Periapical bone response to bacterial lipopolysaccharide is shifted upon cyclooxygenase blockage

Abstract Objectives: Infection, inflammation and bone resorption are closely related events in apical periodontitis development. Therefore, we sought to investigate the role of cyclooxygenase (COX) in osteoclastogenesis and bone metabolism signaling in periapical bone tissue after bacterial lipopolysaccharide (LPS) inoculation into root canals. Methodology: Seventy two C57BL/6 mice had the root canals of the first molars inoculated with a solution containing LPS from E. coli (1.0 mg/mL) and received selective (celecoxib) or non-selective (indomethacin) COX-2 inhibitor. After 7, 14, 21 and 28 days the animals were euthanized and the tissues removed for total RNA extraction. Evaluation of gene expression was performed by qRT-PCR. Statistical analysis was performed using analysis of variance (ANOVA) followed by post-tests (α=0.05). Results: LPS induced expression of mRNA for COX-2 (Ptgs2) and PGE2 receptors (Ptger1, Ptger3 and Ptger4), indicating that cyclooxygenase is involved in periapical response to LPS. A signaling that favours bone resorption was observed because Tnfsf11 (RANKL), Vegfa, Ctsk, Mmp9, Cd36, Icam, Vcam1, Nfkb1 and Sox9 were upregulated in response to LPS. Indomethacin and celecoxib differentially modulated expression of osteoclastogenic and other bone metabolism genes: celecoxib downregulated Igf1r, Ctsk, Mmp9, Cd36, Icam1, Nfkb1, Smad3, Sox9, Csf3, Vcam1 and Itga3 whereas indomethacin inhibited Tgfbr1, Igf1r, Ctsk, Mmp9, Sox9, Cd36 and Icam1. Conclusions: We demonstrated that gene expression for COX-2 and PGE2 receptors was upregulated after LPS inoculation into the root canals. Additionally, early administration of indomethacin and celecoxib (NSAIDs) inhibited osteoclastogenic signaling. The relevance of the cyclooxygenase pathway in apical periodontitis was shown by a wide modulation in the expression of genes involved in both bone catabolism and anabolism.

Prostaglandin E receptors differentially regulate the output of proinflammatory cytokines in myometrial cells from term pregnant women / 生理学报

Prostaglandin (PG) E plays critical roles during pregnancy and parturition. Emerging evidence indicates that human labour is an inflammatory event. We sought to investigate the effect of PGE on the output of proinflammatory cytokines in cultured human uterine smooth muscle cells (HUSMCs) from term pregnant women and elucidate the role of subtypes of PGE receptors (EP, EP, EP and EP). After drug treatment and/or transfection of each receptor siRNA, the concentrations of inflammatory secreting factors in HUSMCs culture medium were detected by the corresponding ELISA kits. The results showed that, PGE increased interleukin 6 (IL-6) and tumor necrosis factor alpha (TNFα) output, decreased chemokine (c-x-c motif) ligand 8 (CXCL8) output in a dose-dependent manner, but had no effect on IL-1β and chemokine (c-c motif) ligand 2 (CCL-2) secretion of HUSMCs. EP/EP agonist 17-phenyl-trinor-PGE stimulated IL-6 and TNFα whilst suppressing IL-1β and CXCL8 output. The effects of 17-phenyl-trinor-PGE on IL-1β and CXCL8 secretion were remained whereas its effect on IL-6 and TNFα output did not occur in the cells with EP knockdown. The stimulatory effects of 17-phenyl-trinor-PGE on IL-6 and TNFα were remained whereas the inhibitory effects of 17-phenyl-trinor-PGE on IL-1β secretion was blocked in the cells with EP knockdown. Either of EP and EP agonists stimulated IL-1β and TNFα output, which was reversed by EP and EP siRNA, respectively. The inhibitors of phospholipase C (PLC) and protein kinase C (PKC) blocked EP/EP modulation of TNFα and CXCL8 output. PI3K inhibitor LY294002 and P38 inhibitor SB202190 blocked 17-phenyl-trinor-PGE-induced IL-1β and IL-6 output, respectively. The inhibitors of adenylyl cyclase and PKA prevented EP and EP stimulation of IL-1β and TNFα output, whereas PLC and PKC inhibitors blocked EP- and EP-induced TNFα output but not IL-1β output. Our data suggest that PGE receptors exhibit different effects on the output of various cytokines in myometrium, which can subtly modulate the inflammatory microenvironment in myometrium during pregnancy.

Blockade of PGE2, PGD2 receptors confers protection against prepatent Schistosomiasis Mansoni in mice

Schistosomiasis is a chronic disease with considerable social impact. Despite the availability of affordable chemotherapy, drug treatment has not significantly reduced the overall number of disease cases. Among other mechanisms, the parasite produces PGE2 and PGD2 to evade host immune defenses. To investigate the role of PGE2 and PGD2 in schistosomiasis, we evaluated the effects of L-161,982, Ah6809 [PGE2 receptor antagonists alone or combined with each other] and MK-0524 [PGD2 receptor antagonist] during prepatent Schistosoma mansoni infection. Drugs were administered intraperitoneally an hour before and 24 hours after infection of C57BL/6 mice with 100 Schistosoma mansoni cercariae. L-161,982, Ah6809, their combination and MK-0524 caused partial protection against pre-patent S. mansoni infection which was mediated by biasing the immune response towards Th1 phenotype. These results showed that blockade of PGE2 and PGD2 receptors confers partial protection against pre-patent S. mansoni infection in mice and that they may be useful as adjunctive therapy to current anti-schistosomal drugs or vaccines

Lubiprostone Increases Small Intestinal Smooth Muscle Contractions Through a Prostaglandin E Receptor 1 (EP1)-mediated Pathway

BACKGROUND/AIMS: Lubiprostone, a chloride channel type 2 (ClC-2) activator, was thought to treat constipation by enhancing intestinal secretion. It has been associated with increased intestinal transit and delayed gastric emptying. Structurally similar to prostones with up to 54% prostaglandin E2 activity on prostaglandin E receptor 1 (EP1), lubiprostone may also exert EP1-mediated procontractile effect on intestinal smooth muscles. We investigated lubiprostone's effects on intestinal smooth muscle contractions and pyloric sphincter tone. METHODS: Isolated murine small intestinal (longitudinal and circular) and pyloric tissues were mounted in organ baths with modified Krebs solution for isometric recording. Basal muscle tension and response to electrical field stimulation (EFS; 2 ms pulses/10 V/6 Hz/30 sec train) were measured with lubiprostone (10(-10)-10(-5) M) +/- EP1 antagonist. Significance was established using Student t test and P < 0.05. RESULTS: Lubiprostone had no effect on the basal tension or EFS-induced contractions of longitudinal muscles. With circular muscles, lubiprostone caused a dose-dependent increase in EFS-induced contractions (2.11 +/- 0.88 to 4.43 +/- 1.38 N/g, P = 0.020) that was inhibited by pretreatment with EP1 antagonist (1.69 +/- 0.70 vs. 4.43 +/- 1.38 N/g, P = 0.030). Lubiprostone had no effect on circular muscle basal tension, but it induced a dose-dependent increase in pyloric basal tone (1.07 +/- 0.01 to 1.97 +/- 0.86 fold increase, P < 0.05) that was inhibited by EP1 antagonist. CONCLUSIONS: In mice, lubiprostone caused a dose-dependent and EP1-mediated increase in contractility of circular but not longitudinal small intestinal smooth muscles, and in basal tone of the pylorus. These findings suggest another mechanism for lubiprostone's observed clinical effects on gastrointestinal motility.

Prostaglandin E2 Receptors on Upper Respiratory Tract / 대한이비인후과학회지

Prostaglandin (PG) E2 exerts its actions by acting on a group of G-protein-coupled receptors (GPCRs). GPCRs responding to PGE2 consist of four subtypes namely E-prostanoid 1 (EP1), E-prostanoid 2 (EP2), E-prostanoid 3 (EP3), and E-prostanoid 4 (EP4) and multiple splicing isoforms of the subtype EP3. The EP subtypes exhibit differences in signal transduction pathway, tissue localization, and regulation of expression. This molecular and biochemical heterogeneity of PGE2 receptors leads to PGE2 being the most variable prostanoid. Studies on knockout mice deficient in each EP subtype and selective agonist and antagonist have defined PGE2 actions mediated by each subtype and identified the role each EP subtype plays in various physiological and pathophysiological responses. We summarize and review PGE2 receptor research.

Roles of cyclooxygenase-2 in microvascular endothelial cell proliferation induced by basic fibroblast growth factor / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The level of basic fibroblast growth factor (bFGF) increases rapidly after cerebral ischemia. However, the molecular mechanisms for the effects of bFGF on cerebral microvascular endothelial cells (cMVECs) have not yet been fully elucidated. In this study, a murine cMVEC line, bEnd.3, was employed to study the effects of bFGF on cyclooxygenase (COX) expression and its downstream effects in cMVECs.</p><p><b>METHODS</b>After treatment with bFGF, RT-PCR and Western blotting analyses were carried out to evaluate the changes in COX-2 mRNA and protein expression, respectively. MTT assays were performed to measure cell proliferation. The prostaglandin E2 (PGE2) and vascular endothelial growth factor (VEGF) concentrations in the culture medium were measured by enzyme-linked immunosorbent assay (ELISA).</p><p><b>RESULTS</b>COX-2 mRNA and protein expressions in bEnd.3 cells were induced by bFGF in time- and dose-dependent manners. The bFGF-induced COX-2 upregulation led to enhanced PGE2 production by bEnd.3 cells, and this effect was abolished by the selective COX-2 inhibitor NS-398. bFGF also increased VEGF production by bEnd.3 cells, and this effect was blocked by NS-398 and the EP1/2 (PGE2 receptors) antagonist AH6809. Furthermore, exogenous PGE2 increased VEGF production in bEnd.3 cells, and AH6809 blocked this effect.</p><p><b>CONCLUSION</b>bFGF increases VEGF production in an autocrine manner by increasing COX-2-generated PGE2 in cMVECs and subsequently stimulates MVEC proliferation and angiogenesis.</p>

Lysophosphatidic acid receptor 2 and Gi/Src pathway mediate cell motility through cyclooxygenase 2 expression in CAOV-3 ovarian cancer cells

Lysophosphatidic acid (LPA) is a bioactive phospholipids and involves in various cellular events, including tumor cell migration. In the present study, we investigated LPA receptor and its transactivation to EGFR for cyclooxygenase-2 (COX-2) expression and cell migration in CAOV-3 ovarian cancer cells. LPA induced COX-2 expression in a dose-dependent manner, and pretreatment of the cells with pharmacological inhibitors of Gi (pertussis toxin), Src (PP2), EGF receptor (EGFR) (AG1478), ERK (PD98059) significantly inhibited LPA- induced COX-2 expression. Consistent to these results, transfection of the cells with selective Src siRNA attenuated COX-2 expression by LPA. LPA stimulated CAOV-3 cell migration that was abrogated by pharmacological inhibitors and antibody of EP2. Higher expression of LPA2 mRNA was observed in CAOV-3 cells, and transfection of the cells with a selective LPA2 siRNA significantly inhibited LPA-induced activation of EGFR and ERK, as well as COX-2 expression. Importantly, LPA2 siRNA also blocked LPA-induced ovarian cancer cell migration. Collectively, our results clearly show the significance of LPA2 and Gi/Src pathway for LPA-induced COX-2 expression and cell migration that could be a promising drug target for ovarian cancer cell metastasis.

Effect of guizhi decoction on PKA and PKC activities of hypothalamus in fever rats / 中国中药杂志

<p><b>OBJECTIVE</b>To investigate the changes of the activity of both protein kinase A and C and the mechanisms of antipyretic action of Guizhi decoction.</p><p><b>METHOD</b>The fever responses were observed after combination injection of H-89 (a selective inhibitor of PKA) and calphostin C (a selective inhibitor of PKC), and oral pretreatment of Guizhi decoction in fever rats induced by an intra-cerebroventricular (icv) injection of an EP3 agonist, and both PKA and PKC activity in hypothalamus were measured in rats pretreated with Guizhi decoction and vehicle using isotopic tracing assay.</p><p><b>RESULT</b>The rise in rat body temperature was inhibited by H-89, Calphostin C, and Guizhi decoction, moreover, pretreatment with Guizhi decoction reduced PKA activity obviously. PKC activity in model rats exhibited a tendency to drop compared with that of control group, Oral administration of Guizhi decoction in large dose inhibited the response significantly, while the low dose of Guzhi decoction has no effect on PKC.</p><p><b>CONCLUSION</b>Both PKA and PKC may participate in the mechanism of fever induction by EP3 agonist. The decrease of PKA and PKC may contribute to the antipyretic action of Guizhi decoction, some isoenzyme of PKC may play a role in the fever production.</p>

The Effects of Selective Cyclooxygenase-2 Inhibitor and Prostaglandin E2 Receptor Agonists on the Endothelin Axis of Prostate Cancer Cells / 대한비뇨기과학회지

PURPOSE: The enhanced expression of the cyclooxygenase-2 (COX-2), prostaglandin E2 receptor (EPs) and endothelin-1 (ET-1) axis is known to play a significant role in the development and progression of several malignancies. To date, little work has been done to investigate the relationships between the COX-2, EPs and ET-1 axis in prostate cancer (PC) cells. The aim of this study is to investigate the expression of preproET-1 (PPET-1), ET-1 receptor A (ET(A)R), and endothelin converting enzyme-1 (ECE-1) in the PC cell lines and to evaluate the effects of COX-2 and EPs on the expression of PPET-1, ET(A)R, and ECE-1. MATERIALS AND METHODS: Two PC cell lines, PC-3 and DU-145 cells were used for this study. By performing reverse transcription polymerase chain reaction (RT-PCR), the mRNA expressions of PPET-1, ET(A)R and ECE-1 were detected, and then the mRNA expressions of PPET-1, ET(A)R and ECE-1 were detected after being treating the cells with selective COX-2 inhibitor (NS-398), or EP2 (butaprost) and EP4 (misoprostol), which are both agonist of 10(-10), 10(-8) and 10(-6)M. RESULTS: PPET-1, ET(A)R and ECE-1 mRNA were expressed in both cell lines. After NS-398 treatment, only the PPET-1 mRNA expression was decreased at 4, 8 and 12 hours in the PC-3 cells. EP2 and EP4 agonist induced an increase for the PPET-1, ET(A)R and ECE-1 mRNA expressions, compared with the NS-398 treated group (control), in the PC-3 cells. CONCLUSIONS: ET-1/ET(A)R and ECE-1, whose expressions are increased by EP2 and EP4, may play key roles in the development and progression of PC via COX-2. A combination treatment with selective inhibitors for COX-2, EPs and ET(A)R would be novel approach to prostate cancer therapy.

Prostagladin E Receptor II and IV Increase the Expression of Martrix Metalloproteinase-7 in PC (Prostate Cancer)-3 Cells / 대한비뇨기과학회지

PURPOSE: The effects of PGE2 receptors (EP1, 2, 3, 4) on the proliferation of prostate cancer cells are still unclear. The degradation of the basement membrane by MMP-2, 7, 9 and TIMP-1, 2 is a critical point in tumor invasion and metastasis. We investigated the effects of PGE2 receptors concerning MMP and TIMP after the treatment of COX-2 inhibitors on prostate cancer cell-lines. MATERIALS AND METHODS: Two prostate cancer cell-lines, PC-3 and DU-145 cells were used in this study. RT-PCR were performed to detect the mRNA expression of EP1, 2, 3, 4, MMP-2, 7, 9 and TIMP-1, 2, MMP-7 was measured by ELISA after being treated with the selective EP2 agonist and EP4 agonist 10(-10), 10(-8), 10(-6) microM respectively. RESULTS: EP2, 3 and 4 mRNA were expressed in both cell-lines. After the NS-398 treatment, EP2 and EP4 mRNA expressions decreased in PC-3 cells. While only the MMP-7 mRNA expression decreased in PC-3 cells after NS-398 treatment, after NS-398 with selective EP2 agonist and EP4 agonist, MMP-7 mRNA expression increased. In PC-3 cells, selective EP2 agonist and EP4 agonist induced a significant dose-dependent increase in MMP-7 production in comparison to the NS-398 treatment group (control) in the conditioned ELISA medium. CONCLUSIONS: These results strongly suggest that COX-2, to some extent, contribute to prostate carcinogenesis at the EP2 and EP4 receptor, which could also be explained by increments of MMP-7 in PC-3 cells. Therefore, these findings show that selective EP inhibitor is useful in preventing specific disease progression in prostate cancer.

The Prostaglandin E Receptor Agonists Increase Granulocyte Macrophage Colony-Stimulating Factor in Prostate Cancer Cells / 대한비뇨기과학회지

PURPOSE: The predilection for prostate carcinoma cells to metastasize to bone suggests the hypothesis that bone and/or bone marrow-derived factors may promote prostate carcinoma cell growth and/or their survival. To date, little work has been performed to characterize the nature of granulocyte macrophage colony-stimulating factor (GM-CSF) and the expression of prostaglandin E2 receptors (EPs) in prostate cancer (PC) cells. The aim of this study is to evaluate the effects of GM-CSF on cell proliferation and the effects of EP agonists on the production of GM-CSF in the PC-3 cells. MATERIALS AND METHODS: The bone-derived PC-3 cell line was used in this study. Reverse transcription polymerase chain reaction (RT-PCR) was performed to detect the mRNA expression of EP1, 2, 3 and 4 and hGM- CSF. 3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyltetrazolium bromide (MTT) assay was done to estimate the viability of PC-3 cells after hGM-CSF treatment. hGM-CSF was measured by enzyme-linked immunosorbent assay (ELISA) after treatments with the EPs agonist at 10(-10), 10(-8), 10(-6)M, respectively. RESULTS: EP2, 3 and 4 and hGM-CSF were expressed in the PC-3 cell line. Viability of the PC-3 cells was significantly increased by hGM-CSF administration in a dose- and time-dependent manner. Also, our data indicated that EP2, 3 and especially 4 agonists induced a significant dose- dependent increase in hGM-CSF production in comparison to the control group in the conditioned ELISA medium. CONCLUSIONS: These results suggest that GM-CSF may be part of a network of an autocrine-regulatory loop system that modulates the biologic activity of prostate carcinoma cells. Our data suggest that GM-CSF and EPs may represent a possible novel therapeutic target that manipulates the proliferative rate of prostate tumors.

The Prostaglandin E Receptor Agonists Increase Granulocyte Macrophage Colony-Stimulating Factor in Prostate Cancer Cells / 대한비뇨기과학회지

PURPOSE: The predilection for prostate carcinoma cells to metastasize to bone suggests the hypothesis that bone and/or bone marrow-derived factors may promote prostate carcinoma cell growth and/or their survival. To date, little work has been performed to characterize the nature of granulocyte macrophage colony-stimulating factor (GM-CSF) and the expression of prostaglandin E2 receptors (EPs) in prostate cancer (PC) cells. The aim of this study is to evaluate the effects of GM-CSF on cell proliferation and the effects of EP agonists on the production of GM-CSF in the PC-3 cells. MATERIALS AND METHODS: The bone-derived PC-3 cell line was used in this study. Reverse transcription polymerase chain reaction (RT-PCR) was performed to detect the mRNA expression of EP1, 2, 3 and 4 and hGM- CSF. 3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyltetrazolium bromide (MTT) assay was done to estimate the viability of PC-3 cells after hGM-CSF treatment. hGM-CSF was measured by enzyme-linked immunosorbent assay (ELISA) after treatments with the EPs agonist at 10(-10), 10(-8), 10(-6)M, respectively. RESULTS: EP2, 3 and 4 and hGM-CSF were expressed in the PC-3 cell line. Viability of the PC-3 cells was significantly increased by hGM-CSF administration in a dose- and time-dependent manner. Also, our data indicated that EP2, 3 and especially 4 agonists induced a significant dose- dependent increase in hGM-CSF production in comparison to the control group in the conditioned ELISA medium. CONCLUSIONS: These results suggest that GM-CSF may be part of a network of an autocrine-regulatory loop system that modulates the biologic activity of prostate carcinoma cells. Our data suggest that GM-CSF and EPs may represent a possible novel therapeutic target that manipulates the proliferative rate of prostate tumors.

Effect of guizhi tang and its active components on the fever induced by EP3 agonist / 中国中药杂志

<p><b>OBJECTIVE</b>To investigate the effect of Guizhi Tang and its active components on the fever induced by EP3 receptor agonist sulprostone in rats.</p><p><b>METHOD</b>The rise in body temperature evoked by a LCV(lateral cerebroventricle)-injection of sulprostone was compared with that of sulprostone induced-fever rats pretreated with Guizgi Tang and its active compounds, cinnamaldehyde, cinnamic acid and total glucosides of paeony.</p><p><b>RESULT</b>Pretreatments with Guizhi Tang and cinnamaldehyde inhibited the rise in body temperature induced by sulprostone, while cinnamic acid tended to augment the fever. The sulprostone-induced fever was blocked by an ip pretreatment of total glucosides of paeony even below the basement.</p><p><b>CONCLUSION</b>Present data suggest that interruption with the down-stream events of EP3 receptor may contribute to the antipyretic action of Guizhi Tang, cinnamaldehyde and the total glucosides of paeony, while cinnamic acid may have no such effect.</p>

Detection of EP1 and FP receptor mRNAs in the iris-ciliary body using in situ hybridization / 中华医学杂志(英文版)

<p><b>OBJECTIVE</b>To determine the expression of E-prostanoid1 (EP(1)) and F-prostanoid (FP) receptor mRNAs in iris-ciliary bodies of the human eye using in situ hybridization.</p><p><b>METHODS</b>EP(1) and FP receptor mRNAs were detected by riboprobes labeled with digoxigenin on paraffin sections of the iris-ciliary body tissue of the human eye using in situ hybridization.</p><p><b>RESULTS</b>EP(1) and FP receptor mRNAs were highly expressed in blood vessels, muscles and the endothelia of the iris. EP(1) receptor hybridization signals were present in all muscle fibers of the ciliary body. Hybridization signal corresponding to FP receptor mRNA transcript was predominantly expressed in the circular muscle and in the collagenous connective tissues of the ciliary body. FP receptor mRNA was not detected in radial and longitudinal muscles.</p><p><b>CONCLUSIONS</b>EP(1) and FP receptor mRNAs in human ocular tissues appear to be widely localized in the functional sites of the respective receptor agonists. Selective localization of EP(1) and FP receptor mRNAs in the circular muscles and collagenous connective tissues of the ciliary body suggests that EP(1) and FP receptors play an important role in enhancing uveoscleral outflow of aqueous humor.</p>

Valor predictivo del ecodoppler color peneano con inyección de droga vasoactiva en pacientes con disfunción eréctil / Penile color Doppler US predictive value after vasoactive drug injection in patients with erectile disfunction

A fin de demostrar la utilidad del eco Doppler con drogas vasoactivas para definir la terapéutica en pacientes con disfunción eréctil se estudiaron 54 pacientes con tumescencia nocturna insuficiente, a quienes se les realizó ecografía peneana y Doppler color de las materias cavernosas en condiciones basales y con inyección intracavernosa de 1 cm3 de Trimix, registrándose las velocidades sistólicas basales y postinyección temprana, tardía y postestímulo y evaluando las velocidades sistólicas, distólicas y los índices de resistencia. Los estudios permitieron clasificar a los pacientes en 5 grupos de acuerdo a la etiología de la disfunción y de ese modo brindarles la terapéutica adecuada