Key role for constitutive cyclooxygenase-2 of MDCK cells in basal signaling and response to released ATP

2001 ◽  
Vol 281 (2) ◽  
pp. C524-C531 ◽  
Author(s):  
Rennolds S. Ostrom ◽  
Caroline Gregorian ◽  
Ryan M. Drenan ◽  
Kathryn Gabot ◽  
Brinda K. Rana ◽  
...  
Keyword(s):  
Cell Function ◽  
Mdck Cells ◽  
Second Messengers ◽  
Atp Release ◽  
Cox Inhibitors ◽  
Cox 2 ◽  
Factor Α ◽  
Biochemical Activation ◽  
Camp Formation ◽  
Cox 1

Madin-Darby canine kidney (MDCK) cells release ATP upon mechanical or biochemical activation, initiating P2Y receptor signaling that regulates basal levels of multiple second messengers, including cAMP ( J Biol Chem 275: 11735–11739, 2000). Data shown here document inhibition of cAMP formation by Gd3+ and niflumic acid, channel inhibitors that block ATP release. cAMP production is stimulated via Ca2+-dependent activation of cytosolic phospholipase A2, release of arachidonic acid (AA), and cyclooxygenase (COX)-dependent production of prostaglandins, which activate prostanoid receptors coupled to Gs and adenylyl cyclase. In the current investigation, we assessed the expression and functional role of the two known isoforms of COX, COX-1 and COX-2. Treatment of cells with either a COX-1-selective inhibitor, SC-560, or COX-2-selective inhibitors, SC-58125 or NS-398, inhibited basal and UTP-stimulated cAMP levels. COX inhibitors also decreased forskolin-stimulated cAMP formation, implying this response is in part attributable to an action of AA metabolites. These findings imply an important role for the inducible form of COX, COX-2, under basal conditions. Indeed, COX-2 expression was readily detectable by immunoblot, and treatments that induce or reduce COX-2 expression in other cells (interleukin-1β, tumor necrosis factor-α, phorbol ester, or dexamethasone) had minimal or no effect on the levels of COX-2 immunoreactivity. RT-PCR using isoform-specific primers detected COX-2 mRNA. We conclude that COX-2 is constitutively expressed in MDCK-D1 cells and participates in basal and P2Y2-mediated signaling, implying a key role for COX-2 in regulation of epithelial cell function.

scholarly journals Compensatory Prostaglandin E2 Biosynthesis in Cyclooxygenase 1 or 2 Null Cells

1998 ◽  
Vol 187 (4) ◽  
pp. 517-523 ◽  
Author(s):  
Kanyawim Kirtikara ◽  
Scott G. Morham ◽  
Rajendra Raghow ◽  
Stanley J. F. Laulederkind ◽  
Takuro Kanekura ◽  
...  
Keyword(s):  
Prostaglandin E2 ◽  
Wild Type ◽  
Acidic Fibroblast Growth Factor ◽  
Cox Inhibitors ◽  
Cyclooxygenase 1 ◽  
Enhanced Expression ◽  
Key Enzyme ◽  
Cox 2 ◽  
Factor Α ◽  
Cox 1

Prostaglandin E2 (PGE2) production in immortalized, nontransformed cells derived from wild-type, cyclooxygenase 1–deficient (COX-1−/−) or cyclooxygenase 2–deficient (COX-2−/−) mice was examined after treatment with interleukin (IL)-1β, tumor necrosis factor α, acidic fibroblast growth factor, and phorbol ester (phorbol myristate acetate). Compared with their wild-type counterparts, COX-1−/− or COX-2−/− cells exhibited substantially enhanced expression of the remaining functional COX gene. Furthermore, both basal and IL-1–induced expression of cytosolic phospholipase A2 (cPLA2), a key enzyme-regulating substrate mobilization for PGE2 biosynthesis, was also more pronounced in both COX-1−/− and COX-2−/− cells. Thus, COX-1−/− and COX-2−/− cells have the ability to coordinate the upregulation of the alternate COX isozyme as well as cPLA2 genes to overcome defects in prostaglandin biosynthetic machinery. The potential for cells to alter and thereby compensate for defects in the expression of specific genes such as COX has significant clinical implications given the central role of COX in a variety of disease processes and the widespread use of COX inhibitors as therapeutic agents.

scholarly journals Cyclooxygenases Inhibitors Efficiently Induce Cardiomyogenesis in Human Pluripotent Stem Cells

Cells ◽  
2020 ◽  
Vol 9 (3) ◽  
pp. 554 ◽  
Author(s):  
Harshal Nemade ◽  
Aviseka Acharya ◽  
Umesh Chaudhari ◽  
Erastus Nembo ◽  
Filomain Nguemo ◽  
...  
Keyword(s):  
Wnt Signaling Pathway ◽  
Calcium Transient ◽  
Cardiac Differentiation ◽  
Cyclooxygenase Inhibitors ◽  
Cox Inhibitors ◽  
Screening Model ◽  
Cox 2 ◽  
Transient Measurements ◽  
Cox 1

Application of human pluripotent stem cell-derived cardiomyocytes (hPSC-CMs) is limited by the challenges in their efficient differentiation. Recently, the Wingless (Wnt) signaling pathway has emerged as the key regulator of cardiomyogenesis. In this study, we evaluated the effects of cyclooxygenase inhibitors on cardiac differentiation of hPSCs. Cardiac differentiation was performed by adherent monolayer based method using 4 hPSC lines (HES3, H9, IMR90, and ES4SKIN). The efficiency of cardiac differentiation was evaluated by flow cytometry and RT-qPCR. Generated hPSC-CMs were characterised using immunocytochemistry, electrophysiology, electron microscopy, and calcium transient measurements. Our data show that the COX inhibitors Sulindac and Diclofenac in combination with CHIR99021 (GSK-3 inhibitor) efficiently induce cardiac differentiation of hPSCs. In addition, inhibition of COX using siRNAs targeted towards COX-1 and/or COX-2 showed that inhibition of COX-2 alone or COX-1 and COX-2 in combination induce cardiomyogenesis in hPSCs within 12 days. Using IMR90-Wnt reporter line, we showed that inhibition of COX-2 led to downregulation of Wnt signalling activity in hPSCs. In conclusion, this study demonstrates that COX inhibition efficiently induced cardiogenesis via modulation of COX and Wnt pathway and the generated cardiomyocytes express cardiac-specific structural markers as well as exhibit typical calcium transients and action potentials. These cardiomyocytes also responded to cardiotoxicants and can be relevant as an in vitro cardiotoxicity screening model.

scholarly journals Comparative Analysis of Pharmacologic and/or Genetic Disruption of Cyclooxygenase-1 and Cyclooxygenase-2 Function in Female Reproduction in Mice*

Endocrinology ◽  
2001 ◽  
Vol 142 (7) ◽  
pp. 3198-3206 ◽  
Author(s):  
Jeff Reese ◽  
Xuemei Zhao ◽  
Wen-Ge Ma ◽  
Naoko Brown ◽  
Timothy J. Maziasz ◽  
...  
Keyword(s):  
Early Pregnancy ◽  
Synergistic Effects ◽  
Female Reproduction ◽  
Cox Inhibitors ◽  
Cyclooxygenase 1 ◽  
Simultaneous Inhibition ◽  
Cox 2 ◽  
Alternative Sources ◽  
First Time ◽  
Cox 1

Abstract Cyclooxygenase (COX)-derived prostaglandins are critical in female reproduction. Gene targeting studies show that ovulation, fertilization, implantation, and decidualization are defective in COX-2 deficient mice. We used genetic and pharmacologic approaches to perturb COX function and examine the differential and synergistic effects of inhibition of COX-1, COX-2, or of both isoforms on reproductive outcomes during early pregnancy in mice. The results demonstrate that simultaneous inhibition of COX-1 and COX-2 produces more severe effects on early pregnancy events than inhibition of either isoform alone. The effects of pharmacological inhibition of COX-2 on female reproductive functions were less severe than the null mutation of the COX-2 gene. A combined approach showed that COX-2 inhibition in COX-1−/− mice induced complete reproductive failure, suggesting a lack of alternative sources of prostaglandin synthesis. This investigation raises caution regarding the indiscriminate use of COX inhibitors and shows for the first time the distinct and overlapping pathways of the cyclooxygenase systems in female reproduction.

Synthesis and evaluation of new benzimidazole-based COX inhibitors: a naproxen-like interaction detected by STD-NMR

RSC Advances ◽  
2015 ◽  
Vol 5 (61) ◽  
pp. 49098-49109 ◽  
Author(s):  
Luísa C. R. Carvalho ◽  
Daniela Ribeiro ◽  
Raquel S. G. R. Seixas ◽  
Artur M. S. Silva ◽  
Mariana Nave ◽  
...  
Keyword(s):  
Pharmacological Activity ◽  
Cox Inhibitors ◽  
Cyclooxygenase 1 ◽  
Inflammatory Drugs ◽  
Std Nmr ◽  
Cox 2 ◽  
Anti Inflammatory ◽  
Cox 1

Non-steroidal anti-inflammatory drugs exert their pharmacological activity through inhibition of cyclooxygenase 1 and 2 (COX-1 and COX-2).

Cyclooxygenase-2 inhibitors constrict the fetal lamb ductus arteriosus both in vitro and in vivo

2000 ◽  
Vol 278 (6) ◽  
pp. R1496-R1505 ◽  
Author(s):  
Yasushi Takahashi ◽  
Christine Roman ◽  
Sylvain Chemtob ◽  
Mary M. Tse ◽  
Emil Lin ◽  
...  
Keyword(s):  
Ductus Arteriosus ◽  
Plasma Concentrations ◽  
Additional Increase ◽  
Cox Inhibitors ◽  
Fetal Plasma ◽  
Cox 2 ◽  
Cox 2 Inhibitors ◽  
Cox 1

Nonselective cyclooxygenase (COX) inhibitors are potent tocolytic agents; however, they also have adverse fetal effects such as constriction of the fetal ductus arteriosus. Recently, selective COX-2 inhibitors have been used in the management of preterm labor in the hope of avoiding fetal complications. However, both COX-1 and -2 are expressed by cells of the ductus arteriosus. We used fetal lambs (0.88 gestation) to assess the ability of selective COX-2 inhibitors celecoxib and NS398 to affect the ductus arteriosus. Both selective COX-2 inhibitors decreased PGE2 and 6ketoPGF1α production in vitro; both inhibitors constricted the isolated ductus in vitro. The nonselective COX-1/COX-2 inhibitor indomethacin produced a further reduction in PG release and an additional increase in ductus tension in vitro. We used a prodrug of celecoxib to achieve 1.4 ± 0.6 μg/ml, mean ± standard deviation, of the active drug in vivo. This concentration of celecoxib produced both an increase in pressure gradient and resistance across the ductus; celecoxib also decreased fetal plasma concentrations of PGE2 and 6ketoPGF1α. Indomethacin (0.7 ± 0.2 μg/ml) produced a significantly greater fall in ductus blood flow than celecoxib and tended to have a greater effect on ductus resistence in vivo. We conclude that caution should be used when recommending COX-2 inhibitors for use in pregnant women, because COX-2 appears to play a significant role in maintaining patency of the fetal ductus arteriosus.

scholarly journals Synthesis and theoretical activity evaluation of a new steroid-oxazolone derivative against COX1-1 and COX-2

2019 ◽  
Vol 9 (4) ◽  
pp. 4107-4113
Keyword(s):  
Elemental Analysis ◽  
Cox Inhibitors ◽  
Activity Evaluation ◽  
Docking Model ◽  
Cox Inhibitor ◽  
Cox 2 ◽  
Cox 1

There are some reports for the preparation of several drugs as cyclooxygenase (COX) inhibitors; however, some reagents used in the preparation are expensive and difficult to handle. The aim of this study was to synthesize a steroid-oxazolone derivativeusing some reactions such as i) hydroxylation-amiination; ii) amidation; iii) alkynyl-addition; iv) aldolization and iv) imination. In addition, a theoretical ass was carried out to evaluate the interaction of both COX-1 and COX-2 with the steroid-oxazolone derivativeusing indomethacin and rofecoxib as controls in a docking model. The structure of the compounds obtained was confirmed through elemental analysis, spectroscopy and spectrometry data. The results showed that there are differences between the interaction of the steroidoxazolone derivativewith both COX 1 and COX 2 compared with the bound of indomethacin and rofecoxib with this type of enzymes. These data suggest that the steroid-oxazolone derivativecould be a good candidate as COX-inhibitor translated as a possible drug for treatment of pain.

Effects of cyclooxygenase inhibition on canine coronary artery blood flow and thrombosis

2008 ◽  
Vol 294 (1) ◽  
pp. H145-H155 ◽  
Author(s):  
Ting-Ting Hong ◽  
Jinbao Huang ◽  
Terrance D. Barrett ◽  
Benedict R. Lucchesi
Keyword(s):  
Coronary Artery ◽  
Vascular Reactivity ◽  
Thrombus Formation ◽  
Normal Coronary Artery ◽  
Cox Inhibitors ◽  
Inflammatory Conditions ◽  
Cox Inhibitor ◽  
Cox 2 ◽  
Cox 2 Inhibitors ◽  
Cox 1

This study was designed to determine the effect of inhibitors of cyclooxygenase (COX)-1, COX-2, and the nonselective COX inhibitor naproxen on coronary vasoactivity and thrombogenicity under baseline and lipopolysaccharide (LPS)-induced inflammatory conditions. We hypothesize that endothelial COX-1 is the primary COX isoform in the canine normal coronary artery, which mediates arachidonic acid (AA)-induced vasodilatation. However, COX-2 can be induced and overexpressed by inflammatory mediators and becomes the major local COX isoform responsible for the production of antithrombotic prostaglandins during systemic inflammation. The interventions included the selective COX-1 inhibitor SC-560 (0.3 mg/kg iv), the selective COX-2 inhibitor nimesulide (5 mg/kg iv), or the nonselective COX inhibitor naproxen (3 mg/kg iv). The selective prostacyclin (IP) receptor antagonist RO-3244794 (RO) was used as an investigational tool to delineate the role of prostacyclin (PGI2) in modulating vascular reactivity. AA-induced vasodilatation of the left circumflex coronary artery was suppressed to a similar extent by each of the COX inhibitors and RO. The data suggest that AA-induced vasodilatation in the normal coronary artery is mediated by a single COX isoform, the constitutive endothelial COX-1, which is reported to be susceptible to COX-2 inhibitors. The effect of the COX inhibitors on thrombus formation was evaluated in a model of carotid artery thrombosis secondary to electrolytic-induced vessel wall injury. Pretreatment with LPS (0.5 mg/kg iv) induced a systemic inflammatory response and prolonged the time-to-occlusive thrombus formation, which was reduced in the LPS-treated animals by the administration of nimesulide. In contrast, neither SC-560 nor naproxen influenced the time to thrombosis in the animals pretreated with LPS. The data are of significance in view of reported adverse cardiovascular events observed in clinical trials involving the use of selective COX-2 inhibitors, thereby suggesting that the endothelial constitutive COX-1 and the inducible vascular COX-2 serve important functions in maintaining vascular homeostasis.

scholarly journals DESIGN, SYNTHESIS AND BIOLOGICAL SCREENING OF AMINOACETYLENIC TETRAHYDROPHTHALIMIDE ANALOGUES AS NOVEL CYCLOOXYGENASE (COX) INHIBITORS

2017 ◽  
Vol 9 (2) ◽  
pp. 160
Author(s):  
Ahmed Basim ◽  
Zuhair A. Muhi Eldeen ◽  
Elham N. Al-kaissi ◽  
Ghadeer Suaifan ◽  
Mohammad A. Ghattas ◽  
...  
Keyword(s):  
Elemental Analysis ◽  
Inhibitory Activity ◽  
Aryl Group ◽  
Design Synthesis ◽  
Cox Inhibitors ◽  
H Nmr ◽  
Phthalimide Derivative ◽  
Cox 2 ◽  
Cox 1 ◽  
C Nmr

<p><strong>Objective: </strong>To design and synthesise a new amino acetylenic tetrahydro phthalimide derivative and investigate their selective inhibitory activity to COXs.</p><p><strong>Methods: </strong>Aminoacetylenic tetrahydro phthalimide derivatives were synthesised by alkylation of tetrahydro phthalimide with propargyl bromide afforded 2-(prop-2-yn-1-yl)-2,3,3a,4,7,7a-hexahydro-1H-isoindole-1,3-dione. The alkylated tetrahydro phthalimide was subjected to Mannich reaction afforded the desired amino acetylenic tetra phthalimide derivatives (AZ 1-6). The elemental analysis was indicated by the EuroEA elemental analyzer and biological characterization was via IR, <sup>1</sup>H-NMR, [13]C-NMR, DSC was determined with the aid of Bruker FT-IR and Varian 300 MHz spectrometer and DMSO-d<sub>6</sub> as a solvent, molecular docking was done using the Autodock Tool software (version 4.2). ChemBioDraw was used in the drawing of our schemes.</p><p><strong>Results</strong>:<strong> </strong>The IR, <sup>1</sup>H-NMR, <sup>13</sup>C-NMR, DSC and elemental analysis were consistent with the assigned structures. The designers of the compounds as COXs inhibitor activity were based on the nationalisation of the important criteria that provide effective inhibitory binding with COXs–receptor. The results indicated that the synthesised compounds (AZ1-6) showed a close similarity in the binding affinity to both COXs and may be more specific to COX-1. AZ-5 showed the highest % of inhibition for COX-1 even better than aspirin. Which may suggest that the aryl group is required for COX-2 inhibition.</p><p><strong>Conclusion: </strong>For the first time, we indicate the requirement of aromaticity in COX-2 structural inhibitory activity. </p>

scholarly journals Melatonin Modulation of Radiation and Chemotherapeutics-induced Changes on Differentiation of Breast Fibroblasts

2019 ◽  
Vol 20 (16) ◽  
pp. 3935 ◽  
Author(s):  
Alicia González-González ◽  
Enrique García Nieto ◽  
Alicia González ◽  
Cristina Sánchez-Fernández ◽  
Carolina Alonso-González ◽  
...  
Keyword(s):  
Inhibitory Effect ◽  
Aromatase Activity ◽  
Proliferation And Differentiation ◽  
Cox 2 ◽  
Regulatory Effects ◽  
Factor Α ◽  
Induced Changes ◽  
Pparγ Expression ◽  
Cox 1 ◽  
Breast Fibroblasts

Melatonin exerts oncostatic actions and sensitizes tumor cells to chemotherapeutics or radiation. In our study, we investigated the effects of docetaxel, vinorelbine, and radiation on human breast fibroblasts and its modulation by melatonin. Docetaxel or vinorelbine inhibits proliferation and stimulates the differentiation of breast preadipocytes, by increasing C/EBPα and PPARγ expression and by downregulating tumor necrosis factor α (TNFα), interleukin 6 (IL-6), and IL-11 expression. Radiation inhibits both proliferation and differentiation through the downregulation of C/EBPα and PPARγ and by stimulating TNFα expression. In addition, docetaxel and radiation decrease aromatase activity and expression by decreasing aromatase promoter II and cyclooxygenases 1 and 2 (COX-1 and COX-2) expression. Melatonin potentiates the stimulatory effect of docetaxel and vinorelbine on differentiation and their inhibitory effects on aromatase activity and expression, by increasing the stimulatory effect on C/EBPα and PPARγ expression and the downregulation of antiadipogenic cytokines and COX expression. Melatonin also counteracts the inhibitory effect of radiation on differentiation of preadipocytes, by increasing C/EBPα and PPARγ expression and by decreasing TNFα expression. Melatonin also potentiates the inhibitory effect exerted by radiation on aromatase activity and expression by increasing the downregulation of promoter II, and COX-1 and COX-2 expression. Our findings suggest that melatonin modulates regulatory effects induced by chemotherapeutic drugs or radiation on preadipocytes, which makes it a promising adjuvant for chemotherapy and radiotherapy sensibilization.

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