moreover, another 10 women with severe pre-eclampsia received dextrose 5% as a placebo for comparative purposes. Significant improvements in both parameters studied were observed in the women with severe pre-eclampsia. The beneficial changes differed significantly from the recorded values when using dextrose in pre-eclampsia or prostaglandin A1 in normotensive subjects. Such promising data add another important perspective to prostaglandin A1 in severe pre-eclampsia and may open up new avenues for its use in other situations with compromised placental flow. PMID:1315092

  14. Inhibition of the Prostaglandin Degrading Enzyme 15-PGDH Potentiates Tissue Regeneration *

    PubMed Central

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

    2015-01-01

    Tissue regeneration is a medical challenge faced in injury from disease and during medical treatments such as bone marrow transplantation. Prostaglandin PGE2, which supports expansion of several types of tissue stem cells, is a candidate therapeutic target for promoting tissue regeneration in vivo. Here we show that inhibition of 15-hydroxyprostaglandin dehydrogenase (15-PGDH), a prostaglandin-degrading enzyme, potentiates tissue regeneration in multiple organs in mice. In a chemical screen, we identify a small-molecule inhibitor of 15-PGDH (SW033291) that increases prostaglandin PGE2 levels in bone marrow and other tissues. SW033291 accelerates hematopoietic recovery in mice receiving a bone marrow transplant. SW033291 also promotes tissue regeneration in mouse models of colon and liver injury. Tissues from 15-PGDH knockout mice demonstrate similar increased regenerative capacity. These findings raise the possibility that inhibiting 15-PGDH could be a useful therapeutic strategy in several distinct clinical settings. PMID:26068857

  15. Prostaglandin D2 modulates calcium signals induced by prostaglandin E2 in neurons of rat dorsal root ganglia.

    PubMed

    Ott, Daniela; Simm, Björn; Pollatzek, Eric; Gerstberger, Rüdiger; Rummel, Christoph; Roth, Joachim

    2015-06-15

    Fever in response to a localized subcutaneous stimulation with a low dose of lipopolysaccharide (LPS) can be attenuated by co-administration of a local anesthetic or the non-selective cyclooxygenase (COX) inhibitor diclofenac at doses, which do not exert systemic effects when injected at sites remote from the area of inflammatory stimulation. These results suggest a participation of neuronal afferent signals mediated by COX-products in the manifestation of fever under these conditions. We therefore, measured intracellular Ca(2+)-concentrations in cultured neurons from rat dorsal root ganglia (DRG) stimulated with the pyrogenic mediator prostaglandin E2 (PGE2), the anti-inflammatory and antipyretic mediator PGD2, mixtures of both PGs, and menthol using the fura-2 ratio imaging technique. Neurons could be grouped according to their size with diameters of about 15μm (small), 35μm (medium sized), or 55μm (large). 96 out of 264 neurons responded to PGE2 with pronounced Ca(2+)-signals, 53 of them being also responsive to menthol, indicative of their function as cold-sensors. 80% of these neurons belonged to the medium sized group. In a next experiment, we tested whether Ca(2+)-signals of PGE2 responsive neurons were modulated by PGD2. In 60% of all neurons investigated (n=57), the strength of the PGE2-induced Ca(2+)-signals was reduced by co-administration of PGD2. This effect was also observed in those neurons that were responsive to PGE2 and menthol (n=23; p<0.001). This observation indicates antagonistic effects of PGE2 and PGD2 on a neuronal pathway that involves cold sensors and is activated during a localized subcutaneous inflammation. This finding might provide an explanation for the reported antipyretic and anti-inflammatory capacities of PGD2. PMID:25912777

  16. A novel multifunctional metabolic pathway in a marine mollusc leads to unprecedented prostaglandin derivatives (prostaglandin 1,15-lactones).

    PubMed Central

    Di Marzo, V; Cimino, G; Crispino, A; Minardi, C; Sodano, G; Spinella, A

    1991-01-01

    The discovery of high levels of prostaglandin (PG) 1,15-lactones of both the E and F series and their co-existence with PGs has been recently described in the opisthobranch mollusc Tethys fimbria. The present study was undertaken in order to investigate the biosynthesis of these novel natural PG derivatives in vivo using radiolabelled precursors, and to gain a preliminary understanding of their biological role. PGE2 1,15-lactone was shown to be produced from both PGE2 and PGF2 alpha in the mollusc mantle and appeared to be quickly transferred to the mollusc dorsal appendices (cerata). The detachment of the latter during the typical defence behaviour of T. fimbria was accompanied by the conversion of PGE2 and PGE3 1,15-lactones back to the corresponding PGs. Both PGE2 and PGE2 1,15-lactone were also shown to be biosynthesized from arachidonic acid. Lactones of the F series were present as 11-acetyl derivatives in T. fimbria mantle and as 9- and 11-fatty acyl esters in the mollusc egg-mass and reproductive gland, and their biosynthesis from PGF2 alpha was demonstrated in all of these tissues. A multiple biological role of PG 1,15-lactones in T. fimbria defensive behaviour, smooth muscle contraction and egg production/fertilization control is hypothesized. The high amounts of PG derivatives found in T. fimbria and the biosynthetic studies described herein indicate that this marine mollusc may be a useful model for future studies on PG biosynthesis. PMID:1899996

  17. Effects of prostaglandin E2 and vascular endothelial growth factor on sperm might lead to endometriosis-associated infertility.

    PubMed

    Lee, Te-Ching; Ho, Han-Chen

    2011-01-01

    Significantly higher levels of prostaglandin E2 and vascular endothelial growth factor were associated with the severity of endometriosis. In this study, pathologic concentrations of prostaglandin E2 and vascular endothelial growth factor found in endometriotic women significantly inhibited sperm motility, acrosome reaction, and sperm-oocyte interaction, which might result in endometriosis-associated subfertility/infertility. PMID:20864099

  18. Prostaglandins A1 and E1 influence gene expression in an established insect cell line (BCIRL-HzAM1)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In work to determine the biochemical mechanisms of prostaglandin (PG) action in insect cells, we posed the hypothesis that prostaglandins (PGs) influence gene expression. In separate experiments, we exposed the BCIRL-HzAM1 cell line (derived from pupal ovarian tissue of the cotton bollworm, Helicov...

  19. Arachidonoyl ethanolamide (AEA)-induced Apoptosis is Mediated by J-series Prostaglandins and is Enhanced by Fatty Acid Amide Hydrolase (FAAH) Blockade

    PubMed Central

    Kuc, Christian; Jenkins, Audrey; Van Dross, R. T.

    2011-01-01

    The endocannabinoid arachidonoyl ethanolamide (AEA) is a potent inducer of tumor cell apoptosis however its mechanism of cytotoxicity is unclear. A previous report from our laboratory showed that AEA induced cell death in a COX-2-dependent manner and in this report our data indicate that AEA-induced apoptosis is mediated by COX-2 metabolic products of the J-series. In experiments conducted with JWF2 keratinocytes which overexpress COX-2, AEA caused a concentration-regulated increase in J-series prostaglandin production and apoptosis. Similarly, cell treatment with exogenously added J-series prostaglandins (15-deoxy, Δ12,14 PGJ2 and PGJ2) induced apoptosis. AEA-induced apoptosis was inhibited by the antioxidant, N-acetyl cysteine, indicating that reactive oxygen species generation was required for apoptosis. Using antagonists of cannabinoid receptor 1, cannabinoid receptor 2, or TRPV1, it was observed that cannabinoid receptor inhibition did not block AEA-mediated cell death. In contrast, an inhibitor of fatty acid amide hydrolase (FAAH) potentiated AEA-induced J-series PG synthesis and apoptosis. These results suggest that the metabolism of AEA to J-series PGs regulates the induction of apoptosis in cells with elevated COX-2 levels. Our data further indicate that the proapoptotic activity of AEA can be enhanced by combining it with an inhibitor of FAAH. As such, AEA may be an effective agent to eliminate tumor cells that overexpress COX-2. PMID:21432910

  20. Melittin stimulates liver glycogenolysis and the release of prostaglandin D2 and thromboxane B2.

    PubMed Central

    García-Sáinz, J A; Hernández-Sotomayor, S M; Macías-Silva, M

    1990-01-01

    Melittin stimulates glycogenolysis and induces vasoconstriction in perfused rat liver. The effect was rapid and associated with production and release of prostaglandin D2 and thromboxane B2. Indomethacin blocked the release of these eicosanoids and the stimulation of glycogenolysis induced by melittin. Ibuprofen blocked the release of prostaglandin D2 induced by melittin and markedly attenuated that of thromboxane B2. Interestingly, the initial burst of glucose output induced by melittin was not inhibited by ibuprofen, although the duration of the glycogenolytic action of the peptide was greatly diminished. PMID:2375756

  1. Fenamates may antagonize the actions of prostaglandin endoperoxides in human myometrium.

    PubMed Central

    Sanger, G J; Bennett, A

    1979-01-01

    1 The prostaglandin endoperoxide analogue U-46619 potently contracted human isolated myometrium, suggesting that prostaglandin H2 (PGH2) may be a major stimulant of myometrial contractions. 2 Sodium mefenamate, flufenamate or meclofenamate 2 microgram/ml greatly reduced contractions of the myometrium induced by the PGH2 analogue. 3 Flufenamate, but not the other two drugs, also significantly inhibited contractions to acetylcholine. 4 Sodium meclofenamate 2 microgram/ml did not consistently antagonize contractions to PGF2alpha. 5 The relief of dysmenorrhoea by fenamates may be explained both by inhibition of PG synthesis, and by antagonism of contractions to PGH2 produced by incompletely blocked PG synthesis. PMID:508555

  2. Evaluation of WO 2012/177618 A1 and US-2014/0179750 A1: novel small molecule antagonists of prostaglandin-E2 receptor EP2.

    PubMed

    Ganesh, Thota

    2015-07-01

    Recent studies underscore that prostaglandin-E2 exerts mostly proinflammatory effects in chronic CNS and peripheral disease models, mainly through a specific prostanoid receptor EP2. However, very few highly characterized EP2 receptor antagonists have been reported until recently, when Pfizer and Emory University published two distinct classes of EP2 antagonists with good potency, selectivity and pharmacokinetics. The purpose of this article is to evaluate recently published patents WO 2012/177618 A1 and US-2014/0179750 A1 from Emory, which describe a number of cinnamic amide- and amide-derivatives as a potent antagonists of EP2 receptor, and their neuroprotective effects in in vitro and in an in vivo model. A selected compound from this patent(s) also attenuates prostate cancer cell growth and invasion in vitro, suggesting these compounds should be developed for therapeutic use. PMID:25772215

  3. Prostaglandin E2 Exerts Multiple Regulatory Actions on Human Obese Adipose Tissue Remodeling, Inflammation, Adaptive Thermogenesis and Lipolysis

    PubMed Central

    García-Alonso, Verónica; Titos, Esther; Alcaraz-Quiles, Jose; Rius, Bibiana; Lopategi, Aritz; López-Vicario, Cristina; Jakobsson, Per-Johan; Delgado, Salvadora; Lozano, Juanjo; Clària, Joan

    2016-01-01

    Obesity induces white adipose tissue (WAT) dysfunction characterized by unremitting inflammation and fibrosis, impaired adaptive thermogenesis and increased lipolysis. Prostaglandins (PGs) are powerful lipid mediators that influence the homeostasis of several organs and tissues. The aim of the current study was to explore the regulatory actions of PGs in human omental WAT collected from obese patients undergoing laparoscopic bariatric surgery. In addition to adipocyte hypertrophy, obese WAT showed remarkable inflammation and total and pericellular fibrosis. In this tissue, a unique molecular signature characterized by altered expression of genes involved in inflammation, fibrosis and WAT browning was identified by microarray analysis. Targeted LC-MS/MS lipidomic analysis identified increased PGE2 levels in obese fat in the context of a remarkable COX-2 induction and in the absence of changes in the expression of terminal prostaglandin E synthases (i.e. mPGES-1, mPGES-2 and cPGES). IPA analysis established PGE2 as a common top regulator of the fibrogenic/inflammatory process present in this tissue. Exogenous addition of PGE2 significantly reduced the expression of fibrogenic genes in human WAT explants and significantly down-regulated Col1α1, Col1α2 and αSMA in differentiated 3T3 adipocytes exposed to TGF-β. In addition, PGE2 inhibited the expression of inflammatory genes (i.e. IL-6 and MCP-1) in WAT explants as well as in adipocytes challenged with LPS. PGE2 anti-inflammatory actions were confirmed by microarray analysis of human pre-adipocytes incubated with this prostanoid. Moreover, PGE2 induced expression of brown markers (UCP1 and PRDM16) in WAT and adipocytes, but not in pre-adipocytes, suggesting that PGE2 might induce the trans-differentiation of adipocytes towards beige/brite cells. Finally, PGE2 inhibited isoproterenol-induced adipocyte lipolysis. Taken together, these findings identify PGE2 as a regulator of the complex network of interactions

  4. Prostaglandin release by cultured endometrial tissues after challenge with lipopolysaccharide and tumor necrosis factor α, in relation to the estrous cycle, treatment with medroxyprogesterone acetate, and pyometra.

    PubMed

    Jursza-Piotrowska, Ewelina; Socha, Piotr; Skarzynski, Dariusz Jan; Siemieniuch, Marta Jolanta

    2016-04-01

    To better understand the pathogenesis of endometrial changes in cats associated with administration of progestagen contraceptives and with pyometra, we examined local variability of the prostaglandin synthesis system after challenge with either tumor necrosis factor α (TNF-α) or lipopolysaccharide (LPS) in organ cultures of endometrial tissues derived from cyclic cats, cats treated with medroxyprogesterone acetate (MPA), or cats with pyometra, as well as in cultured endometrial epithelial and stromal cells. In addition, spontaneous prostaglandin secretion was compared in endometria from different experimental groups. Data gathered in the present study show that the concentration of PGE2 in supernatants was increased only in endometrial organ cultures from cats with pyometra (P < 0.001) compared with other groups. This was also true for PGF2α in pyometra, compared with cats treated either short- or long-term with MPA and cats during late diestrus (P < 0.001), anestrus (P < 0.01), and estrus and middiestrus (P < 0.05). Treatment with LPS and TNF-α combined stimulated PGE2 secretion in all groups compared with the control (P < 0.001 for endometria of cats during anestrus or middiestrus, cats treated short-term with MPA, and those with pyometra; P < 0.01 for endometria of cats treated long-term with MPA; and P < 0.05 for the endometria of cats during estrus and late diestrus). The combined treatment with LPS and TNF-α increased PGF2α secretion in the endometria of cats treated short-term with MPA (P < 0.001), during anestrus and pyometra (P < 0.01 for both), and estrus and middiestrus (P < 0.05 for both), compared with the control. Spontaneous secretion of prostaglandins was several times greater in the endometria of queens with pyometra, compared with other groups, which may further regulate the local inflammatory response. Data gathered from endometrial cell culture and endometrial organ culture lead to the conclusion that disturbances in prostaglandin release

  5. Prostaglandins modify phosphorylation of specific proteins in the insect cell line BCIRL-HzAM1

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Prostaglandins (PGs) play crucial roles in vertebrate biology, particularly in immune functions. Because PGs also mediate specific cell functions in insect immunity, we are investigating how these signaling molecules affect insect cells. We reported that PGs, notably PGA1, PGA2, and PGE1, up and/or ...

  6. The Influence of Topical Prostaglandin Analogues in Inflammation After Selective Laser Trabeculoplasty Treatment

    PubMed Central

    Chen, Enping

    2012-01-01

    Abstract Purpose Reducing intraocular pressure (IOP) seems to be the only treatment that slows progression in glaucoma. The IOP can be decreased by pharmaceutical treatment, laser [selective laser trabeculoplasty (SLT)] treatment, or surgery. Prostaglandin analogues have been postulated to share action mechanisms with SLT and to possibly diminish the effects of SLT treatment. The aim of the current study was to investigate the effects of prostaglandin analogues in inflammation and IOP reduction after SLT treatment. Methods Prospective nonrandomized study. One hundred and eighteen patients were included in the study. Inclusion criteria: Glaucoma (open-angle or pseudoexfoliation glaucoma) patients who will be treated with SLT. Inflammation was measured with a laser flare meter (Kowa FM-500). Measurements were made before SLT and then 2 h, 1 week, and 1 month after SLT treatment. IOP was also checked at the same time intervals. The SLT treatment was performed over 90°. All patients were divided into two groups: those receiving prostaglandins analogues and those treated with nonprostaglandin analogues. Results Inflammation before and after SLT showed no significant difference between the groups at all the time intervals studied (t-test, before: P=0.16; 2 h: P=0.14; 1 week: P=0.12; and 1 month: P=0.36). IOP reduction showed no significant difference between the groups (t-test, P=0.31). Conclusions SLT treatment effects do not seem to be influenced by the use of prostaglandin analogues. PMID:22087857

  7. Effect of Diethylcarbamazine (DEC) on prostaglandin levels in Wuchereria bancrofti infected microfilaraemics.

    PubMed

    Sankari, T; Hoti, S L; Das, L K; Govindaraj, V; Das, P K

    2013-06-01

    Diethylcarbamazine (DEC) interferes with arachidonic acid metabolism for the clearance of microfilariae in Wuchereria bancrofti infected individuals. In this study, we have quantified the plasma concentrations of prostaglandin E2 (PGE2) and 6-keto-PGF1α, the end products of arachidonic acid metabolic pathway in microfilaraemics (DEC treated and untreated), and normal healthy individuals at pre- and 3,9,12,36, and 72 h of post-DEC treatment. We have also determined the microfilariae counts at pre and post day 2 (36 h) and day 3 (72 h) of DEC treatment by membrane filtration technique. Significant reduction in PGE2 and 6-keto-PGF1α concentrations was found at 12 h of DEC treatment. Rapid reduction in microfilarial counts was observed at 36 h of post-DEC treatment. Higher levels of prostaglandins were found at pre-treatment hours in microfilaraemics compared to normal healthy individuals (P < 0.05). Our findings indicate that DEC inhibits prostaglandins for the clearance of microfilariae, and increased levels of prostaglandins in microfilaraemics may be contributed by the parasite or host upon stimulation. PMID:23525692

  8. Insect anti-viral immunity: roles of prostaglandins and other eicosanoids

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Insect/microbe relationships are very complex, with an array of signaling systems acting in surveillance, detection and responses to the presence of microbes. We report that prostaglandins (PGs) are responsible for essential signaling in activating and coordinating insect innate immune reactions to ...

  9. Prostaglandin potentiates 5-HT responses in stomach and ileum innervating visceral afferent sensory neurons.

    PubMed

    Kim, Sojin; Jin, Zhenhua; Lee, Goeun; Park, Yong Seek; Park, Cheung-Seog; Jin, Young-Ho

    2015-01-01

    Gastrointestinal disorder is a common symptom induced by diverse pathophysiological conditions that include food tolerance, chemotherapy, and irradiation for therapy. Prostaglandin E2 (PGE2) level increase was often reported during gastrointestinal disorder and prostaglandin synthetase inhibitors has been used for ameliorate the symptoms. Exogenous administration of PGE2 induces gastrointestinal disorder, however, the mechanism of action is not known. Therefore, we tested PGE2 effect on visceral afferent sensory neurons of the rat. Interestingly, PGE2 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 PGE2-induced potentiation were blocked by a selective E-prostanoid type 4 (EP4) receptors antagonist, L-161,982, but type 1 and 2 receptor antagonist AH6809 has no effect. A membrane permeable protein kinase A (PKA) inhibitor, KT5720 also inhibited PGE2 effects. PGE2 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 PGE2 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 synthetase inhibitors by selectively targeting EP4 receptor/PKA pathway without interrupt prostaglandin synthesis. PMID:25446121

  10. Long-chain acyl-CoA synthetase 4 modulates prostaglandin E2 release from human arterial smooth muscle cells

    PubMed Central

    Golej, Deidre L.; Askari, Bardia; Kramer, Farah; Barnhart, Shelley; Vivekanandan-Giri, Anuradha; Pennathur, Subramaniam; Bornfeldt, Karin E.

    2011-01-01

    Long-chain acyl-CoA synthetases (ACSLs) catalyze the thioesterification of long-chain FAs into their acyl-CoA derivatives. Purified ACSL4 is an arachidonic acid (20:4)-preferring ACSL isoform, and ACSL4 is therefore a probable regulator of lipid mediator production in intact cells. Eicosanoids play important roles in vascular homeostasis and disease, yet the role of ACSL4 in vascular cells is largely unknown. In the present study, the ACSL4 splice variant expressed in human arterial smooth muscle cells (SMCs) was identified as variant 1. To investigate the function of ACSL4 in SMCs, ACSL4 variant 1 was overexpressed, knocked-down by small interfering RNA, or its enzymatic activity acutely inhibited in these cells. Overexpression of ACSL4 resulted in a markedly increased synthesis of arachidonoyl-CoA, increased 20:4 incorporation into phosphatidylethanolamine, phosphatidylinositol, and triacylglycerol, and reduced cellular levels of unesterified 20:4. Accordingly, secretion of prostaglandin E2 (PGE2) was blunted in ACSL4-overexpressing SMCs compared with controls. Conversely, acute pharmacological inhibition of ACSL4 activity resulted in increased release of PGE2. However, long-term downregulation of ACSL4 resulted in markedly reduced PGE2 secretion. Thus, ACSL4 modulates PGE2 release from human SMCs. ACSL4 may regulate a number of processes dependent on the release of arachidonic acid-derived lipid mediators in the arterial wall. PMID:21242590

  11. Two-year treatment patterns and costs in glaucoma patients initiating treatment with prostaglandin analogs

    PubMed Central

    Schmier, Jordana K; Lau, Edmund C; Covert, David W

    2010-01-01

    Objective To determine treatment patterns and costs over a two-year period among new initiators of topical prostaglandin analogs in a managed care population by retrospective cohort analysis of an insurance claims database. Methods Patients who initiated therapy with a prostaglandin analog between September 2006 and March 2007 were identified. The use of monotherapy and adjunctive therapies were compared by index prostaglandin. Days to initiation of adjunctive therapy and rates of glaucoma surgical procedures were also calculated. Medical costs (antiglaucoma medications and ophthalmic visits) over the two-year period were estimated. Results The analysis identified 5018 patients with at least one prostaglandin analog prescription (bimatoprost, n = 747; latanoprost, n = 1651; benzalkonium chloride (BAK)-free travoprost, n = 203). The majority (51%–54%) had repeat prescriptions. Among those with repeat prescriptions, 52% were female (not significant) and mean age was 64 years (P < 0.01). Rates of adjunctive therapy use varied across groups (bimatoprost 51%, latanoprost 37%, and BAK- free travoprost 35%, P < 0.0001). Median and mean days to initiation of adjunctive therapy were 83 and 140 for bimatoprost, 101 and 181 for latanoprost, and 113 and 221 for BAK- free travoprost. Two-year medical costs were $3147, $2843, and $2557 for patients initiating treatment with bimatoprost, latanoprost, and BAK-free travoprost, respectively. Use of glaucoma surgical procedures across the treatment groups was similar over the two-year period. Conclusions Over a two-year period, the rate and time to initiation of adjunctive therapy use, as well as medical costs, varied between index prostaglandins. However, the rate of glaucoma surgical interventions did not vary significantly across index medications. PMID:20957061

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

    PubMed Central

    Chi, Yuling; Jasmin, Jean-Francois; Seki, Yoshinori; Lisanti, Michael P.; Charron, Maureen J.; Lefer, David J.; Schuster, Victor L.

    2015-01-01

    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. PMID:26121580

  13. The Role of Prostaglandins and COX-Enzymes in Chondrogenic Differentiation of ATDC5 Progenitor Cells

    PubMed Central

    Caron, Marjolein M. J.; Emans, Pieter J.; Sanen, Kathleen; Surtel, Don A. M.; Cremers, Andy; Ophelders, Daan; van Rhijn, Lodewijk W.; Welting, Tim J. M.

    2016-01-01

    Objectives NSAIDs are used to relieve pain and decrease inflammation by inhibition of cyclooxygenase (COX)-catalyzed prostaglandin (PG) synthesis. PGs are fatty acid mediators involved in cartilage homeostasis, however the action of their synthesizing COX-enzymes in cartilage differentiation is not well understood. In this study we hypothesized that COX-1 and COX-2 have differential roles in chondrogenic differentiation. Methods ATDC5 cells were differentiated in the presence of COX-1 (SC-560, Mofezolac) or COX-2 (NS398, Celecoxib) specific inhibitors. Specificity of the NSAIDs and inhibition of specific prostaglandin levels were determined by EIA. Prostaglandins were added during the differentiation process. Chondrogenic outcome was determined by gene- and protein expression analyses. Results Inhibition of COX-1 prevented Col2a1 and Col10a1 expression. Inhibition of COX-2 resulted in decreased Col10a1 expression, while Col2a1 remained unaffected. To explain this difference expression patterns of both COX-enzymes as well as specific prostaglandin concentrations were determined. Both COX-enzymes are upregulated during late chondrogenic differentiation, whereas only COX-2 is briefly expressed also early in differentiation. PGD2 and PGE2 followed the COX-2 expression pattern, whereas PGF2α and TXA2 levels remained low. Furthermore, COX inhibition resulted in decreased levels of all tested PGs, except for PGD2 and PGF2α in the COX-1 inhibited condition. Addition of PGE2 and PGF2α resulted in increased expression of chondrogenic markers, whereas TXA2 increased expression of hypertrophic markers. Conclusions Our findings point towards a differential role for COX-enzymes and PG-production in chondrogenic differentiation of ATDC5 cells. Ongoing research is focusing on further elucidating the functional partition of cyclooxygenases and specific prostaglandin production. PMID:27050768

  14. Modulation of mammary cancer cell migration by 15-deoxy-Δ12,14-prostaglandin J2: implications for anti-metastatic therapy

    PubMed Central

    Diers, Anne R.; Dranka, Brian P.; Ricart, Karina C.; Oh, Joo Yeun; Johnson, Michelle S.; Zhou, Fen; Pallero, Manuel A.; Bodenstine, Thomas M.; Murphy-Ullrich, Joanne E.; Welch, Danny R.; Aimee, Landar

    2010-01-01

    SYNOPSIS Recently, a number of steps in the progression of metastatic disease have been shown to be regulated by redox signaling. Electrophilic lipids affect redox signaling through the post-translational modification of critical cysteine residues in proteins. However, the therapeutic potential as well as the precise mechanisms of action of electrophilic lipids in cancer cells is poorly understood. In this study, we investigate the effect of the electrophilic prostaglandin 15-deoxy-Δ12,14-prostaglandin J2 (15d-PGJ2) on metastatic properties of breast cancer cells. 15d-PGJ2 was shown to decrease migration, stimulate focal adhesion disassembly and cause extensive F-actin reorganization at low concentrations (0.03-0.3 μM). Importantly, these effects seem to be independent of PPARγ and modification of actin or Keap1, which are known protein targets of 15d-PGJ2 at higher concentrations. Interestingly, the p38 inhibitor SB203580 was able to prevent both 15d-PGJ2-induced F-actin reorganization and focal adhesion disassembly. Taken together, our results suggest that electrophiles such as 15d-PGJ2 are potential anti-metastatic agents which exhibit specificity for migration and adhesion pathways at low concentrations where there are no observed effects on Keap1 or cytotoxicity. PMID:20536428

  15. 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.

    PubMed

    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. PMID:27185495

  16. Prostaglandin Transporter (PGT/SLCO2A1) Protects the Lung from Bleomycin-Induced Fibrosis

    PubMed Central

    Nakanishi, Takeo; Wakayama, Tomohiko; Uetoko, Yuka; Komori, Hisakazu; Akanuma, Shin-ichi; Hosoya, Ken-ichi; Tamai, Ikumi

    2015-01-01

    Prostaglandin (PG) E2 exhibits an anti-fibrotic effect in the lung in response to inflammatory reactions and is a high-affinity substrate of PG transporter (SLCO2A1). The present study aimed to evaluate the pathophysiological relevance of SLCO2A1 to bleomycin (BLM)-induced pulmonary fibrosis in mice. Immunohistochemical analysis indicated that Slco2a1 protein was expressed in airway and alveolar type I (ATI) and II (ATII) epithelial cells, and electron-microscopic immunohistochemistry further demonstrated cell surface expression of Slco2a1 in ATI cells in wild type (WT) C57BL/6 mice. PGE2 uptake activity was abrogated in ATI-like cells from Slco2a1-deficient (Slco2a1-/-) mice, which was clearly observed in the cells from WT mice. Furthermore, the PGE2 concentrations in lung tissues were lower in Slco2a1-/- than in WT mice. The pathological relevance of SLCO2A1 was further studied in mouse BLM-induced pulmonary fibrosis models. BLM (1 mg/kg) or vehicle (phosphate buffered saline) was intratracheally injected into WT and Slco2a1-/- mice, and BLM-induced fibrosis was evaluated on day 14. BLM induced more severe fibrosis in Slco2a1-/- than in WT mice, as indicated by thickened interstitial connective tissue and enhanced collagen deposition. PGE2 levels were higher in bronchoalveolar lavage fluid, but lower in lung tissues of Slco2a1-/- mice. Transcriptional upregulation of TGF-β1 was associated with enhanced gene transcriptions of downstream targets including plasminogen activator inhitor-1. Furthermore, Western blot analysis demonstrated a significant activation of protein kinase C (PKC) δ along with a modest activation of Smad3 in lung from Slco2a1-/- mice, suggesting a role of PKCδ associated with TGF-β signaling in aggravated fibrosis in BLM-treated Slco2a1-/- mice. In conclusion, pulmonary PGE2 disposition is largely regulated by SLCO2A1, demonstrating that SLCO2A1 plays a critical role in protecting the lung from BLM-induced fibrosis. PMID:25923111

  17. The number of tartrate-resistant acid phosphatase-positive osteoclasts on neonatal mouse parietal bones is decreased when prostaglandin synthesis is inhibited and increased in response to prostaglandin E2, parathyroid hormone, and 1,25 dihydroxyvitamin D3.

    PubMed

    Marshall, M J; Holt, I; Davie, M W

    1995-03-01

    The culture of parietal bones from 4-day old mice in indomethacin (Ind) for 1 day caused a large reduction in the number of tartrate-resistant acid phosphatase positive osteoclasts (TRAP + OC) relative to both control bones and to freshly isolated bones. This reduction did not occur if prostaglandin E2 (PGE2) was present. When 5-bromo-2'-deoxyuridine (BDU) was injected into 4-day old mice, newly formed TRAP + OC nuclei became labeled 1 day later; these bones were then cultured with Ind for 1 day. TRAP + OC and newly labeled TRAP+OC nuclei were commensurately decreased in number. This suggests an active down-regulation rather than merely the inhibition of new TRAP+OC formation. Incubation of bones with Ind and either PGE2, parathyroid hormone, or 1,25 dihydroxyvitamin D3 for 6 hours following a 1-day preincubation in Ind, resulted in an increase in TRAP + OC compared with Ind alone. Using BDU labeling in vitro and in vivo, we show that this increase in number of TRAP+OC is not the result of cell proliferation, but rather differentiation of postmitotic precursors. PMID:7538445

  18. Involvement of prostaglandin I(2) in nitric oxide-induced vasodilation of retinal arterioles in rats.

    PubMed

    Mori, Asami; Namekawa, Ryo; Hasebe, Masami; Saito, Maki; Sakamoto, Kenji; Nakahara, Tsutomu; Ishii, Kunio

    2015-10-01

    The soluble guanylyl cyclase/cGMP system plays an important role in the vasodilator response to nitric oxide (NO) in various vascular beds. However, in rat retinal arterioles, the cyclooxygenase-1/cAMP-mediated pathway contributes to the vasodilator effects of NO, although the specific prostanoid involved remains to be elucidated. In the present study, we investigated the role of prostaglandin I2 and its receptor (prostanoid IP receptor) system in NO-induced vasodilation of rat retinal arterioles in vivo. Fundus images were captured using a digital camera that was equipped with a special objective lens. Changes in diameter of retinal arterioles were assessed. The NO donor (±)-(E)-4-ethyl-2-[(E)-hydroxyimino]-5-nitro-3-hexenamide (NOR3) increased the diameter of retinal arterioles but decreased systemic blood pressure in a dose-dependent manner. Treatment of rats with indomethacin, a non-selective cyclooxygenase inhibitor, markedly attenuated the retinal vasodilator, but not depressor responses to NOR3. The prostanoid IP receptor antagonist 4,5-dihydro-N-[4-[[4-(1-methylethoxy)phenyl]methyl]phenyl]-1H-imadazol-2-amine (CAY10441), and the prostaglandin I2 synthase inhibitor 9α,11α-azoprosta-5Z,13E-dien-1-oic acid (U-51605), both showed similar preventive effects against the NOR3-induced retinal vasodilator response. Neither CAY10441 nor U-51605 showed any significant effects on the depressor response to NOR3. NOR3 enhanced the release of prostaglandin I2 from cultured human retinal microvascular endothelial cells and the NOR3-induced prostaglandin I2 release was almost completely abolished by the cyclooxygenase-1 inhibitor SC-560, but not by the cyclooxygenase-2 inhibitor NS-398. However, NOR3 did not increase the release of prostaglandin I2 from human intestinal microvascular endothelial cells. These results suggest that NO exerts its dilatory effect via cyclooxygenase-1/prostaglandin I2/prostanoid IP receptor signaling mechanisms in the retinal vasculature. PMID

  19. Importance of adipocyte cyclooxygenase-2 and prostaglandin E2-prostaglandin E receptor 3 signaling in the development of obesity-induced adipose tissue inflammation and insulin resistance.

    PubMed

    Chan, Pei-Chi; Hsiao, Fone-Ching; Chang, Hao-Ming; Wabitsch, Martin; Hsieh, Po Shiuan

    2016-06-01

    We examined the involvement of adipocyte cyclooxygenase-2 (COX-2) and prostaglandin E2 (PGE2)-prostaglandin E receptor (EP)3-mediated signaling during hypertrophy and hypoxia in the development of obesity-associated adipose tissue (AT) inflammation and insulin resistance. The experiments were conducted with high-fat diet (HFD)-induced obese rats, db/db mice, human subjects, and 3T3-L1 and the human Simpson-Golabi-Behmel syndrome (SGBS) adipocytes; the groups were treated with selective inhibitors of COX-2 [celecoxib 30 mg/kg, half maximal inhibitory concentration (IC50) ≈ 0.04 µM] and EP3 (L-798106 100 µg/kg, IC50 ≈ 0.5 µM) or a short interfering RNA. There were strong, positive correlations between adipocyte COX-2 and EP3 gene expressions and the AT TNF-α and monocyte chemotactic protein-1 contents and the homeostatic model assessment for insulin resistance in HFD-induced obese rats, as well as body mass index in human subjects. Treatment with COX-2 and EP3 inhibitors significantly reversed AT inflammatory gene and protein expressions (-50%) and impaired glucose and insulin tolerance in db/db mice. COX-2 inhibition diminished the chemotaxis of adipocytes isolated from HFD rats to macrophages and T cells. Targeting inhibition of adipocyte COX-2 and EP3 during hypertrophy and hypoxia reversed the release of the augmented proinflammatory adipokines and the diminished adiponectin and also suppressed NF-κB and hypoxia-inducible factor-1α transcription activation. These findings suggest that adipocyte COX-2 PGE2-EP3-mediated signaling is crucially involved in the development of obesity-associated AT inflammation and insulin resistance.-Chan, P.-C., Hsiao, F.-C., Chang, H.-M., Wabitsch, M., Hsieh, P. S. Importance of adipocyte cyclooxygenase-2 and prostaglandin E2-prostaglandin E receptor 3 signaling in the development of obesity-induced adipose tissue inflammation and insulin resistance. PMID:26932930

  20. Inhibition of microsomal prostaglandin E synthase-1 by aminothiazoles decreases prostaglandin E2 synthesis in vitro and ameliorates experimental periodontitis in vivo

    PubMed Central

    Kats, Anna; Båge, Tove; Georgsson, Pierre; Jönsson, Jörgen; Quezada, Hernán Concha; Gustafsson, Anders; Jansson, Leif; Lindberg, Claes; Näsström, Karin; Yucel-Lindberg, Tülay

    2013-01-01

    The potent inflammatory mediator prostaglandin E2 (PGE2) is implicated in the pathogenesis of several chronic inflammatory conditions, including periodontitis. The inducible enzyme microsomal prostaglandin E synthase-1 (mPGES-1), catalyzing the terminal step of PGE2 biosynthesis, is an attractive target for selective PGE2 inhibition. To identify mPGES-1 inhibitors, we investigated the effect of aminothiazoles on inflammation-induced PGE2 synthesis in vitro, using human gingival fibroblasts stimulated with the cytokine IL-1β and a cell-free mPGES-1 activity assay, as well as on inflammation-induced bone resorption in vivo, using ligature-induced experimental periodontitis in Sprague-Dawley rats. Aminothiazoles 4-([4-(2-naphthyl)-1,3-thiazol-2-yl]amino)phenol (TH-848) and 4-(3-fluoro-4-methoxyphenyl)-N-(4-phenoxyphenyl)-1,3-thiazol-2-amine (TH-644) reduced IL-1β-induced PGE2 production in fibroblasts (IC50 1.1 and 1.5 μM, respectively) as well as recombinant mPGES-1 activity, without affecting activity or expression of the upstream enzyme cyclooxygenase-2. In ligature-induced experimental periodontitis, alveolar bone loss, assessed by X-ray imaging, was reduced by 46% by local treatment with TH-848, compared to vehicle, without any systemic effects on PGE2, 6-keto PGF1α, LTB4 or cytokine levels. In summary, these results demonstrate that the aminothiazoles represent novel mPGES-1 inhibitors for inhibition of PGE2 production and reduction of bone resorption in experimental periodontitis, and may be used as potential anti-inflammatory drugs for treatment of chronic inflammatory diseases, including periodontitis.—Kats, A., Båge, T., Georgsson, P., Jönsson, J., Quezada, H. C., Gustafsson, A., Jansson, L., Lindberg, C., Näsström, K., Yucel-Lindberg, T. Inhibition of microsomal prostaglandin E synthase-1 by aminothiazoles decreases prostaglandin E2 synthesis in vitro and ameliorates experimental periodontitis in vivo. PMID:23447581

  1. Prostaglandin D2 signaling mediated by the CRTH2 receptor is involved in MK-801-induced cognitive dysfunction.

    PubMed

    Onaka, Yusuke; Shintani, Norihito; Nakazawa, Takanobu; Kanoh, Takuya; Ago, Yukio; Matsuda, Toshio; Hashimoto, Ryota; Ohi, Kazutaka; Hirai, Hiroyuki; Nagata, Kin-Ya; Nakamura, Masataka; Kasai, Atsushi; Hayata-Takano, Atsuko; Nagayasu, Kazuki; Takuma, Kazuhiro; Ogawa, Asao; Baba, Akemichi; Hashimoto, Hitoshi

    2016-11-01

    Chemoattractant receptor-homologous molecule expressed on T helper type 2 cells (CRTH2), which is a second receptor for prostaglandin (PG) D2, is involved in inflammatory responses in peripheral tissue; however, its role in cognitive function remains unclear. Here, we demonstrate that CRTH2 is involved in cognitive function using a well-established animal model of cognitive dysfunction induced by MK-801, an N-methyl-d-aspartate receptor antagonist. Genetic deletion and pharmacological inhibition of CRTH2 suppressed MK-801-induced cognitive dysfunction. Pharmacological inhibition of cyclooxygenase-1, a rate-limiting enzyme in PG synthesis, also suppressed MK-801-induced cognitive dysfunction. Moreover, an MK-801-induced increase in c-Fos expression in the paraventricular nucleus (PVN) was abolished in the CRTH2-deficient mice. Together, these results suggest that PGD2-CRTH2 signaling is involved in both MK-801-induced cognitive dysfunction and neuronal activity regulation in the PVN. Furthermore, genetic association studies suggest that CRTH2 is weakly associated with cognitive function in humans. Our study provides evidence that PGD2-CRTH2 signaling is involved in cognitive function and may represent a potential therapeutic target for cognitive dysfunction in patients with psychiatric disorders. PMID:27481693

  2. Prostaglandin F2α promotes muscle cell survival and growth through upregulation of the inhibitor of apoptosis protein BRUCE

    PubMed Central

    Jansen, Katie M.; Pavlath, Grace K.

    2009-01-01

    During skeletal muscle growth and regeneration, the majority of differentiating myoblasts undergoes cell-cell fusion to form multinucleated myofibers, while a proportion of myoblasts undergoes apoptosis. The treatment of myoblasts with prostaglandin F2α (PGF2α) during myogenesis in vitro leads to the formation of large myotubes, but the mechanism by which PGF2α promotes myotube growth has not been investigated. Here, we demonstrate that PGF2α reduces cell death during myogenesis in vitro and in vivo. In addition, we show that PGF2α increases expression of the inhibitor of apoptosis protein (IAP) BRUCE through a pathway dependent upon the nuclear factor of activated T cell 2 (NFATC2) transcription factor. Importantly, PGF2α-mediated reduction in muscle cell death is dependent upon BRUCE, and overexpression of BRUCE is sufficient to promote muscle cell survival and growth. These results establish a previously unrecognized link between NFAT signaling and regulation of IAP expression and are the first to identify a signaling pathway that increases BRUCE expression. In addition, our results provide evidence that increasing the pool of muscle cells available for fusion by inhibiting cell death enhances myotube growth. PMID:18566603

  3. Prostaglandin D(2) induces apoptosis of human osteoclasts through ERK1/2 and Akt signaling pathways.

    PubMed

    Yue, Li; Haroun, Sonia; Parent, Jean-Luc; de Brum-Fernandes, Artur J

    2014-03-01

    In a recent study we have shown that prostaglandin D2 (PGD2) induces human osteoclast (OC) apoptosis through the activation of the chemoattractant receptor homologous molecule expressed on T-helper type 2 cell (CRTH2) receptor and the intrinsic apoptotic pathway. However, the molecular mechanisms underlying this response remain elusive. The objective of this study is to investigate the intracellular signaling pathways mediating PGD2-induced OC apoptosis. OCs were generated by in vitro differentiation of human peripheral blood mononuclear cells (PBMCs), and then treated with or without the selective inhibitors of mitogen-activated protein kinase-extracellular signal-regulated kinase (ERK) kinase, (MEK)-1/2, phosphatidylinositol3-kinase (PI3K) and NF-κB/IκB kinase-2 (IKK2) prior to the treatments of PGD2 as well as its agonists and antagonists. Fluorogenic substrate assay and immunoblotting were performed to determine the caspase-3 activity and key proteins involved in Akt, ERK1/2 and NF-κB signaling pathways. Treatments with both PGD2 and a CRTH2 agonist decreased ERK1/2 (Thr202/Tyr204) and Akt (Ser473) phosphorylation, whereas both treatments increased β-arrestin-1 phosphorylation (Ser412) in the presence of naproxen, which was used to eliminate endogenous prostaglandin production. In the absence of naproxen, treatment with a CRTH2 antagonist increased both ERK1/2 and Akt phosphorylations, and reduced the phosphorylation of β-arrestin-1. Treatment of OCs with a selective MEK-1/2 inhibitor increased caspase-3 activity and OC apoptosis induced by both PGD2 and a CRTH2 agonist. Moreover, a CRTH2 antagonist diminished the selective MEK-1/2 inhibitor-induced increase in caspase-3 activity in the presence of endogenous prostaglandins. In addition, treatment of OCs with a selective PI3K inhibitor decreased ERK1/2 (Thr202/Tyr204) phosphorylation caused by PGD2, whereas increased ERK1/2 (Thr202/Tyr204) phosphorylation by a CRTH2 antagonist was attenuated with a PI3K

  4. Abnormal Expression of Prostaglandins E2 and F2α Receptors and Transporters in Patients with Endometriosis

    PubMed Central

    Rakhila, Halima; Bourcier, Nathalie; Akoum, Ali; Pouliot, Marc

    2015-01-01

    Objective. To investigate the level of expression of prostaglandin receptivity and uptake factors in eutopic and ectopic endometrium of women with endometriosis. Design. Prospective study. Setting. Human reproduction research laboratory. Patients. Seventy-eight patients with endometriosis and thirty healthy control subjects. Intervention(s). Endometrial and endometriotic tissue samples were obtained during laparoscopic surgery. Main Outcome Measure(s). Real-time polymerase chain reaction assay of mRNA encoding prostaglandin E2 receptors (EP1, EP2, EP3, and EP4), prostaglandin F2α receptor (FP), prostaglandin transporter (PGT), and multidrug resistance-associated protein 4 (MRP4); immunohistochemical localization of expressed proteins. Results. Marked increases in receptors EP3, EP4, and FP and transporters PGT and MRP4 in ectopic endometrial tissue were noted, without noticeable change associated with disease stage. An increase in EP3 expression and decreases in FP and PGT were observed in the eutopic endometrium of endometriosis patients in conjunction with the phases of the menstrual cycle. Conclusion(s). This study is the first to demonstrate a possible relationship between endometriosis and enhanced prostaglandin activity. In view of the wide range of prostaglandin functions, increasing cell receptivity and facilitating uptake in endometrial tissue could contribute to the initial steps of overgrowth and have an important role to play in the pathogenesis and symptoms of this disease. PMID:26240828

  5. In vitro prostaglandin E2 stimulation of /sup 45/Ca mobilization from chick bone

    SciTech Connect

    Satterlee, D.G.; Amborski, G.F.; McIntyre, M.D.; Parker, M.S.; Jacobs-Perry, L.A.

    1984-04-01

    The ability of prostaglandin E2 (PGE2) to mobilize /sup 45/Ca from chick embryo long bones was assayed in an in vitro bone culture system. Concentrations of PGE2 tested ranged from 10(-9) to 10(-5) M. The PGE2 was effective in stimulating release of /sup 45/Ca from prelabelled bones at all concentrations tested except at 10(-9) M. In addition, stimulation of /sup 45/Ca release could be produced daily for 4 consecutive days of PGE2 culture-pulsing at what appeared to be the optimal PGE2 concentration, 10(-7) M. The authors conclude, as in mammals, PGE2 is a potent stimulator of calcium mobilization from avian bone. The potential involvement of prostaglandins in eggshell formation is discussed.

  6. A prospective self-controlled study of fertility after second-trimester prostaglandin-induced abortion.

    PubMed

    MacKenzie, I Z; Fry, A

    1988-05-01

    One hundred forty women whose pregnancies were terminated in the second trimester with prostaglandins because of suspected fetal disease have been prospectively followed to assess their subsequent fertility. In six instances difficulties had been experienced in conceiving the pregnancy that was terminated. Since abortion 104 women have conceived, 97% within 24 months of abortion but in five instances after some delay. Only one woman had not succeeded in conceiving a wished-for pregnancy. There were no apparent differences in abortion management between those women readily conceiving and those in whom there was some delay, although termination because of chromosomal reasons or anatomic abnormalities was less commonly followed by another pregnancy as compared with those terminated for rubella or other viral infections. Reduced fertility after a late prostaglandin-induced abortion thus appears to be very infrequent. PMID:3369497

  7. Inhibition of microsomal prostaglandin E synthase-1 as targeted therapy in cancer treatment.

    PubMed

    Larsson, Karin; Jakobsson, Per-Johan

    2015-07-01

    The bioactive lipid prostaglandin E2 (PGE2) is involved in several steps of carcinogenesis in some of the most common cancers, e.g. colon cancer, lung cancer, prostate cancer and breast cancer. Non-steroidal anti-inflammatory drugs (NSAIDs) that target cyclooxygenase (COX) activity, the first step of the PGE2 biosynthesis, has been found to reduce the incidence of colon cancer. Due to severe adverse effects on the gastrointestinal tract and the cardiovascular system, their use as chemopreventing agent has been hampered. Genetic deletion of microsomal prostaglandin E synthase-1 (mPGES-1), the enzyme responsible for the second step of the PGE2 biosynthesis, has resulted in reduced tumor progression in mouse models of colon cancer. Inhibition of mPGES-1 would potentially be beneficial to a great number of patients without the side effects associated with long-term treatment with traditional NSAIDs. PMID:26100239

  8. Preoperative cervical dilatation by vaginal pessaries containing prostaglandin E1 analogue.

    PubMed

    Chen, J K; Elder, M G

    1983-09-01

    A double-blind trial comparing use of placebo with use of a single intravaginal pessary of 1 mg 16,16-dimethyl-trans-delta 2-prostaglandin E1 methyl ester, inserted approximately three hours before first-trimester surgical abortion, was carried out. There were 54 women each in the study and control groups. A spring gauge was used to record the force required to dilate the cervix. With the use of the prostaglandin analogue, operative time, blood loss, and the need for additional mechanical dilatation of the cervix were significantly reduced compared with the control group (P less than .0001). This reduction greatly facilitates the operation and should reduce the incidence of cervical trauma. PMID:6348613

  9. Does Prostaglandin D2 hold the cure to male pattern baldness?

    PubMed Central

    Nieves, Ashley; Garza, Luis A.

    2014-01-01

    Lipids in the skin are the most diverse in the entire human body. Their bioactivity in health and disease is underexplored. Prostaglandin D2 has recently been identified as a factor which is elevated in the bald scalp of men with androgenetic alopecia and has the capacity to decrease hair lengthening. An enzyme which synthesizes it, prostaglandin D2 synthase (PTGDS or lipocalin-PGDS) is hormone responsive in multiple other organs. PGD2 has two known receptors, GPR44 and PTGDR. GPR44 was found to be necessary for the decrease in hair growth by PGD2. This creates an exciting opportunity to perhaps create novel treatments for androgenetic alopecia which inhibit the activity of PTGDS, PGD2 or GPR44. This review discusses the current knowledge surrounding PGD2 and future steps needed to translate these findings into novel therapies for patients with androgenetic alopecia. PMID:24521203

  10. Prostaglandin-Associated Periorbital Lipodystrophy in Cosmetic Eyelid Surgery: A Novel Cause of Facial Asymmetry.

    PubMed

    Eftekhari, Kian; Mifflin, Mark D; Anderson, Richard L

    2016-03-01

    A 70-year-old woman presented to our practice with profound ptosis of the left upper eyelid and notable asymmetry of the periocular area. On examination, she was noted to have significant atrophy of the periocular tissues on the left side, with lower eyelid retraction. These features were present but less severe on the right side. Upon further questioning, she stated that she had cataract surgery on the left side that was complicated by a high intraocular pressure and required subsequent secondary surgery. She had taken a prostaglandin eyedrop for many months after her cataract surgery to keep the eye pressure low. Recently, a newly recognized adverse effect of prostaglandin eyedrops has been described in the ophthalmic literature in which patients develop periorbital lipodystrophy. This case emphasizes that this may occur unilaterally in patients taking the eyedrop in only one eye, and should be recognized prior to considering functional and aesthetic surgery of the periocular area. PMID:26374814

  11. Antagonist of prostaglandin E2 receptor 4 induces metabolic alterations in liver of mice.

    PubMed

    Li, Ning; Zhang, Limin; An, Yanpeng; Zhang, Lulu; Song, Yipeng; Wang, Yulan; Tang, Huiru

    2015-03-01

    Prostaglandin E2 receptor 4 (EP4) is one of the receptors for prostaglandin E2 and plays important roles in various biological functions. EP4 antagonists have been used as anti-inflammatory drugs. To investigate the effects of an EP4 antagonist (L-161982) on the endogenous metabolism in a holistic manner, we employed a mouse model, and obtained metabolic and transcriptomic profiles of multiple biological matrixes, including serum, liver, and urine of mice with and without EP4 antagonist (L-161982) exposure. We found that this EP4 antagonist caused significant changes in fatty acid metabolism, choline metabolism, and nucleotide metabolism. EP4 antagonist exposure also induced oxidative stress to mice. Our research is the first of its kind to report information on the alteration of metabolism associated with an EP4 antagonist. This information could further our understanding of current and new biological functions of EP4. PMID:25669961

  12. Prostaglandin synthesis in aorta of atherosclerosis susceptible and atherosclerosis resistant pigeons.

    PubMed

    Subbiah, M T; Schweiger, E; Deitmeyer, D; Gallon, L; Sinzinger, H

    1980-01-01

    The aortas of 9 months aged Show Racer and White Carneau pigeons were examined for their PGE2, PGF2 alpha and 6-keto-PGF1 alpha synthesis from labelled arachidonic acid by radiothinlayer chromatography. The prostacyclin formation was estimated by means of Moncada's bioassay. PGE2 and PGF 2 alpha synthesis in the aorta of pigeons is higher than in rats, whereas less 6-keto-PGF1 alpha is formed in pigeon aortas. The susceptible White Carneau pigeons synthesitize more prostaglandins than the resistant Show Racer pigeons. PGI2 and 6-keto-PGF 1 alpha-formation is extremely low in avian arota. These data are in part contradicting to our findings im mammalians (where the atherosclerosis susceptible animals generate less PGI2) and warrants sequential measurements of prostaglandin synthesis in aorta to assess its significance during various stages of atherogenesis. PMID:7425865

  13. [Current conservative treatment of renal colic: value of prostaglandin synthesis inhibitors].

    PubMed

    Zwergel, U; Felgner, J; Rombach, H; Zwergel, T

    1998-04-20

    Prostaglandin synthesis inhibitors and parasympatholytic drugs are often used as analgetics in the case of renal colic. This paper analyzes how and whether these drug effects are important for the analgetic therapy. In an animal and in a human model with acutely obstructed kidneys we found that intravenous application of Indometacine and dipyrone significantly reduces renal pelvic pressure. The parasympatholytic drug hyoscine butylbromide did not produce any change of upper urinary tract dynamics. Inhibitors of prostaglandin synthesis thus effect pressure reduction in the renal pelvis, which is necessary for analgetic therapy. In contrast, hyoscine butylbromide does not have any influence on the acute upper urinary tract obstruction; consequently its usefulness in the treatment of renal colic is rather doubtful. PMID:12799978

  14. I - Prostaglandin hyperalgesia, a cAMP/Ca2+ dependent process.

    PubMed

    Ferreira, S H; Nakamura, M

    1979-08-01

    Prostaglandins stimulate cAMP increase in several biological systems including CNS. The possible participation of a cAMP/Ca2+ related mechanism in prostaglandin induced hyperalgesia in the rat paw, as measured by a modification of the Randall-Selitto method was investigated. A serie of agents was administered in the paw in an attempt to change either Ca2+ or cyclic AMP concentration at the nociceptive terminations. PGE2, dibutyryl cyclic AMP, isoprenaline, noradrenaline, adrenaline, Ca2+ionophore (A23187), BaCl2 caused a dose dependent hyperalgesia. The hyperalgesic effect of these substances was enhanced by methyl-xanthines. Cyclic GMP as well as agents which interfere with Ca2+ influx (verapamil and lanthanum) were local analgesics in normal and hyperalgesic paws. PMID:230542

  15. Antagonism by antipyretics of the hyperthermic effect of a prostaglandin precursor, sodium arachidonate, in the cat.

    PubMed Central

    Clark, W G; Cumby, H R

    1976-01-01

    1. Injection of sodium arachidonate (100-400 mug) into lateral cerebral ventricles of unanaesthetized cats caused shivering and rapid development of dose-related hyperthermic responses. Unless arachidonate is hyperthermogenic per se, this indicates that in vivo formation of prostaglandins, or perhaps an endoperoxide intermediate, can cause hyperthermia. 2. Tolerance gradually developed when arachidonate was administered repeatedly at intervals of 1-7 days. Examination of the brains of several tolerant animals revealed in each case marked enlargement of the lateral ventricles which apparently accounted for the diminished response to arachidonate. 3. Sodium salicylate (40, 160 mg/kg, i.v.) antagonized arachidonate but only after a 3-4 hr latent period. 4. Paracetamol (10, 40 mg/kg, i.v.) reduced the hyperthermic effect of arachidonate but a dose of 40 mg/kg antagonized centrally administered bacterial endotoxin more effectively than it did arachidonate. 5. Indomethacin (40 mug/kg, i.v.) significantly reduced arachidonate-induced hyperthermia in only one of two studies. This reduction was comparable to the hypothermic effect of indomethacin in afebrile animals and was attributed to a non-specific action on thermoregulatory function rather than to inhibition of prostaglandin synthesis. Indomethacin antagonized endotoxin and leucocytic pyrogen to a greater degree than it did arachidonate. 6. Comparison of the relative effectiveness of the antipyretics in blocking hyperthermic responses to pyrogens and to sodium arachidonate indicates that, if prostaglandins do mediate pyrogen-induced fever, these antipyretics exert their primary at a step before prostaglandin synthesis. PMID:950606

  16. Requirement of cyclooxygenase-2 expression and prostaglandins for human prostate cancer cell invasion.

    PubMed

    Nithipatikom, Kasem; Isbell, Marilyn A; Lindholm, Paul F; Kajdacsy-Balla, Andre; Kaul, Sushma; Campell, William B

    2002-01-01

    The PC-3 Low Invasive cells and the PC-3 High Invasive cells were used to investigate the correlation of the COX-2 expression and its arachidonic acid metabolites, prostaglandins, with their invasiveness through Matrigel using a Boyden chamber assay. The COX-2 expression in PC-3 High Invasive cells was approximately 3-fold higher than in PC-3 Low Invasive cells while the COX-1 expression was similar in both cell sublines. When incubated with arachidonic acid, PGE2 was the major prostaglandin produced by these cells. PC-3 High Invasive cells produced PGE2 approximately 2.5-fold higher than PC-3 Low Invasive cells. PGD2 was the second most abundant prostaglandin produced by these cells. Both indomethacin (a nonspecific COX inhibitor) and NS-398 (a specific COX-2 inhibitor) inhibited the production of prostaglandins and the cell invasion. PGE2 alone did not induce the cell invasion of PC-3 Low Invasive cells. However, PGE2 reversed the inhibition of cell invasion by NS-398 and enhanced the cell invasion of the PC-3 High Invasive cells. In contrast, PGD2 slightly inhibited the cell invasion. These results suggest that in the PC-3 Low Invasive cells, COX-2-derived PGE2 may not be sufficient to induce cell invasion while in the PC-3 High Invasive cells, PGE2 may be sufficient to act as an enhancer for the cell invasion. Further, PGD2 may represent a weak inhibitor and counteracts the effect of PGE2 in the cell invasion. PMID:12498388

  17. Comparison of nociceptive behavior in prostaglandin E, F, D, prostacyclin and thromboxane receptor knockout mice.

    PubMed

    Popp, Laura; Häussler, Annett; Olliges, Anke; Nüsing, Rolf; Narumiya, Shuh; Geisslinger, Gerd; Tegeder, Irmgard

    2009-08-01

    Antagonist at specific prostaglandin receptors might provide analgesia with a more favourable toxicity profile compared with cyclooxygenase inhibitors. We analyzed nociceptive responses in prostaglandin D, E, F, prostacyclin and thromboxane receptor knockout mice and mice deficient of cyclooxygenase 1 or 2 to evaluate the contribution of individual prostaglandin receptors for heat, mechanical and formalin-evoked pain. None of the knockouts was uniformly protected from all of these pain stimuli but COX-1 and EP4 receptor knockouts presented with reduced heat pain and EP3 receptor and COX-2 knockout mice had reduced licking responses in the 2nd phase of the formalin assay. This was accompanied with reduced c-Fos immunoreactivity in the spinal cord dorsal horn in EP3 knockouts. Oppositely, heat pain sensitivity was increased in FP, EP1 and EP1+3 double mutant mice possibly due to a loss of FP or EP1 receptor mediated central control of thermal pain sensitivity. Deficiency of either EP2 or DP1 was associated with increased formalin-evoked flinching responses and c-Fos IR in dorsal horn neurons suggesting facilitated spinal cord pain reflex circuity. Thromboxane and prostacyclin receptor knockout mice showed normal pain behavior in all tests. The results suggest a differential, pain-stimulus and site-specific contribution of specific PG-receptors for the processing of the nociceptive stimuli, a differential modulation of nociceptive responses by COX-1 and COX-2 derived prostaglandins and compensatory and/or developmental adaptations in mice lacking specific PG receptors. PMID:18938093

  18. Biochemical Warfare on the Reef: The Role of Glutathione Transferases in Consumer Tolerance of Dietary Prostaglandins

    PubMed Central

    Whalen, Kristen E.; Lane, Amy L.; Kubanek, Julia; Hahn, Mark E.

    2010-01-01

    Background Despite the profound variation among marine consumers in tolerance for allelochemically-rich foods, few studies have examined the biochemical adaptations underlying diet choice. Here we examine the role of glutathione S-transferases (GSTs) in the detoxification of dietary allelochemicals in the digestive gland of the predatory gastropod Cyphoma gibbosum, a generalist consumer of gorgonian corals. Controlled laboratory feeding experiments were used to investigate the influence of gorgonian diet on Cyphoma GST activity and isoform expression. Gorgonian extracts and semi-purified fractions were also screened to identify inhibitors and possible substrates of Cyphoma GSTs. In addition, we investigated the inhibitory properties of prostaglandins (PGs) structurally similar to antipredatory PGs found in high concentrations in the Caribbean gorgonian Plexaura homomalla. Principal Findings Cyphoma GST subunit composition was invariant and activity was constitutively high regardless of gorgonian diet. Bioassay-guided fractionation of gorgonian extracts revealed that moderately hydrophobic fractions from all eight gorgonian species examined contained putative GST substrates/inhibitors. LC-MS and NMR spectral analysis of the most inhibitory fraction from P. homomalla subsequently identified prostaglandin A2 (PGA2) as the dominant component. A similar screening of commercially available prostaglandins in series A, E, and F revealed that those prostaglandins most abundant in gorgonian tissues (e.g., PGA2) were also the most potent inhibitors. In vivo estimates of PGA2 concentration in digestive gland tissues calculated from snail grazing rates revealed that Cyphoma GSTs would be saturated with respect to PGA2 and operating at or near physiological capacity. Significance The high, constitutive activity of Cyphoma GSTs is likely necessitated by the ubiquitous presence of GST substrates and/or inhibitors in this consumer's gorgonian diet. This generalist's GSTs may

  19. Intraocular pressure dynamics with prostaglandin analogs: a clinical application of the water-drinking test

    PubMed Central

    Özyol, Pelin; Özyol, Erhan; Baldemir, Ercan

    2016-01-01

    Aim To evaluate the clinical applicability of the water-drinking test in treatment-naive primary open-angle glaucoma patients. Methods Twenty newly diagnosed primary open-angle glaucoma patients and 20 healthy controls were enrolled in this prospective study. The water-drinking test was performed at baseline and 6 weeks and 3 months after prostaglandin analog treatment. Peak and fluctuation of intraocular pressure (IOP) measurements obtained with the water-drinking test during follow-up were analyzed. Analysis of variance for repeated measures and paired and unpaired t-tests were used for statistical analysis. Results The mean baseline IOP values in patients with primary open-angle glaucoma were 25.1±4.6 mmHg before prostaglandin analog treatment, 19.8±3.7 mmHg at week 6, and 17.9±2.2 mmHg at month 3 after treatment. The difference in mean baseline IOP of the water-drinking tests was statistically significant (P<0.001). At 6 weeks of prostaglandin analog treatment, two patients had high peak and fluctuation of IOP measurements despite a reduction in baseline IOP. After modifying treatment, patients had lower peak and fluctuation of IOP values at month 3 of the study. Conclusion Peak and fluctuation of IOP in response to the water-drinking test were lower with prostaglandin analogs compared with before medication. The water-drinking test can represent an additional benefit in the management of glaucoma patients, especially by detecting higher peak and fluctuation of IOP values despite a reduced mean IOP. Therefore, it could be helpful as a supplementary method in monitoring IOP in the clinical practice. PMID:27555742

  20. Improvement in the quality of hematopoietic prostaglandin D synthase crystals in a microgravity environment.

    PubMed

    Tanaka, Hiroaki; Tsurumura, Toshiharu; Aritake, Kosuke; Furubayashi, Naoki; Takahashi, Sachiko; Yamanaka, Mari; Hirota, Erika; Sano, Satoshi; Sato, Masaru; Kobayashi, Tomoyuki; Tanaka, Tetsuo; Inaka, Koji; Urade, Yoshihiro

    2011-01-01

    Human hematopoietic prostaglandin synthase, one of the better therapeutic target enzymes for allergy and inflammation, was crystallized with 22 inhibitors and in three inhibitor-free conditions in microgravity. Most of the space-grown crystals showed better X-ray diffraction patterns than the terrestrially grown ones, indicating the advantage of a microgravity environment on protein crystallization, especially in the case of this protein. PMID:21169700

  1. Mechanical stimulation of skeletal muscle mitigates glucocorticoid induced decreases in prostaglandin synthesis

    NASA Technical Reports Server (NTRS)

    Chromiak, Joseph A.; Vandenburgh, Herman H.

    1993-01-01

    The glucocorticoid dexamethasone (Dex) induces a decline in protein synthesis and protein content of tissue cultured, avian skeletal muscle cells, and this atrophy is attenuated by repetitive mechanical stretch. Since the prostaglandin synthesis inhibitor indomethacin mitigated this stretch attenuation of muscle atrophy, the role of prostaglandins as growth modulators in these processes was examined. Dex at 10(exp -8) M reduced PGF(sub 2(alpha)) production 55 percent - 65 percent and PGE(sub 2) production 84 - 90 percent after 24 - 72 h of incubation in static cultures. Repetitive 10 percent stretch-relaxations of the non-Dex treated cultures increased PGF(sub 2(alpha)) efflux 41 percent at 24 h and 276 percent at 72 h and increased PGE(sub 2) production 51 percent at 24 h and 236 percent at 72 h. Mechanical stimulation of Dex treated cultures increased PGF(sub 2(alpha)) production 162 percent after 24 h, thus returning PGF(sub 2(alpha)) efflux to the level of non-Dex treated cultures. At 72 h, stretch increased PGF(sub 2(alpha)) efflux 65 percent in Dex treated cultures, but PGF(sub 2(alpha)) production was 45-84 percent less than non-Dex treated cultures. Mechanical stimulation of Dex treated cultures increased PGE(sub 2) production at 24 h, but not at 72 h. Dex reduced prostaglandin H synthase (PGHS) activity in the muscle cultures by 70 percent after 8 - 24 h of incubation, and mechanical stimulation increased PGHS activity of the Dex treated cultures by 98 percent. It is concluded that repetitive mechanical stimulation attenuates the catabolic effects of Dex on cultured skeletal muscle cells in part by reversing the Dex-induced declines in PGHS activity and prostaglandin production.

  2. Positive correlation between patency and mRNA levels for cyclooxygenase-2 and prostaglandin E synthase in the uterine cervix of bitches with pyometra.

    PubMed

    Tamada, Hiromichi; Adachi, Nahoko; Kawate, Noritoshi; Inaba, Toshio; Hatoya, Shingo; Sawada, Tsutomu

    2016-03-01

    Factors involved in patency of uterine cervices in the bitch with pyometra remain to be clarified. This study examined relationship between patency and mRNA levels for inducible nitric oxide synthase (iNOS), cyclooxygenase (COX)-1, COX-2 and prostaglandin E synthase (PGES) in the uterine cervix of bitches with pyometra. Cervical patency was measured by inserting the stainless steel rods with different diameter into cervical canals. Levels of mRNA expression were determined by semi-quantitative reverse transcription-polymerase chain reaction. The cervical patency was positively correlated with mRNA levels for COX-2 and PGES, but not those for iNOS and COX-1. The results suggest that gene expression of COX-2 and PGES may be involved in the regulation of patency in the uterine cervix of bitches with pyometra. PMID:26596635

  3. Positive correlation between patency and mRNA levels for cyclooxygenase-2 and prostaglandin E synthase in the uterine cervix of bitches with pyometra

    PubMed Central

    TAMADA, Hiromichi; ADACHI, Nahoko; KAWATE, Noritoshi; INABA, Toshio; HATOYA, Shingo; SAWADA, Tsutomu

    2015-01-01

    Factors involved in patency of uterine cervices in the bitch with pyometra remain to be clarified. This study examined relationship between patency and mRNA levels for inducible nitric oxide synthase (iNOS), cyclooxygenase (COX)-1, COX-2 and prostaglandin E synthase (PGES) in the uterine cervix of bitches with pyometra. Cervical patency was measured by inserting the stainless steel rods with different diameter into cervical canals. Levels of mRNA expression were determined by semi-quantitative reverse transcription-polymerase chain reaction. The cervical patency was positively correlated with mRNA levels for COX-2 and PGES, but not those for iNOS and COX-1. The results suggest that gene expression of COX-2 and PGES may be involved in the regulation of patency in the uterine cervix of bitches with pyometra. PMID:26596635

  4. Mechanical stimulation of skeletal muscle generates lipid-related second messengers by phospholipase activation

    NASA Technical Reports Server (NTRS)

    Vandenburgh, Herman H.; Shansky, Janet; Karlisch, Patricia; Solerssi, Rosa Lopez

    1991-01-01

    Repetitive mechanical stimulation of cultured avian skeletal muscle increases the synthesis of prostaglandins E2 and F2(alpha) which regulate protein turnover rates and muscle cell growth. Mechnical stimulation significantly increases the breakdown rate of (3)H-arachidonic acid labelled phospholipids, releasing free (3)H-arachidonic acid, and the rate-limiting precursor of prostaglandin synthesis. Mechanical stimulation also significantly increases (3)H-arachidonic acid labelled diacylglycerol formation and intracellular levels of inositol phosphates from myo-2-(3)H inositol labelled phospholipids. Phospholipase A2, phosphatidylinositol-specific phospholipase C (PLC), and phospholipase D (PLD) are activated by stretch. The lipase inhibitors bromophenacylbromide and RHC80267 together reduce stretch-induced prostaglandin production by 73-83 percent. The stretch-induced increases in prostaglandin production, (3)H-arachidonic acid labelled phospholipid breakdown, and (3)H-arachidonic acid labelled diacylglycerol formation occur independently of cellular electrical activity (tetrodotoxin insensitive) whereas the formation of inositol phosphates from myo-2-(3)H inositol labelled phospholipids are dependent on cellular electrical activity. These results indicate that mechanical stimulation increases the lipid-related second messengers arachidonic acid, diacylglycerol, and prostaglandins through activation of specific phospholipases such as PLA2 and PLD, but not by activation of phosphatidylinositol-specific PLC.

  5. Gastroprotective Effect of Geopropolis from Melipona scutellaris Is Dependent on Production of Nitric Oxide and Prostaglandin.

    PubMed

    Ribeiro-Junior, Jerônimo Aparecido; Franchin, Marcelo; Cavallini, Miriam Elias; Denny, Carina; de Alencar, Severino Matias; Ikegaki, Masaharu; Rosalen, Pedro Luiz

    2015-01-01

    The aim of this study was to evaluate the gastroprotective activity of ethanolic extract of geopropolis (EEGP) from Melipona scutellaris and to investigate the possible mechanisms of action. The gastroprotective activity of the EEGP was evaluated using model ulcer induced by ethanol. To elucidate the possible mechanisms of action, we investigated the involvement of the nonprotein sulfhydryl (NP-SH) groups, nitric oxide and prostaglandins. In addition, the antisecretory activity of EEGP was also evaluated by pylorus ligated model. The EEGP orally administrated (300 mg/kg) reduced the ulcerative lesions induced by the ethanol (P < 0.05). Regarding the mechanism of action, the prior administration of nitric oxide and prostaglandins antagonists suppressed the activity of gastroprotective EEGP (P < 0.05). On the other hand the gastroprotective activity of EEGP was kept in the group pretreated with the antagonist of the NP-SH groups; furthermore the antisecretory activity was not significant (P > 0.05). These results support the alternative medicine use of geopropolis as gastroprotective and the activities observed show to be related to nitric oxide and prostaglandins production. PMID:25949263

  6. Gastroprotective Effect of Geopropolis from Melipona scutellaris Is Dependent on Production of Nitric Oxide and Prostaglandin

    PubMed Central

    Ribeiro-Junior, Jerônimo Aparecido; Franchin, Marcelo; Cavallini, Miriam Elias; Denny, Carina; de Alencar, Severino Matias; Ikegaki, Masaharu; Rosalen, Pedro Luiz

    2015-01-01

    The aim of this study was to evaluate the gastroprotective activity of ethanolic extract of geopropolis (EEGP) from Melipona scutellaris and to investigate the possible mechanisms of action. The gastroprotective activity of the EEGP was evaluated using model ulcer induced by ethanol. To elucidate the possible mechanisms of action, we investigated the involvement of the nonprotein sulfhydryl (NP-SH) groups, nitric oxide and prostaglandins. In addition, the antisecretory activity of EEGP was also evaluated by pylorus ligated model. The EEGP orally administrated (300 mg/kg) reduced the ulcerative lesions induced by the ethanol (P < 0.05). Regarding the mechanism of action, the prior administration of nitric oxide and prostaglandins antagonists suppressed the activity of gastroprotective EEGP (P < 0.05). On the other hand the gastroprotective activity of EEGP was kept in the group pretreated with the antagonist of the NP-SH groups; furthermore the antisecretory activity was not significant (P > 0.05). These results support the alternative medicine use of geopropolis as gastroprotective and the activities observed show to be related to nitric oxide and prostaglandins production. PMID:25949263

  7. Effect of radioprotectant WR 2721 on cyclic nucleotides, prostaglandins, and lysosomes

    SciTech Connect

    Trocha, P.J.; Catravas, G.N.

    1983-05-01

    Within 1 hr after ip injection of the radioprotectant WR 2721 into rats, splenic cGMP levels dropped and remained suppressed for 6 hr before returning to normal. However, if rats were exposed to ionizing radiation 30-40 min after WR 2721 treatment, they had higher cGMP levels at 3 hr postirradiation than the nonirradiUted, drug-treated controls, but the cGMP content was still found to be lower than that of the irradiated nondrug-treated controls. Radiation exposure of animals pretreated with WR 2721 also resulted in higher liver and spleen levels of cAMP and additional elevations in spleen prostaglandin content, compared with irradiated controls at 3-6 hr after radiation treatment. The secondary fluctuations of lysosomal enzyme activities, prostaglandin content, and cyclic nucleotide levels were also altered in irradiated rats pretreated with WR 2721 when compared with irradiated controls. Liver and spleen lysosomal ..beta..-glucuronidase activities, spleen cAMP and cGMP levels, and spleen prostaglandin concentrations were closer to physiological levels at 3 days postirradiation in rats given WR 2721 before the radiation treatment.

  8. [Inhibition of prostaglandins synthesis in the inflamed site results in opioid-mediated hypoalgesia in rats].

    PubMed

    Huang, Jian; Wu, Jian; Yang, Huai-Zu; Hong, Yanguo

    2016-06-25

    This study was designed to investigate the contribution of prostaglandins to the maintenance of inflammatory pain. Inflammation was induced by intraplantar (i.pl.) injection of carrageenan in right hindpaw in rats. Indomethacin (non-selective COX inhibitor) was administered i.pl. 1 h after the carrageenan injection, and paw withdrawal latency (PWL) responding to noxious heat was measured. β-endorphin (β-END) and μ-opioid receptor (MOR) expressed in the inflamed site were examined by using immunocytochemistry, ELISA and RT-PCR techniques. The results showed that indomethacin dose-dependently increased PWL to the levels that were above the baseline on the day 2 and 3, referred to as hypoalgesia. The hypoalgesia was abolished by a local injection of the non-selective opioid receptor inhibitor naloxone methiodide. The number of β-END-positive cells, the content of β-END and the expression of MOR mRNA in the inflammatory site of inflammation model rats were all significantly increased by indomethacin. These results reveal a novel mechanism of prostaglandins for the inhibition of inflammation-induced endogenous opioid activity. This study provides further evidence that inhibition of prostaglandins in inflamed site could be a promising therapy for inflammatory pain. PMID:27350196

  9. Inhibition of prostaglandin E2 receptor EP3 mitigates thrombin-induced brain injury.

    PubMed

    Han, Xiaoning; Lan, Xi; Li, Qiang; Gao, Yufeng; Zhu, Wei; Cheng, Tian; Maruyama, Takayuki; Wang, Jian

    2016-06-01

    Prostaglandin E2 EP3 receptor is the only prostaglandin E2 receptor that couples to multiple G-proteins, but its role in thrombin-induced brain injury is unclear. In the present study, we exposed mouse hippocampal slice cultures to thrombin in vitro and injected mice with intrastriatal thrombin in vivo to investigate the role of EP3 receptor in thrombin-induced brain injury and explore its underlying cellular and molecular mechanisms. In vitro, EP3 receptor inhibition reduced thrombin-induced hippocampal CA1 cell death. In vivo, EP3 receptor was expressed in astrocytes and microglia in the perilesional region. EP3 receptor inhibition reduced lesion volume, neurologic deficit, cell death, matrix metalloproteinase-9 activity, neutrophil infiltration, and the number of CD68(+) microglia, but increased the number of Ym-1(+) M2 microglia. RhoA-Rho kinase levels were increased after thrombin injection and were decreased by EP3 receptor inhibition. In mice that received an intrastriatal injection of autologous arterial blood, inhibition of thrombin activity with hirudin decreased RhoA expression compared with that in vehicle-treated mice. However, EP3 receptor activation reversed this effect of hirudin. These findings show that prostaglandin E2 EP3 receptor contributes to thrombin-induced brain damage via Rho-Rho kinase-mediated cytotoxicity and proinflammatory responses. PMID:26661165

  10. Low-dose prostaglandin E2 analogue for cervical dilatation prior to pregnancy termination.

    PubMed

    Borten, M; DiLeo, L A; Friedman, E A

    1984-11-01

    The trauma of mechanical cervical dilatation preceding abortion is directly related to the degree of cervical resistance. Prostaglandins may reduce cervical rigidity but are accompanied by undesirable side effects. Our aims were to ascertain if a low-dose (10 mg) analogue (9-deoxo-16, 16 dimethyl-9-methylene PGE2) is effective and well tolerated and, if so, to try to determine the possible mechanism by which it works. To this end, we studied 39 women with gestational ages ranging from 7 to 19 weeks who were given a single vaginal suppository 1 to 4 hours before suction curettage. In addition to demographic data on age, gravidity, parity, and previous abortions, we determined progesterone, human chorionic gonadotropin and prostaglandin plasma levels. This low-dose prostaglandin E2 analogue was found to be effective in achieving cervical dilatation and softening with minimal side effects (mild nausea in one patient only). Mean cervical dilatation achieved was 7.8 +/- 2.3 mm. Softening was apparent and facilitated additional instrumental dilatation when required. No correlation was found between drug effectiveness and gravidity, gestational age, or duration of action. There was no detectable trend with regard to baseline progesterone or human chorionic gonadotropin levels. This suggested a specific sensitivity to the local effect by the drug, apparently unrelated to dosage. PMID:6496588

  11. Identification and Characterization of Novel Microsomal Prostaglandin E Synthase-1 Inhibitors for Analgesia.

    PubMed

    Chandrasekhar, Srinivasan; Harvey, Anita K; Yu, Xiao-Peng; Chambers, Mark G; Oskins, Jennifer L; Lin, Chaohua; Seng, Thomas W; Thibodeaux, Stefan J; Norman, Bryan H; Hughes, Norman E; Schiffler, Matthew A; Fisher, Matthew J

    2016-03-01

    Prostaglandin (PG) E2 plays a critical role in eliciting inflammation. Nonsteroidal anti-inflammatory drugs and selective inhibitors of cyclooxygenase, which block PGE2 production, have been used as key agents in treating inflammation and pain associated with arthritis and other conditions. However, these agents have significant side effects such as gastrointestinal bleeding and myocardial infarction, since they also block the production of prostanoids that are critical for other normal physiologic functions. Microsomal prostaglandin E2 synthase-1 is a membrane-bound terminal enzyme in the prostanoid pathway, which acts downstream of cyclooxygenase 2 and is responsible for PGE2 production during inflammation. Thus, inhibition of this enzyme would be expected to block PGE2 production without inhibiting other prostanoids and would provide analgesic efficacy without the side effects. In this report, we describe novel microsomal prostaglandin E2 synthase-1 inhibitors that are potent in blocking PGE2 production and are efficacious in a guinea pig monoiodoacetate model of arthralgia. These molecules may be useful in treating the signs and symptoms associated with arthritis. PMID:26740668

  12. Muscle sympathetic nerve responses to physiological changes in prostaglandin production in humans

    NASA Technical Reports Server (NTRS)

    Doerzbacher, K. J.; Ray, C. A.

    2001-01-01

    Previous studies suggest that prostaglandins may contribute to exercise-induced increases in muscle sympathetic nerve activity (MSNA). To test this hypothesis, MSNA was measured at rest and during exercise before and after oral administration of ketoprofen, a cyclooxygenase inhibitor, or placebo. Twenty-one subjects completed two bouts of graded dynamic and isometric handgrip to fatigue. Each exercise bout was followed by 2 min of postexercise muscle ischemia. The second exercise bouts were performed after 60 min of rest in which 11 subjects were given ketoprofen (300 mg) and 10 subjects received a placebo. Ketoprofen significantly lowered plasma thromboxane B(2) in the drug group (from 36 +/- 6 to 22 +/- 3 pg/ml, P < 0.04), whereas thromboxane B(2) in the placebo group increased from 40 +/- 5 to 61 +/- 9 pg/ml from trial 1 to trial 2 (P < 0.008). Ketoprofen and placebo did not change sympathetic and cardiovascular responses to dynamic handgrip, isometric handgrip, and postexercise muscle ischemia. There was no relationship between thromboxane B(2) concentrations and MSNA or arterial pressure responses during both exercise modes. The data indicate that physiological increases or decreases in prostaglandins do not alter exercise-induced increases in MSNA and arterial pressure in humans. These findings suggest that contraction-induced metabolites other than prostaglandins mediate MSNA responses to exercise in humans.

  13. Role of prostaglandin D2/CRTH2 pathway on asthma exacerbation induced by Aspergillus fumigatus

    PubMed Central

    Liu, Haixia; Zheng, Mingrui; Qiao, Jianou; Dang, Yajie; Zhang, Pengyu; Jin, Xianqiao

    2014-01-01

    Aspergillus fumigatus is often associated in asthmatic patients with the exacerbation of asthma symptoms. The pathomechanism of this phenomenon has not been fully understood. Here, we evaluated the immunological mechanisms and the role of the prostaglandin D2/ Chemoattractant Receptor-Homologous Molecule Expressed on Th2 Cells (CRTH2) pathway in the development of Aspergillus-associated asthma exacerbation. We studied the effects of A. fumigatus on airway inflammation and bronchial hyper-responsiveness in a rat model of chronic asthma. Inhalation delivery of A. fumigatus conidia increased the airway eosinophilia and bronchial hyper-responsiveness in ovalbumin-sensitized, challenged rats. These changes were associated with prostaglandin D2 synthesis and CRTH2 expression in the lungs. Direct inflammation occurred in ovalbumin-sensitized, challenged animals, whereas pre-treatment with an antagonist against CRTH2 nearly completely eliminated the A. fumigatus-induced worsening of airway eosinophilia and bronchial hyper-responsiveness. Our data demonstrate that production of prostaglandin D2 followed by eosinophil recruitment into the airways via a CRTH2 receptor are the major pathogenic factors responsible for the A. fumigatus-induced enhancement of airway inflammation and responsiveness. PMID:24329550

  14. Role of prostaglandin D2 /CRTH2 pathway on asthma exacerbation induced by Aspergillus fumigatus.

    PubMed

    Liu, Haixia; Zheng, Mingrui; Qiao, Jianou; Dang, Yajie; Zhang, Pengyu; Jin, Xianqiao

    2014-05-01

    Aspergillus fumigatus is often associated in asthmatic patients with the exacerbation of asthma symptoms. The pathomechanism of this phenomenon has not been fully understood. Here, we evaluated the immunological mechanisms and the role of the prostaglandin D2 / Chemoattractant Receptor-Homologous Molecule Expressed on Th2 Cells (CRTH2) pathway in the development of Aspergillus-associated asthma exacerbation. We studied the effects of A. fumigatus on airway inflammation and bronchial hyper-responsiveness in a rat model of chronic asthma. Inhalation delivery of A. fumigatus conidia increased the airway eosinophilia and bronchial hyper-responsiveness in ovalbumin-sensitized, challenged rats. These changes were associated with prostaglandin D2 synthesis and CRTH2 expression in the lungs. Direct inflammation occurred in ovalbumin-sensitized, challenged animals, whereas pre-treatment with an antagonist against CRTH2 nearly completely eliminated the A. fumigatus-induced worsening of airway eosinophilia and bronchial hyper-responsiveness. Our data demonstrate that production of prostaglandin D2 followed by eosinophil recruitment into the airways via a CRTH2 receptor are the major pathogenic factors responsible for the A. fumigatus-induced enhancement of airway inflammation and responsiveness. PMID:24329550

  15. Blockade of prostaglandin production increases cachectin synthesis and prevents depression of macrophage functions after hemorrhagic shock.

    PubMed Central

    Ertel, W; Morrison, M H; Ayala, A; Perrin, M M; Chaudry, I H

    1991-01-01

    Although hemorrhage severely depresses macrophage functions, it is not known whether the increased TNF-alpha or PGE2 production is responsible for it. To study this C3H/HeN mice were bled to mean blood pressure of 35 mmHg for 60 minutes, resuscitated, and treated with either ibuprofen (1.0 mg/kg body weight) or vehicle (saline). Hemorrhage increased plasma prostaglandin E2 (PGE2) levels by 151.7% +/- 40.0% (p less than 0.05) and significantly decreased peritoneal macrophage (pM phi) antigen presentation (AP) by 60.5% +/- 7.3%, Ia expression by 52.3% +/- 7.6%, and interleukin-1 (IL-1) synthesis by 60.5% +/- 12.3% compared to shams. However ibuprofen treatment reduced PGE2 plasma levels by 61.3% +/- 12.1% and significantly increased AP (+237.0% +/- 95.3%), Ia expression (+72.8% +/- 27.5%), IL-1 synthesis (+235.7% +/- 134.7%), and cachectin synthesis (+485.8% +/- 209.0%) compared to vehicle-treated animals. These results indicate that prostaglandins but not cachectin are involved in the suppression of pM phi functions following hemorrhage because blockade of prostaglandin synthesis improved depressed macrophage functions despite enhanced cachectin synthesis. PMID:1998408

  16. [Intra-arterial administration of prostaglandin E1 in occlusive arterial diseases].

    PubMed

    Davidović, L; Vranes, M; Cernak, I; Kostić, D; Lovrić, A; Sagić, D; Lotina, S

    1992-01-01

    The authors present their result of a two-year follow-up of 106 patients to whom an intra-arterial perfusion of prostaglandin E1 was administered, as limb salvage procedure. The patients were in the IIIrd and IVth stage of occlusive diseases by Fountain, and surgical reconstructions were not possible. All patients were divided into five groups: A--diabetic angiopathy (5), B--distal form of atherosclerosis (40), C--diabetic angiopathy and atherosclerosis (45), D--Burger disease (10) and E--adjuvant therapy in reconstruction with poor run-off (6). The Doppler sonographic and angiographic measurements were performed. After transcutaneous (16 cases), or intraoperative (90 cases) introduction of the catheter into superficial of profunda femoral artery, a continuous intraarterial administration of prostaglandin E1 was carried out in a dose of 10 nanograms/kg body weight/minute (total dosage 3000 nanograms). The patients were controlled immediately after the treatment, as well as 1, 3, 6, 12, 24 and 36 months after the treatment. In efficiency of the treatment was estimated on the following basis: elimination of rest pain, healing of trophic ulceration and demarcation of gangrenous processes. Our late results of intra-arterial administration of prostaglandin E1 proved to be a very successful limb salvage procedure. The treatment was more successful in a connections between the upper knee arterial net and pedal arterial arches were preserved. PMID:1641706

  17. Major role of adipocyte prostaglandin E2 in lipolysis-induced macrophage recruitment.

    PubMed

    Hu, Xiaoqian; Cifarelli, Vincenza; Sun, Shishuo; Kuda, Ondrej; Abumrad, Nada A; Su, Xiong

    2016-04-01

    Obesity induces accumulation of adipose tissue macrophages (ATMs), which contribute to both local and systemic inflammation and modulate insulin sensitivity. Adipocyte lipolysis during fasting and weight loss also leads to ATM accumulation, but without proinflammatory activation suggesting distinct mechanisms of ATM recruitment. We examined the possibility that specific lipid mediators with anti-inflammatory properties are released from adipocytes undergoing lipolysis to induce macrophage migration. In the present study, we showed that conditioned medium (CM) from adipocytes treated with forskolin to stimulate lipolysis can induce migration of RAW 264.7 macrophages. In addition to FFAs, lipolytic stimulation increased release of prostaglandin E2(PGE2) and prostaglandin D2(PGD2), reflecting cytosolic phospholipase A2α activation and enhanced cyclooxygenase (COX) 2 expression. Reconstituted medium with the anti-inflammatory PGE2potently induced macrophage migration while different FFAs and PGD2had modest effects. The ability of CM to induce macrophage migration was abolished by treating adipocytes with the COX2 inhibitor sc236 or by treating macrophages with the prostaglandin E receptor 4 antagonist AH23848. In fasted mice, macrophage accumulation in adipose tissue coincided with increases of PGE2levels and COX1 expression. Collectively, our data show that adipocyte-originated PGE2with inflammation suppressive properties plays a significant role in mediating ATM accumulation during lipolysis. PMID:26912395

  18. Methylmercury Alters the Activities of Hsp90 Client Proteins, Prostaglandin E Synthase/p23 (PGES/23) and nNOS

    PubMed Central

    Caito, Samuel; Zeng, Heng; Aschner, Judy L.; Aschner, Michael

    2014-01-01

    Methylmercury (MeHg) is a persistent pollutant with known neurotoxic effects. We have previously shown that astrocytes accumulate MeHg and play a prominent role in mediating MeHg toxicity in the central nervous system (CNS) by altering glutamate signaling, generating oxidative stress, depleting glutathione (GSH) and initiating lipid peroxidation. Interestingly, all of these pathways can be regulated by the constitutively expressed, 90-kDa heat shock protein, Hsp90. As Hsp90 function is regulated by oxidative stress, we hypothesized that MeHg disrupts Hsp90-client protein functions. Astrocytes were treated with MeHg and expression of Hsp90, as well as the abundance of complexes of Hsp90-neuronal nitric oxide synthase (nNOS) and Hsp90-prostaglandin E synthase/p23 (PGES/p23) were assessed. MeHg exposure decreased Hsp90 protein expression following 12 h of treatment while shorter exposures had no effect on Hsp90 protein expression. Interestingly, following 1 or 6 h of MeHg exposure, Hsp90 binding to PGES/p23 or nNOS was significantly increased, resulting in increased prostaglandin E2 (PGE2) synthesis from MeHg-treated astrocytes. These effects were attenuated by the Hsp90 antagonist, geldanmycin. NOS activity was increased following MeHg treatment while cGMP formation was decreased. This was accompanied by an increase in •O2− and H2O2 levels, suggesting that MeHg uncouples NO formation from NO-dependent signaling and increases oxidative stress. Altogether, our data demonstrates that Hsp90 interactions with client proteins are increased following MeHg exposure, but over time Hsp90 levels decline, contributing to oxidative stress and MeHg-dependent excitotoxicity. PMID:24852575

  19. Direct Melanoma Cell Contact Induces Stromal Cell Autocrine Prostaglandin E2-EP4 Receptor Signaling That Drives Tumor Growth, Angiogenesis, and Metastasis.

    PubMed

    Inada, Masaki; Takita, Morichika; Yokoyama, Satoshi; Watanabe, Kenta; Tominari, Tsukasa; Matsumoto, Chiho; Hirata, Michiko; Maru, Yoshiro; Maruyama, Takayuki; Sugimoto, Yukihiko; Narumiya, Shuh; Uematsu, Satoshi; Akira, Shizuo; Murphy, Gillian; Nagase, Hideaki; Miyaura, Chisato

    2015-12-11

    The stromal cells associated with tumors such as melanoma are significant determinants of tumor growth and metastasis. Using membrane-bound prostaglandin E synthase 1 (mPges1(-/-)) mice, we show that prostaglandin E2 (PGE2) production by host tissues is critical for B16 melanoma growth, angiogenesis, and metastasis to both bone and soft tissues. Concomitant studies in vitro showed that PGE2 production by fibroblasts is regulated by direct interaction with B16 cells. Autocrine activity of PGE2 further regulates the production of angiogenic factors by fibroblasts, which are key to the vascularization of both primary and metastatic tumor growth. Similarly, cell-cell interactions between B16 cells and host osteoblasts modulate mPGES-1 activity and PGE2 production by the osteoblasts. PGE2, in turn, acts to stimulate receptor activator of NF-κB ligand expression, leading to osteoclast differentiation and bone erosion. Using eicosanoid receptor antagonists, we show that PGE2 acts on osteoblasts and fibroblasts in the tumor microenvironment through the EP4 receptor. Metastatic tumor growth and vascularization in soft tissues was abrogated by an EP4 receptor antagonist. EP4-null Ptger4(-/-) mice do not support B16 melanoma growth. In vitro, an EP4 receptor antagonist modulated PGE2 effects on fibroblast production of angiogenic factors. Our data show that B16 melanoma cells directly influence host stromal cells to generate PGE2 signals governing neoangiogenesis and metastatic growth in bone via osteoclast erosive activity as well as angiogenesis in soft tissue tumors. PMID:26475855

  20. Stimulus specificity of prostaglandin inhibition of rabbit polymorphonuclear leukocyte lysosomal enzyme release and superoxide anion production.

    PubMed Central

    Fantone, J. C.; Marasco, W. A.; Elgas, L. J.; Ward, P. A.

    1984-01-01

    Prostaglandins (PGs) of the E series and PGI2 have been shown to inhibit acute inflammatory reactions in vivo and polymorphonuclear leukocyte (PMN), chemotaxis, lysosomal enzyme release, and superoxide anion (O-2) production in vitro. This inhibition of neutrophil stimulation by PGEs and PGI2 has been correlated with their ability to increase intracellular cyclic adenosine monophosphate (cAMP) levels. However, the mechanism(s) by which PGEs and PGI2 alter the complex biochemical and biophysical events associated with stimulus-response coupling in the neutrophil are not clear. It is reported here that both PGEs and PGI2 in micromolar concentrations inhibit formyl-methionyl-leucyl-phenylalanine (FMLP)- and zymosan-induced lysosomal enzyme secretion and superoxide anion production in a dose-dependent manner. No preincubation time of PMNs with the prostaglandins is required for inhibition. Addition of PGEs 10 seconds or later after FMLP stimulation does not alter the biologic response of the neutrophils to the stimulus, suggesting that the prostaglandin inhibition effects early events associated with stimulus-response coupling in the neutrophil. Prostaglandin inhibition of lysosomal enzyme release by the calcium ionophore A23187 was overcome by increasing the extracellular ionophore and/or calcium concentration, suggesting that PGs may modulate intracellular free calcium levels in a manner similar to that observed with platelets. Inhibition of phorbol myristate acetate (PMA)-induced neutrophil lysosomal enzyme secretion by PGEs and PGI2 was overcome by increasing concentrations of PMA. However, neither PGEs nor PGI2 altered O-2 production by PMA-treated neutrophils. These data indicate a dissociation between PMA-stimulated O-2 production and lysosomal enzyme release. These findings are consistent with the hypothesis that inhibition of neutrophil stimulation by PGEs and PGI2 is a result of increased intracellular cyclic AMP levels and modulation of calcium

  1. Prostaglandin potentiates 5-HT responses in stomach and ileum innervating visceral afferent sensory neurons

    SciTech Connect

    Kim, Sojin; Jin, Zhenhua; Lee, Goeun; Park, Yong Seek; Park, Cheung-Seog; Jin, Young-Ho

    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

  2. Induction of cyclo-oxygenase-2 mRNA by prostaglandin E2 in human prostatic carcinoma cells

    NASA Technical Reports Server (NTRS)

    Tjandrawinata, R. R.; Dahiya, R.; Hughes-Fulford, M.

    1997-01-01

    Prostaglandins are synthesized from arachidonic acid by the enzyme cyclo-oxygenase. There are two isoforms of cyclooxygenases: COX-1 (a constitutive form) and COX-2 (an inducible form). COX-2 has recently been categorized as an immediate-early gene and is associated with cellular growth and differentiation. The purpose of this study was to investigate the effects of exogenous dimethylprostaglandin E2 (dmPGE2) on prostate cancer cell growth. Results of these experiments demonstrate that administration of dmPGE2 to growing PC-3 cells significantly increased cellular proliferation (as measured by the cell number), total DNA content and endogenous PGE2 concentration. DmPGE2 also increased the steady-state mRNA levels of its own inducible synthesizing enzyme, COX-2, as well as cellular growth to levels similar to those seen with fetal calf serum and phorbol ester. The same results were observed in other human cancer cell types, such as the androgen-dependent LNCaP cells, breast cancer MDA-MB-134 cells and human colorectal carcinoma DiFi cells. In PC-3 cells, the dmPGE2 regulation of the COX-2 mRNA levels was both time dependent, with maximum stimulation seen 2 h after addition, and dose dependent on dmPGE2 concentration, with maximum stimulation seen at 5 microg ml(-1). The non-steroidal anti-inflammatory drug flurbiprofen (5 microM), in the presence of exogenous dmPGE2, inhibited the up-regulation of COX-2 mRNA and PC-3 cell growth. Taken together, these data suggest that PGE2 has a specific role in the maintenance of human cancer cell growth and that the activation of COX-2 expression depends primarily upon newly synthesized PGE2, perhaps resulting from changes in local cellular PGE2 concentrations.

  3. Prostaglandin transporters ABCC4 and SLCO2A1 in the uterine endometrium and conceptus during pregnancy in pigs.

    PubMed

    Seo, Heewon; Choi, Yohan; Shim, Jangsoo; Yoo, Inkyu; Ka, Hakhyun

    2014-05-01

    Prostaglandins (PGs) are involved in many reproductive activities including luteolysis, maternal recognition of pregnancy, endometrial gene expression, conceptus development, and parturition in domestic animals. However, mechanisms by which PGE2 and PGF2alpha are modulated in the uterine endometrium and expression of ABCC4 and SLCO2A1, responsible for efficient transport of PGs across the cell membrane, in the endometrium during the estrous cycle and pregnancy are not fully understood in pigs. Therefore, we determined expression of ABCC4 and SLCO2A1, genes involved in transport of PGE2 and PGF2alpha in the uterine endometrium during the estrous cycle and pregnancy in pigs. ABCC4 and SLCO2A1 mRNAs were expressed in the uterine endometrium, most abundantly on Day 12 of pregnancy and during late pregnancy. Expression of ABCC4 mRNA and protein was localized mainly to uterine luminal epithelial (LE) and glandular epithelial (GE) cells, and expression of SLCO2A1 mRNA and protein was expressed primarily in uterine LE and blood vessels. Expression of ABCC4 and SLCO2A1 mRNAs was also detected in conceptuses during early pregnancy. In addition, explant culture experiments showed that increasing doses of interleukin 1B (IL1B) with estrogen and progesterone increased levels of ABCC4 and SLCO2A1 mRNAs in the uterine endometrium. These results indicate that expression of genes responsible for transport of PGE2 and PGF2alpha are dynamically regulated in the uterine endometrium during pregnancy and that ABCC4 and SLCO2A1 play critical roles in supporting the establishment and maintenance of pregnancy by regulating PG transport at the maternal-fetal interface in pigs. PMID:24695625

  4. Anti-inflammatory activity of Nerium indicum by inhibition of prostaglandin E2 in murine splenic lymphocytes

    PubMed Central

    Dey, Priyankar; Chaudhuri, Tapas Kumar

    2015-01-01

    Objective: Nerium indicum Mill (syn. N. oleander L. and N. odorum Aiton; family: Apocynaceae) is a medicinal plant, used in the treatment of diverse ailments including various chronic inflammatory diseases in traditional medicine. We have previously demonstrated the immunomodulatory activity of a bioactive fraction of Nerium indicum leaf (NILE) by studying up-regulation of interleukin-2 (IL-2), IL-10, interferon-gamma and down regulation of IL-4, tumor necrosis factor-alpha (TNF-α), nitric oxide, cyclooxygenase-1 (COX-1) and COX-2 activities. Therefore, this study aimed to confirm the anti-inflammatory activity of NILE by inhibition of prostaglandin E2 (PGE2) activity in murine splenic lymphocytes in vitro. Materials and Methods: Murine lymphocytes were isolated from spleen and stimulated with 5 ΅g/mL concanavalin A in RPMI-1640, supplemented with 50 U/mL penicillin, 50 U/mL streptomycin, 50 U/mL nystatin and 10% fetal bovine serum. Different concentrations (0–80 μg/mL) of NILE were added and the cells were cultured for 48 h. The culture supernatants were thereafter collected by centrifugation and assayed for expression of PGE2 level. The data were analyzed statistically. Results: The results demonstrated a 2.26-fold inhibition of PGE2 level at 80 μg/mL of NILE. Half maximum inhibitory concentration (IC50) was calculated to be 44.95 ± 0.45 ΅g/mL. Linear correlation analysis of the dose-dependent PGE2 inhibition with other pro- and anti-inflammatory mediators demonstrated high inter-correlation between the parameters. Conclusions: Thus, the present study remains in accordance with our previous report and confirms the anti-inflammatory claim of N. indicum, mentioned in the traditional medicine. PMID:26288481

  5. Bleomycin-induced pulmonary fibrosis in hamsters. An alveolar macrophage product increases fibroblast prostaglandin E2 and cyclic adenosine monophosphate and suppresses fibroblast proliferation and collagen production.

    PubMed Central

    Clark, J G; Kostal, K M; Marino, B A

    1983-01-01

    Bleomycin-induced pulmonary fibrosis in hamsters is associated with collagen accumulation that results from increased lung collagen synthesis rates. However, 1-2 wk after intratracheal instillation of bleomycin, lung collagen synthesis rates decline toward control values. To evaluate the potential role of the bronchoalveolar macrophage in regulating lung collagen production, we studied the effects of macrophages from normal and bleomycin-treated hamsters upon fibroblasts in vitro. We observed: (a) Medium from macrophage cultures decreased fibroblast [3H]thymidine incorporation and nondialyzable [3H]hydroxyproline production in a dose-dependent manner. Fibroblast cell counts were decreased in exposed cultures, and fibroblast viability was unchanged. Procollagen prolyl hydroxylation and prolyl-transfer RNA-specific activity were not altered by macrophage medium; this indicates that [3H]hydroxyproline reflects collagen production rate under the experimental conditions. (b) The suppressive effect of macrophage medium was selective for collagen since collagen production decreased more than noncollagen protein production. (c) Medium from bleomycin-treated hamster macrophages suppressed fibroblast proliferation and collagen production to a greater degree than medium from normal hamster macrophages. (d) Fibroblast suppression by macrophage medium was associated with increased fibroblast endogenous prostaglandin E2 production and intracellular cyclic AMP (cAMP). (e) Incubation of fibroblasts with indomethacin before exposure completely inhibited prostaglandin E2 production and increases in cAMP, and eliminated suppression of fibroblast proliferation and collagen production. The macrophage-derived suppressive factor has an apparent molecular weight of 20,000-30,000 and is heat stable. It does not appear to be species restricted since both hamster and human lung fibroblasts are similarly suppressed. It is at least in part preformed in macrophages obtained by lavage, but its

  6. The Prostaglandin F Synthase Activity of the Human Aldose Reductase AKR1B1 Brings New Lenses to Look at Pathologic Conditions

    PubMed Central

    Bresson, Eva; Lacroix-Pépin, Nicolas; Boucher-Kovalik, Sofia; Chapdelaine, Pierre; Fortier, Michel A.

    2012-01-01

    Prostaglandins are important regulators of female reproductive functions to which aldose reductases exhibiting hydroxysteroid dehydrogenase activity also contribute. Our work on the regulation of reproductive function by prostaglandins (PGs), lead us to the discovery that AKR1B5 and later AKR1B1were highly efficient and physiologically relevant PGF synthases. PGE2 and PGF2α are the main prostanoids produced in the human endometrium and proper balance in their relative production is important for normal menstruation and optimal fertility. Recent evidence suggests that PGE2/EP2 and PGF2α/FP may constitute a functional dyad with physiological relevance comparable to the prostacyclin-thromboxane dyad in the vascular system. We have recently reported that AKR1B1 was expressed and modulated in association with PGF2α production in response to IL-1β in the human endometrium. In the present study, we show that the human AKR1B1 (gene ID: 231) also known as ALDR1 or ALR2 is a functional PGF2α synthase in different models of living cells and tissues. Using human endometrial cells, prostate, and vascular smooth muscle cells, cardiomyocytes and endothelial cells we demonstrate that IL-1β is able to up regulate COX-2 and AKR1B1 proteins as well as PGF2α production under normal glucose concentrations. We show that the promoter activity of AKR1B1 gene is increased by IL-1β particularly around the multiple stress response region containing two putative antioxidant response elements adjacent to TonE and AP1. We also show that AKR1B1 is able to regulate PGE2 production through PGF2α acting on its FP receptor and that aldose reductase inhibitors like alrestatin, Statil (ponalrestat), and EBPC exhibit distinct and characteristic inhibition of PGF2α production in different cell models. The PGF synthase activity of AKR1B1 represents a new and important target to regulate ischemic and inflammatory responses associated with several human pathologies. PMID:22654757

  7. Seminal plasma induces prostaglandin-endoperoxide synthase (PTGS) 2 expression in immortalized human vaginal cells: involvement of semen prostaglandin E2 in PTGS2 upregulation.

    PubMed

    Joseph, Theresa; Zalenskaya, Irina A; Sawyer, Lyn C; Chandra, Neelima; Doncel, Gustavo F

    2013-01-01

    Inflammation of the cervicovaginal mucosa is considered a risk factor for HIV infection in heterosexual transmission. In this context, seminal plasma (SP) may play an important role that is not limited to being the main carrier for the virions. It is known that SP induces an inflammatory reaction in the cervix called postcoital leukocytic reaction, which has been associated with promotion of fertility. The mechanisms by which SP triggers this reaction, however, have not been clearly established. Previously we reported the expression of prostaglandin-endoperoxide synthase 2 (PTGS2), also known as cyclooxygenase 2 (COX-2), in human vaginal cells in response to toll-like receptor (TLR) ligands and other proinflammatory stimuli. In this study, we demonstrate that SP induces transcriptional and translational increase of COX-2 expression in human vaginal cells and cervicovaginal tissue explants. Furthermore, SP potentiates vaginal PTGS2 expression induced by other proinflammatory stimulants, such as TLR ligands and a vaginal mucosal irritant (nonoxynol-9) in a synergistic manner. SP-induced PTGS2 expression is mediated by intracellular signaling pathways involving MAPKs and NF-κB. Using fractionation and functional analysis, seminal prostaglandin (PG)-E(2) was identified as a one of the major factors in PTGS2 induction. Given the critical role of this PG-producing enzyme in mucosal inflammatory processes, the finding that SP induces and potentiates the expression of PTGS2 in cervicovaginal cells and tissues has mechanistic implications for the role of SP in fertility-associated mucosal leukocytic reaction and its potential HIV infection-enhancing effect. PMID:23153564

  8. Prostaglandin-E1 has a protective effect on renal ischemia/reperfusion-induced oxidative stress and inflammation mediated gastric damage in rats.

    PubMed

    Gezginci-Oktayoglu, Selda; Orhan, Nurcan; Bolkent, Sehnaz

    2016-07-01

    Gastrointestinal complications are frequent in renal transplant recipients. In this regard, renal ischemia/reperfusion injury (IRI)-induced gastric damage seems to be important and there is no data available on the mechanism of this pathology. Because of its anti-inflammatory and anti-oxidant properties, it can be suggested that prostaglandin-E1 (PGE1) protects cells from renal IRI-induced gastric damage. The aim of this study was to investigate the molecular mechanisms of gastric damage induced by renal IRI and the effect of PGE1 on these mechanisms. We set an experiment with four different animal groups: physiological saline-injected and sham-operated rats, PGE1 (20μg/kg)-administered and sham operated rats, renal IRI subjected rats, and PGE1-administered and renal IRI subjected rats. The protective effect of PGE1 on renal IRI-induced gastric damage was determined based on reduced histological damage and lactate dehydrogenase activity. Moreover, we demonstrated that PGE1 shows its protective effect through reducing the production of reactive oxygen species and malondialdehyde levels. During histological examination, we observed the presence of common mononuclear cell infiltration. Therefore, pro-inflammatory cytokines tumor necrosis factor-α and interleukin-1β levels were measured and it has been shown that PGE1 suppressed both cytokines. Furthermore, it was found that PGE1 reduced the number of NF-κB(+) and caspase-3(+) inflammatory cells, and also NF-κB DNA-binding activity, while increasing proliferating cell nuclear antigen(+) epithelial cells in the stomach tissue of rats subjected to renal IR. Our data showed that PGE1 has a protective effect on renal IRI-induced oxidative stress and inflammation mediated gastric damage in rats. PMID:27135545

  9. Il-1β and prostaglandin E2 attenuate the hypercapnic as well as the hypoxic respiratory response via prostaglandin E receptor type 3 in neonatal mice.

    PubMed

    Siljehav, Veronica; Shvarev, Yuri; Herlenius, Eric

    2014-11-01

    Prostaglandin E2 (PGE2) serves as a critical mediator of hypoxia, infection, and apnea in term and preterm babies. We hypothesized that the prostaglandin E receptor type 3 (EP3R) is the receptor responsible for PGE2-induced apneas. Plethysmographic recordings revealed that IL-1β (ip) attenuated the hypercapnic response in C57BL/6J wild-type (WT) but not in neonatal (P9) EP3R(-/-) mice (P < 0.05). The hypercapnic responses in brain stem spinal cord en bloc preparations also differed depending on EP3R expression whereby the response was attenuated in EP3R(-/-) preparations (P < 0.05). After severe hypoxic exposure in vivo, IL-1β prolonged time to autoresuscitation in WT but not in EP3R(-/-) mice. Moreover, during severe hypoxic stress EP3R(-/-) mice had an increased gasping duration (P < 0.01) as well as number of gasps (P < 0.01), irrespective of intraperitoneal treatment, compared with WT mice. Furthermore, EP3R(-/-) mice exhibited longer hyperpneic breathing efforts when exposed to severe hypoxia (P < 0.01). This was then followed by a longer period of secondary apnea before autoresuscitation occurred in EP3R(-/-) mice (P < 0.05). In vitro, EP3R(-/-) brain stem spinal cord preparations had a prolonged respiratory burst activity during severe hypoxia accompanied by a prolonged neuronal arrest during recovery in oxygenated medium (P < 0.05). In conclusion, PGE2 exerts its effects on respiration via EP3R activation that attenuates the respiratory response to hypercapnia as well as severe hypoxia. Modulation of the EP3R may serve as a potential therapeutic target for treatment of inflammatory and hypoxic-induced detrimental apneas and respiratory disorders in neonates. PMID:25213632

  10. Evaluation of pro-inflammatory markers plasma C-reactive protein and urinary prostaglandin-E2 metabolite in colorectal adenoma risk.

    PubMed

    Davenport, James R; Cai, Qiuyin; Ness, Reid M; Milne, Ginger; Zhao, Zhiguo; Smalley, Walter E; Zheng, Wei; Shrubsole, Martha J

    2016-08-01

    C-reactive protein (CRP) is a pro-inflammatory protein with potential as a biomarker in predicting colon cancer risk. However, little is known regarding its association with risk of colorectal adenomas, particularly by subtypes. We conducted a colonoscopy-based matched case-control study to assess whether elevated plasma CRP levels may be associated with colorectal adenoma risk and further whether this association may be modified by urinary prostaglandin E2 metabolite (PGE-M), a biomarker of systemic prostaglandin E2 production. Included in the study were 226 cases with a single small tubular adenoma, 198 cases with multiple small tubular adenomas, 283 cases with at least one advanced adenoma, and 395 polyp-free controls. No apparent association between CRP level and risk of single small tubular adenomas was found (ptrend  = 0.59). A dose-response relationship with CRP level was observed for risk of either multiple small tubular adenomas (OR = 2.01, 95%CI = 1.10-3.68 for the highest versus lowest tertile comparison; ptrend   = 0.03) or advanced adenomas (OR = 1.81, 95%CI = 1.10-2.96 for the highest versus lowest tertile comparison; ptrend  = 0.02). In a joint analysis of CRP level and PGE-M, risk of multiple or advanced adenoma was greatest among those with highest levels of both CRP and PGE-M in comparison to those with low CRP and low PGE-M (OR = 3.72, 95%CI = 1.49-9.72). Our results suggest that elevated CRP, particularly in the context of concurrent elevated PGE-M, may be a biomarker of multiple or advanced adenoma risk in a screening age population. © 2015 Wiley Periodicals, Inc. PMID:26333108

  11. Stimulation of prostaglandin E/sub 2/ production by phorbol esters and epidermal growth factor in porcine thyroid cells

    SciTech Connect

    Kasai, K.; Hiraiwa, M.; Emoto, T.; Akimoto, K.; Takaoka, T.; Shimoda, S.I.

    1987-07-13

    Effects of phorbol esters and epidermal growth factor (EGF) on prostaglandin E/sub 2/ production by cultured porcine thyroid cells were examined. Both phorbol 12-myristate 13-acetate (PMA) and EGF stimulated prostaglandin E/sub 2/ production by the cells in dose related fashion. PMA stimulated prostaglandin E/sub 2/ production over fifty-fold with the dose of 10/sup -7/ M compared with control. EGF (10/sup -7/ M) also stimulated it about ten-fold. The ED/sub 50/ values of PMA and EGF were respectively around 1 x 10/sup -9/ M and 5 x 10/sup -10/ M. Thyroid stimulating hormone (TSH), however, did not stimulate prostaglandin E/sub 2/ production from 1 to 24-h incubation. The release of radioactivity from (/sup 3/H)-arachidonic acid prelabeled cells was also stimulated by PMA and EGF, but not by TSH. These results indicate that both PMA and EGF are potent stimulators of prostaglandin E/sub 2/ production, associated with the activity to stimulate arachidonic acid release in porcine thyroid cells. 36 references, 2 figures, 1 table.

  12. Blockade of prostaglandin E1 hyperthermia by sodium salicylate given into the ventral septal area of the rat brain.

    PubMed Central

    Alexander, S J; Cooper, K E; Veale, W L

    1987-01-01

    1. Sodium salicylate (30.0 micrograms microliter-1) or artificial cerebrospinal fluid (ACSF) was infused bilaterally into the ventral septal area (v.s.a.) of the unrestrained rat for 1 h before and 1 h after the injection of prostaglandin E1 at a concentration of 20.0 ng microliter-1 into a lateral cerebral ventricle. 2. During control (ACSF) infusions, 200.0 ng of prostaglandin E1 evoked a hyperthermic response (0.95 +/- 0.16 degrees C). During sodium salicylate infusions, the prostaglandin E1-evoked hyperthermia was significantly reduced (P less than 0.025) to 0.31 +/- 0.16 degrees C. 3. The fever index (degrees C h for 1.0 h) during the infusion of sodium salicylate was reduced 66% below that of control infusions (P less than 0.01). 4. These data indicate that sodium salicylate infused in the v.s.a. of rats can antagonize a prostaglandin E-evoked hyperthermia. This suggests that there may be an additional mechanism of action for sodium salicylate antipyresis other than inhibition of prostaglandin E synthesis. PMID:3656145

  13. Prostaglandin E2 accelerates invasion by upregulating Snail in hepatocellular carcinoma cells.

    PubMed

    Zhang, Min; Zhang, Hai; Cheng, Shanyu; Zhang, Dengcai; Xu, Yan; Bai, Xiaoming; Xia, Shukai; Zhang, Li; Ma, Juan; Du, Mingzhan; Wang, Yipin; Wang, Jie; Chen, Meng; Leng, Jing

    2014-07-01

    Our previous studies showed that prostaglandin E2 (PGE2) promotes hepatoma cell growth and migration, as well as invasion; however, the precise mechanism remains elusive. Snail and p65 protein levels were detected in human samples with hepatocellular carcinoma (HCC) by immunohistochemistry (IHC) staining. HCC cell lines (Huh-7 and Hep3B) were used for in vitro experiments. PGE2/Akt/NF-κB pathway was investigated in Huh-7 and Hep3B cells after treatment with PGE2, EP4 receptor (EP4R) agonist, Akt inhibitor, and NF-κB inhibitor, respectively, by real-time reverse transcription (RT)-PCR, Western blotting, and immunofluorescence (IF) staining. In vitro cell invasion assay was performed to evaluate the effect of PGE2 on tumor invasiveness. Knockdown of EP4R was carried out in Huh-7 cells through plasmid-based small interfering RNA (siRNA) approach to confirm the regulation of PGE2 on Snail by EP4R. Dual luciferase reporter assay was performed to assess Snail promoter activity in Huh-7 cell after treatment with EP4R agonist. We found that the protein levels of Snail were higher in HCC tissues than those in control and that PGE2 and EP4R agonist treatment significantly increased Snail expression in Huh-7 and Hep3B cells. EP4R agonist also profoundly promoted invasiveness of Huh-7 cells. Knockdown of the EP4R by siRNA completely blocked the PGE2-induced upregulation of Snail expression and reduced invasiveness of Huh-7 cells. We failed to find that EP4R-induced upregulation of Snail was reversed by inhibition of cAMP response element-binding protein (CREB), a canonical downstream target of EP4R. Alternatively, EP4R agonist treatment significantly increased the levels of phosphorylated EGFR and Akt both in Huh-7 and Hep3B cells. AG1478, an EGFR inhibitor, blocked the phosphorylation of Akt. The levels of phosphorylated IκB increased in Huh-7 cells after treatment with EP4R agonist for 30 min. The levels of phosphorylated p65 started to increase in Huh-7 cells treated

  14. Mitogen-activated Protein Kinase (MAPK) Activated by Prostaglandin E2 Phosphorylates Connexin 43 and Closes Osteocytic Hemichannels in Response to Continuous Flow Shear Stress.

    PubMed

    Riquelme, Manuel A; Burra, Sirisha; Kar, Rekha; Lampe, Paul D; Jiang, Jean X

    2015-11-20

    Cx43 hemichannels serve as a portal for the release of prostaglandins, a critical process in mediating biological responses of mechanical loading on bone formation and remodeling. We have previously observed that fluid flow shear stress (FFSS) opens hemichannels; however, sustained FFSS results in hemichannel closure, as continuous opening of hemichannels is detrimental to cell viability and bone remodeling. However, the mechanism that regulates the closure of the hemichannels is unknown. Here, we show that activation of p44/42 ERK upon continuous FFSS leads to Cx43 phosphorylation at Ser(279)-Ser(282), sites known to be phosphorylated sites by p44/42 MAPK. Incubation of osteocytic MLO-Y4 cells with conditioned media (CM) collected after continuous FFSS increased MAPK-dependent phosphorylation of Cx43. CM treatment inhibited hemichannel opening and this inhibition was reversed when cells were pretreated with the MAPK pathway inhibitor. We found that prostaglandin E2 (PGE2) accumulates in the CM in a time-dependent manner. Treatment with PGE2 increased phospho-p44/42 ERK levels and also Cx43 phosphorylation at Ser(279)-Ser(282) sites. Depletion of PGE2 from CM, and pre-treatment with a p44/42 ERK pathway-specific inhibitor, resulted in a complete inhibition of ERK-dependent Cx43 phosphorylation and attenuated the inhibition of hemichannels by CM and PGE2. Consistently, the opening of hemichannels by FFSS was blocked by PGE2 and CM and this blockage was reversed by U0126 and the CM depleted of PGE2. A similar observation was also obtained in isolated primary osteocytes. Together, results from this study suggest that extracellular PGE2 accumulated after continuous FFSS is responsible for activation of p44/42 ERK signaling and subsequently, direct Cx43 phosphorylation by activated ERK leads to hemichannel closure. PMID:26442583

  15. Recombinant interleukin-1β dilates steelhead trout coronary microvessels: effect of temperature and role of the endothelium, nitric oxide and prostaglandins

    PubMed Central

    Costa, Isabel A. S. F.; Hein, Travis W.; Secombes, Christopher J.; Gamperl, A. Kurt

    2015-01-01

    ABSTRACT Interleukin (IL)-1β is associated with hypotension and cardiovascular collapse in mammals during heat stroke, and the mRNA expression of this pro-inflammatory cytokine increases dramatically in the blood of Atlantic cod (Gadus morhua) at high temperatures. These data suggest that release of IL-1β at high temperatures negatively impacts fish cardiovascular function and could be a primary determinant of upper thermal tolerance in this taxa. Thus, we measured the concentration-dependent response of isolated steelhead trout (Oncorhynchus mykiss) coronary microvessels (<150 μm in diameter) to recombinant (r) IL-1β at two temperatures (10 and 20°C). Recombinant IL-1β induced a concentration-dependent vasodilation with vessel diameter increasing by approximately 8 and 30% at 10−8 and 10−7 mol l−1, respectively. However, this effect was not temperature dependent. Both vessel denudation and cyclooxygenase blockade (by indomethacin), but not the nitric oxide (NO) antagonist L-NIO, inhibited the vasodilator effect of rIL-1β. In contrast, the concentration-dependent dilation caused by the endothelium-dependent calcium ionophore A23187 was completely abolished by L-NIO and indomethacin, suggesting that both NO and prostaglandin signaling mechanisms exist in the trout coronary microvasculature. These data: (1) are the first to demonstrate a functional link between the immune and cardiovascular systems in fishes; (2) suggest that IL-1β release at high temperatures may reduce systemic vascular resistance, and thus, the capacity of fish to maintain blood pressure; and (3) provide evidence that both NO and prostaglandins play a role in regulating coronary vascular tone, and thus, blood flow. PMID:26026045

  16. Myeloid Cell Prostaglandin E2 Receptor EP4 Modulates Cytokine Production but Not Atherogenesis in a Mouse Model of Type 1 Diabetes

    PubMed Central

    Vallerie, Sara N.; Kramer, Farah; Barnhart, Shelley; Kanter, Jenny E.; Breyer, Richard M.; Andreasson, Katrin I.; Bornfeldt, Karin E.

    2016-01-01

    Type 1 diabetes mellitus (T1DM) is associated with cardiovascular complications induced by atherosclerosis. Prostaglandin E2 (PGE2) is often raised in states of inflammation, including diabetes, and regulates inflammatory processes. In myeloid cells, a key cell type in atherosclerosis, PGE2 acts predominately through its Prostaglandin E Receptor 4 (EP4; Ptger4) to modulate inflammation. The effect of PGE2-mediated EP4 signaling specifically in myeloid cells on atherosclerosis in the presence and absence of diabetes is unknown. Because diabetes promotes atherosclerosis through increased arterial myeloid cell accumulation, we generated a myeloid cell-targeted EP4-deficient mouse model (EP4M-/-) of T1DM-accelerated atherogenesis to investigate the relationship between myeloid cell EP4, inflammatory phenotypes of myeloid cells, and atherogenesis. Diabetic mice exhibited elevated plasma PGE metabolite levels and elevated Ptger4 mRNA in macrophages, as compared with non-diabetic littermates. PGE2 increased Il6, Il1b, Il23 and Ccr7 mRNA while reducing Tnfa mRNA through EP4 in isolated myeloid cells. Consistently, the stimulatory effect of diabetes on peritoneal macrophage Il6 was mediated by PGE2-EP4, while PGE2-EP4 suppressed the effect of diabetes on Tnfa in these cells. In addition, diabetes exerted effects independent of myeloid cell EP4, including a reduction in macrophage Ccr7 levels and increased early atherogenesis characterized by relative lesional macrophage accumulation. These studies suggest that this mouse model of T1DM is associated with increased myeloid cell PGE2-EP4 signaling, which is required for the stimulatory effect of diabetes on IL-6, markedly blunts the effect of diabetes on TNF-α and does not modulate diabetes-accelerated atherogenesis. PMID:27351842

  17. Importance of endogenous prostaglandins for the toxicity of cyclosporin A to rat endocrine and exocrine pancreas?

    PubMed Central

    Rünzi, M; Peskar, B M; von Schönfeld, J; Müller, M K

    1992-01-01

    Previous work has shown that cyclosporin A is toxic to the endocrine and exocrine pancreas. The aim of this study was to examine whether endogenous eicosanoids play a role in controlling cyclosporin A induced toxicity. Rats were treated for eight days with indomethacin (2 mg/kg, twice daily) in addition to cyclosporin A (5 or 10 mg/kg daily). Effects of drug treatments on exocrine (as assessed by amylase and protein secretion into the pancreatic juice) and endocrine (as assessed by the glucose dependent insulin release) pancreatic functions, and pancreatic formation of prostaglandins and thromboxane were evaluated. Treatment with cyclosporin A in the doses used did not inhibit eicosanoid formation by the pancreatic tissue ex vivo. Indomethacin caused significant inhibition of pancreatic formation of prostaglandin E2, 6k prostaglandin F1 alpha and thromboxane B2. Combined treatment with indomethacin and cyclosporin A (5 or 10 mg/kg) augmented cyclosporin A induced pancreatic toxicity with further impairment of insulin release, amylase secretion, and pancreatic juice protein content, but did not result in more pronounced inhibition of pancreatic eicosanoid formation. The increased toxicity of the combined treatment was, however, associated with raised cyclosporin A whole blood concentrations. The data suggest that the potentiation of pancreatic toxicity of cyclosporin A observed during coadministration of indomethacin is not the result of suppression of endogenous pancreatic eicosanoid biosynthesis, but more likely results from altered cyclosporin A pharmacokinetic which may be caused by an interference of indomethacin with the hepatic cytochrome P-450 dependent monooxygenase involved in cyclosporin A metabolism. The possibility that coadministration of non-steroidal antiinflammatory drugs aggravates toxic effects in cyclosporin A treated patients should be considered. PMID:1280611

  18. Effects of Prostaglandin Cyclic Endoperoxides on the Lung Circulation of Unanesthetized Sheep

    PubMed Central

    Bowers, Ronald E.; Ellis, Earl F.; Brigham, Kenneth L.; Oates, John A.

    1979-01-01

    Although prostaglandins E2 and F2α have been suggested as mediators of the pulmonary hypertension seen after endotoxin infusion or during alveolar hypoxia, their precursors, the endoperoxides (prostaglandins G2 and H2) are much more potent vasoconstrictors in vitro. In this study we compared the effects of prostaglandin (PG)H2, a stable 9-methylene ether analogue of PGH2 (PGH2-A), PGE2, and PGF2α on pulmonary hemodynamics in awake sheep. The animals were prepared to allow for measurement of (a) lung lymph flow; (b) plasma and lymph protein concentration; (c) systemic and pulmonary vascular pressures; and (d) cardiac output. We also determined the effect of prolonged PGH2-A infusions on lung fluid balance and vascular permeability by indicator dilution methods, and by assessing the response of lung lymph. Both PGH2 and PGH2-A caused a dose-related increase in pulmonary artery pressure: 0.25 μg/kg × min tripled pulmonary vascular resistance without substantially affecting systemic pressures. Both were 100 times more potent than PGE2 or PGF2α in this preparation. PGH2-A, as our analysis of lung lymph and indicator dilution measurements show, does not increase the permeability of exchanging vessels in the lung to fluid and protein. It does, however, augment lung fluid transport by increasing hydrostatic pressure in the pulmonary circulation. We conclude: (a) that PGH2 is likely to be an important mediator of pulmonary vasoconstriction; (b) its effects are probably not a result of its metabolites PGE2 or PGF2α. PMID:762242

  19. Nitric oxide synthase stimulates prostaglandin synthesis and barrier function in C. parvum-infected porcine ileum.

    PubMed

    Gookin, Jody L; Duckett, Laurel L; Armstrong, Martha U; Stauffer, Stephen H; Finnegan, Colleen P; Murtaugh, Michael P; Argenzio, Robert A

    2004-09-01

    Cell culture models implicate increased nitric oxide (NO) synthesis as a cause of mucosal hyperpermeability in intestinal epithelial infection. NO may also mediate a multitude of subepithelial events, including activation of cyclooxygenases. We examined whether NO promotes barrier function via prostaglandin synthesis using Cryptosporidium parvum-infected ileal epithelium in residence with an intact submucosa. Expression of NO synthase (NOS) isoforms was examined by real-time RT-PCR of ileal mucosa from control and C. parvum-infected piglets. The isoforms mediating and mechanism of NO action on barrier function were assessed by measuring transepithelial resistance (TER) and eicosanoid synthesis by ileal mucosa mounted in Ussing chambers in the presence of selective and nonselective NOS inhibitors and after rescue with exogenous prostaglandins. C. parvum infection results in induction of mucosal inducible NOS (iNOS), increased synthesis of NO and PGE2, and increased mucosal permeability. Nonselective inhibition of NOS (NG-nitro-L-arginine methyl ester) inhibited prostaglandin synthesis, resulting in further increases in paracellular permeability. Baseline permeability was restored in the absence of NO by exogenous PGE2. Selective inhibition of iNOS [L-N6-(1-iminoethyl)-L-lysine] accounted for approximately 50% of NOS-dependent PGE2 synthesis and TER. Using an entire intestinal mucosa, we have demonstrated for the first time that NO serves as a proximal mediator of PGE2 synthesis and barrier function in C. parvum infection. Expression of iNOS by infected mucosa was without detriment to overall barrier function and may serve to promote clearance of infected enterocytes. PMID:15155179

  20. The cyclopentenone prostaglandin 15d-PGJ2 inhibits the NLRP1 and NLRP3 inflammasomes

    PubMed Central

    Maier, Nolan K.; Leppla, Stephen H.; Moayeri, Mahtab

    2015-01-01

    Inflammasomes are cytosolic protein complexes that respond to diverse danger signals by activating caspase-1. The sensor components of the inflammasome, often proteins of the nucleotide-binding oligomerization domain-like receptor (NLR) family, detect stress, danger stimuli, and pathogen-associated molecular patterns. We report that the eicosanoid 15-deoxy-Δ12,14-prostaglandin J2 (15d-PGJ2) and related cyclopentenone prostaglandins inhibit caspase-1 activation by the NLRP1 and NLRP3 inflammasomes. This inhibition was independent of 15d-PGJ2’s well characterized role as a peroxisome proliferator receptor-γ agonist, its activation of NRF2, or its anti-inflammatory function as an inhibitor of NF-κB. Instead, 15d-PGJ2 prevents the autoproteolytic activation of caspase-1 and the maturation of IL-1β through induction of a cellular state inhibitory to caspase-1 proteolytic function. The eicosanoid does not directly modify or inactivate the caspase-1 enzyme. Rather, inhibition is dependent on de novo protein synthesis. In a mouse peritonitis model of gout, using monosodium urate crystals to activate NLRP3,15d-PGJ2 caused a significant inhibition of cell recruitment and associated IL-1β release. Furthermore, in a murine anthrax infection model, 15d-PGJ2 reversed anthrax lethal toxin-mediated NLRP1-dependent resistance. The findings reported in this work suggest a novel mechanism for the anti-inflammatory properties of the cyclopentenone prostaglandins through inhibition of caspase-1 and the inflammasome. PMID:25681332

  1. Molecular characterization and knock-down of salmon louse (Lepeophtheirus salmonis) prostaglandin E synthase.

    PubMed

    Eichner, Christiane; Øvergård, Aina-Cathrine; Nilsen, Frank; Dalvin, Sussie

    2015-12-01

    The salmon louse (Lepeophtheirus salmonis) is a major parasite of salmonid fish in the marine environment. The interaction between the parasite and the host upon infection is not completely understood. However, it is clear that the parasite influences the host and its immune system. Prostaglandins produced by parasites such as flatworms, roundworms and ticks are documented or assumed to play a role in immunomodulation of the host. In the salmon louse, the effect of prostaglandins on the host is assumed, but remains to be documented. In this study, a salmon louse prostaglandin E2 synthase (LsPGES2) is characterized. Ontogenetic analysis showed that LsPGES2 is relatively stable expressed during development. The highest level of expression was seen in the free living stages, although elevated levels of LsPGES2 were also found in adult females. In copepodids, LsPGES2 is found around muscle cells, while it is observed in the reproductive organs of adult female lice. LsPGES2 expression was knocked-down by RNA interference in nauplii, but emerging copepodids did not display any changes in morphology nor ability to infect and develop to adult stages on fish. Additional knock-down of LsPGES2 in adult female lice did not produce any characteristic changes in phenotype nor reproductive output. It is concluded that under these experimental conditions, knock-down of LsPGES2 did not affect any essential functions of the salmon louse, neither in the free-living nor the parasitic stages. PMID:26348267

  2. Prostaglandin transporter in the rat brain: its localization and induction by lipopolysaccharide

    PubMed Central

    Hosotani, Rika; Inoue, Wataru; Takemiya, Takako; Yamagata, Kanato; Kobayashi, Shigeo; Matsumura, Kiyoshi

    2015-01-01

    Prostaglandin E2 (PGE2) is produced in the brain during infectious/inflammatory diseases, and it mediates acute-phase responses including fever. In the recovery phase of such diseases, PGE2 disappears from the brain through yet unidentified mechanisms. Rat prostaglandin transporter (PGT), which facilitates transmembrane transport of PGE2, might be involved in the clearance of PGE2 from the brain. Here, we examined the cellular localization of PGT mRNA and its protein in the brains of untreated rats and those injected intraperitoneally with a pyrogen lipopolysaccharide (LPS) or saline. PGT mRNA was weakly expressed in the arachnoid membrane of untreated rats and saline-injected ones, but was induced in blood vessels of the subarachnoidal space and choroid plexus and in arachnoid membrane at 5 h and 12 h after LPS injection. In the same type of cells, PGT-like immunoreactivity was found in the cytosol and cell membrane even under nonstimulated conditions, and its level was also elevated after LPS injection. PGT-positive cells in blood vessels were identified as endothelial cells. In most cases, PGT was not colocalized with cyclooxygenase-2, a marker of prostaglandin-producing cells. The PGE2 level in the cerebrospinal fluid reached its peak at 3 h after LPS, and then dropped over 50% by 5 h, which time point coincides with the maximum PGT mRNA expression and enhanced level of PGT protein. These results suggest that PGT is involved in the clearance of PGE2 from the brain during the recovery phase of LPS-induced acute-phase responses. PMID:27227056

  3. Electron microscopic aspects of the effects of certain prostaglandin analogs on mouse testes.

    PubMed

    Sava, Anca; Motoc, Andrei Gheorghe Marius; Stan, Cristinel Ionel

    2015-01-01

    Prostaglandins were highlighted in the seminal plasma and then in the rest of the male and female genital tract. Prostaglandin analogs, firstly used in obstetrics and gynecology, are now widespread in both sexes, especially in the treatment of gastric and duodenal ulcers, glaucoma, etc. Therefore, we tried to highlight the effects of repeated administration of Cloprostenol and CIPG isopropyl ester (both prostaglandin F2α analogs) for the male gonad. In our experiment, we used Cloprostenol and CIPG isopropyl ester. We used three groups of white, male mice, aged 50-80 days, kept in standard laboratory conditions, which received the same feed. Each group included 12 mice. The first batch was the control group and received no substance at all. The second batch received 25 μg/kg of Cloprostenol dose per body per day, intraperitoneal administration (a single dose per day) on a daily basis for a four weeks period of time. The third batch received a 25 μg/kg CIPG isopropyl ester dose per body/day intraperitoneal administration (a single dose per day) on a daily basis for a four weeks period of time. After 7, 14 and 28 days of treatment, we sacrificed four animals in each of the batches by cutting their carotid arteries. The prostanoid analogs we used, Cloprostenol and CIPG isopropyl ester, have similar actions on male gonad in mice. These analogs induced significant changes in the evolution of the spermatogenesis and spermiogenesis. In relation to the treatment duration there were cellular changes suggesting apoptosis in different stages. With regard to spermiogenesis, the ultrastructural aspects indicate a decrease of the sperm structuring processes, especially in the acrosomal apparatus and chromatin. PMID:26429171

  4. Pharmacotherapy of intraocular pressure - part II. Carbonic anhydrase inhibitors, prostaglandin analogues and prostamides.

    PubMed

    Costagliola, Ciro; dell'Omo, Roberto; Romano, Mario R; Rinaldi, Michele; Zeppa, Lucia; Parmeggiani, Francesco

    2009-12-01

    The second part of this two part review (please see Expert Opinion on Pharmacotherapy 10(16)) reports the characteristics of other antiglaucoma medications: systemic (acetazomide) and topical (dorzolamide and brinzolamide) carbonic anhydrase inhibitors, which suppress aqueous humour formation; and prostaglandin analogues (latanoprost and travoprost) and prostamides (bimatoprost), which raise aqueous humour outflow. The pharmacologic properties of each compound and its efficacy in the medical treatment of glaucoma, mainly the primary open-angle form, are discussed briefly, focusing on the clinical evidence supporting their use. PMID:19929706

  5. Prostaglandin E2 Prevents Hyperosmolar-Induced Human Mast Cell Activation through Prostanoid Receptors EP2 and EP4

    PubMed Central

    Torres-Atencio, Ivonne; Ainsua-Enrich, Erola; de Mora, Fernando; Picado, César; Martín, Margarita

    2014-01-01

    Background Mast cells play a critical role in allergic and inflammatory diseases, including exercise-induced bronchoconstriction (EIB) in asthma. The mechanism underlying EIB is probably related to increased airway fluid osmolarity that activates mast cells to the release inflammatory mediators. These mediators then act on bronchial smooth muscle to cause bronchoconstriction. In parallel, protective substances such as prostaglandin E2 (PGE2) are probably also released and could explain the refractory period observed in patients with EIB. Objective This study aimed to evaluate the protective effect of PGE2 on osmotically activated mast cells, as a model of exercise-induced bronchoconstriction. Methods We used LAD2, HMC-1, CD34-positive, and human lung mast cell lines. Cells underwent a mannitol challenge, and the effects of PGE2 and prostanoid receptor (EP) antagonists for EP1–4 were assayed on the activated mast cells. Beta-hexosaminidase release, protein phosphorylation, and calcium mobilization were assessed. Results Mannitol both induced mast cell degranulation and activated phosphatidyl inositide 3-kinase and mitogen-activated protein kinase (MAPK) pathways, thereby causing de novo eicosanoid and cytokine synthesis. The addition of PGE2 significantly reduced mannitol-induced degranulation through EP2 and EP4 receptors, as measured by beta-hexosaminidase release, and consequently calcium influx. Extracellular-signal-regulated kinase 1/2, c-Jun N-terminal kinase, and p38 phosphorylation were diminished when compared with mannitol activation alone. Conclusions Our data show a protective role for the PGE2 receptors EP2 and EP4 following osmotic changes, through the reduction of human mast cell activity caused by calcium influx impairment and MAP kinase inhibition. PMID:25329458

  6. Expression of prostaglandin E2 prostanoid receptor EP2 and interleukin-1β in laryngeal carcinoma – preliminary study

    PubMed Central

    Mochocki, Marcin; Morawski, Piotr; Kopta, Renata; Brzezińska-Błaszczyk, Ewa; Stasikowska, Olga; Lewy-Trenda, Iwona

    2015-01-01

    Aim of the study Expression of EP2 protein, the prostaglandin E2 (PGE2) receptor, produced by tumour microenvironment inflammatory cells as well as tumour cells, may promote cellular proliferation and growth in an autocrine and paracrine fashion. The phenomenon involving these proteins is regulated by interleukin 1β (IL-1β). Many researchers indicate a connection of EP2 and IL-1β in various types of neoplasms with higher tumour progression and poor prognosis. The aim of this study was to analyse the EP2 expression within laryngeal carcinoma tissue and IL-1β levels in peripheral blood mononuclear cell supernatants and to find relationships between clinicomorphological features. Material and methods A group of 50 patients with verified squamous cell laryngeal carcinoma was analysed in this study. The pathological evaluation included pTNM depth of invasion according to tumour front grading criteria. Immunohistochemical analysis for membranous staining of EP2 in tumour tissues was used. The IL-1β expression was determined by enzyme-linked immunosorbent assay (ELISA). Results Increased EP2 expression in carcinoma cells was confirmed for more advanced tumours (pT3-pT4 vs. pT1-pT2, p < 0.0001 and pN1-3 vs. pN0, p = 0.02). Tumours with the highest aggressiveness identified by deeper invasion of submucosa or cartilage were characterised by the highest expression of EP2 (p < 0.0001). In laryngeal carcinomas characterised by a lower differentiation the highest EP2 expression in tumour cells was noted (p = 0.009). A positive relationship between IL-1β expression and the presence of lymph node metastases was also confirmed (p = 0.04). Conclusions The study indicates the potential effect of EP2 receptor and IL-1β on tumour progression in laryngeal carcinoma. PMID:26034388

  7. Definition of Prostaglandin E2-EP2 Signals in the Colon Tumor Microenvironment That Amplify Inflammation and Tumor Growth.

    PubMed

    Ma, Xiaojun; Aoki, Tomohiro; Tsuruyama, Tatsuaki; Narumiya, Shuh

    2015-07-15

    Inflammation in the colon contributes significantly to colorectal cancer development. While aspirin reduces the colorectal cancer risk, its action mechanism, especially in inflammation in tumor microenvironment, still remains obscure. Here, we examined this issue by subjecting mice deficient in each prostaglandin (PG) receptor to colitis-associated cancer model. Deficiency of PGE receptor subtype EP2 selectively reduced, and deficiency of EP1 and EP3 enhanced, the tumor formation. EP2 is expressed in infiltrating neutrophils and tumor-associated fibroblasts in stroma, where it regulates expression of inflammation- and growth-related genes in a self-amplification manner. Notably, expression of cytokines such as TNFα and IL6, a chemokine, CXCL1, a PG-producing enzyme, COX-2, and Wnt5A was significantly elevated in tumor lesions of wild-type mice but this elevation was significantly suppressed in EP2-deficient mice. Intriguingly, EP2 stimulation in cultured neutrophils amplified expression of TNFα, IL6, CXCL1, COX-2, and other proinflammatory genes synergistically with TNFα, and EP2 stimulation in cultured fibroblasts induced expression of EP2 itself, COX-2, IL6, and Wnt genes. EP2 expression in infiltrating neutrophils and tumor-associated fibroblasts was also found in clinical specimen of ulcerative colitis-associated colorectal cancer. Bone marrow transfer experiments suggest that EP2 in both cell populations is critical for tumorigenesis. Finally, administration of a selective EP2 antagonist potently suppressed tumorigenesis in this model. Our study has thus revealed that EP2 in neutrophils and tumor-associated fibroblasts promotes colon tumorigenesis by amplifying inflammation and shaping tumor microenvironment, and suggests that EP2 antagonists are promising candidates of aspirin-alternative for chemoprevention of colorectal cancer. PMID:26018088

  8. Prostaglandin D2 activates group 2 innate lymphoid cells through chemoattractant receptor-homologous molecule expressed on TH2 cells☆

    PubMed Central

    Xue, Luzheng; Salimi, Maryam; Panse, Isabel; Mjösberg, Jenny M.; McKenzie, Andrew N.J.; Spits, Hergen; Klenerman, Paul; Ogg, Graham

    2014-01-01

    Background Activation of the group 2 innate lymphoid cell (ILC2) population leads to production of the classical type 2 cytokines, thus promoting type 2 immunity. Chemoattractant receptor-homologous molecule expressed on TH2 cells (CRTH2), a receptor for prostaglandin D2 (PGD2), is expressed by human ILC2s. However, the function of CRTH2 in these cells is unclear. Objectives We sought to determine the role of PGD2 and CRTH2 in human ILC2s and compare it with that of the established ILC2 activators IL-25 and IL-33. Methods The effects of PGD2, IL-25, and IL-33 on the cell migration, cytokine production, gene regulation, and receptor expression of ILC2s were measured with chemotaxis, ELISA, Luminex, flow cytometry, quantitative RT-PCR, and QuantiGene assays. The effects of PGD2 under physiologic conditions were evaluated by using the supernatant from activated mast cells. Results PGD2 binding to CRTH2 induced ILC2 migration and production of type 2 cytokines and many other cytokines. ILC2 activation through CRTH2 also upregulated the expression of IL-33 and IL-25 receptor subunits (ST2 and IL-17RA). The effects of PGD2 on ILC2s could be mimicked by the supernatant from activated human mast cells and inhibited by a CRTH2 antagonist. Conclusions PGD2 is an important and potent activator of ILC2s through CRTH2 mediating strong proallergic inflammatory responses. Through IgE-mediated mast cell degranulation, these innate cells can also contribute to adaptive type 2 immunity; thus CRTH2 bridges the innate and adaptive pathways in human ILC2s. PMID:24388011

  9. Bromoenol Lactone, an Inhibitor of Calcium-Independent Phospholipase A2, Suppresses Carrageenan-Induced Prostaglandin Production and Hyperalgesia in Rat Hind Paw

    PubMed Central

    Tsuchida, Keiichiro; Ibuki, Takae; Matsumura, Kiyoshi

    2015-01-01

    Prostaglandin (PG) E2 and PGI2 are essential to hyperalgesia in inflammatory tissues. These prostaglandins are produced from arachidonic acid, which is cleaved from membrane phospholipids by the action of phospholipase A2 (PLA2). Which isozyme of PLA2 is responsible for the cleavage of arachidonic acid and the production of prostaglandins essential to inflammation-induced hyperalgesia is not clear. In this study, we examined the effects of two PLA2 isozyme-specific inhibitors on carrageenan-induced production of PGE2 and PGI2 in rat hind paw and behavioral nociceptive response to radiant heat. Local administration of bromoenol lactone (BEL), an inhibitor of calcium-independent PLA2 (iPLA2), significantly reduced carrageenan-induced elevation of prostaglandins in the inflamed foot pad 3 h after injection. It also ameliorated the hyperalgesic response between 1 h and 3 h after carrageenan injection. On the other hand, AACOCF3, an inhibitor of cytosolic PLA2, suppressed neither prostaglandin production nor the hyperalgesic response. BEL did not suppress the mRNA levels of iPLA2β, iPLA2γ, cyclooxygenase-2, microsomal prostaglandin E synthase, prostaglandin I synthase, or proinflammatory cytokines in the inflamed foot pad, indicating that BEL did not suppress inflammation itself. These results suggest that iPLA2 is involved in the production of prostaglandins and hyperalgesia at the inflammatory loci. PMID:26063975

  10. Quantitative phosphoproteomic analysis of signaling downstream of the prostaglandin e2/g-protein coupled receptor in human synovial fibroblasts: potential antifibrotic networks.

    PubMed

    Gerarduzzi, Casimiro; He, QingWen; Antoniou, John; Di Battista, John A

    2014-11-01

    The Prostaglandin E2 (PGE2) signaling mechanism within fibroblasts is of growing interest as it has been shown to prevent numerous fibrotic features of fibroblast activation with limited evidence of downstream pathways. To understand the mechanisms of fibroblasts producing tremendous amounts of PGE2 with autocrine effects, we apply a strategy of combining a wide-screening of PGE2-induced kinases with quantitative phosphoproteomics. Our large-scale proteomic approach identified a PKA signal transmitted through phosphorylation of its substrates harboring the R(R/X)X(S*/T*) motif. We documented 115 substrates, of which 72 had 89 sites with a 2.5-fold phosphorylation difference in PGE2-treated cells than in untreated cells, where approximately half of such sites were defined as being novel. They were compiled by networking software to focus on highlighted activities and to associate them with a functional readout of fibroblasts. The substrates were associated with a variety of cellular functions including cytoskeletal structures (migration/motility), regulators of G-protein coupled receptor function, protein kinases, and transcriptional/translational regulators. For the first time, we extended the PGE2 pathway into an elaborate network of interconnecting phosphoproteins, providing vital information to a once restricted signalosome. These data provide new insights into eicosanoid-initiated cell signaling with regards to the regulation of fibroblast activation and the identification of new targets for evidenced-based pharmacotherapy against fibrosis. PMID:25223752

  11. Cyclooxygenase-2 prostaglandins mediate anandamide-inhibitory action on nitric oxide synthase activity in the receptive rat uterus.

    PubMed

    Sordelli, Micaela S; Beltrame, Jimena S; Cella, Maximiliano; Franchi, Ana M; Ribeiro, Maria Laura

    2012-06-15

    Anandamide, an endocannabinoid, prostaglandins derived from cyclooxygenase-2 and nitric oxide synthesized by nitric oxide synthase (NOS), are relevant mediators of embryo implantation. We adopted a pharmacological approach to investigate if anandamide modulated NOS activity in the receptive rat uterus and if prostaglandins mediated this effect. As we were interested in studying the changes that occur at the maternal side of the fetal-maternal interface, we worked with uteri obtained from pseudopregnant rats. Females were sacrificed on day 5 of pseudopregnancy, the day in which implantation would occur, and the uterus was obtained. Anandamide (2 ng/kg, i.p.) inhibited NOS activity (P<0.001) and increased the levels of prostaglandin E(2) (P<0.001) and prostaglandin F(2α) (P<0.01). These effects were mediated via cannabinoid receptor type 2, as the pre-treatment with SR144528 (10 mg/kg, i.p.), a selective cannabinoid receptor type 2 antagonist, completely reverted anandamide effect on NOS activity and prostaglandin levels. The pre-treatment with a non-selective cyclooxygenase inhibitor (indomethacin 2.5mg/kg, i.p.) or with selective cyclooxygenase-2 inhibitors (meloxicam 4 mg/kg, celecoxib 3mg/kg, i.p.) reverted anandamide inhibition on NOS, suggesting that prostaglandins are derived from cyclooxygenase-2 mediated anandamide effect. Thus, anandamide levels seemed to modulate NOS activity, fundamental for implantation, via cannabinoid receptor type 2 receptors, in the receptive uterus. This modulation depends on the production of cyclooxygenase-2 derivatives. These data establish cannabinoid receptors and cyclooxygenase enzymes as an interesting target for the treatment of implantation deficiencies. PMID:22554772

  12. Progesterone receptor expression declines in the guinea pig uterus during functional progesterone withdrawal and in response to prostaglandins.

    PubMed

    Welsh, Toni N; Hirst, Jonathan J; Palliser, Hannah; Zakar, Tamas

    2014-01-01

    Progesterone withdrawal is essential for parturition, but the mechanism of this pivotal hormonal change is unclear in women and other mammals that give birth without a pre-labor drop in maternal progesterone levels. One possibility suggested by uterine tissue analyses and cell culture models is that progesterone receptor levels change at term decreasing the progesterone responsiveness of the myometrium, which causes progesterone withdrawal at the functional level and results in estrogen dominance enhancing uterine contractility. In this investigation we have explored whether receptor mediated functional progesterone withdrawal occurs during late pregnancy and labor in vivo. We have also determined whether prostaglandins that induce labor cause functional progesterone withdrawal by altering myometrial progesterone receptor expression. Pregnant guinea pigs were used, since this animal loses progesterone responsiveness at term and gives birth in the presence of high maternal progesterone level similarly to primates. We found that progesterone receptor mRNA and protein A and B expression decreased in the guinea pig uterus during the last third of gestation and in labor. Prostaglandin administration reduced while prostaglandin synthesis inhibitor treatment increased progesterone receptor A protein abundance. Estrogen receptor-1 protein levels remained unchanged during late gestation, in labor and after prostaglandin or prostaglandin synthesis inhibitor administration. Steroid receptor levels were higher in the non-pregnant than in the pregnant uterine horns. We conclude that the decreasing expression of both progesterone receptors A and B is a physiological mechanism of functional progesterone withdrawal in the guinea pig during late pregnancy and in labor. Further, prostaglandins administered exogenously or produced endogenously stimulate labor in part by suppressing uterine progesterone receptor A expression, which may cause functional progesterone withdrawal, promote

  13. The Effect of Thyroid Hormone, Prostaglandin E2, and Calcium Gluconate on Orthodontic Tooth Movement and Root Resorption in Rats

    PubMed Central

    Seifi, Massoud; Hamedi, Roya; Khavandegar, Zohre

    2015-01-01

    Statement of the Problem A major objective of investigators is to clarify the role of metabolites in achievement of maximum tooth movement with minimal root damage during orthodontic tooth movement (OTM). Purpose The aim of this study was to determine the effect of administration of thyroid hormone, prostaglandin E2, and calcium on orthodontic tooth movement and root resorption in rats. Materials and Method Sixty four male Wistar rats were randomly divided into 8 groups